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  1. Energy Transition Initiative, Island Energy Snapshot - Grenada (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2015-03-01

    This profile provides a snapshot of the energy landscape of Grenada - a small island nation consisting of the island of Grenada and six smaller islands in the southeastern Caribbean Sea - three of which are inhabited: Grenada, Carriacou, and Petite Martinique.

  2. Grenada-Caribbean Community (CARICOM) Sustainable Energy Roadmap...

    Open Energy Info (EERE)

    Grenada-Caribbean Community (CARICOM) Sustainable Energy Roadmap and Strategy Jump to: navigation, search Name Grenada-Caribbean Community (CARICOM) Sustainable Energy Roadmap and...

  3. Grenada: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Country Profile Name Grenada Population 109,590 GDP 790,000,000 Energy Consumption 0.00 Quadrillion Btu 2-letter ISO code GD 3-letter ISO code GRD Numeric ISO...

  4. Guadeloupe: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Country Profile Name Guadeloupe Population Unavailable GDP Unavailable Energy Consumption 0.03 Quadrillion Btu 2-letter ISO code GP 3-letter ISO code GLP Numeric ISO...

  5. Grenada-Pilot Program for Climate Resilience (PPCR) | Open Energy...

    Open Energy Info (EERE)

    Pilot Program for Climate Resilience (PPCR) Jump to: navigation, search Name Grenada-Pilot Program for Climate Resilience (PPCR) AgencyCompany Organization World Bank Sector...

  6. Caribbean-NREL Cooperation | Open Energy Information

    Open Energy Info (EERE)

    internatio Country Anguilla, Antigua and Barbuda, Aruba, Bahamas, Barbados, Cuba, Dominica, Dominican Republic, Grenada, Guadeloupe, Haiti, Jamaica, Martinique, Saint...

  7. Caribbean-GTZ Renewable Energy Program | Open Energy Information

    Open Energy Info (EERE)

    enpraxis95 Country Antigua & Barbuda, Aruba, Bahamas, Barbados, Cayman Islands, Cuba, Dominica, Dominican Republic, Grenada, Guadeloupe, Haiti, Jamaica, Martinique, Puerto...

  8. Energy Transition Initiative: Island Energy Snapshot - Guadeloupe; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    2015-05-27

    This profile provides a snapshot of the energy landscape of Guadeloupe, an overseas region of France located in the eastern Caribbean Sea. Guadeloupe’s utility rates are approximately $0.18 U.S. dollars (USD) per kilowatt-hour (kWh), below the Caribbean regional average of $0.33 USD/kWh.

  9. Complex systems influence melting of Greenland ice sheet

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    melting of Greenland ice sheet Complex systems influence melting of Greenland ice sheet International research team's field work shows that, well, things are more complicated...

  10. Greenland Ice Sheet Modeling Update (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Greenland Ice Sheet Modeling Update Citation Details In-Document Search Title: Greenland Ice Sheet Modeling Update You are accessing a document from the Department of Energy's...

  11. Greenland: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Country Profile Name Greenland Population 56,968 GDP Unavailable Energy Consumption 0.01 Quadrillion Btu 2-letter ISO code GL 3-letter ISO code GRL Numeric ISO...

  12. Hainan Greenland Microalgae Biotechnology Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Microalgae Biotechnology Co Ltd Jump to: navigation, search Name: Hainan Greenland Microalgae Biotechnology Co Ltd Place: Hainan Province, China Product: Chinese biotechnology firm...

  13. Team advances understanding of the Greenland Ice Sheet's meltwater...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    drainage system are lacking and its evolution over the melt season is poorly understood. "Everyone wants to know what's happening under Greenland as it experiences more and...

  14. Greenland, New Hampshire: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Greenland, New Hampshire: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 43.0361995, -70.8328322 Show Map Loading map... "minzoom":false,"mapp...

  15. ARM - Field Campaign - Lidar support for ICECAPS at Summit, Greenland

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govCampaignsLidar support for ICECAPS at Summit, Greenland Campaign Links ICECAPS Campaign Summary (PDF) Summit Station Research Highlight New Data from Greenland for Arctic Climate Research Cloud Cocktail Melts Greenland Ice Sheet Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Lidar support for ICECAPS at Summit, Greenland 2010.04.15 - 2018.08.31 Lead Scientist : David Turner Abstract Beginning in May 2010, the Integrated

  16. Greenland in RASM (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Greenland in RASM Authors: Lipscomb, William Henry 1 + Show Author Affiliations Los Alamos National Laboratory Publication Date: ...

  17. Sandia's ice sheet modeling of Greenland, Antarctica helps predict

    National Nuclear Security Administration (NNSA)

    sea-level rise | National Nuclear Security Administration | (NNSA) Sandia's ice sheet modeling of Greenland, Antarctica helps predict sea-level rise Wednesday, March 2, 2016 - 12:00am Sandia California researchers Irina Tezaur and Ray Tuminaro analyze a model of Antarctica. They are part of a Sandia team working to improve the reliability and efficiency of computational models that describe ice sheet behavior and dynamics. The Greenland and Antarctic ice sheets will make a dominant

  18. Complex systems influence melting of Greenland ice sheet

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Complex systems influence melting of Greenland ice sheet Complex systems influence melting of Greenland ice sheet International research team's field work shows that, well, things are more complicated than we thought December 22, 2014 The newly discovered rolling movement shown in (A) three-dimensional cryo-electron microscopy image of ribosome, and (B) computer-generated atomic-resolution model of the human ribosome consistent with microscopy. An international team of researchers deployed to

  19. New climate model predicts likelihood of Greenland ice melt, sea level rise

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and dangerous temperatures New climate model predicts likelihood of Greenland ice melt New climate model predicts likelihood of Greenland ice melt, sea level rise and dangerous temperatures A new computer model of accumulated carbon emissions predicts the likelihood of crossing several dangerous climate change thresholds. November 20, 2015 Greenland ice loss. Greenland ice loss. Contact Kevin Roark Communications Office (505) 665-9202 Email "The model is based on idealized

  20. Update on Greenland Ice Sheet Simulations In CISM and CESM (Conference...

    Office of Scientific and Technical Information (OSTI)

    Title: Update on Greenland Ice Sheet Simulations In CISM and CESM Authors: Lipscomb, William Henry 1 + Show Author Affiliations Los Alamos National Laboratory Publication Date: ...

  1. Runoff simulations from the Greenland ice sheet at Kangerlussuaq from 2006-2007 to 2007/08. West Greenland

    SciTech Connect (OSTI)

    Mernild, Sebastian Haugard [Los Alamos National Laboratory; Hasholt, Bent [UNIV OF COPENHAGEN; Van Den Broeke, Michiel [UTRECHT UNIV; Liston, Glen [COLORADO STATE UNIV

    2009-01-01

    This study focuses on runoff from a large sector of the Greenland Ice Sheet (GrIS) - the Kangerlussuaq drainage area, West Greenland - for the runoff observation period 2006/07 to 2007/08. SnowModel, a state-of-the-art snow-evolution modeling system, was used to simulate winter accumulation and summer ablation processes, including runoff. Independent in situ end-of-winter snow depth and high-resolution runoff observations were used for validation of simulated accumulation and ablation processes. Runoff was modeled on both daily and hourly time steps, filling a data gap of runoff exiting part of the GrIS. Using hourly meteorological driving data instead of smoothed daily-averaged data produced more realistic meteorological conditions in relation to snow and melt threshold surface processes, and produced 6-17% higher annual cumulative runoff. The simulated runoff series yielded useful insights into the present conditions of inter-seasonal and inter-annual variability of Kangerlussuaq runoff, and provided an acceptable degree of agreement between simulated and observed runoff. The simulated spatial runoff distributions, in some areas of the GrIS terminus, were as high as 2,750 mm w.eq. of runoff for 2006/07, while only 900 mm w.eq was simulated for 2007/08. The simulated total runoff from Kangerlussuaq was 1.9 km{sup 3} for 2006/07 and 1.2 km{sup 3} for 2007/08, indicating a reduction of 35-40% caused by the climate conditions and changes in the GrIS freshwater storage. The reduction in runoff from 2006/07 to 2007/08 occurred simultaneously with the reduction in the overall pattern of satellite-derived GrIS surface melt from 2007 to 2008.

  2. Meltwater effects on flow of Greenland's ice sheet less severe for sea

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    level rise than earlier feared, scientists say Side effects of increasing meltwater less severe than feared Meltwater effects on flow of Greenland's ice sheet less severe for sea level rise than earlier feared, scientists say The team found that accelerating ice sheet movement from increasing meltwater lubrication is likely to have only a minor role in future sea-level rise. August 19, 2013 A stream of meltwater on the surface of the Greenland Ice Sheet enters a moulin connecting to the

  3. Meltwater effects on flow of Greenland's ice sheet less severe for sea

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    level rise than earlier feared, scientists say Stories » Side effects of increasing meltwater less severe than feared Meltwater effects on flow of Greenland's ice sheet less severe for sea level rise than earlier feared, scientists say The team found that accelerating ice sheet movement from increasing meltwater lubrication is likely to have only a minor role in future sea-level rise. August 19, 2013 A stream of meltwater on the surface of the Greenland Ice Sheet enters a moulin connecting

  4. Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    de la Peña, S.; Howat, I. M.; Nienow, P. W.; van den Broeke, M. R.; Mosley-Thompson, E.; Price, S. F.; Mair, D.; Noël, B.; Sole, A. J.

    2015-06-11

    Atmospheric warming over the Greenland Ice Sheet during the last 2 decades has increased the amount of surface meltwater production, resulting in the migration of melt and percolation regimes to higher altitudes and an increase in the amount of ice content from refrozen meltwater found in the firn above the superimposed ice zone. Here we present field and airborne radar observations of buried ice layers within the near-surface (0–20 m) firn in western Greenland, obtained from campaigns between 1998 and 2014. We find a sharp increase in firn-ice content in the form of thick widespread layers in the percolation zone,more » which decreases the capacity of the firn to store meltwater. The estimated total annual ice content retained in the near-surface firn in areas with positive surface mass balance west of the ice divide in Greenland reached a maximum of 74 ± 25 Gt in 2012, compared to the 1958–1999 average of 13 ± 2 Gt, while the percolation zone area more than doubled between 2003 and 2012. Increased melt and column densification resulted in surface lowering averaging –0.80 ± 0.39 m yr⁻¹ between 1800 and 2800 m in the accumulation zone of western Greenland. Since 2007, modeled annual melt and refreezing rates in the percolation zone at elevations below 2100 m surpass the annual snowfall from the previous year, implying that mass gain in the region is retained after melt in the form of refrozen meltwater. If current melt trends over high elevation regions continue, subsequent changes in firn structure will have implications for the hydrology of the ice sheet and related abrupt seasonal densification could become increasingly significant for altimetry-derived ice sheet mass balance estimates.« less

  5. History of ancient copper smelting pollution during Roman and Medieval times recorded in Greenland ice

    SciTech Connect (OSTI)

    Hong, Sungmin; Candelone, J.P.; Patterson, C.C.; Boultron, C.F.

    1996-04-12

    Determination of copper concentrations in Greenland ice dated from seven millennia ago to the present showed values exceeding natural levels, beginning about 2500 years ago. This early large-scale pollution of the atmosphere of the Northern Hemisphere is attributed to emissions from the crude, highly polluting smelting technologies used for copper production during Roman and medieval times, especially in Europe and China. This study opens the way to a quantitative assessment of the history of early metal production, which was instrumental in the development of human cultures during ancient eras. 27 refs., 1 fig., 2 tabs.

  6. Grenada-Caribbean Solar Finance Program | Open Energy Information

    Open Energy Info (EERE)

    through: (1) a training program for lending officers, (2) a consumer awareness campaign, and (3) a pilot lending operation." References "OAS Project Database" Retrieved...

  7. Heat sources within the Greenland Ice Sheet: dissipation, temperate paleo-firn and cryo-hydrologic warming

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lüthi, M. P.; Ryser, C.; Andrews, L. C.; Catania, G. A.; Funk, M.; Hawley, R. L.; Hoffman, M. J.; Neumann, T. A.

    2015-01-01

    Ice temperature profiles from the Greenland Ice Sheet contain information on the deformation history, past climates and recent warming. We present full-depth temperature profiles from two drill sites on a flow line passing through Swiss Camp, West Greenland. Numerical modeling reveals that ice temperatures are considerably higher than would be expected from heat diffusion and dissipation alone. The possible causes for this extra heat are evaluated using a Lagrangian heat flow model. The model results reveal that the observations can be explained with a combination of different processes: enhanced dissipation (strain heating) in ice-age ice, temperate paleo-firn, and cryo-hydrologic warmingmore » in deep crevasses.« less

  8. Heat sources within the Greenland Ice Sheet: dissipation, temperate paleo-firn and cryo-hydrologic warming

    SciTech Connect (OSTI)

    Lthi, M. P.; Ryser, C.; Andrews, L. C.; Catania, G. A.; Funk, M.; Hawley, R. L.; Hoffman, M. J.; Neumann, T. A.

    2015-01-01

    Ice temperature profiles from the Greenland Ice Sheet contain information on the deformation history, past climates and recent warming. We present full-depth temperature profiles from two drill sites on a flow line passing through Swiss Camp, West Greenland. Numerical modeling reveals that ice temperatures are considerably higher than would be expected from heat diffusion and dissipation alone. The possible causes for this extra heat are evaluated using a Lagrangian heat flow model. The model results reveal that the observations can be explained with a combination of different processes: enhanced dissipation (strain heating) in ice-age ice, temperate paleo-firn, and cryo-hydrologic warming in deep crevasses.

  9. Meltwater flux and runoff modeling in the abalation area of jakobshavn Isbrae, West Greenland

    SciTech Connect (OSTI)

    Mernild, Sebastian Haugard [Los Alamos National Laboratory; Chylek, Petr [Los Alamos National Laboratory; Liston, Glen [COLORADO STATE UNIV.; Steffen, Konrad [UNIV OF COLORADO

    2009-01-01

    The temporal variability in surface snow and glacier melt flux and runoff were investigated for the ablation area of lakobshavn Isbrae, West Greenland. High-resolution meteorological observations both on and outside the Greenland Ice Sheet (GrIS) were used as model input. Realistic descriptions of snow accumulation, snow and glacier-ice melt, and runoff are essential to understand trends in ice sheet surface properties and processes. SnowModel, a physically based, spatially distributed meteorological and snow-evolution modeling system was used to simulate the temporal variability of lakobshavn Isbrre accumulation and ablation processes for 2000/01-2006/07. Winter snow-depth observations and MODIS satellite-derived summer melt observations were used for model validation of accumulation and ablation. Simulations agreed well with observed values. Simulated annual surface melt varied from as low as 3.83 x 10{sup 9} m{sup 3} (2001/02) to as high as 8.64 x 10{sup 9} m{sup 3} (2004/05). Modeled surface melt occurred at elevations reaching 1,870 m a.s.l. for 2004/05, while the equilibrium line altitude (ELA) fluctuated from 990 to 1,210 m a.s.l. during the simulation period. The SnowModel meltwater retention and refreezing routines considerably reduce the amount of meltwater available as ice sheet runoff; without these routines the lakobshavn surface runoff would be overestimated by an average of 80%. From September/October through May/June no runoff events were simulated. The modeled interannual runoff variability varied from 1.81 x 10{sup 9} m{sup 3} (2001/02) to 5.21 x 10{sup 9} m{sup 3} (2004/05), yielding a cumulative runoff at the Jakobshavn glacier terminus of {approx}2.25 m w.eq. to {approx}4.5 m w.eq., respectively. The average modeled lakobshavn runoff of {approx}3.4 km{sup 3} y{sup -1} was merged with previous estimates of Jakobshavn ice discharge to quantify the freshwater flux to Illulissat Icefiord. For both runoff and ice discharge the average trends are

  10. Seismicity on the western Greenland Ice Sheet: Surface fracture in the vicinity of active moulins

    SciTech Connect (OSTI)

    Carmichael, Joshua D.; Joughin, Ian; Behn, Mark D.; Das, Sarah; King, Matt A.; Stevens, Laura; Lizarralde, Dan

    2015-06-25

    We analyzed geophone and GPS measurements collected within the ablation zone of the western Greenland Ice Sheet during a ~35 day period of the 2011 melt season to study changes in ice deformation before, during, and after a supraglacial lake drainage event. During rapid lake drainage, ice flow speeds increased to ~400% of winter values, and icequake activity peaked. At times >7 days after drainage, this seismicity developed variability over both diurnal and longer periods (~10 days), while coincident ice speeds fell to ~150% of winter values and showed nightly peaks in spatial variability. Approximately 95% of all detected seismicity in the lake basin and its immediate vicinity was triggered by fracture propagation within near-surface ice (<330 m deep) that generated Rayleigh waves. Icequakes occurring before and during drainage frequently were collocated with the down flow (west) end of the primary hydrofracture through which the lake drained but shifted farther west and outside the lake basin after the drainage. We interpret these results to reveal vertical hydrofracture opening and local uplift during the drainage, followed by enhanced seismicity and ice flow on the downstream side of the lake basin. This region collocates with interferometric synthetic aperture radar-measured speedup in previous years and could reflect the migration path of the meltwater supplied to the bed by the lake. The diurnal seismic signal can be associated with nightly reductions in surface melt input that increase effective basal pressure and traction, thereby promoting elevated strain in the surficial ice.

  11. Microwave signatures of ice hydrometeors from ground-based observations above Summit, Greenland

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pettersen, Claire; Bennartz, Ralf; Kulie, Mark S.; Merrelli, Aronne J.; Shupe, Matthew D.; Turner, David D.

    2016-04-15

    Multi-instrument, ground-based measurements provide unique and comprehensive data sets of the atmosphere for a specific location over long periods of time and resulting data compliment past and existing global satellite observations. This paper explores the effect of ice hydrometeors on ground-based, high-frequency passive microwave measurements and attempts to isolate an ice signature for summer seasons at Summit, Greenland, from 2010 to 2013. Data from a combination of passive microwave, cloud radar, radiosonde, and ceilometer were examined to isolate the ice signature at microwave wavelengths. By limiting the study to a cloud liquid water path of 40 gm–2 or less, themore » cloud radar can identify cases where the precipitation was dominated by ice. These cases were examined using liquid water and gas microwave absorption models, and brightness temperatures were calculated for the high-frequency microwave channels: 90, 150, and 225 GHz. By comparing the measured brightness temperatures from the microwave radiometers and the calculated brightness temperature using only gas and liquid contributions, any residual brightness temperature difference is due to emission and scattering of microwave radiation from the ice hydrometeors in the column. The ice signature in the 90, 150, and 225 GHz channels for the Summit Station summer months was isolated. As a result, this measured ice signature was then compared to an equivalent brightness temperature difference calculated with a radiative transfer model including microwave single-scattering properties for several ice habits. Initial model results compare well against the 4 years of summer season isolated ice signature in the high-frequency microwave channels.« less

  12. Seismicity on the western Greenland Ice Sheet: Surface fracture in the vicinity of active moulins

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Carmichael, Joshua D.; Joughin, Ian; Behn, Mark D.; Das, Sarah; King, Matt A.; Stevens, Laura; Lizarralde, Dan

    2015-06-25

    We analyzed geophone and GPS measurements collected within the ablation zone of the western Greenland Ice Sheet during a ~35 day period of the 2011 melt season to study changes in ice deformation before, during, and after a supraglacial lake drainage event. During rapid lake drainage, ice flow speeds increased to ~400% of winter values, and icequake activity peaked. At times >7 days after drainage, this seismicity developed variability over both diurnal and longer periods (~10 days), while coincident ice speeds fell to ~150% of winter values and showed nightly peaks in spatial variability. Approximately 95% of all detected seismicitymore » in the lake basin and its immediate vicinity was triggered by fracture propagation within near-surface ice (<330 m deep) that generated Rayleigh waves. Icequakes occurring before and during drainage frequently were collocated with the down flow (west) end of the primary hydrofracture through which the lake drained but shifted farther west and outside the lake basin after the drainage. We interpret these results to reveal vertical hydrofracture opening and local uplift during the drainage, followed by enhanced seismicity and ice flow on the downstream side of the lake basin. This region collocates with interferometric synthetic aperture radar-measured speedup in previous years and could reflect the migration path of the meltwater supplied to the bed by the lake. The diurnal seismic signal can be associated with nightly reductions in surface melt input that increase effective basal pressure and traction, thereby promoting elevated strain in the surficial ice.« less

  13. Diagenesis and porosity development associated with major sea level fluctuations, Upper Permian, Jameson land, east Greenland

    SciTech Connect (OSTI)

    Scholle, P.A.; Ulmer, D.S. ); Stemmerik, L. )

    1990-05-01

    The Upper Permian of Jameson Land includes two major carbonate sequences, represented by the Karstryggen and Wegener Halvoe formations. The initial Karstryggen transgression led to the development of a shallow marine platform with structurally controlled evaporite basins (salinas) separated by stromatolitic, peloidal, or micritic carbonate depositional areas. The Wegener Havloe sequence reflects more rapid and extensive transgression with the deposition of three subcycles of fully marine, platform, or biohermal carbonates containing minor evaporites near the basin margins. Bioherms (bryozoan-brachiopod-marine cement mounds) show > 100 m of relief, indicating that large relative sea level changes were involved. Both the Karstryggen and Wgener Havloe cycles were terminated by major regressions, which led to karstic and/or fluvial incision of the underlying sequences. Not surprisingly, carbonate and evaporite diagenesis was greatly affected by these regional or eustatic sea level fluctuations. Evaporites dissolved or were replaced by calcite and celestite under the influence of meteoric waters. Limestones show collapse brecciation, grain leaching, soil development, and characteristic vadose and phreatic cements. Most significantly meteoric flushing led to massive dissolution of botryoidal marine cements (aragonite and probable high-Mg calcite) within biohermal facies on the Wegener Peninsula. This early porosity resurrection led to the preservation of porous bioherm core zones until hydrocarbon migration. Only late (posthydrocarbon), probably hydrothermal fluid flow led to cementation of the bioherm cores while expelling most of the reservoired hydrocarbons. If the sea level changes affecting the Greenlandic Permian are eustatic, then this study may provide significant clues to porosity development throughout the largely unexplored northern Zechstein basin.

  14. Depositional environment and organic geochemistry of the Upper Permian Ravenfjeld Formation source rock in East Greenland

    SciTech Connect (OSTI)

    Christiansen, F.G.; Piasecki, S.; Stemmerik, L. ); Telnaes, N. )

    1993-09-01

    The Upper Permian Ravnefjeld Formation in East Greenland is composed of shales that laterally pass into carbonate buildups and platforms of the Wegener Halvo Formation. The Ravnefjeld Formation is subdivided into five units that can be traced throughout the Upper Permian depositional basin. Two of the units are laminated and organic rich and were deposited under anoxic conditions. They are considered good to excellent source rocks for liquid hydrocarbons with initial average TOC (total organic carbon) values between 4 and 5% and HI (hydrogen index) between 300 and 400. The cumulative source rocks are separated and enclosed by three units of bioturbated siltstone with a TOC of less than 0.5% and an HI of less than 100. These siltstones were deposited under relatively oxic conditions. The organic geochemistry of the source rocks is typical for marine source rocks with some features normally associated with carbonate/evaporite environments [low Pr/Ph (pristane/phytane), low CPI (carbon preference index), distribution of tricyclic and pentacyclic terpanes]. The establishment of anoxic conditions and subsequent source rock deposition was controlled by eustatic sea level changes. The subenvironment (paleogeographic setting, influx of carbonate material, water depth, salinity) has some influence on a number of bulk parameters [TOC-HI relations, TOC-TS (total sulfur) relations] and, in particular, biomarker parameters such as Pr/Ph and terpane ratios. All the basal shales or shales in the vicinity of carbonate buildups of platforms are characterized by low Pr/Ph, high C[sub 23] tricyclic terpanes, and high C[sub 35] and C[sub 33] hopanes. 52 refs., 20 figs., 3 tabs.

  15. Greenland ice sheet surface mass-balance modeling in a 131-year perspective, 1950-2080

    SciTech Connect (OSTI)

    Mernild, Sebastian Haugard; Liston, Glen; Hiemstra, Christopher; Christensen, Jens

    2009-01-01

    Fluctuations in the Greenland Ice Sheet (GrIS) surface mass-balance (SMB) and freshwater influx to the surrounding oceans closely follow climate fluctuations and are of considerable importance to the global eustatic sea level rise. SnowModel, a state-of-the-art snow-evolution modeling system, was used to simulate variations in the GrIS melt extent, surface water balance components, changes in SMB, and freshwater influx to the ocean. The simulations are based on the IPCC scenario AlB modeled by the HIRHAM4 RCM (using boundary conditions from ECHAM5 AOGCM) from 1950 through 2080. In-situ meteorological station (GC-Net and WMO DMI) observations from inside and outside the GrIS were used to validate and correct RCM output data before it was used as input for SnowModel. Satellite observations and independent SMB studies were used to validate the SnowModel output and confirm the model's robustness. We simulated a {approx}90% increase in end-of-summer surface melt extent (0.483 x 10{sup 6} km{sup 2}) from 1950 to 2080, and a melt index (above 2,000-m elevation) increase of 138% (1.96 x 10{sup 6} km{sup 2} x days). The greatest difference in melt extent occured in the southern part of the GrIS, and the greatest changes in the number of melt days was seen in the eastern part of the GrIS ({approx}50-70%) and was lowest in the west ({approx}20-30%). The rate of SMB loss, largely tied to changes in ablation processes, lead to an enhanced average loss of 331 km{sup 3} from 1950 to 2080, an average 5MB level of -99 km{sup 3} for the period 2070-2080. GrIS surface freshwater runoff yielded an eustatic rise in sea level from 0.8 {+-} 0.1 (1950-1959) to 1.9 {+-} 0.1 mm (2070-2080) sea level equivalent (SLE) y{sup -1}. The accumulated GrIS freshwater runoff contribution from surface melting equaled 160 mm SLE from 1950 through 2080.

  16. Greenland and Antarctic mass balances for present and doubled atmospheric CO{sub 2} from the GENESIS version-2 global climate model

    SciTech Connect (OSTI)

    Thompson, S.L.; Pollard, D.

    1997-05-01

    As anthropogenic greenhouse warming occurs in the next century, changes in the mass balances of Greenland and Antarctica will probably accelerate and may have significant effects on global sea level. Recent trends and possible future changes in these mass balances have received considerable attention in the glaciological literature, but until recently relatively few general circulation modeling (GCM) studies have focused on the problem. However, there are two significant problems in using GCMs to predict mass balance distributions on ice sheets: (i) the relatively coarse GCM horizontal resolution truncates the topography of the ice-sheet flanks and smaller ice sheets such as Greenland, and (ii) the snow and ice physics in most GCMs does not include ice-sheet-specific processes such as the refreezing of meltwater. Two techniques are described that attack these problems, involving (i) an elevation-based correction to the surface meteorology and (ii) a simple a posteriori correction for the refreezing of meltwater following Pfeiffer et al. Using these techniques in a new version 2 of the Global Environmental and Ecological Simulation of Interactive Systems global climate model, the authors present global climate and ice-sheet mass-balance results from two equilibrated runs for present and doubled atmospheric CO{sub 2}. This GCM is well suited for ice-sheet mass-balance studies because (a) the surface can be represented at a finer resolution (2{degrees} lat x 2{degrees} long) than the atmospheric GCM, (b) the two correction techniques are included as part of the model, and the model`s mass balances for present-day Greenland and Antarctica are realistic. 131 refs., 23 figs., 2 tabs.

  17. Diagenetic history and hydrocarbon potential of Upper Permian carbonate buildups, Wegener Halvoe area, Jameson Land basin, east Greenland

    SciTech Connect (OSTI)

    Scholle, P.A.; Ulmer, D.S. ); Stemmerik, L. )

    1991-04-01

    The Upper Permian of Jameson Land includes two carbonate sequences, the Karstryggen and Wegener Halvoe formations. The Karstryggen Formation contains hypersaline carbonates and localized evaporites that were heavily weathered and dissected prior to deposition of the overlying strata. The overlying Wegener Halvoe Formation represents an abrupt and extensive marine inundation over the underlying karstified Karstryggen surface. Bryozoan-brachiopod-algal-cement buildups of the Wegener Halvoe Formation are localized on karstic highs, and show up to 150 m of depositional relief. The diagenetic histories of the core and flank facies are very different. Core facies porosity was initially obliterated by marine cements, but repeated meteoric exposure altered unstable core facies constituents. This alteration produced extensive secondary porosity through grain and cement leaching with local collapse brecciation. Flank strata, however, underwent little sea-floor diagenesis, and low permeability and mineralogically stable grain composition protected these strata from meteoric alteration. Subsequent fracturing and hydrothermal fluid flow, however, flushed hydrocarbons and filled pores with ferroan calcite, barite, fluorite, galena, and baroque dolomite. This heating and flushing is thought to have been especially intense in the Wegener Halvoe region; thus, more basinal areas may still have reservoirs containing significant oil in equivalent Upper Permian limestones. If, as is likely, the sea level changes affecting the Greenland Permian were eustatic, then this study may provide significant clues to porosity development throughout the largely unexplored northern Zechstein basin and the Arctic basin of the Barent Sea. This study also provides some important connections to the probably time-equivalent Guadalupian carbonate reservoir rocks of west Texas-New Mexico and Wyoming.

  18. On the scalability of the Albany/FELIX first-order Stokes approximation ice sheet solver for large-scale simulations of the Greenland and Antarctic ice sheets

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tezaur, Irina K.; Tuminaro, Raymond S.; Perego, Mauro; Salinger, Andrew G.; Price, Stephen F.

    2015-01-01

    We examine the scalability of the recently developed Albany/FELIX finite-element based code for the first-order Stokes momentum balance equations for ice flow. We focus our analysis on the performance of two possible preconditioners for the iterative solution of the sparse linear systems that arise from the discretization of the governing equations: (1) a preconditioner based on the incomplete LU (ILU) factorization, and (2) a recently-developed algebraic multigrid (AMG) preconditioner, constructed using the idea of semi-coarsening. A strong scalability study on a realistic, high resolution Greenland ice sheet problem reveals that, for a given number of processor cores, the AMG preconditionermore » results in faster linear solve times but the ILU preconditioner exhibits better scalability. A weak scalability study is performed on a realistic, moderate resolution Antarctic ice sheet problem, a substantial fraction of which contains floating ice shelves, making it fundamentally different from the Greenland ice sheet problem. Here, we show that as the problem size increases, the performance of the ILU preconditioner deteriorates whereas the AMG preconditioner maintains scalability. This is because the linear systems are extremely ill-conditioned in the presence of floating ice shelves, and the ill-conditioning has a greater negative effect on the ILU preconditioner than on the AMG preconditioner.« less

  19. The influence of air temperature inversions on snowmelt and glacier mass-balance simulations, Ammassalik island, SE Greenland

    SciTech Connect (OSTI)

    Mernild, Sebastian Haugard [Los Alamos National Laboratory; Liston, Glen [COLORADO STATE UNIV.

    2009-01-01

    In many applications, a realistic description of air temperature inversions is essential for accurate snow and glacier ice melt, and glacier mass-balance simulations. A physically based snow-evolution modeling system (SnowModel) was used to simulate eight years (1998/99 to 2005/06) of snow accumulation and snow and glacier ice ablation from numerous small coastal marginal glaciers on the SW-part of Ammassalik Island in SE Greenland. These glaciers are regularly influenced by inversions and sea breezes associated with the adjacent relatively low temperature and frequently ice-choked fjords and ocean. To account for the influence of these inversions on the spatiotemporal variation of air temperature and snow and glacier melt rates, temperature inversion routines were added to MircoMet, the meteorological distribution sub-model used in SnowModel. The inversions were observed and modeled to occur during 84% of the simulation period. Modeled inversions were defined not to occur during days with strong winds and high precipitation rates due to the potential of inversion break-up. Field observations showed inversions to extend from sea level to approximately 300 m a.s.l., and this inversion level was prescribed in the model simulations. Simulations with and without the inversion routines were compared. The inversion model produced air temperature distributions with warmer lower elevation areas and cooler higher elevation areas than without inversion routines due to the use of cold sea-breeze base temperature data from underneath the inversion. This yielded an up to 2 weeks earlier snowmelt in the lower areas and up to 1 to 3 weeks later snowmelt in the higher elevation areas of the simulation domain. Averaged mean annual modeled surface mass-balance for all glaciers (mainly located above the inversion layer) was -720 {+-} 620 mm w.eq. y{sup -1} for inversion simulations, and -880 {+-} 620 mm w.eq. y{sup -1} without the inversion routines, a difference of 160 mm w.eq. y

  20. Evaluation of the use of common sculpin (Myoxocephalus scorpius) organ histology as bioindicator for element exposure in the fjord of the mining area Maarmorilik, West Greenland

    SciTech Connect (OSTI)

    Sonne, Christian; Bach, Lis; Søndergaard, Jens; Rigét, Frank F.; Dietz, Rune; Mosbech, Anders; Leifsson, Pall S.; Gustavson, Kim

    2014-08-15

    The former Black Angel lead–zinc mine in Maarmorilik, West Greenland, is a historic example of how mining activity may result in a significant impact on the surrounding fjord system in terms of elevated concentrations of especially lead (Pb) and zinc (Zn) in seawater, sediments and surrounding biota. In order to shed light on the present contamination and possible effects in the fjord we initiated a range of studies including a pilot study on gill and liver morphology of common sculpins (Myoxocephalus scorpius) around Maarmorilik. Sculpins were caught and sampled at five different stations known to represent a gradient of Pb concentrations. Fish livers from all specimens were analyzed for relevant elements in the area: Fe, Zn, As, Cu, Se, Cd, Pb, Ag, Hg, Co and Ni. Lead, As and Hg showed significant differences among the five stations. For 20% of the sculpins, Hg concentrations were in the range of lowest observed effect dose (LOED) of 0.1–0.5 μg/g ww for toxic threshold on reproduction and subclinical endpoints. Likewise LOEDs for tissue lesions, LOEDs for biochemistry, growth, survival and reproduction were exceeded for Cd (0.42–1.8 μg/g ww) and for As (11.6 μg/g ww) in 28% and 85% of the sculpins, respectively. Similar to this, the no observed effect dose (NOED) for biochemistry was exceeded for Pb (0.32 μg/g ww) and for growth, mortality and reproduction for Zn (60–68 μg/g ww) in 33% and 24% of the sculpins, respectively. For all sculpins, females were significantly larger than males and for five of the elements (Fe, Co, Ni, Cu, Se) females had higher concentrations. The chronic lesions observed in liver (mononuclear cell infiltrates, necrosis, vacuolar hepatocytes, portal fibrosis, bile duct hyperplasia, active melanomacrophage centers) and gills (fusion and edema of secondary lamellae, laminar telangiectasis, mononuclear cell infiltrates, blebs) were similar to those in the literature studies for both wild and laboratory exposed sculpins and

  1. User:GregZiebold/International Programs | Open Energy Information

    Open Energy Info (EERE)

    Strategy Inter-American Development Bank World Watch Institute (WWI) Grenada-Caribbean Solar Finance Program Organization of American States (OAS) Grenada-Pilot Program for...

  2. Greenland New Energy | Open Energy Information

    Open Energy Info (EERE)

    China Sector: Solar Product: China-based firm involved in silicon thin film solar cell technology. Coordinates: 31.966261, 119.472687 Show Map Loading map......

  3. OLADE-Latin American and Caribbean Energy Efficiency Seminar...

    Open Energy Info (EERE)

    Panama, Mexico, Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela, Barbados, Cuba, Grenada, Haiti, Jamaica,...

  4. Energy-Economic Information System (SIEE) | Open Energy Information

    Open Energy Info (EERE)

    Panama, Mexico, Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela, Barbados, Cuba, Grenada, Haiti, Jamaica,...

  5. OLADE Sustainable Energy Planning Manual | Open Energy Information

    Open Energy Info (EERE)

    Panama, Mexico, Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela, Barbados, Cuba, Grenada, Haiti, Jamaica,...

  6. Legal Energy Information System (SIEL) Database | Open Energy...

    Open Energy Info (EERE)

    Panama, Mexico, Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela, Barbados, Cuba, Grenada, Haiti, Jamaica,...

  7. Climate-Smart Agriculture Country Profiles | Open Energy Information

    Open Energy Info (EERE)

    featuredproductscsa-country-profiles Country: Argentina, Colombia, Costa Rica, El Salvador, Grenada, Mexico, Peru Cost: Free OpenEI Keyword(s): Agriculture, country profiles,...

  8. Sandia's ice sheet modeling of Greenland, Antarctica helps predict...

    National Nuclear Security Administration (NNSA)

    Wednesday, March 2, 2016 - 12:00am Sandia California researchers Irina Tezaur and Ray ... Read more. Related Topics California climate lanl Lawrence Berkeley National Laboratory ...

  9. Greenland Ice Sheet Modeling Update (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Conference: Regional Arctic System Model workshop ; 2014-06-04 - ... Sponsoring Org: DOELANL Country of Publication: United States Language: English Subject: ...

  10. Greenland Ice Sheet "Sliding" a Small Contributor to Future Sea...

    Office of Science (SC) Website

    A wide range of observations suggests that water generated by melt at the ice sheet ... vertical well-like shafts within a glacier through which water enters from the surface). ...

  11. Greenland Ice Sheet "Sliding" a Small Contributor to Future Sea...

    Office of Science (SC) Website

    ... by DOE's Office of Science under contract DE-AC02-05CH11231) and at Oak Ridge National Laboratory (supported by DOE's Office of Science under contract DE-AC05-00OR22725). ...

  12. Meltwater effects on flow of Greenland's ice sheet less severe...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    more to future sea-level rise than when considering the increases in melting alone," said co-author Stephen Price of the Los Alamos National Laboratory Climate Ocean and Sea...

  13. Green Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Name: Green Solar Place: Paris, France Zip: 45003 Product: Develops and builds PV systems in Guadeloupe and Mauritius. Coordinates: 48.85693,...

  14. Clay Minerals Related To The Hydrothermal Activity Of The Bouillante...

    Open Energy Info (EERE)

    Minerals Related To The Hydrothermal Activity Of The Bouillante Geothermal Field (Guadeloupe) Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

  15. ORAU Team

    Broader source: Energy.gov (indexed) [DOE]

    ... include Callaway, Falaya- Collins complex, Grenada, Loring, ... County, Kentucky 2.3% 3.2% 312, McCracken County, Kentucky ... of the Interior, Denver, Colorado, November 1, http:...

  16. New Method Relates Greenland Ice Sheet Changes to Sea-Level Rise...

    Office of Science (SC) Website

    Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo jpg image, 244418 bytes Image courtesy of NASA Earth Observatory via a Creative Commons ...

  17. Update on Greenland Ice Sheet Simulations In CISM and CESM (Conference...

    Office of Scientific and Technical Information (OSTI)

    Authors: Lipscomb, William Henry 1 + Show Author Affiliations Los Alamos National Laboratory Publication Date: 2016-02-12 OSTI Identifier: 1238137 Report Number(s): ...

  18. Energy Transition Initiative: Island Energy Snapshot - Dominica (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2015-03-01

    This profile provides a snapshot of the energy landscape of the Commonwealth of Dominica, an island nation located southeast of Guadeloupe and northwest of Martinique in the Lesser Antilles.

  19. November

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Laboratory, won an R&D 100 Award. - 112015 Greenland ice loss. New climate model predicts likelihood of Greenland ice melt, sea level rise and dangerous temperatures A...

  20. Washington County, Arkansas: Energy Resources | Open Energy Informatio...

    Open Energy Info (EERE)

    Farmington, Arkansas Fayetteville, Arkansas Goshen, Arkansas Greenland, Arkansas Johnson, Arkansas Lincoln, Arkansas Prairie Grove, Arkansas Springdale, Arkansas Tontitown,...

  1. ARM - Facility News Article

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    8, 2012 [Data Announcements, Facility News] New Data from Greenland for Arctic Climate Research Bookmark and Share Instruments for ICECAPS operate on top and inside of the Mobile Science Facility at Summit Station in Greenland. Instruments for ICECAPS operate on top and inside of the Mobile Science Facility at Summit Station in Greenland. In 2010, researchers installed a powerful suite of climate and weather instruments at Greenland's frozen research outpost, Summit Station, for a long-term

  2. December

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory depicts sea surface temperatures around Greenland from October 2010. Effect of ocean temperature on southwestern U.S. climate analyzed Researchers concluded...

  3. NERSC Supercomputers Help Explain the Last Big Freeze

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Atlantic (near Greenland), allowing it to disrupt the ocean's heat engine. "With 18 kilometers between each grid-point, we have the highest resolution ocean model in paleoclimate....

  4. Rockingham County, New Hampshire: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    New Hampshire Derry, New Hampshire East Kingston, New Hampshire Epping, New Hampshire Exeter, New Hampshire Fremont, New Hampshire Greenland, New Hampshire Hampstead, New...

  5. Effect of ocean temperature on southwestern U.S. climate analyzed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    depicts sea surface temperatures around Greenland from October 2010. Assuming that the past is a good indicator of the future, the scientists conclude that there should be...

  6. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    advances understanding of the Greenland Ice Sheet's meltwater channels October 1, 2014 EMBARGOED FOR RELEASE: Wednesday, Oct. 1, 2014, 1 p.m. ET LOS ALAMOS, N.M., Oct. 1, 2014-An international research team's field work, drilling and measuring melt rates and ice sheet movement in Greenland is showing that things are, in fact, more complicated than we thought. "Although the Greenland Ice Sheet initially speeds up each summer in its slow-motion race to the sea, the network of meltwater

  7. LMS-AMC-S01980-0-0.cdr

    Office of Legacy Management (LM)

    1965-2005 Year Pollock Pacific Cod Sable Fish Yellow Fin Sole Greenland Turbot Arrow Tooth Flounder a Rock Sole c Other Flat Fish Alaska Plaice Pacific Ocean Complex b Pacific ...

  8. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The Greenland and Antarctic ice sheets will make a dominant contribution to twenty-first century sea-level rise if current climate trends continue, studied in a five-year project ...

  9. Sandia National Laboratories:

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    05, 2016 Articles Nondestructive Testing Nondestructive Testing: Sandia looks inside composites Sandia takes home three national tech transfer awards Decon, bombs, and above and beyond Sandians win Black Engineer of the Year awards Sandians win Black Engineer of the Year awards Ice sheet modeling of Greenland, Antarctica helps predict sea-level rise Ice sheet modeling of Greenland, Antarctica helps predict sea-level rise Making waves Making waves Grid modernization Grid modernization New Mexico

  10. Oak Ridge National Laboratory | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Oak Ridge National Laboratory A snapshot of NNSA's counterterrorism mission NNSA's mission of counterterrorism and counterproliferation is supported through innovative science and technology. Recently, Associate Administrator and Deputy Undersecretary for Counterterrorism and Counterproliferation Jay Tilden visited Oak Ridge National Laboratory (ORNL) and met with... Sandia's ice sheet modeling of Greenland, Antarctica helps predict sea-level rise The Greenland and Antarctic ice sheets will make

  11. climate | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    climate NNSA labs fight fire with simulation Fire season is in full swing in the driest parts of the United States, and capabilities of NNSA's labs are helping equip firefighters in the heated battle to save property and environment. NNSA's labs are perfectly suited to support emergency response related to fire. A long history of... Sandia's ice sheet modeling of Greenland, Antarctica helps predict sea-level rise The Greenland and Antarctic ice sheets will make a dominant contribution to 21st

  12. ornl | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    ornl A snapshot of NNSA's counterterrorism mission NNSA's mission of counterterrorism and counterproliferation is supported through innovative science and technology. Recently, Associate Administrator and Deputy Undersecretary for Counterterrorism and Counterproliferation Jay Tilden visited Oak Ridge National Laboratory (ORNL) and met with... Sandia's ice sheet modeling of Greenland, Antarctica helps predict sea-level rise The Greenland and Antarctic ice sheets will make a dominant contribution

  13. clothiaux-98.pdf

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    climate NNSA labs fight fire with simulation Fire season is in full swing in the driest parts of the United States, and capabilities of NNSA's labs are helping equip firefighters in the heated battle to save property and environment. NNSA's labs are perfectly suited to support emergency response related to fire. A long history of... Sandia's ice sheet modeling of Greenland, Antarctica helps predict sea-level rise The Greenland and Antarctic ice sheets will make a dominant contribution to 21st

  14. ARM - Facility News Article

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    10, 2010 [Facility News] Supporting Science at Summit Station, Greenland Bookmark and Share This month, an ARM micropulse lidar and ceilometer began collecting data from Summit Station in Greenland as part of the ICECAPS field campaign that runs through October 2014. Scientist Matthew Shupe joined colleagues on location to install the ICECAPS mobile laboratory, documenting their progress through his field blog. Great job, Matt! Visit the campaign website for more information

  15. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    climate model predicts likelihood of Greenland ice melt, sea level rise and dangerous temperatures November 20, 2015 LOS ALAMOS, N.M., Nov. 16, 2015-A new computer model of accumulated carbon emissions predicts the likelihood of crossing several dangerous climate change thresholds. These include global temperature rise sufficient to lose the Greenland Ice Sheet and generate seven meters of long-term sea level rise, or tropical region warming to a level that is deadly to humans and other

  16. ovtchinnikov-98.pdf

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ornl A snapshot of NNSA's counterterrorism mission NNSA's mission of counterterrorism and counterproliferation is supported through innovative science and technology. Recently, Associate Administrator and Deputy Undersecretary for Counterterrorism and Counterproliferation Jay Tilden visited Oak Ridge National Laboratory (ORNL) and met with... Sandia's ice sheet modeling of Greenland, Antarctica helps predict sea-level rise The Greenland and Antarctic ice sheets will make a dominant contribution

  17. ARM - Feature Stories and Releases Article

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3, 2013 [Facility News, Feature Stories and Releases] Cloud Cocktail Melts Greenland Ice Sheet Bookmark and Share Like the partygoer that just won't leave, low-level clouds hang around and cause temperatures to rise Not all clouds are created equal-especially in the Arctic. New research published in the journal Nature shows that low-level clouds in Greenland that contain just the right amount of water are thick enough to block heat from escaping to space, but thin enough to allow sunlight to

  18. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Meltwater effects on flow of Greenland's ice sheet less severe for sea level rise than earlier feared, scientists say August 19, 2013 LOS ALAMOS, N.M., Aug. 19, 2013-The effects of increased melting on the future motion of and sea-level contribution from Greenland's massive ice sheet are not quite as dire as previously thought, according to a new study from an international team of researchers. In a paper published this month in Proceedings of the National Academy of Sciences (PNAS), the team

  19. Airborne reconnaissance VIII; Proceedings of the meeting, San Diego, CA, August 21, 22, 1984

    SciTech Connect (OSTI)

    Henkel, P.; Lagesse, F.R.

    1984-01-01

    Various papers on sensors and ancillary equipment, technological advances, development and testing, and intelligence extraction and exploitation in airborne reconnaissance are presented. The topics discussed include: the CA-810 modern trilens camera, PC-183B standoff imaging system, ruggedized MMW radiometer sensor for surveillance applications, application of biocular viewers to airborne reconnaissance, KA-102 film/EO standoff system, KS-146A camera development and flight test results, electrooptical imaging for film cameras, and new generation advanced IR linescan sensor system. Also addressed are: evolution of real time airborne reconnaissance, computer-controlled operation of reconnaissance cameras, miniature focus sensor, microprocessor-controller autofocus system, camera flight tests and image evaluation, LM-230A cost-effective test system, information management for tactical reconnaissance, performance modeling of infrared linescanners and FLIRs, USAF tactical reconnaissance - Grenada, sensor control and film annotation for long-range standoff reconnaissance, laser beam recording on film, meteorological effects on image quality, and optimization of photographic information transfer by CRT.

  20. Mesozoic-Cenozoic paleographic evolution of Northern South America

    SciTech Connect (OSTI)

    Pindell, J. )

    1993-02-01

    A model for northern South American tectonic and stratigraphic evolution is presented in 14 detailed, palinspastic, paleogeographic plates showing paleosedimentation and paletectonic data. Main deformational, depositional, and basin forming events along with HC maturation/migration are outlined in relation to progressive tectonic evolution. A cause-and-effect relationship between Caribbean plate motions/associated basin development and hydrocarbon maturation and migration is clear. Triassic-Jurassic rifting from Yucatan/North America produced a northern segmented passive margin, and the Cocuy backarc basin in Colombia. To the west, at end Jurassic, a marginal seaway developed west of Central Cordillera which led to passive margin conditions along the Cocuy Basin/Central Cordillera, southward to Ecuador. The margin remained passive until Campanian, when Amaime-chaucha Terrane (leading edge of Caribbean crust) collided with east vergence (southwest-dipping subduction) with Central Cordillera, closing the marginal seaway. The Colon foredeep was thus established each of Central Cordillera; continued convergence occurred by east-dipping flat-slab subduction of Caribbean crust beneath Colombia. The northerly Caribbean crust continued eastward migration along north South America. Maastrichtian -Paleogene opening of Grenada Basin accomodated a southwest-direction of interplate thrusting of Lara Nappes, producing the north Maracaibo foredeep. Paleocene-Miocene sedimentation patterns record the eastward migration of (1) peripheral bulge uplift, (2) foredeep basin and oil kitchen, (3) allochthon emplacement, (4) erosion due to isostatic rebound caused by extension. Since Middle-Late Miocene, Maracaibo Block escaped northward from Eastern Cordillera convergence by >100 km, and the southeastern Caribbean region has become transtensional rather than transpressional.

  1. News Stories

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    News Stories News Stories Featured articles about DOE Office of Science programs and people at Los Alamos. Advanced Scientific Computing Greenland Ice Sheet "Sliding" a Small Contributor to Future Sea-Level Rise Awards Ten Los Alamos scientists, including four sponsored by the DOE Office of Science, honored by American Physical Society Los Alamos scientist Christopher Lee to receive DOE Office of Science Early Career Award Laboratory Chemist selected as the 2015 recipient of the F.

  2. Effect of ocean temperature on southwestern U.S. climate analyzed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    December » Effect of ocean temperature on southwestern climate Effect of ocean temperature on southwestern U.S. climate analyzed Researchers concluded that only part of the recent temperature rise in the Southwest could be attributed to greenhouse gases. December 19, 2013 Image from National Oceanic and Atmospheric Administration's Environmental Visualization Laboratory depicts sea surface temperatures around Greenland from October 2010. Image from National Oceanic and Atmospheric

  3. PISCEES for prediction

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    PISCEES for prediction PISCEES for prediction The Greenland and Antarctic ice sheets will make a dominant contribution to twenty-first century sea-level rise if current climate trends continue, studied in a five-year project called Predicting Ice Sheet and Climate Evolution at Extreme Scales (PISCEES) February 19, 2016 Human-gorilla divergence may have occurred two million years earlier than thought (Photo : Flickr: Rod Waddington) Antarctica "The data we get from climate scientists are

  4. Microsoft PowerPoint - 06_ARM_AWG_Lacis_2007.ppt [Compatibility Mode]

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Geoengineering: Geoengineering: Plan B Remedy for Global Warming y g Andy Lacis Aerosol Working Group 26 March 2007 Some Radiative Aspects of Proposed Geoengineering Countermeasures to Global Warming (submitted to PNAS) g ( ) Andrew A. Lacis, Jennifer L. Alltop, Solomon M. Hsiang, Kirk D. Knobelspiesse, Jing Li, Cindy B. Pearl Accelerated melting of Greenland ice due to global warming . . . How can aerosols be used to counteract global warming? * Injection of sulfur into the lower stratosphere *

  5. Effect of ocean temperature on southwestern U.S. climate analyzed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Effect of ocean temperature on southwestern climate Effect of ocean temperature on southwestern U.S. climate analyzed Researchers concluded that only part of the recent temperature rise in the Southwest could be attributed to greenhouse gases. December 19, 2013 Image from National Oceanic and Atmospheric Administration's Environmental Visualization Laboratory depicts sea surface temperatures around Greenland from October 2010. Image from National Oceanic and Atmospheric Administration's

  6. Science Briefs - 2013

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Briefs - 2013 Read in detail about specific Los Alamos science achievements, and the honors our scientists are accruing. Image from National Oceanic and Atmospheric Administration's Environmental Visualization Laboratory depicts sea surface temperatures around Greenland from October 2010. Effect of ocean temperature on southwestern U.S. climate analyzed Researchers concluded that only part of the recent temperature rise in the Southwest could be attributed to greenhouse gases. -

  7. Latitudinal distribution of the recent Arctic warming

    SciTech Connect (OSTI)

    Chylek, Petr; Lesins, Glen K; Wang, Muyin

    2010-12-08

    Increasing Arctic temperature, disappearance of Arctic sea ice, melting of the Greenland ice sheet, sea level rise, increasing strength of Atlantic hurricanes are these impending climate catastrophes supported by observations? Are the recent data really unprecedented during the observational records? Our analysis of Arctic temperature records shows that the Arctic and temperatures in the 1930s and 1940s were almost as high as they are today. We argue that the current warming of the Arctic region is affected more by the multi-decadal climate variability than by an increasing concentration of carbon dioxide. Unfortunately, none of the existing coupled Atmosphere-Ocean General Circulation Models used in the IPCC 2007 cIimate change assessment is able to reproduce neither the observed 20th century Arctic cIimate variability nor the latitudinal distribution of the warming.

  8. Time varying arctic climate change amplification

    SciTech Connect (OSTI)

    Chylek, Petr; Dubey, Manvendra K; Lesins, Glen; Wang, Muyin

    2009-01-01

    During the past 130 years the global mean surface air temperature has risen by about 0.75 K. Due to feedbacks -- including the snow/ice albedo feedback -- the warming in the Arctic is expected to proceed at a faster rate than the global average. Climate model simulations suggest that this Arctic amplification produces warming that is two to three times larger than the global mean. Understanding the Arctic amplification is essential for projections of future Arctic climate including sea ice extent and melting of the Greenland ice sheet. We use the temperature records from the Arctic stations to show that (a) the Arctic amplification is larger at latitudes above 700 N compared to those within 64-70oN belt, and that, surprisingly; (b) the ratio of the Arctic to global rate of temperature change is not constant but varies on the decadal timescale. This time dependence will affect future projections of climate changes in the Arctic.

  9. Laurentide Ice Sheet meltwater and abrupt climate change during the last glaciation

    SciTech Connect (OSTI)

    Hill, H W; Flower, B P; Quinn, T M; Hollander, D J; Guilderson, T P

    2005-10-02

    A leading hypothesis to explain abrupt climate change during the last glacial cycle calls on fluctuations in the margin of the North American Laurentide Ice Sheet (LIS), which may have routed freshwater between the Gulf of Mexico (GOM) and North Atlantic, affecting North Atlantic Deep Water (NADW) variability and regional climate. Paired measurements of {delta}O and Mg/Ca of foraminiferal calcite from GOM sediments reveal five episodes of LIS meltwater input from 28-45 thousand years ago (ka) that do not match the millennial-scale Dansgaard-Oeschger (D/O) warmings recorded in Greenland ice. We suggest that summer melting of the LIS may occur during Antarctic warming and likely contributed to sea-level variability during Marine Isotope Stage 3 (MIS 3).

  10. A multi-model assessment of pollution transport to the Arctic

    SciTech Connect (OSTI)

    Shindell, D T; Chin, M; Dentener, F; Doherty, R M; Faluvegi, G; Fiore, A M; Hess, P; Koch, D M; MacKenzie, I A; Sanderson, M G; Schultz, M G; Schulz, M; Stevenson, D S; Teich, H; Textor, C; Wild, O; Bergmann, D J; Bey, I; Bian, H; Cuvelier, C; Duncan, B N; Folberth, G; Horowitz, L W; Jonson, J; Kaminski, J W; Marmer, E; Park, R; Pringle, K J; Schroeder, S; Szopa, S; Takemura, T; Zeng, G; Keating, T J; Zuber, A

    2008-03-13

    We examine the response of Arctic gas and aerosol concentrations to perturbations in pollutant emissions from Europe, East and South Asia, and North America using results from a coordinated model intercomparison. These sensitivities to regional emissions (mixing ratio change per unit emission) vary widely across models and species. Intermodel differences are systematic, however, so that the relative importance of different regions is robust. North America contributes the most to Arctic ozone pollution. For aerosols and CO, European emissions dominate at the Arctic surface but East Asian emissions become progressively more important with altitude, and are dominant in the upper troposphere. Sensitivities show strong seasonality: surface sensitivities typically maximize during boreal winter for European and during spring for East Asian and North American emissions. Mid-tropospheric sensitivities, however, nearly always maximize during spring or summer for all regions. Deposition of black carbon (BC) onto Greenland is most sensitive to North American emissions. North America and Europe each contribute {approx}40% of total BC deposition to Greenland, with {approx}20% from East Asia. Elsewhere in the Arctic, both sensitivity and total BC deposition are dominated by European emissions. Model diversity for aerosols is especially large, resulting primarily from differences in aerosol physical and chemical processing (including removal). Comparison of modeled aerosol concentrations with observations indicates problems in the models, and perhaps, interpretation of the measurements. For gas phase pollutants such as CO and O{sub 3}, which are relatively well-simulated, the processes contributing most to uncertainties depend on the source region and altitude examined. Uncertainties in the Arctic surface CO response to emissions perturbations are dominated by emissions for East Asian sources, while uncertainties in transport, emissions, and oxidation are comparable for European

  11. From Thule to Huli`s: Use of Magnetotellurics in difficult acquisition areas

    SciTech Connect (OSTI)

    Christopherson, K.R.

    1996-12-31

    Recent applications of Magnetotellurics have produced results superior to those of earlier years by many improvements in the technology, the application and, the interpretation of the method. MT continues to be useful in those areas where seismic acquisition is either difficult or expensive, where the surface inhibits effective seismic penetration, or where the use of MT is cost-effective as a predecessor to seismic. Improvements made to MT within the last few years include: multi-site acquisition with varied station spacings and omni-directional, low frequency antennae; smaller, higher storage field computers, sensor-box modifications for filtering unwanted signal (such as lightning); post-acquisition re-processing of the data via robust schemes; and faster, larger 2-D and 3-D modeling capabilities. Within the last two years, MT has been used world-wide for a variety of exploration targets. These include the continued use of MT for mapping subcarbonate plays in Papua New Guinea with on-going drilling. Here, use of seismic is precluded due to thick, high-velocity surface limestone. MT has been used as a precursor to seismic in overthrust regimes in Nevada and Colorado where MT is used to highgrade areas as prospects before seismic programs are acquired. In Greenland, MT has been used for reconnaissance mapping in large basin environments sub-basalt. On-going system modifications are being made to provide larger channel systems and future marine acquisition of MT.

  12. From Thule to Huli's: Use of Magnetotellurics in difficult acquisition areas

    SciTech Connect (OSTI)

    Christopherson, K.R. )

    1996-01-01

    Recent applications of Magnetotellurics have produced results superior to those of earlier years by many improvements in the technology, the application and, the interpretation of the method. MT continues to be useful in those areas where seismic acquisition is either difficult or expensive, where the surface inhibits effective seismic penetration, or where the use of MT is cost-effective as a predecessor to seismic. Improvements made to MT within the last few years include: multi-site acquisition with varied station spacings and omni-directional, low frequency antennae; smaller, higher storage field computers, sensor-box modifications for filtering unwanted signal (such as lightning); post-acquisition re-processing of the data via robust schemes; and faster, larger 2-D and 3-D modeling capabilities. Within the last two years, MT has been used world-wide for a variety of exploration targets. These include the continued use of MT for mapping subcarbonate plays in Papua New Guinea with on-going drilling. Here, use of seismic is precluded due to thick, high-velocity surface limestone. MT has been used as a precursor to seismic in overthrust regimes in Nevada and Colorado where MT is used to highgrade areas as prospects before seismic programs are acquired. In Greenland, MT has been used for reconnaissance mapping in large basin environments sub-basalt. On-going system modifications are being made to provide larger channel systems and future marine acquisition of MT.

  13. Albany/FELIX: A parallel, scalable and robust, finite element, first-order Stokes approximation ice sheet solver built for advanced analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tezaur, I. K.; Perego, M.; Salinger, A. G.; Tuminaro, R. S.; Price, S. F.

    2015-04-27

    This paper describes a new parallel, scalable and robust finite element based solver for the first-order Stokes momentum balance equations for ice flow. The solver, known as Albany/FELIX, is constructed using the component-based approach to building application codes, in which mature, modular libraries developed as a part of the Trilinos project are combined using abstract interfaces and template-based generic programming, resulting in a final code with access to dozens of algorithmic and advanced analysis capabilities. Following an overview of the relevant partial differential equations and boundary conditions, the numerical methods chosen to discretize the ice flow equations are described, alongmore » with their implementation. The results of several verification studies of the model accuracy are presented using (1) new test cases for simplified two-dimensional (2-D) versions of the governing equations derived using the method of manufactured solutions, and (2) canonical ice sheet modeling benchmarks. Model accuracy and convergence with respect to mesh resolution are then studied on problems involving a realistic Greenland ice sheet geometry discretized using hexahedral and tetrahedral meshes. Also explored as a part of this study is the effect of vertical mesh resolution on the solution accuracy and solver performance. The robustness and scalability of our solver on these problems is demonstrated. Lastly, we show that good scalability can be achieved by preconditioning the iterative linear solver using a new algebraic multilevel preconditioner, constructed based on the idea of semi-coarsening.« less

  14. Comparison of optically measured and radar-derived horizontal neutral winds. Master's thesis

    SciTech Connect (OSTI)

    Christie, M.S.

    1990-01-01

    Nighttime thermospheric winds for Sondrestrom, Greenland from 11 nights between 1983 and 1988, have been compared to learn about the O(+)-O collision cross section and the high-latitude atomic oxygen density. The horizontal winds in the magnetic meridian were derived indirectly from incoherent-scatter radar (ISR) measurements on ion velocities antiparallel to the magnetic field and directly from Fabry-Perot interferometer (FPI) measurements of Doppler shifts of the (6300-A) emission of atomic oxygen. In deriving the radar winds, the O(+)-O collision cross section, was scaled by a factor of f what was varied from 0.5 to 5.1. On the basis of several arguments the altitude of the 6300-A emission was assumed to be 230 km. The best agreement between the ISR and FPI winds was obtained when f was increased substantially, to between 1.7 and 3.4. If the average peak emission altitude were higher, these factors would be larger; if it were lower, they would be somewhat smaller. However, if the average altitude were substantially lower it would have been more difficult to have obtained agreement between the two techniques.

  15. Albany/FELIX: A parallel, scalable and robust, finite element, first-order Stokes approximation ice sheet solver built for advanced analysis

    SciTech Connect (OSTI)

    Tezaur, I. K.; Perego, M.; Salinger, A. G.; Tuminaro, R. S.; Price, S. F.

    2015-04-27

    This paper describes a new parallel, scalable and robust finite element based solver for the first-order Stokes momentum balance equations for ice flow. The solver, known as Albany/FELIX, is constructed using the component-based approach to building application codes, in which mature, modular libraries developed as a part of the Trilinos project are combined using abstract interfaces and template-based generic programming, resulting in a final code with access to dozens of algorithmic and advanced analysis capabilities. Following an overview of the relevant partial differential equations and boundary conditions, the numerical methods chosen to discretize the ice flow equations are described, along with their implementation. The results of several verification studies of the model accuracy are presented using (1) new test cases for simplified two-dimensional (2-D) versions of the governing equations derived using the method of manufactured solutions, and (2) canonical ice sheet modeling benchmarks. Model accuracy and convergence with respect to mesh resolution are then studied on problems involving a realistic Greenland ice sheet geometry discretized using hexahedral and tetrahedral meshes. Also explored as a part of this study is the effect of vertical mesh resolution on the solution accuracy and solver performance. The robustness and scalability of our solver on these problems is demonstrated. Lastly, we show that good scalability can be achieved by preconditioning the iterative linear solver using a new algebraic multilevel preconditioner, constructed based on the idea of semi-coarsening.

  16. Black carbon contribution to global warming

    SciTech Connect (OSTI)

    Chylek, P.; Johnson, B.; Kou, L.; Wong, J.

    1996-12-31

    Before the onset of industrial revolution the only important source of black carbon in the atmosphere was biomass burning. Today, black carbon production is divided between the biomass and fossil fuel burning. Black carbon is a major agent responsible for absorption of solar radiation by atmospheric aerosols. Thus black carbon makes other aerosols less efficient in their role of reflecting solar radiation and cooling the earth-atmosphere system. Black carbon also contributes to the absorption of solar radiation by clouds and snow cover. The authors present the results of black carbon concentrations measurements in the atmosphere, in cloud water, in rain and snow melt water collected during the 1992--1996 time period over the southern Nova Scotia. Their results are put into the global and historical perspective by comparing them with the compilation of past measurements at diverse locations and with their measurements of black carbon concentrations in the Greenland and Antarctic ice cores. Black carbon contribution to the global warming is estimated, and compared to the carbon dioxide warming, using the radiative forcing caused by the black carbon at the top of the atmosphere.

  17. A subtropical fate awaited freshwater discharged from glacial Lake Agassiz

    SciTech Connect (OSTI)

    Condron, Alan; Winsor, Peter

    2011-02-01

    The 8.2 kyr event is the largest abrupt climatic change recorded in the last 10,000 years, and is widely hypothesized to have been triggered by the release of thousands of kilometers cubed of freshwater into the North Atlantic Ocean. Using a high-resolution (1/6) global, ocean-ice circulation model we present an alternative view that freshwater discharged from glacial Lake Agassiz would have remained on the continental shelf as a narrow, buoyant, coastal current, and would have been transported south into the subtropical North Atlantic. The pathway we describe is in contrast to the conceptual idea that freshwater from this lake outburst spread over most of the sub-polar North Atlantic, and covered the deep, open-ocean, convection regions. This coastally confined freshwater pathway is consistent with the present-day routing of freshwater from Hudson Bay, as well as paleoceanographic evidence of this event. Using a coarse-resolution (2.6) version of the same model, we demonstrate that the previously reported spreading of freshwater across the sub-polar North Atlantic results from the inability of numerical models of this resolution to accurately resolve narrow coastal flows, producing instead a diffuse circulation that advects freshwater away from the boundaries. To understand the climatic impact of freshwater released in the past or future (e.g. Greenland and Antarctica), the ocean needs to be modeled at a resolution sufficient to resolve the dynamics of narrow, coastal buoyant flows.

  18. The microbial fate of carbon in high-latitude seas: Impact of the microbial loop on oceanic uptake of CO{sub 2}

    SciTech Connect (OSTI)

    Yager, P.L.

    1996-12-31

    This dissertation examines pelagic microbial processes in high-latitude seas, how they affect regional and global carbon cycling, and how they might respond to hypothesized changes in climate. Critical to these interests is the effect of cold temperature on bacterial activity. Also important is the extent to which marine biological processes in general impact the inorganic carbon cycle. The study area is the Northeast Water (NEW) Polynya, a seasonally-recurrent opening in the permanent ice situated over the northeastern Greenland continental shelf. This work was part of an international, multi-disciplinary research project studying carbon cycling in the coastal Arctic. The first chapter describes a simple model which links a complex marine food web to a simplified ocean and atmosphere. The second chapter investigates the inorganic carbon inventory of the summertime NEW Polynya surface waters to establish the effect of biological processes on the air-sea pCO{sub 2} gradient. The third and fourth chapters use a kinetic approach to examine microbial activities in the NEW Polynya as a function of temperature and dissolved organic substrate concentration, testing the so-called Pomeroy hypothesis that microbial activity is disproportionately reduced at low environmental temperatures owing to increased organic substrate requirements. Together, the suite of data collected on microbial activities, cell size, and grazing pressure suggest how unique survival strategies adopted by an active population of high-latitude bacteria may contribute to, rather than detract from, an efficient biological carbon pump.

  19. On the origin of Laurentia

    SciTech Connect (OSTI)

    Dalziel, I.W.D. . Inst. for Geophysics)

    1992-01-01

    Laurentia, the Precambrian core of the North American continent, is surrounded by late Precambrian rift systems and therefore constitutes a suspect terrane''. A geometric and geological fit can be achieved between the Atlantic margin of Laurentia and the Pacific margin of the Gondwana craton. The enigmatic Arequipa massif along the southern Peruvian coast, that yields ca. 2.0 Ga radiometric ages, is juxtaposed with the Makkovik-Ketilidian province of the same age range in Labrador and southern Greenland. The Greenville belt continues beneath the ensialic Andes of the present day to join up with the 1.3--1.0 Ga San Ignacio and Sonsas-Aguapei orogens of the Transamazonian craton. Together with the recent identification of possible continuations of the Greenville orogen in East Antarctica and of the Taconic Appalachians in southern South America, the fit supports suggestions that Laurentia originated between East Antarctica-Australia and embryonic South America prior to the opening of the Pacific Ocean basin and amalgamation of the Gondwana Cordilleran and Appalachian margins, this implies that there may have been two supercontinents during the Neoproterozoic, before and after opening of the Pacific Ocean. As Laurentia and Gondwana appear to have collided on at least two occasions during the Paleozoic, this scenario therefore calls to question the existence of so-called supercontinental cycles. The Arica bight of the present day may reflect a primary reentrant in the South American continental margin that controlled subduction processes along the Andean margin and eventually led to uplift of the Altiplano.

  20. Iridium geochemistry of volcanic ash layers from the early Eocene rifting of the northeastern North Atlantic and some other Phanerozoic events

    SciTech Connect (OSTI)

    Schmitz, B.; Asaro, F. |

    1996-04-01

    This study shows that some types of explosive volcanism can result in significant Ir anomalies (up to 750 ppt); however, these are readily discerned from impact-related, extraterrestrial Ir amomalies by other chemical and mineralogical criteria. Iridium and major and trace elements were analyzed in 34 of the >180 volcanic ash layers in the Fur Formation of early Eocene age in Denmark. These ashes originate from explosive volcanism during rifting of the Greenland-Eurasia continent and subsequent sea-floor spreading in the young northeastern North Atlantic. In addition, 15 older Phanerozoic ashes, associated with other dramatic global events, have been analyzed for Ir. The Fur Formation ashes are unusually well preserved and have a wide compositional range - for example, rhyolitic, dacitic, tholeiitic and alkaline basaltic, mafic alkaline, and different salic alkaline ashes, and ashes with intermediate or unknown magma origin. Iridium shows a bimodal distribution, where all types of salic (alkaline as well as subalkaline) ashes have very low Ir concentrations (<50 ppt), similar to values for average continental crust, whereas all types of basaltic ashes show higher concentrations, generally in the range 70-450 ppt. A strongly alkaline, mafic (nephelinitic) ash holds 102{+-}29 ppt Ir. 97 refs., 5 figs., 8 tabs.

  1. Abrupt Climate Change and the Atlantic Meridional Overturning Circulation: sensitivity and non-linear response to Arctic/sub-Arctic freshwater pulses. Collaborative research. Final report

    SciTech Connect (OSTI)

    Hill, Christopher

    2015-06-15

    This project investigated possible mechanisms by which melt-water pulses can induce abrupt change in the Atlantic Meridional Overturning Circulation (AMOC) magnitude. AMOC magnitude is an important ingredient in present day climate. Previous studies have hypothesized abrupt reduction in AMOC magnitude in response to influxes of glacial melt water into the North Atlantic. Notable fresh-water influxes are associated with the terminus of the last ice age. During this period large volumes of melt water accumulated behind retreating ice sheets and subsequently drained rapidly when the ice weakened sufficiently. Rapid draining of glacial lakes into the North Atlantic is a possible origin of a number of paleo-record abrupt climate shifts. These include the Younger-Dryas cooling event and the 8,200 year cooling event. The studies undertaken focused on whether the mechanistic sequence by which glacial melt-water impacts AMOC, which then impacts Northern Hemisphere global mean surface temperature, is dynamically plausible. The work has implications for better understanding past climate stability. The work also has relevance for today’s environment, in which high-latitude ice melting in Greenland appears to be driving fresh water outflows at an accelerating pace.

  2. Non-stationary Return Levels of CMIP5 Multi-model Temperature Extremes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cheng, L.; Phillips, T. J.; AghaKouchak, A.

    2015-05-01

    The objective of this study is to evaluate to what extent the CMIP5 climate model simulations of the climate of the twentieth century can represent observed warm monthly temperature extremes under a changing environment. The biases and spatial patterns of 2-, 10-, 25-, 50- and 100-year return levels of the annual maxima of monthly mean temperature (hereafter, annual temperature maxima) from CMIP5 simulations are compared with those of Climatic Research Unit (CRU) observational data considered under a non-stationary assumption. The results show that CMIP5 climate models collectively underestimate the mean annual maxima over arid and semi-arid regions that are mostmore » subject to severe heat waves and droughts. Furthermore, the results indicate that most climate models tend to underestimate the historical annual temperature maxima over the United States and Greenland, while generally disagreeing in their simulations over cold regions. Return level analysis shows that with respect to the spatial patterns of the annual temperature maxima, there are good agreements between the CRU observations and most CMIP5 simulations. However, the magnitudes of the simulated annual temperature maxima differ substantially across individual models. Discrepancies are generally larger over higher latitudes and cold regions.« less

  3. Non-stationary Return Levels of CMIP5 Multi-model Temperature Extremes

    SciTech Connect (OSTI)

    Cheng, L.; Phillips, T. J.; AghaKouchak, A.

    2015-05-01

    The objective of this study is to evaluate to what extent the CMIP5 climate model simulations of the climate of the twentieth century can represent observed warm monthly temperature extremes under a changing environment. The biases and spatial patterns of 2-, 10-, 25-, 50- and 100-year return levels of the annual maxima of monthly mean temperature (hereafter, annual temperature maxima) from CMIP5 simulations are compared with those of Climatic Research Unit (CRU) observational data considered under a non-stationary assumption. The results show that CMIP5 climate models collectively underestimate the mean annual maxima over arid and semi-arid regions that are most subject to severe heat waves and droughts. Furthermore, the results indicate that most climate models tend to underestimate the historical annual temperature maxima over the United States and Greenland, while generally disagreeing in their simulations over cold regions. Return level analysis shows that with respect to the spatial patterns of the annual temperature maxima, there are good agreements between the CRU observations and most CMIP5 simulations. However, the magnitudes of the simulated annual temperature maxima differ substantially across individual models. Discrepancies are generally larger over higher latitudes and cold regions.

  4. Early Proterozoic transcontinental orogenic belts in the United States

    SciTech Connect (OSTI)

    Van Schmus, W.R. . Dept. of Geology); Bickford, M.E. . Dept. of Geology); Condie, K.C. . Dept. Geoscience)

    1993-02-01

    It has been recognized for many years that Early Proterozoic orogenic rocks in the western US range from 1.8 to 1.6 Ga, with a general distribution such that 1.8 to 1.7 Ga rocks underlie Colorado, northern Arizona, and northern New Mexico and 1.7 to 1.6 Ga rocks underlie southern Arizona and southern New Mexico. Recent U-Pb geochronologic and Sm-Nd isotopic studies by a variety of research groups have refined crustal history in the western region and have extended knowledge eastward into the buried midcontinent basement. As a result, the authors propose that 1.8 Ga to 1.6 Ga crust of the US by divided into two distinct, but overlapping, orogenic belts: a 1.8 to 1.7 Ga Inner Accretionary Belt and a 1.7 to 1.6 Ga Outer Tectonic Belt. The Inner Accretionary Belt (IAB) comprises rock suites with compositions and isotopic signatures compatible with origin as juvenile crustal terranes formed as oceanic or off-shore and related terranes that were accreted to southern Laurentia between 1.8 and 1.6 Ga. The IAB includes the Yavapai Province of Arizona, Early Proterozoic basement of Colorado and southern Wyoming, and the basement of Nebraska. The Mojave Province of California may be part of this belt, although it also includes components derived from older Proterozoic or Archean crust. Extension of the IAB eastward from Nebraska is uncertain at present, although coeval rocks that may be eastern manifestations of this 1.8 to 1.7 Ga orogenesis occur in Wisconsin (1.76 Ga granite-rhyolite suite), Ontario (Killarney granite), Labrador (Makkovic Province) and southern Greenland (Ketilidian orogen). The Outer Tectonic Belt (OTB) comprises rock suites which have compositions, structures, and isotopic signature compatible with origin in continental margin tectonic settings between 1.7 and 1.6 Ga.

  5. Multi-model Mean Nitrogen and Sulfur Deposition from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): Evaluation of Historical and Projected Future Changes

    SciTech Connect (OSTI)

    Lamarque, Jean-Francois; Dentener, Frank; McConnell, J.R.; Ro, C-U; Shaw, Mark; Vet, Robert; Bergmann, D.; Cameron-Smith, Philip; Dalsoren, S.; Doherty, R.; Faluvegi, G.; Ghan, Steven J.; Josse, B.; Lee, Y. H.; MacKenzie, I. A.; Plummer, David; Shindell, Drew; Skeie, R. B.; Stevenson, D. S.; Strode, S.; Zeng, G.; Curran, M.; Dahl-Jensen, D.; Das, S.; Fritzsche, D.; Nolan, M.

    2013-08-20

    We present multi-model global datasets of nitrogen and sulfate deposition covering time periods from 1850 to 2100, calculated within the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). The computed deposition fluxes are compared to surface wet deposition and ice-core measurements. We use a new dataset of wet deposition for 2000-2002 based on critical assessment of the quality of existing regional network data. We show that for present-day (year 2000 ACCMIP time-slice), the ACCMIP results perform similarly to previously published multi-model assessments. The analysis of changes between 1980 and 2000 indicates significant differences between model and measurements over the United States, but less so over Europe. This difference points towards misrepresentation of 1980 NH3 emissions over North America. Based on ice-core records, the 1850 deposition fluxes agree well with Greenland ice cores but the change between 1850 and 2000 seems to be overestimated in the Northern Hemisphere for both nitrogen and sulfur species. Using the Representative Concentration Pathways to define the projected climate and atmospheric chemistry related emissions and concentrations, we find large regional nitrogen deposition increases in 2100 in Latin America, Africa and parts of Asia under some of the scenarios considered. Increases in South Asia are especially large, and are seen in all scenarios, with 2100 values more than double 2000 in some scenarios and reaching >1300 mgN/m2/yr averaged over regional to continental scale regions in RCP 2.6 and 8.5, ~30-50% larger than the values in any region currently (2000). Despite known issues, the new ACCMIP deposition dataset provides novel, consistent and evaluated global gridded deposition fields for use in a wide range of climate and ecological studies.

  6. A subtropical fate awaited freshwater discharged from glacial Lake Agassiz

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Condron, Alan; Winsor, Peter

    2011-02-10

    The 8.2 kyr event is the largest abrupt climatic change recorded in the last 10,000 years, and is widely hypothesized to have been triggered by the release of thousands of kilometers cubed of freshwater into the North Atlantic Ocean. Using a high-resolution (1/6°) global, ocean-ice circulation model we present an alternative view that freshwater discharged from glacial Lake Agassiz would have remained on the continental shelf as a narrow, buoyant, coastal current, and would have been transported south into the subtropical North Atlantic. The pathway we describe is in contrast to the conceptual idea that freshwater from this lake outburstmore » spread over most of the sub-polar North Atlantic, and covered the deep, open-ocean, convection regions. This coastally confined freshwater pathway is consistent with the present-day routing of freshwater from Hudson Bay, as well as paleoceanographic evidence of this event. In this study, using a coarse-resolution (2.6°) version of the same model, we demonstrate that the previously reported spreading of freshwater across the sub-polar North Atlantic results from the inability of numerical models of this resolution to accurately resolve narrow coastal flows, producing instead a diffuse circulation that advects freshwater away from the boundaries. To understand the climatic impact of freshwater released in the past or future (e.g. Greenland and Antarctica), the ocean needs to be modeled at a resolution sufficient to resolve the dynamics of narrow, coastal buoyant flows.« less

  7. Collaborative research on the Northeast Water Polynya: NEWP92 hydrographic data report. USCGC Polar Sea cruise, July 15--August 15, 1992

    SciTech Connect (OSTI)

    Wallace, D.W.R.; Behrens, W.J.; Hopkins, T.S.; Kinder, C.; Deming, J.; Smith, W.O.; Top, Z.; Walsh, I.D.

    1995-06-01

    The Northeast Water Polynya (NEW) off the northeast coast of Greenland was the focus of two cruises aboard the USCGC Polar Sea during the summers of 1992 and 1993. The cruises were supported by the National Science Foundation Arctic Systems Science (ARCSS) program and were part of the Arctic Ocean Science Board`s International Arctic Polynya Program. The Polar Sea cruises were designed as multidisciplinary studies to test hypotheses about the mechanisms of heat, water and carbon flow within and beyond the boundaries of the polynya. Preliminary results of the 1992 study have been described elsewhere. A collection of papers arising from the 1992 cruise have been published in a Special Section of the Journal of Geophysical Research. This data report presents the hydrographic and basic chemical observations made from CTD/Rosette casts during the 1992 cruise. The station positions cruise are plotted in Figure 1. Also included in the report are selected section plots and vertical profiles. A total of 130 CTD casts were made during the cruise, measuring pressure, temperature, conductivity, dissolved oxygen, fluorescence and light transmission. Discrete samples were collected in 10-liter, rosette-mounted, Niskin bottles and analyzed, from most casts, for: salinity, dissolved nutrients, dissolved oxygen, anthropogenic halocarbons (e.g., Freon gases), pigments, particulate organic carbon and nitrogen. Suspended particulate matter was analyzed at selected stations and these data were used to calibrate the CTD-transmissometer. Samples were collected from selected stations and depths for tritium and helium analyses, carbonate chemistry, as well as for measurements of bacterial abundance.

  8. Evaluation of Preindustrial to Present-day Black Carbon and its Albedo Forcing from Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)

    SciTech Connect (OSTI)

    Lee, Y. H.; Lamarque, J.-F.; Flanner, M. G.; Jiao, C.; Shindell, Drew; Berntsen, T.; Bisiauxs, M.; Cao, J.; Collins, W. J.; Curran, M.; Edwards, R.; Faluvegi, G.; Ghan, Steven J.; Horowitz, L.; McConnell, J.R.; Ming, J.; Myhre, G.; Nagashima, T.; Naik, Vaishali; Rumbold, S.; Skeie, R. B.; Sudo, K.; Takemura, T.; Thevenon, F.; Xu, B.; Yoon, Jin-Ho

    2013-03-05

    As a part of the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), we evaluate the historical black carbon (BC) aerosols simulated by 8 ACCMIP models against the observations including 12 ice core records, a long-term surface mass concentrations and recent Arctic BC snowpack measurements. We also estimate BC albedo forcing by performing additional simulations using the NCAR Community Land and Sea-Ice model 4 with prescribed meteorology from 1996-2000, which includes the SNICAR BC-snow model. We evaluated the vertical profile of BC snow concentrations from these offline simulations to using recent BC snowpack measurements. Despite using the same BC emissions, global BC burden differs by approximately a factor of 3 among models due to the differences in aerosol removal parameterizations and simulated meteorology among models; 34 Gg to 103 Gg in 1850 and 82 Gg to 315 Gg in 2000. However,models agree well on 2.5~3 times increase in the global BC burden from preindustrial to present-day, which matches with the 2.5 times increase in BC emissions. We find a large model diversity at both NH and SH high latitude regions for BC burden and at SH high latitude regions for deposition fluxes. The ACCMIP simulations match the observed BC mass concentrations well in Europe and North America except at Jungfrauch and Ispra. However, the models fail to capture the Arctic BC seasonality due tosevere underestimations during winter and spring. Compared to recent snowpack measurements, the simulated vertically resolved BC snow concentrations are, on average, within a factor of 2-3 of observations except for Greenland and Arctic Ocean. However, model and observation differ widely due to missing interannual variations in emissions and possibly due to the choice of the prescribed meteorology period (i.e., 1996-2000).

  9. A CHRONOLOGICAL FRAMEWORK FOR THE HOLOCENE VEGETATIONAL HISTORY OF CENTRAL MINNESOTA: THE STEEL LAKE POLLEN RECORD

    SciTech Connect (OSTI)

    Wright, H E; Stefanova, I; Tian, J; Brown, T A; Hu, F S

    2003-11-10

    Paleorecords from Minnesota and adjacent areas have often been used to evaluate large-scale climatic processes in the mid-continent of North America. However, most of these records are compromised by chronological flaws, making problematic any comparisons with climatic interpretations based on other records (e.g., GISP2 in Greenland). We report here a high-resolution pollen record with a secure chronology constrained by 26 {sup 14}C dates on terrestrial macrofossils from Steel Lake, central Minnesota. About 11,200 years ago (calibrated yr BP) the late-glacial Picea forest near Steel Lake was succeeded abruptly by Pinus banksiana and/or resinosa. The Pinus forest began to open 9.4 ka cal BP with the expansion of prairie taxa, and a pine parkland or savanna prevailed until about 8 ka cal BP, when Quercus replaced Pinus to become the dominant tree in the prairie areas for 4500 years. The close chronological control permits the correlation of key vegetational changes with those at other reliably dated sites in the eastern Dakotas and in Minnesota, suggesting that the abrupt decline of the spruce forest was time-transgressive from southwest to northeast during 2000 years, and that the development of prairie was time-transgressive in the same direction over 2600 years. Correlation of key pollen horizons at Steel Lake with those in the high-resolution pollen profiles of Elk Lake, ca. 50 km northwest of Steel Lake, suggests that the well-known Elk Lake varve chronology for the early Holocene is about 1000 years too young.

  10. Climate data, analysis and models for the study of natural variability and anthropogenic change

    SciTech Connect (OSTI)

    Jones, Philip D.

    2014-07-31

    grid resolution is coarse (5° by 5° lat/long) the changes in storm activity are similar to those developed from the pressure triangle approach with station data. Analyses of humidity and pressure data In Simmons et al. (2010) we showed a reduction in relative humidity over low-latitude and mid-latitude land areas for the 10 years to 2008, based on monthly anomalies of surface air temperature and humidity from ECMWF reanalyses (ERA-40 and ERA-Interim) and our earlier land-only dataset (CRUTEM3) and synoptic humidity observations (HadCRUH). Updates of this station-based humidity dataset (now called HadISDH) extend the record, showing continued reductions (Willett et al., 2013). Analyses of Proxy Temperature Data In Vinther et al. (2010), relationships between the seasonal stable isotope data from Greenland Ice Cores and Greenland and Icelandic instrumental temperatures were investigated for the past 150-200 years. The winter season stable isotope data are found to be influenced by the North Atlantic Oscillation (NAO) and very closely related to SW Greenland temperatures. The summer season stable isotope data display higher correlations with Icelandic summer temperatures and North Atlantic SST conditions than with local SW Greenland temperatures. In Jones et al. (2014) we use these winter isotope reconstructions to show the expected inverse correlation (due to the NAO) with winter-season documentary reconstructions from the Netherlands and Sweden over the last 800 years. Finally, in this section Jones et al. (2013) shows the agreement between tree-ring width measurements from Northern Sweden and Finland and an assessment of the link to explosive volcanic eruptions. An instrumental record for the region in the early 19th century indicates that the summer of 1816 was only slightly below normal, explaining why this year has normal growth for both ring width and density. GCM/RCM/Reanalysis Evaluation In this section we have intercompared daily temperature extremes across

  11. The Arctic as a test case for an assessment of climate impacts on national security.

    SciTech Connect (OSTI)

    Taylor, Mark A.; Zak, Bernard Daniel; Backus, George A.; Ivey, Mark D.; Boslough, Mark Bruce Elrick

    2008-11-01

    organizations. Because changes in the Arctic environment are happening so rapidly, a successful program will be one that can adapt very quickly to new information as it becomes available, and can provide decision makers with projections on the 1-5 year time scale over which the most disruptive, high-consequence changes are likely to occur. The greatest short-term impact would be to initiate exploratory simulations to discover new emergent and robust phenomena associated with one or more of the following changing systems: Arctic hydrological cycle, sea ice extent, ocean and atmospheric circulation, permafrost deterioration, carbon mobilization, Greenland ice sheet stability, and coastal erosion. Sandia can also contribute to new technology solutions for improved observations in the Arctic, which is currently a data-sparse region. Sensitivity analyses have the potential to identify thresholds which would enable the collaborative development of 'early warning' sensor systems to seek predicted phenomena that might be precursory to major, high-consequence changes. Much of this work will require improved regional climate models and advanced computing capabilities. Socio-economic modeling tools can help define human and national security consequences. Formal uncertainty quantification must be an integral part of any results that emerge from this work.