Deglaciation and latest Pleistocene and early Holocene glacier readvances on the Alaska Peninsula: Records of rapid climate change due to transient changes in solar intensity and atmospheric CO sub 2 content

Technical Report · Sun Mar 01 04:00:00 EST 1992

OSTI ID:7263777

Pinney, D S; Beget, J E

Geologic mapping near Windy Creek, Katmai National Park, identified two sets of glacial deposits postdating late-Wisconsin Iliuk moraines and separated from them by volcaniclastic deposits laid down under ice-free conditions. Radiocarbon dating of organic material incorporated in the younger Katolinat till and in adjacent peat and lake sediments suggests that alpine glaciers on the northern Alaska Peninsula briefly expanded between ca. 8500 and 10,000 years B.P. Stratigraphic relationships and radiocarbon dates suggest an age for the older Ukak drift near the Pleistocene-Holocene boundary between ca. 10,000 and 12,000 years B.P. The authors suggest that rapid deglaciation following deposition of the Iliuk drift occurred ca. 13,000-12,000 years B.P. in response to large increases in global atmospheric greenhouse gas content, including C02. Short-term decreases in these concentrations, as recorded in polar ice cores, may be linked with brief periods of glacier expansion during the latest Pleistocene and early Holocene. A transient episode of low solar intensity may also have occurred during parts of the early Holocene. Rapid environmental changes and glacial fluctuations on the Alaska Peninsula may have been in response to transient changes in the concentration of atmospheric greenhouse gases and solar intensity.

• Research Organization: Alaska Univ., College, AK (United States)
• OSTI ID: 7263777
• Report Number(s): AD-P-007351/0/XAB
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
540210 -- Environment
Terrestrial-- Basic Studies-- (1990-)
58 GEOSCIENCES
580000 -- Geosciences
AGE ESTIMATION
ALASKA
AMBIENT TEMPERATURE
CENOZOIC ERA
CLIMATIC CHANGE
DEPOSITION
DEVELOPED COUNTRIES
ENERGY SOURCES
ENVIRONMENTAL EFFECTS
FOSSIL FUELS
FUELS
GEOLOGIC AGES
GLACIERS
GREENHOUSE GASES
ICE
ISOTOPE DATING
LAKES
MAPPING
MATTER
MONITORING
NORTH AMERICA
ORGANIC MATTER
PALEOCLIMATOLOGY
PALEONTOLOGY
PEAT
QUATERNARY PERIOD
RADIATIONS
SEDIMENTS
SOLAR RADIATION
STELLAR RADIATION
SURFACE WATERS
USA
VOLCANOES