Regional climate change scenarios over the United States produced with a nested regional climate model

Journal Article · Tue Mar 01 04:00:00 EST 1994 · Journal of Climate; (United States)

DOI:https://doi.org/10.1175/1520-0442(1994)007<0375:RCCSOT>2.0.CO;2· OSTI ID:7266037

Giorgi, F; Brodeur, C S; Bates, G T ^[1]

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1. National Center for Atmospheric Research, Boulder, CO (United States)

Two continuous 31/2-year-long climate simulation over the continental United States are discussed, one of present-day conditions and one for conditions under double carbon dioxide concentration, conducted with a limited area model (LAM) nested in a general circulation model (GCM). The models used are a version of the NCAR Community Climate Model (CCM) at rhomboidal 15 spectral resolution and the climate version of the NCAR/Penn State mesoscale model (MM4) at 60-km gridpoint spacing. For present-day conditions the model temperatures are within 1[degrees]-2[degrees]C of observations except over the Great Lakes region, where temperature is overpredicted. The CCM overpredicts precipitation throughout the continental United States (overall by about 60%) and especially over the West (by up to 300%). The nested MM4 overpredicts precipitation over the West but underpredicts it over the eastern United States. In addition, it produces a large amount of topographically and lake-induced sub-GCM grid-scale detail that compares well with available high-resolution climate data. Overall, the nested MM4 reproduces observed spatial and seasonal precipitation patterns better than the driving CCM. Doubled carbon dioxide-induced temperature change scenarios produced by the two models generally differ by less than several tenths of a degree except over the Great Lakes region where, because of the presence of the lakes in the nested model, the two model scenarios differ by more than one degree. Conversely, precipitation change scenarios from the two model simulations can locally differ in magnitude, sign, spatial, and seasonal detail. These differences are associated with topographical features in the MM4, such as the presence of steep coastal ranges in the western United States. This work illustrates the feasibility of the use of the nested modeling technique for long-term regional climate simulation. 43 refs., 19 figs., 6 tabs.

• OSTI ID: 7266037
• Journal Information: Journal of Climate; (United States), Journal Name: Journal of Climate; (United States) Vol. 7:3; ISSN JLCLEL; ISSN 0894-8755
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring &amp; Transport-- (1990-)
AMBIENT TEMPERATURE
ATMOSPHERIC PRECIPITATIONS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CLIMATE MODELS
CLIMATIC CHANGE
DEVELOPED COUNTRIES
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL EFFECTS
GENERAL CIRCULATION MODELS
MATHEMATICAL MODELS
NORTH AMERICA
OXIDES
OXYGEN COMPOUNDS
USA