Document: TIM-3-66-24

Once and future climates of the conterminous United States: Spatial-temporal variability in the VEMAP2 historical and scenario bioclimate dataset.

KITTEL, T.G.F.* ¹, D.NYCHKA ¹, N.ROSENBLOOM ¹, S.AULENBACH ¹, C.KAUFMAN ¹, D.YATES ¹, D.SCHIMEL ², D.OJIMA ³, C.DALY ⁴, J.A.ROYLE ⁵ and VEMAP MEMBERS ⁶

National Center for Atmospheric Research, Boulder CO 80307 USA ¹
Max-Planck-Institute for Biogeochemistry, Jena, Germany ²
Colorado State University, Ft. Collins, CO 80523 USA ³
Oregon State University, Corvallis, OR 97333 USA ⁴
US Fish and Wildlife Service, Laurel MD USA ⁵
Vegetation/Ecosystem Modeling and Analysis Project ⁶

Abstract:
Climate varies across continental regions in characteristic spatial and temporal patterns that strongly influence vegetation dynamics and biogeochemical processes, such as disturbance regimes and carbon storage. The Vegetation/Ecosystem Modeling and Analysis Project (VEMAP) Phase 2 historical and future scenario climate dataset for the conterminous US was developed as inputs for the simulation of vegetation and ecosystem dynamics over the period 1895-2100, with future climates derived from coupled climate model experiments. To understand the nature of the driving climates for ecological simulations, we evaluated spatial-temporal variability in seasonal thermal and moisture parameters (e.g., minimum and maximum temperature, precipitation, Palmer Drought Severity Index, growing-degree days). During the historical period, thermal variables exhibited spatially-extensive (often dipolar) oscillations across the conterminous US at interannual and decadal time scales. Precipitation variability regimes were also prominent, but with characteristically shorter spatial scales and were more complex in time and space. 21st century climates, while dominated by trends in the means (driven by enhanced greenhouse gas and sulfate aerosol forcings), exhibited strong patterns of spatial and temporal variability that were altered from those of the historical period.

Keywords: Climate Change, Vegetation Modeling, Ecosystem Modeling, United States

This abstract is being presented at: 3:45 PM in session:
Oral Session #66: Large Scale Climate Change.