Tuesday, 11 January 2005: 1:30 PM
The GSWP2 baseline simulations: summary evaluation
Considerable attention in the past decade has focused on the importance of the land surface, its (potential) influence on climate predictability and prediction, and the ability of our prediction systems to faithfully reproduce these aspects of the climate system. For the first time, a multi-model set of simulations at the global scale have been executed that can provide simulated land states and fluxes for comparison and evaluation. For the baseline simulations of the Global Soil Wetness Project Phase 2 (GSWP 2), global land model simulations at a 1x1 degree resolution, spanning the years 1986-1995, have been performed in "standalone mode" with prescribed atmospheric conditions (based on the ISLSCP II Initiative Data). In this analysis, a summary of some of the more significant aspects of the land model simulations will be presented. Among the diagnostics presented that evaluate the model simulations will be: memory (i.e. auto-correlation) of water storages, the inter-annual variability of snow cover and storage; and global estimates of evaporation and runoff (within the context of a global water budget synthesis). The overall strategy of this particular analysis is to: 1) identify consistency (if any) among the models and 2) determine its veracity. For this presentation, the summary evaluation will largely address the model consistency issue, although observations will be employed as much as possible. Utlimately, through evaluation of these baseline simulations (as well as further sensitivity simulations) the GSWP 2 evaluation effort aims to achieve a benchmark of the current capabilities of "state of the art" land surface models, their potential to faithfully harvest (coupled) predictability in the global hydroclimatic system, and thus their degree of skill and confidence in climate predictions and climate-change projections.