Abstracts of oral and poster sessions
The climate model of the Goddard Institute for Space Studies (GISS GCM) has been used to project the influence of increasing concentrations of greenhouse gases on the future global climate. New parameterizations for the GISS GCM are being developed to improve its depiction of current climate scenarios and to make it more sensitive to the variability of external forcing mechanisms such as sea-surface temperatures (SST), atmospheric aerosols and constituent trace gases. The new moist convection scheme makes cumulus fluxes proportional to vertical thermal instability and computes convective-scale downdrafts whose effect is to prevent excessive drying of the boundary layer by compensating subsidence. The physically-based ground hydrology component improves the land surface sensible and latent heat calculations by explicitly considering transpiration, evaporation from intercepted precipitation, evaporation from bare soil, infiltration, soil water flow and runoff. The revised planetary boundary layer uses a more valid physical model than previously to obtain more realistic near-surface winds and energy budgets. Preliminary results with newer versions of the GCM include a better seasonal migration of the ITCZ and more realistic tropical winds. One of our approaches to model validation is the evaluation of runs forced by globally observed sea-surface temperatures. The presentation will show how model improvements increase the quality of simulated interannual variations in global circulation and tropical rainfall.
- Research Organization:
- Columbia Univ., New York, NY (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- FG02-92ER61477
- OSTI ID:
- 67260
- Report Number(s):
- CONF-9407181-Absts.; ON: DE95011951
- Resource Relation:
- Conference: European conference on the global energy and water cycle, London (United Kingdom), 18-22 Jul 1994; Other Information: PBD: [1994]
- Country of Publication:
- United States
- Language:
- English
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