Present-Day Atmospheric Simulations Using GISS ModelE: Comparison to In Situ, Satellite, and Reanalysis Data

TLDR

The study presents a full description of the GISS ModelE atmospheric general circulation model and its results for present‑day climate simulations. The authors implemented a complete rewrite of the GISS GCM, adding higher vertical resolution, a cloud microphysics scheme, humidity‑sensitive vegetation biophysics, full‑column turbulence, and updated land snow and lake schemes, and evaluated three horizontal/vertical configurations against in‑situ, satellite, and reanalysis data. The updated ModelE shows marked improvements in upper‑atmosphere temperatures, winds, cloud heights, precipitation, and sea‑level pressure, yet still struggles with marine stratocumulus representation. The study references data from 1979.

Abstract

Abstract A full description of the ModelE version of the Goddard Institute for Space Studies (GISS) atmospheric general circulation model (GCM) and results are presented for present-day climate simulations (ca. 1979). This version is a complete rewrite of previous models incorporating numerous improvements in basic physics, the stratospheric circulation, and forcing fields. Notable changes include the following: the model top is now above the stratopause, the number of vertical layers has increased, a new cloud microphysical scheme is used, vegetation biophysics now incorporates a sensitivity to humidity, atmospheric turbulence is calculated over the whole column, and new land snow and lake schemes are introduced. The performance of the model using three configurations with different horizontal and vertical resolutions is compared to quality-controlled in situ data, remotely sensed and reanalysis products. Overall, significant improvements over previous models are seen, particularly in upper-atmosphere temperatures and winds, cloud heights, precipitation, and sea level pressure. Data–model comparisons continue, however, to highlight persistent problems in the marine stratocumulus regions.