Coupled Parallel Climate Model (PCM) Applications to Climate Change
Warren M. Washington and Gerald A. Meehl, National Center for
Atmospheric Research
Albert Semtner, Naval Postgraduate School
John Weatherly, Cold Regions Research and Engineering Laboratory
Research Objectives
To conduct simulations of climate change with new generation high-resolution
climate models.
Computational Approach
The Parallel Climate Model (PCM) is a coupled climate model that
executes on the Cray T3E computer. The atmospheric component is
the National Center for Atmospheric Research (NCAR) Community
Climate Model; the ocean component is the Parallel Ocean Program
with a resolution of 32 levels and 2/3 degree horizontal grid;
and the sea ice component is the Naval Postgraduate School model
using a resolution of 27 km. The components are interfaced by
a flux coupler that passes the energy, moisture, and momentum
fluxes between components.
Accomplishments
Over the past year we were able to obtain a climate simulation
for the 1990s. We will use this control experiment for future
climate change scenarios with different forcings such as increasing
greenhouse gases and the effects of sulfate aerosols. This model
has higher-resolution ocean and sea ice components than are used
in previous coupled climate model simulations; thus we can see
much more realistic eddy structures in the ocean that are closer
to the observed patterns.
Significance
Because of an observed warming of the earth's climate that is probably caused by increased greenhouse gases, the Department of Energy is very interested in making better estimates of possible impacts on future states of climate. This requires, in part, better models of the climate system with improved resolution that provides regional impacts.
Publications
W. M. Washington and J. W. Weatherly, "Simulations
with a climate model with high-resolution ocean and sea ice,"
in Polar Processes and Global Climate: Draft Summary Report
from the Conference on Polar Processes and Global Climate, WMO/ICSU/IOC
World Climate Research Programme (WCRP) (International ACYSYS
Project Office, Oslo, Norway, 1997), pp. 250-252.