2006 LAYERED OCEAN MODEL WORKSHOP

11:15 - 11:45 a.m. Tuesday February 14

Comparison of GFDL's HIM-based and MOM4-based coupled climate models

Robert Hallberg, Stephen Griffies, Matthew Harrison, and Michael Winton, NOAA/GFDL

GFDL scientists have developed two viable coupled climate models. One (CM2.1) uses the z-coordinate MOM4 as its ocean component, the other (CM2.2) uses the isopycnal-coordinate HIM, both at 1-degree horizontal resolution with roughly 50 vertical layers or levels. Because they share the same atmospheric, land, and sea ice components, the common and unique biases of these two models are particularly instructive of the ocean models' roles in the climate system. The SST biases, water mass structures, equatorial currents, and overturning circulations of the two models will be compared. Additionally, some of the changes that were made to HIM in developing it into a viable coupled climate model will be discussed.