Maxwell Kelley

Title:
Ocean Modeling at GISS: Challenges and Perspectives 

Abstract:
Covering >70% of the Earth's surface and having a spectrum of timescales ranging
from months to >1000 years, the ocean has long been recognized to play multiple 
roles in the climate system. The ability of ocean general circulation models
(OGCMs) to explore these roles has improved, but a number of challenges remain
in the construction of OGCMs suitable for coupled simulations on decadal to
millennial timescales. In the context of my recent experiences working with the
GISS OGCM, I will present examples of these issues, focusing primarily on their
impacts on the ocean's global temperature structure and its circulation metrics
at high latitudes, briefly examining ENSO variability and a climate-change
scenario as well. Specific exultations and lamentations will discuss 
(1) the stringent requirements on freshwater fluxes 
(2) the representation of unresolved transports 
(3) the importance of the details of bathymetry 
(4) the long timescales 
(5) differences between ocean-only and coupled ocean-atmosphere simulations 
(6) numerics