WE PROPOSE TO CONTINUE A COLLABORATIVE AGREEMENT BETWEEN MIT AND THE NASA GODDARD INSTITUTE FOR SPACE SCIENCE (GISS) IN NEW YORK. THE PROGRAM BRINGS TOGETHER THE EXPERTISE OF MIT IN OCEAN DYNAMICS SEA-ICE AND OCEAN CLIMATE MODELING WITH THAT OF GISS IN COUPLED CLIMATE MODELING AND CLIMATE CHANGE. THE RESEARCH IS DIRECTED AT (I) HELPING TO COORDINATE OCEAN AND SEA-ICE MODELING ACTIVITIES AT GISS TO IMPROVE THE OCEAN COMPONENT OF MODELE GISS S COUPLED CLIMATE MODEL AND MITGCM (II) ENHANCING THE REPRESENTATION OF SEA-ICE PROCESSES IN MODELE AND (III) EVALUATING AND APPLYING THE NEW MODELS TO STUDY REGIONAL CLIMATE CHANGE IN THE ARCTIC. IN PARTICULAR THE MIT-GISS COLLABORATION WILL FOCUS ON: 1. DRIVING FORWARD DEVELOPMENT AND EVALUATION OF THE NEW GISS OCEAN MODEL KNOWN AS GO2 WITH A PARTICULAR EMPHASIS ON POLAR AND SEA-ICE PROCESSES 2. APPLYING THE NEW MODELS TO EXPLORE THE ROBUSTNESS OF THE COUPLED SYSTEM TO PERTURBATIONS IN THE ARCTIC IN THE CONTEXT OF ARCTIC CLIMATE RESPONSE FUNCTIONS. THE GISSMODEL-E DEPLOYED IN STUDIES OF CLIMATE CHANGE WILL PROVIDE THE MODELING CONTEXT BUT EXPERTISE IN OCEAN AND SEA-ICE MODELS DEVELOPED AT MIT WILL ALSO BE LEVERAGED. THIS PROPOSAL HARNESSES THE COMPLEMENTARY EXPERTISE OF JOHN MARSHALL (MIT) IN OCEAN DYNAMICS AND MODELING WITH THAT OF GAVIN SCHMIDT (GISS) IN SEA-ICE AND CLIMATE CHANGE PROCESSES. IT ALSO EXPANDS ONGOING COLLABORATIVE ACTIVITIES (REVIEWED BELOW) WITH DARREN ENGWIRDA THE POSTDOC SUPPORTED BY THE JUST-ENDING CURRENT COLLABORATIVE PROJECT. DARREN IS TO TAKE UP A RESEARCH SCIENTIST POSITION AT COLUMBIA UNIVERSITY AND SO WILL REMAIN A MEMBER OF THE TEAM. SUPPORT OF THIS PROPOSAL WOULD ENABLE US TO BRING IN NEW TALENT TO FOCUS ON THE CRITICAL ISSUE OF SEA-ICE MODELING AND DYNAMICS.