NA - Satellite Altimetry-Gravimetry Derived Geoid and Circulation of Ice-Covered Arctic and North Atlantic Oceans for Climate change Studies

The partners in this project have already started discussions within the framework of the "Working Title". This cooperation will result in a joint project within the framework of the proposed title in this application. However, the "Working Title" could b e supplemented with the additional information at the end of this project. It is discussed the possibility of inclusion of at least one PhD student and one Post-doc candidate, in addition to the principle investigators, in the new project. Both partners (OSU and UCA) are very well-known scientists in the relevant disciplines of satellite altimetry, gravity field, ocean tides, and ocean model constrain studies. Project manager is a specialist within gravity field modeling and satellite altimetry with two other NFR funded project: Professor Nahavandchi is the project manger of NFR funded project with project number 147618 and also the PI (working group leader) of another NFR funded project with project number 155835/700. In modern climate, ocean circula tion is responsible for the heat transport. It has been widely accepted that the Arctic is sensitive to climate variability and is in the midst of a major climate, environmental change and sea ice and tickness changes remain an important indicator and a f orcing mechanism for climate and environmental change. While sea-ice thickness change is the ultimate observation, its computation from freeboard height change and from satellite altimetry is limited, in addition to ice motion, ice concentration and ice e xtent, by our knowledge of geoid (and its gradients), ocean tides beneath the sea ice, and ocean circulation (consists of the quasi-stationary dynamic topography and its variability). Determination of accurate geoid information in sea ice covered regions using GRACE twin satellites , the Arctic Gravity Project and altimtery data together with the analysis of ocean tide models are essential for the determination of ice sea freeboard height and sea ice thicknes