Seminar by Vishnu Nandan on April 1st, 2019

The Arctic is on the path to a new climate regime influenced by thinner first-year ice.  In contrast to Antarctic sea ice, Arctic cryosphere has recently undergone significant changes, highlighted by substantial decline in sea ice thickness, extensive loss of multi-year ice replaced by first-year ice, and decline in spring snow depth. These changes can significantly affect Arctic and mid-latitude climate, Arctic marine ecosystem, and directly impact the Arctic marine navigation. Satellite remote sensing has demonstrated its capability to derive estimates and trends of basin-scale Arctic sea ice thickness. These estimates are crucial to understanding recent variability and changes in Arctic sea ice. But are these estimates accurate and properly addressed?

 

This talk will provide a grassroot-level understanding on how satellites measure sea ice freeboard and thickness? To answer challenges faced by the sea ice science community to accurately estimate sea ice thickness, this talk will also focus on how snow cover on sea ice surface is a complex geophysical variable that critically impacts the accuracy of sea ice freeboard and thickness estimates from satellites. The talk will conclude with a few slides introducing our upcoming year-long expedition in the Central Arctic and our objective to use state-of-the-art remote sensing data to improve our fundamental understanding of the critical role of snow on accurate sea ice thickness retrievals.