Ekman Transport and Upwelling in the Arctic Ocean


Arctic Research Initiative
2008 Funded Project


The Ekman pumping/sucking (downwelling/upwelling) is one of the most important variables in the study of oceanography, especially the ocean circulation, nutrient and tracer transports, etc.  Variability in the ocean can often be explained by variations of the Ekman pumping.  But there has been no publicly accessible dataset of Ekman transport and pumping over the ice-covered Arctic Ocean.  This is largely due to the lack of a good-quality and basin-wide observational dataset of sea-ice drift speed that is used in estimating ice-water stress.  The situation has changed in recent years.  Some newly developed algorithms are now capable of retrieving ice motion data from satellite AVHRR, SMMR and SSMI data.  The PI has taken advantage of a new dataset and has computed a 28-year (1978-2006) daily field of Ekman transport and upwelling over the whole Arctic Basin.  Preliminary analyses indicate that the Ekman layer variability may have played a prominent role in observed changes of sea-ice cover and halocline layer variations.  The PI proposes to use this new dataset to study more comprehensively the impacts of upwelling and Ekman transport variability on the sea-ice and upper Arctic Ocean.  The results would demonstrate the important values of satellite data (several types of remote sensing data were used in computing Ekman pumping) in understanding the changes of the Arctic Ocean – a key criterion of NASA’s Cryospheric Science Program in supporting oceanography projects.  The results will greatly enhance the opportunity to get future projects funded by NASA, an agency that WHOI Arctic PIs have not fully exploited.  The PI also plans to archive the dataset, and make it accessible to all WHOI PIs.  This would be beneficial to those WHOI Arctic projects that use the upwelling data.