Co-Convenors: Kyung-Il Chang (Korea), William R. Crawford (Canada), Shin-ichi Ito (Japan) and Vyacheslav Lobanov (Russia)
Mesoscale eddies move through the ocean carrying physical, biological, and chemical anomalies. They translate over space scales of hundreds to thousands of kilometers and exist for periods lasting from months to years. Eddies are found throughout the North Pacific Ocean in association with strong boundary currents like the Kuroshio and Oyashio and the Alaskan Stream, and also with North Pacific eastern boundary currents like the California and Alaska Currents. They are also prevalent in marginal seas. Generation and evolution of eddies are thought to be related to the shear instability of boundary currents like the Kuroshio, and topographic features in the California and Alaska Currents. Mesoscale eddies affect the structure of marine plankton in various ways. Horizontal advection and vertical mixing by eddies contribute to the generation of high chlorophyll concentration off the coast. They draw shelf water containing nutrients and planktons into the deep offshore waters. Mesoscale eddies are also important for survival of larvae. Eddy pumping also plays a role in episodic nutrient injections into the photic zone resulting in enhanced primary production inside the eddy for cyclonic eddies. For anticyclonic eddies, ageostrophic upwelling and divergent Ekman pumping due to winds over the eddies yield upwelling within the eddy. This workshop will address: 1) dynamical characteristics of mesoscale eddies in different parts of PICES domain, focusing on their similarity and difference; 2) influences of eddies in constituting the dominant physical forcing on the ecosystems; and 3) expected future eddy activities and their possible impacts on North Pacific ecosystems.