Journal of Oceanography, Vol. 66 (No. 3), pp. 319-328, 2010
Hiromichi Ueno1*, William R. Crawford2 and Hiroji Onishi3
1Japan Agency for Marine-Earth Science and Technology, Yokosuka, Kanagawa 237-0061, Japan
2Institute of Ocean Sciences, Fisheries and Oceans Canada, Sidney, B.C. V8L4B2, Canada
3Graduate School of Fisheries Science, Hokkaido University, Hakodate 041-8611, Japan
(Received 26 January 2009; in revised form 16 November 2009; accepted 3 December 2009)
Abstract: The impact of the Alaskan Stream (AS) eddies on the chlorophyll a (chl-a) distribution in the central subarctic North Pacific was investigated through analysis of chl-a and altimetry data from satellite observations. Altimetry observations provided the locations of mesoscale eddies in time and space within the maps of chlorophyll distributions. The climatological chl-a distributions averaged in the area and time showing presence of AS eddies suggested that AS eddies contributed significantly to the chl-a distribution in the deep-sea region of the subarctic North Pacific. The chl-a distribution was closely related to the AS eddies regardless of whether the eddy was located in or detached from the AS. A combination of two or three AS eddies sometimes formed high chl-a concentration belts that injected chlorophyll and coastal nutrient-rich waters southward from the Aleutian Islands far into the deep-sea region of the subarctic North Pacific. These results indicate that chl-a distribution in the central subarctic North Pacific was strongly impacted by AS eddies.