American Geophysical Union Become an AGU Member
Subscribe to AGU Journals
AGU Home AGU Publications

Editor's Highlight

Read Full Article (file size: 2603568 bytes)    Cited by

GEOPHYSICAL RESEARCH LETTERS, VOL. 33, L08605, doi:10.1029/2005GL025624, 2006

Pacific Ocean inflow: Influence on catastrophic reduction of sea ice cover in the Arctic Ocean

Koji Shimada

Institute of Observational Research for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan


Takashi Kamoshida

Institute of Observational Research for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan


Motoyo Itoh

Institute of Observational Research for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan


Shigeto Nishino

Institute of Observational Research for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan


Eddy Carmack

Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney, British Columbia, Canada


Fiona McLaughlin

Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney, British Columbia, Canada


Sarah Zimmermann

Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney, British Columbia, Canada


Andrey Proshutinsky

Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA


Abstract

The spatial pattern of recent ice reduction in the Arctic Ocean is similar to the distribution of warm Pacific Summer Water (PSW) that interflows the upper portion of halocline in the southern Canada Basin. Increases in PSW temperature in the basin are also well-correlated with the onset of sea-ice reduction that began in the late 1990s. However, increases in PSW temperature in the basin do not correlate with the temperature of upstream source water in the northeastern Bering Sea, suggesting that there is another mechanism which controls these concurrent changes in ice cover and upper ocean temperature. We propose a feedback mechanism whereby the delayed sea-ice formation in early winter, which began in 1997/1998, reduced internal ice stresses and thus allowed a more efficient coupling of anticyclonic wind forcing to the upper ocean. This, in turn, increased the flux of warm PSW into the basin and caused the catastrophic changes.

Received 27 December 2005; accepted 13 March 2006; published 21 April 2006.

Index Terms: 4207 Oceanography: General: Arctic and Antarctic oceanography (9310, 9315); 4532 Oceanography: Physical: General circulation (1218, 1222); 4540 Oceanography: Physical: Ice mechanics and air/sea/ice exchange processes (0700, 0750, 0752, 0754).


Read Full Article (file size: 2603568 bytes)    Cited by

Citation: Shimada, K., T. Kamoshida, M. Itoh, S. Nishino, E. Carmack, F. McLaughlin, S. Zimmermann, and A. Proshutinsky (2006), Pacific Ocean inflow: Influence on catastrophic reduction of sea ice cover in the Arctic Ocean, Geophys. Res. Lett., 33, L08605, doi:10.1029/2005GL025624.