GFI/BCCR Seminar: The Arctic Ocean volume, heat and fresh water transports during 2004-2010
Takamasa Tsubouchi (Alfred Wegener Institute for Polar and Marine Research)
The Arctic Ocean volume, heat and fresh water transports during 2004-2010
This study aims to reveal, for the first time, an inter-annual variability of heat and fresh water (FW) fluxes through the Arctic gateways (Davis, Fram Straits and Barents Sea Opening). We analyze around 1,000 moored instruments across the pan-Arctic boundary during October 2004 to May 2010, with supplement of 37 repeat CTD sections in BSO and PIOMAS output. Volume and salt conserved velocity fields are obtained applying box inverse model for consecutive 68 months. The result shows that obtained volume transports are reasonable both in averaged value and it’s seasonal variability in each four Arctic gateway. We quantify total boundary heat flux, as a sum of oceanic and sea ice contributions, is 180±57 TW (mean ± standard deviation for the 68 months). That of FW flux is 156±91 mSv. We find that annual mean boundary heat flux and FW flux (average from October to following September) changes from year to year. The highest boundary heat flux appears during 2004-2005, and lowest boundary heat flux appears during 2008-2009. In a same manner, the highest boundary FW flux appears during 2005-2006, and lowest boundary heat flux appears during 2008-2009. These heat and FW boundary fluxes are balanced with surface fluxes and storage terms. We discuss theses relations quantitatively.