1. Eddies in the Beaufort Sea & its impact to ecosystem Watanabe (2011, JGR) & Nishino et al. (2011, GRL) 2) Preliminary results of XCTD measurement during UNCLOS 2011 cruise Kikuchi et al. (Abstract submitted to OSM 2012 in SLC in late Feb.) Figure 13(a), Watanabe (2011) Figure 1, Nishino et al. (2011)

2. Eddies in the Beaufort Sea & its impact to ecosystem Pacific Summer Water (PSW) One of the predominant sources of heat, fresh-water, and nutrients in the Arctic Ocean, especially for the Canada Basin (Beaufort Gyre). R/V Mirai R/V Mirai Arctic Cruise in 2010 (MR10-05) ?? Bering Strait Shelf slope of the Chukchi Sea Advection into the Canada Basin Advection into the Canada Basin as, Sub-surface anti-cyclonic cold-core eddies Sub-surface warm core eddies Surface-intensified warm-core eddies Topographic- controlled current Buoyancy-driven (coastal) current Bering Str. Canada Basin Chukchi Sea Eastern Siberian Sea Seminar at AWI November 11, 2011

3. Eddies in the Beaufort Sea & its impact to ecosystem Temperature at 50m depth observed in MR10-05 R/V Mirai Very large warm-core eddy was found during MR10-05 !! (Nishino et al., 2011GRL; http://www.jamstec.go.jp/e/about/press_release/20110826/) (Nishino et al., 2011GRL; http://www.jamstec.go.jp/e/about/press_release/20110826/) Seminar at AWI November 11, 2011

4. Temperature at 50m depth observed in MR10-05 Eddies in the Beaufort Sea & its impact to ecosystem Unusually large warm-core eddy Anti-cyclonic, ~100km in diameter, Anti-cyclonic, ~100km in diameter, Ammonium-rich shelf water Ammonium-rich shelf water Seminar at AWI November 11, 2011

5. Temperature at 50m depth observed in MR10-05 Eddies in the Beaufort Sea & its impact to ecosystem Unusually large warm-core eddy Anti-cyclonic, ~100km in diameter, Anti-cyclonic, ~100km in diameter, Ammonium-rich shelf water Ammonium-rich shelf water  30 % higher biomass of picophytoplankton Picophyto plancton (e.g.,flagellate) Large phytoplankton (e.g., diatom) Seminar at AWI November 11, 2011

6. Temperature at 50m depth observed in MR10-05 Eddies in the Beaufort Sea & its impact to ecosystem Picophyto plancton (e.g.,flagellate) Large phytoplankton (e.g., diatom) Unusually large warm-core eddy Anti-cyclonic, ~100km in diameter, Anti-cyclonic, ~100km in diameter, Ammonium-rich shelf water Ammonium-rich shelf water  30 % higher biomass of picophytoplankton Seminar at AWI November 11, 2011

7. Eddies in the Beaufort Sea & its impact to ecosystem How are such surface-intensified warm-core eddies generated in the western Arctic Ocean? in the western Arctic Ocean? (Watanabe, 2011JGR... Published on the exact same day (Aug.26 2011) as Nishino et al. (2011GRL).) Eddy-resolving coupled sea ice-ocean model with atmospheric forcing were used to examine meso-scale eddies and shelf-basin exchange of Pacific Summer Water. MODIS SST in September 2003 [Watanabe, 2011JGR] Temperature at 50m depth observed in MR10-05 Seminar at AWI November 11, 2011

8. Eddies in the Beaufort Sea & its impact to ecosystem How are such surface-intensified warm-core eddies generated in the western Arctic Ocean? in the western Arctic Ocean? (Watanabe, 2011JGR... Published on the exact same day (Aug.26 2011) as Nishino et al. (2011GRL).) Eddy-resolving coupled sea ice-ocean model with atmospheric forcing were used to examine meso-scale eddies and shelf-basin exchange of Pacific Summer Water. Pacific water content during May 1 - December 31 2003. [Courtesy from E. Watanabe] Seminar at AWI November 11, 2011

9. Eddies in the Beaufort Sea & its impact to ecosystem How are such surface-intensified warm-core eddies generated in the western Arctic Ocean? in the western Arctic Ocean? (Watanabe, 2011JGR... Published on the exact same day (Aug.26 2011) as Nishino et al. (2011GRL).) Eddy-resolving coupled sea ice-ocean model with atmospheric forcing were used to examine meso-scale eddies and shelf-basin exchange of Pacific Summer Water. Type I Type I is generated during Summer time in the vicinity of Barrow canyon by a combination of outflow of warm PSW with low potential vorticity and lateral shear of the canyon jet [Kubokawa (1991) theory]. Seminar at AWI November 11, 2011

10. Eddies in the Beaufort Sea & its impact to ecosystem How are such surface-intensified warm-core eddies generated in the western Arctic Ocean? in the western Arctic Ocean? (Watanabe, 2011JGR... Published on the exact same day (Aug.26 2011) as Nishino et al. (2011GRL).) Eddy-resolving coupled sea ice-ocean model with atmospheric forcing were used to examine meso-scale eddies and shelf-basin exchange of Pacific Summer Water. Type I Type I is generated during Summer time in the vicinity of Barrow canyon by a combination of outflow of warm PSW with low potential vorticity and lateral shear of the canyon jet [Kubokawa (1991) theory]. Type II & III Type II & III originate from an eastward current along the Beaufort shelf break. Type II is spawned from the shelf slope at mid-depth during early summer. Type III is generated from surface isopycnal front over the shelf break during late summer. Seminar at AWI November 11, 2011

11. Eddies in the Beaufort Sea & its impact to ecosystem How are such surface-intensified warm-core eddies generated in the western Arctic Ocean? in the western Arctic Ocean? (Watanabe, 2011JGR... Published on the exact same day (Aug.26 2011) as Nishino et al. (2011GRL).) Eddy-resolving coupled sea ice-ocean model with atmospheric forcing were used to examine meso-scale eddies and shelf-basin exchange of Pacific Summer Water. NCEP/NCAR SLP averaged from June to August. (b) 2003, (c) 2007 [Figure 4, Watanabe (2011)] under weak or westerly wind conditions during summer Meso-scale eddies are primarily generated and induce the shelf-to-basin transport under weak or westerly wind conditions during summer, while wind-driven Ekman offshore-transport is a major driver in the easterly wind regime. Year 2003(2007) is the former (latter) case. Seminar at AWI November 11, 2011

12. Eddies in the Beaufort Sea & its impact to ecosystem Temperature at 50m depth observed in MR10-05 Very large warm-core eddy was found during MR10-05 !! (Nishino et al., 2011GRL; http://www.jamstec.go.jp/e/about/press_release/20110826/) (Nishino et al., 2011GRL; http://www.jamstec.go.jp/e/about/press_release/20110826/) H HL Wind-condition around the Beaufort shelf-slope was calm in July 2010, which suggests that very large warm-core eddy observed during MR10-05 cruise was generated near the Barrow canyon in July 2010.... Seminar at AWI November 11, 2011

13. Eddies in the Beaufort Sea & its impact to ecosystem Seminar at AWI November 11, 2011 1) Eddies in the Beaufort Sea & its impact to ecosystem Watanabe (2011, JGR) & Nishino et al. (2011, GRL) Figure 13(a), Watanabe (2011) Figure 1, Nishino et al. (2011) Shelf slope and basin observation Eddies, upwelling (shelf basin exchange), acidification, impact to ecosystem and so on...