Proposal to CLIVAR Shoshiro Minobe (Hokkaido University, Japan) Emanuele Di Lorenzo (Georgia Institute of Technology, USA) Mike Foreman (Institute of Ocean Science, Canada) Toshio Suga (Tohoku University, Japan) Hiroaki Saito (Tohoku National Fishery Research Institute, Japan, former IMBER SSC member) Hiroshi Ogawa (Tokyo University, Japan, IMBER SSC member) Co-chairs of PICES WG “North Pacific Climate Variability and Change” Hiroshi will attend IMBER SSC/CLIVAR SSG meeting in Mexico, June

Under WCRP & IGBP structure, CLIV(M)AR takes care of physical ocean physical conditions ocean

Two directions of importance of physical ocean physical conditions ocean Atmosphere Air-sea interaction Marine ecosystems Biogeochemical cycles Processes & regions are different!

CLIVAR endorsed projects West African Monsoon La Plata Basin Arctic/Subarctic Ocean Fluxes Tropical Atlantic Climate Experiment Southwest Pacific Ocean and Climate Circulation Experiment CINDY2011/ DYNAMO C20C (AGCM) Intra- Americas Study of Climate Processes Almost for the tropics

Example of topic: Ocean deoxyganation Keeling et al. (2010): “Ocean Deoxygenation in a Warming World” by two mechanisms Smaller solubility ◦ Warmer temperature leads to smaller solubility of O2 to the ocean,. Weakened ventilation ◦ Warmer temperatures prevent forming dense waters, resulting in weaker ventilations of thermoclines water. Old waters have smaller dissolved oxygen. Watanabe et al. 2003

Impact of PDO relating thermocline displacement on O2 Deutsch et al. (2011 Science) m observed dissolved oxygen off California PDO (or more accurately winds associated with it) changes the volume of suboxic water via thermocline variations. 400 m oxygen [  mol kg-1] WOA05 Oxygen minimum zone

Example of topic: Ocean acidification IPCC-AR4 As a direct consequence of ocean’s absorption of CO2, pH (-log 10 (H + )) of ocean reduces. pH has decreased by 0.1 (30% increase of H+ ion) from pre-industrial era, and is decreasing at 0.02/decade. Accompanied reduction of saturation level of carbonate calcium, i.e., aragonite used by coral etc. and calcite.

Acidification impacts Doney et al Ann. Rev. Mar. Sci.

Upwelling of corrosive acidified water Feely et al Science Physical processes, such as upwelling, water mass formation, advections are important in ocean acidification especially at depth.

Example of topic: Ocean Oligotrophication nutrient Current condition Future heated world warm & light cold & heavy warmer & lighter cold & heavy Vertical mixing weakened Vertical mixing Near surface reduction Implications: Reduced primary production Weakened CO2 absorption Impacts on marine ecosystems up down How vertical mixing occurs are not well known.

Meso & submeso-scale impacts on primary production Resplandy et al GBC Wide Swath Altimetry: SWOT Benitez-Nelson et al. (2007 Science) perpendicular velocity Total Chlorophyll a 1% light level We do not know much about how meso- and submeso-scales contribute to nutrient supply. Meso-scale eddy off Hawaii Island.

Two directions of importance of physical ocean physical conditions ocean Atmosphere Air-sea interaction Marine ecosystems Biogeochemical cycles Processes & regions are different! Need to widen the scope of CLIMAR CLIVAR CLIMAR Otherwise CLIVAR may loose the leadership of physical oceanography studies. IMBER

Important oceanic physical processes For the on-going changes of green ocean, a number of physical processes are important: ◦ ocean vertical and horizontal mixing associated with the mixed layer; horizontal and vertical advection due to sub-mesoscale and meso- scale phenomena; the transports of jets, striations and currents; water mass formation and ventilation; and air-sea interaction over SST fronts and eddies

Recommendation/proposal Therefore, we strongly recommend that in their future endeavors CLIVAR, or CLIMAR, assign appropriate weights to the understanding of physical processes that influence the biogeochemical cycles and marine ecosystems. For example, “variability and change of physical processes of the global oceans impacting on biogeochemical cycles and marine ecosystems” could be one of main themes for these programs, and could be studied by using field observations, data analysis and numerical modelings.

FUTURE collaborations For the aforementioned theme (not air-sea interaction), PICES especially its WG29 (regional climate model) and WG27 can contribute. PICES Working Group 27: North Pacific Climate Variability and Change Chair, CLIVAR PP member Japan: Shoshiro Minobe, Shin-ichi Ito, Takashi Mochizuki, Bunmei Taguchi USA: Emanuele Di Lorenzo, Enrique N. Curchitser, Steven J. Bograd, Takamitsu Ito Canada: Michael G. Foreman, Patrick F. Cummins, Korea: Soon-Il An, Sangwook Yeh, Chan Joo Jang China: Lixin Wu, Xiaopei Lin, Guimei Liu Russia: Tatyana Pavlova, Elena I. Ustinova, Yury I. Zuenko

If you are happy with this direction. After proper revising, we can send a proposal to CLIVAR SSG in time for the CLIVAR SSG/IMBER SSC meeting.

Oxygen reduction in Cal-COFI region from (Bograd et al. 2008)

Large uncertainty in future Keeling et al. (2010) “Ocean Deoxygenation in a Warming World” The results are three times different even for the same scenario!

Stramma et al Science Oxygen Minimum Zones Expands

Enhanced stratification leads to smaller primary production? Behrenfeld et al (2006 Nature)

Physical environments Physical processes, such as upwelling, water mass formation, advections are important for ocean acidification at depth. Feely et al Science

Large uncertainty for future Keeling et al. (2010) “Ocean Deoxygenation in a Warming World” Three times different for the same senario.