Summary of S5: Mechanisms of change: Processes behind climate

variability in the North Pacific

Co-convenors: Emanuele Di Lorenzo (USA)Michael Foreman (Canada)Shoshiro Minobe (Japan)

Plenary Speaker: Mat Collins (University of Exeter, UK) Invited Speakers: Taka Ito (Georgia Institute of Technology ,

USA)Nathan J. Mantua (Southwest Fisheries Science Center, NOAA-Fisheries, USA)

10 oral, 2 poster presentations

Co-chairs WG27, North Pacific Climate Variability and Change

Plenary: Matt Collins (lead author of WG1, IPCC-AR5)

• One thing Matt did not mentioned is that the current trajectory of CO2 emission in the last 10-years is slightly higher than RCP8.5, high-end scenario in AR5. Thus, in AR6, a larger emission scenario will be presented. This automatically escalate all IPCC estimations, i.e., century end warming, sea-level rise, and sea-ice reductions.

Peters et al. (2013, Nature Climate Change)

Plenary: Matt Collins (lead author of WG1, IPCC-AR5)

• Hiatus (temporal stop or break global warming) is a big issue, and hiatus can be related to PDO.

Kosaka and Xie 2013 Nature

Nate Mantua (invited)East Pacific (east of the dateline) analysis since 1990.

Natural SLP (cyclonic circulation) trend

Natural warming trend

Atmospheric Teleconnections (atmospheric bridge) to PICES region

From North Atlantic(Krovnin)

From the tropical Pacific (Newman). ENSO forcing is an important component of PDO. Ocean heat persistency acts as a low-pass filter.

Rossby waves propagating westward

Rossby waves forced in the central North Pacific Propagate to the western North Pacific, where they Influence

- subpolar front SST (Newman)- Kuroshio extension: meridional migration, stable/unstable, etc. (Qiu)- nutrient (Minobe)- productivity in climate model (Chikamoto, poster)

Kuroshio Extension: Heat flux max.

Subpolar front (Oyashio front): SST grad. max.

Influence to the atmospheric circulation: over the Gulf of Alaskaover the eastern N-Pacific, leading to weak periodic behavior and longer predictability

Advection

Spiciness (density neutral temp/salinity anomalies) roughly along the subpolar front (Schneider)

Oxygen (inferred from salinity) from the interior ocean to the CalCOFI region by 8-10 years. (Di Lorenzo)

Anthropogenic aerosols

Iron inputs increased productivity increased respiration oxygen reduction (Taka Ito, invited)

Fish migration (Shin-ichi Ito)

Photos are taken from wikipedia

Northward feeding migration

Southward spawningmigration

Westward migration is important to adjust model to observed fish stocks 2002-2009. Fish observes SST or clouds?

2D version of NEMURO.fish for Pacific Saury

In-depth regional analyses

Loop current formation (Guo poster)

CalCOFI data relations to multiple climate indices (Kim)

California Current Ecosystem (CCE) Long-Term Ecological Research (LTER) program since 2004 (Miller)

Temperature and fish changes in Ulleung basin (Jung)

Conclusions of S5

• Processes that span long distances such as atmospheric teleconnection (simultaneous), ocean Rossby waves (4-5 years), advections (several to 10-20 years), and fish migrations (seasonal) are important in this anthropogenically and naturally changing world.