Jay McCrearyShang-Ping Xie

Niklas SchneiderNikolai Maximenko

Zuojun YuRyo Furue

Justin Small

THEME 1Indo-Pacific Ocean Climate

Jan HafnerYan Du

Oleg MelnichenkoIngo Richter

Takeaki SampeHyodae Seo

Hiroki Tokinaga

Ocean Circulation

Air-Sea Interaction

Climate

THEME 1Indo-Pacific Ocean Climate

Funding by Institutional Grants from JAMSTEC, NASA, NOAA

Individual Grants from NSF, NASA, NOAA, DOE

Ocean Circulationmapping of absolute ocean topography and subsurface currents

zonal jet like ocean featuresSouth China Sea Throughflow

subsurface jetsKuroshio

Air-Sea Interactionocean imprint on atmospheric boundary layer

deep influences of the Gulf stream on the atmospheremapping of high wind frequency of the world’s ocean

Climateeastern equatorial Pacific coupled processes

regional climate of HawaiiPacific decadal variability

El Nino/Southern Oscillationtropical Atlantic variability

THEME 1Indo-Pacific Ocean Climate

1992-2002 mean dynamic ocean topography: global map at mesoscale resolution

Data released to public in 2005http://apdrc.soest.hawaii.edu/projects/DOT/

Surface drifters Satellite altimetry NCEP wind GRACE gravity models

Zlotnicki et al.

Maximenko, Niiler, Melnichenko et al.

Up to 10 stationaryACC meanders;ACC interaction withbottom topography

Kuroshio Extention frontal system

North Atlantic circulation

Corrected South Atlantic system

New discovery of systems of stationary jets

Shown is mean zonal geostrophic velocity

Analysis of high resolution, multi-decadal OFES hindcast:

Dynamics of Kuroshio Path VariationN. Schneider, B. Qiu, H. Sasaki

Phas

e/T

ime

Kb erodes thermostad, warms SST?

In an OGCM, a commonly used value for the background diapycnal diffusivity (Kb) weakens the Tsuchiya Jets, erodes the thermostad, and warms the SST through the warming of the subthermocline water that upwells in the eastern Pacific.

Kb = 0 Kb = 0.1 cm2/s

T & u at x = 50o

w (shading) & T (contours) at eastern boundary

Kb

= 0

.1 c

m2 /

sK

b =

0

Furue, McCreary, Yu & Wang

Frequency of QuikSCAT high

winds (>20 m/s; color = % of time) and SST (°C; contours)　 during winter months (DJF).

Mapping High Sea Winds from Space T. Sampe and S.-P. Xie (IPRC)

High sea winds often blow at midlatitudes during wintertime, when low-pressure systems pass over. These low-pressure systems, however, usually have a scale of ~1000 km, while the high sea winds have much smaller scales. An analysis of satellite-measured sea-wind data indicates that underlying SST fields and topography significantly impact wind events over the ocean. High winds (stronger than 20m/s) are seen more frequently over the warmer flanks of oceanic fronts than over the colder flanks. The figure, for instance, shows that high winds occur very frequently over the Gulf Stream off the Canada coast, where there is a sharp SST gradient on the northern side of the Gulf Stream. SST influence on the intensity of momentum mixing within the near-surface atmosphere is the plausible mechanism of this remarkable correspondence between higher winds over the warmer waters. The figure also shows the orographic impact on wind speed over water. Frequent high winds are seen where air flows along high orographic features on the Greenland coast and coast of southern France (the “mistral”).

Precipitation (mm/day)

Deep Climatic Influences of the Gulf StreamS Minobe (Hokkaido U), A Yoshida, N Komori (JAMSTEC), S-P Xie, and RJ Small (IPRC)

Nature, accepted

The Gulf Stream's influence penetrates as high as 10 km into the upper troposphere, raising the possibility that the warm current forces planetary waves affecting climate in remote regions.

Satellite-Model Synergy

OFES captures Kuroshio Extension’s decadal oscillationB Taguchi1,2, S-P Xie1, N Schneider1, M Nonaka2, H Sasaki2, Y Sasai2

1. IPRC/UH Met; 2. JAMSTEC (FRCGC & ESC)

Satellite Altimeter (T/P)OFES

Ocean GCM for Earth Simulator(0.1o x 0.1o, 54 levels)

The advent of satellite altimetry and the Earth

Simulator made it possible to study variability of narrow jets

like KE for the first time

1993 2004

High-Resolution Modeling

North Pacific Coupled Processes and Decadal

VariabilityH. Seo, H. Tokinaga, N. Schneider, S.-P. Xie • Downscaling using an eddy-resolving

regional coupled model (SCOAR)

• Impact of coupled feedback on variability of KE and its downstream?

• Atmospheric and ocean soundings in the Kuroshio extension

• Kuroshio Implementation Panel

25km ROMS + 110 km RSM

July mean SST

July mean SSH

Cruises: 4 winter & 2 summer

Pacific Decadal Variability: The North Pacific Gyre OscillationE. Di Lorenzo, N. Schneider, A. J. Miller, K. Cobb, P. Franks et al.

Ocean circulationStudies of ocean circulation using the new observations and high-

resolution models• horizontal (surface, thermocline and sub-thermocline) and meridional overturning circulations

• the interactions• dynamics of surface and subsurface jets of the general circulation

Air-sea interactionDiagnose fluxes and processes that couple the ocean and atmosphere in

both the tropics and extratropics•response of the extratropical storm track to ocean heat transport convergence and SST

•interaction between the atmospheric and oceanic boundary layers•diagnoses and impact of air-sea heat fluxes in the Kuroshio and the Kuroshio Extension

Climate modes and predictabilityInvestigate coupled phenomena that determine the spatial patterns of the

climate and its variability• dynamics and predictability of climate modes ENSO, PDV, NAO, AO, IOD

• impact of climate change

PAU