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CLIVAR Pacific panel
Main Issues
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ENSO (and related aspects)
Observational requirements
Metrics (societal and scientific)
SPCZ
Eastern Pacific biases (VOCALS)
Interbasin connections
SPICE
Interaction with other panels
ENSO
• Understanding and predicting ENSO:
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Background state => MJO  ENSO
Background state => annual cycle  ENSO
Background state  ENSO
ENSO and stochastic forcing
ENSO and greenhouse warming
Decadal timescales in ENSO
ENSO metrics (diagnostics and observations)
ENSO sensitivity to climate change:
Observational requirements
• Monitoring of SST, thermocline depth, boundary
and interior transports
• Monitoring of Walker circulation (see Vecchi and
Soden, Nature 2006)
• Monitoring of ENSO-MJO relationship
• Monitoring of subsurface anomalies (ARGO,
TAO, altimeter)
• Monitoring of heat flux convergences via drifter
data, ARGO data
ENSO-WWB interactions,
• WWB activity modulates and is modulated by
ENSO (Eisenman, Jin, Lengaigne)
• WWB is modulated by the annual cycle (Hendon
and Zhang)
• Nature and Dynamics of these interactions still
unclear
• Evidence for intensification of WWB and WWBENSO interactions (Jin et al. 2007)
• What background conditions make this
interaction favorable?
ENSO-WWB interactions,
WWB modulation by temperature
Eisenman et al. 2005
•East-ward propagating coupled instabilities
ENSO-WWB interactions: observational
requirements
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Monitoring of zonal temperature advection
Monitoring of MJO and warm pool heat budget
“Precise” knowledge of WWB initial conditions
Monitoring of MJO-warm pool front propagation
(satellites) and subsurface response (TAO,
altimetry)
Understanding the South Pacific Convergence
Zone
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Why is there a SPCZ?
How is it connected to the ITCZ?
How does the SPCZ interact with the MJO?
How does the SPCZ interact with the SST
How does the SPCZ respond to tropical and
extratropical SST forcing on interannual to
decadal timescales?
• What influence does the SPCZ wind
convergence and its modulation have on
southwest Pacific boundary currents?
Understanding the SPCZ
• Clouds and temperatures in observations (left)
and NCAR CCSM3 model
Understanding the SPCZ: observational
requirements
• Series of detailed process studies needed (a la
TOGA-COARE) focusing on cloud formation,
boundary layer dynamics, atmosphere-ocean
interactions
• Relationship between SST, SPCZ, Rain and
Salinity using satellite data (Aquarius,SMOS)
• Response of ocean to variations in SPCZ
(ARGO, drifter data)
• SPCZ and subduction and mode-water
formation (ARGO, Repeat hydrography)
Improving model biases in the eastern tropical
Pacific, cold bias and warm bias, SPCZ bias
• Possible origin of cold bias in coupled models
(missing ocean biology, under-representation of
TIWs, mixing, missing diurnal cycle of insolation,
under-representation of Galapagos effect,
uncertainties in convective parameterizations)
• Possible origin of warm bias in stratus regions
(problems with cloud parameterizations and
cloud-aerosol interactions, missing Tsuchiya jets,
lack of horizontal resolution, underrepresentation of eddies in AR4 CGCMs)
Improving model biases in the eastern tropical
Pacific, cold bias and warm bias
• Clouds and temperatures in observations (left)
and NCAR CCSM3 model
Improving model biases in the eastern tropical
Pacific, cold bias and warm and SPCZ bias:
observations needed
• Vertical chlorophyll profiles => bio-optical
feedbacks
• Better estimates of eddy-induced heat transports
in the southeastern Pacific (VOCALS)
• Better observations of Tsuchiya Jets and their
variability
• Observational estimates of TIW heat budgets
• Focused process study on SPCZ needed!
Southwest PacIfic Ocean Circulation and
Climate Experiment
Goal: Observe, Model,
and understand the
role of the SW Pac
Ocean in the:
-Large scale decadal
climate modulationENSO
-Tasman Sea area
-Generation of local
climate signatures
A. Ganachaud, W. Kessler, S. Wijffels, K. Ridgway, W. Cai,
N. Holbrook, M. Bowen, P. Sutton, B. Qiu, A. Timmermann, D.
Roemmich, J. Sprintall, S. Cravatte, L. Gourdeau, T. Aung
Thermocline water currents
SPICE Field Experiment
Overview
Outset for a large scale
field experiment
3-North Coral Sea
Pilot study
1-Monitoring
inflow
and bifurcation
2-EAC variability
monitoring
A-Existing large scale
programs
B-Pilot studies
C-Sustained observations
CTD section
SPICE cruise
XBT section
Mooring array
Glider section
Mooring line
SPICE
www.ird.nc/UR65/SPICE
•Implementation plan in progress
Based on existing infrastructures and
research groups
Need for a process study in the SPCZ
Workshop on Western Tropical Pacific: Hatchery
for ENSO and Global Teleconnections
Guangzhou CHINA, 26-28 November 2007
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To address key science questions, such as:
- does the South China Sea play an important role in the climate system or is it merely responding to
Pacific/Indian forcing?
- How important is the South China Sea Throughflow in draining heat out of the Pacific?
- What triggered the 2006/07 El Nino event?
- What were the global impacts of the 2006/2007 El Nino?
- How good was the forecast skill of the 2006/2007 El Nino?
- How does the longterm Indian ocean warming affect the global climate system (including ENSO)?
- What is the origin of the longterm Indian ocean warming?
-How does the warm pool respond to anthropogenic climate change (atmospheric versus oceanic feedbacks)?
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Further engage the Chinese oceanographic and climate research community in CLIVAR
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Link the Chinese observational activities to other international field programs (such as SPICE,
NPOCE and PACSWIN)
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Seek international coordination in terms of field experiment timing and infrastructure (sharing
ships, common XBT lines, ...), large scale modeling projects, ocean, atmosphere and coupled.
http://www.clivar.org/organization/pacific/meetings/pacific_workshop.php