Transcript WCRP polar climate predictability initiative Vladimir Ryabinin www.wcrp-climate.org • Bergen workshop (October 2010): science-driven – Informal WCRP Report A notable gap was that between scientific communities,

WCRP polar climate
predictability initiative
Vladimir Ryabinin
www.wcrp-climate.org
• Bergen workshop (October 2010): science-driven
– Informal WCRP Report
A notable gap was that between scientific
communities, as most people knew only
a small minority of the other
participants.
…it seems apparent that progress in polar
predictability will require crossing
disciplinary boundaries to understand
the feedbacks between the troposphere
and the stratosphere, ocean, land, and
sea ice
(SST)
(Douville, 2009)
Predictability: seasonal
Seasonal Forecast from AER
(Atmospheric & Environmental Research)
(J. Cohen, 2011)
Role of snow cover
Snow Forced Signal
J. Cohen, 20…
Multiple feedbacks involving sea ice
J. Overland
-- > “Warm AO – cold continents”
J. Overland
A. Hall
A. Hall
Role of Sea Ice
Y. Orsolini
Predictability: inter-annual
Correlation between wintertime
Arctic sea ice area and SATs
Annual mean Arctic sea ice area anomalies and oceanic
volume flux (upper 125 m) through SpitzbergenNorway meridional (about 20E) cross-section
r = - 0.77
Cyclonic circulation
(Bengtsson, 2004)
Westerly winds
Barents Sea
Barents inflow
Predictability: decadal
(Boer & Lambert)
(Ed Hawkins)
Decadal: forced change + natural variability
J. Boer
Climate Predictions and Projections
Coupled Model Intercomparison
Experiment 5 – CMIP5
IPCC AR5
Climate-system Historical
Forecast Project - CHFP
sea ice,
stratosphere
Coordinated Regional Downscaling
Experiment – CORDEX
IPCC AR5
Arctic
Africa
Chemistry-Climate Model
Validation
Antarctic
• The nature of feedbacks appears to be different in the two
hemispheres leading to different “big questions”:
– Understanding and predicting the rate of Arctic sea ice loss
– Understanding the drivers of change in the Antarctic,
including connections to ozone, ocean circulation, carbon
uptake, and ice shelves
• Imperatives
– Improve models
– Identify measurement needs, both for initialization and for
monitoring variability and long-term changes
• IASC Atmosphere meeting in Denver (October 23, 2011)
– IASC-A sees itself as more “bottom up”, e.g. field
experiments, and sees the WCRP initiative as being very
complementary (link through Jim Overland, NOAA PMEL)
• Toronto workshop (April 2-4, 2012)
– Aim for around 30-35 people, representing science topics
and partner activities (some continuity with Bergen)
– Outcome will be a draft implementation plan to be
considered at the JSC meeting in July 2012
• Expected implementation mechanisms
– Targeted workshops
– Climate process teams
– Coordinated evaluation/assessment of data sets
• Observational data sets
• Reanalyses
• Seasonal predictions (CHFP)
• Historical simulations (CMIP)
• Decadal and longer timescale predictions (CMIP)
– OSSEs to define measurement needs
– Coordinated model experiments
WCRP Grand Challenges
• Provision of skillful future climate information on regional
scales (includes decadal and polar predictability)
• Regional Sea-Level Rise
• Cryosphere response to climate change (including ice sheets,
water resources, permafrost and carbon)
• Improved understanding of the interactions of clouds,
aerosols, precipitation, and radiation and their contributions
to climate sensitivity
• Past and future changes in water availability (with
connections to water security and hydrological cycle)
• Science underpinning the prediction and attribution of
extreme events
WCRP polar climate predictability initiative &
WWRP Polar Prediction Research Project: commons
• Models, a lot of similarities
• Observations, almost enough for NWP, not the case for climate
• Data assimilation:
melt ponds, land surface, stratosphere, more for climate
• Goal: seamless multi-scale prediction system
• Different readiness to address prediction needs in NH and SH
• Polar regions are only the focus of targeted improvements within
our projects but the overall progress in prediction will be achieved
by global systems -> need a reliable and welcoming entry of our
results into global systems – roles of WWRP & WCRP
• Same communities? How big is the overlap?
• Welcome to Toronto…