1. CLIVAR Report to WOAP4
Detlef Stammer

2. CLIVAR (Climate Variability and Predictability)
Mission
To observe, simulate and predict changes in the earth’s climate system with a focus on ocean-atmosphere interactions, enabling better understanding of climate variability, predictability and change, to the benefit of society and the environment in which we live.
See p. 2 of Draft IP 2

4. New: Clivar/CliC Arctic Panel

5. Planning is moving forward with no sun-set date in effect any more.
Focus of next 2 years
Planning is moving forward with no sun-set date in effect any more.

6. Each panel/WG was asked to identify:
Building consensus until 2013 and beyond
Each panel/WG was asked to identify:
Imperatives over the coming years to 2013 and, perhaps, continuing over the next decade? Activities that "must" be continued and/or implemented because they are of the highest scientific importance with a high likelihood of success.
What are the frontiers for the next decade and beyond?
What key developments to enabling infrastructure necessary to deliver to the above.
Organized around
WCRP crosscutting topics (ACC, AC&C, decadal and seasonal prediction, sea level rise, monsoon and extremes) under COPES
Additional focus on ocean observations, synthesis and modeling as particular CLIVAR contributions to overarching COPES themes.
Outcomes factored into WCRP Implementation Plan

7. CLIVAR Imperatives Anthropogenic Climate Change Long term change
Natural versus forced variability
Regional phenomena and impacts
Extremes
Decadal Variability, Predictability and Prediction
Determination of predictability
Mechanisms of variability
Role of oceans
Adequacy of observing system
Initialization
Monsoons
Extremes - drought
Intraseasonal and Seasonal Predictability and Prediction
Role of land/ocean (GOALS)
Initialization
Monsoons, ISV/MJO

8. CLIVAR Imperatives Anthropogenic Climate Change
Decadal Variability, Predictability and Prediction
Intraseasonal and Seasonal Predictability and Prediction
Improved Atmosphere and Ocean Components of ESMs
Ocean model development
Analysis and Evaluation
Process studies/“Climate Process Teams”
Data Synthesis and Analysis
Ocean
Coupled Data Assimilation Systems (with WOAP)
Ocean Observing System
Development and System Design
(Build LINKS WITH IGBP for Carbon, Biogeochemistry, Ecosystems)
Capacity Building

9. GSOP Efforts Chairs: B. Sloyan, K. Haines (WOAP member), D. Stammer
Implementation of OO’09 Outcome (jointly with OOPC)
Reanalaysis of global historic hydrography
Reanalysis of XBT data
Analyze global budgets and sea level
EazyInit: Providing initial conditions for seasonal- to decadal predictions.
Improving initial conditions and initializations.
Preparing for Coupled Data assimilation
GSOP Efforts

10. Decadal variability and predictability
Some key questions
To what extent is decadal variability in the oceans
and atmosphere predictable?
What are the mechanisms of variability?
Does the oceanic variability have atmospheric relevance?
Do we have the proper tools to realize the predictability?
Need for (coupled) data assimilation systems to initialize models
Are models “good enough” to make skillful predictions?
Adequacy of climate observing system?
Global number of temperature
observations per month as a
function of depth

11. Decadal variability & predictability
First attempts already underway
Decadal prediction part of CMIP5 protocol – Joint design by WCRP/WGCM/WGSIP/CLIVAR sub group
Opportunities for diagnostic sub-projects
CLIVAR Workshops
AIP/GSOP Earth System Initialization for Decadal Predictions Workshop (4 – 6 Nov 2009) – KNMI, Utrecht, The Netherlands
Upcoming: WGOMD/GSOP Workshop on Decadal Variability, Predictability and Predictions: Understanding the Role of the Ocean Sep 2010, NCAR, Colorado, USA
Atlantic Panel coordination of activities to monitor the Atlantic MOC
Ocean observations will be at the heart of decadal climate prediction systems. Major challenges will, therefore, be to continually assess whether existing and planned ocean observing systems are optimal for decadal predictions and to address any identified deficiencies. As one example, a tremendous advance has been the measurements of temperature and salinity over the upper 2000 m of the global ocean currently provided by ARGO profiling floats. There exists, however, a need to assess whether observations from below 2000 m would be of use in decadal climate predictions by more completely characterizing deep ocean conditions, such as the lower limb of the MOC, and in assessing other changes such as in abyssal ocean heat content. Also, with a lifetime of individual ARGO floats of only a few years, there is a need to evaluate and minimize the impact of instrumentation changes on the quality of the records both for climate analyses and for initializing prediction models.

12. MOC – issues and challenges
Our present understanding and observations of the deep ocean and MOC are inadequate to carry out a rigorous process of setting priorities and evaluating trade-offs. No systematic observing system design studies have yet been carried out for the global MOC and deep inventory.
Nonetheless, substantial progress has been made in recent years (there are currently 25 individual contributions measuring components of the Atlantic MOC). Two areas are still hanging fruits and need further progress: the Arctic (CliC is mainly cryosphere) and the Atlantic Warm pool (with ties to VAMOS).
A challenge for the community is to make the transition from a collection of observing elements to an integrated, coherent observing system.