David M. Legler U.S. CLIVAR Office usclivar legler @ usclivar

1. CLIVAR A presentation for the NVODS Workshop September 11, 2003 David M. Legler U.S. CLIVAR Office www.usclivar.org legler@usclivar.org and member of US-DMAC committee as well as former chair of the WOCE Data Products Committee…

2. What is CLIVAR? (hint: it’s involves more than the ocean!) • Scope of activities • CLIVAR needs/requirements • CLIVAR and data management

3. CLIVARClimate Variability and Predictability • What causes the variability of the earth's climate on time scales from seasons to centuries and can we predict it? • Can we distinguish natural from anthropogenic induced variability? • Science Plan - 1995 • U.S. CLIVAR SSC formed - Summer 1998 • International CLIVAR Conference - December 1998 • CLIVAR will extend for at least another 10 years

4. Illustrative questions for CLIVAR • How can we better predict El Niño and its impact on climate? • What are its links to higher frequency (e.g., MJO) and to decadal variability? • Decadal variability has been shown to impact climate in many regions…can we ever predict this variability? • What are the some of the mechanisms than can lead to abrupt climate change? • How does El Niño change under a changing climate?

5. U.S. CLIVAR Objectives • Identify and understand the major patterns of climate variability on seasonal and longer time scales and evaluate their predictability; • Expand our capacity to predict short-term (seasonal to interannual) climate variability and search for ways to predict decadal variability; • Better document the record of rapid climate changes in the past,as well as the mechanisms for these events, and evaluate the potential for abrupt climate changes in the future; • Evaluate and enhance the reliability of models used to project climate change resulting from human activity, including anthropogenic changes in atmospheric composition; and • Detect and describe any global climate changes that may occur.

6. The CLIVAR Vision... An important legacy of CLIVAR will be an improved climate observing system,as well as a more comprehensive and useful climate record CLIVAR will contribute the fundamental underpinnings of critical physical processes that lead to reducing uncertainties in coupled climate models used for prediction • CLIVAR will help contribute to the development of robust dynamical frameworks for understanding climate changes

7. Approach • Improvements in the instrumental record and observing system • document past, ongoing, and future climate fluctuations • better elucidate their structures and mechanisms • provide initial conditions for model data assimilation and forecasting • Model application, experimentation, and improvement • develop long-term model data sets (e.g. retrospective analyses) to study climate variability • assess inadequacies and improve the capabilities of models to simulate and predict climate variability • explore mechanisms of climate variability • develop dynamical hypotheses to help focus observational requirements

8. Approach • Empirical studies of the climate record from instruments, satellites and proxy records, and climate model simulations • define patterns of climate variability • develop and test hypotheses • Regional and process field studies • quantify specific processes that must be included in successful climate models • Identify processes for which present treatment is inadequate.

9. CLIVAR Regional Implementation Working groups address global synthesis, modeling, and prediction

10. Atlantic Basin Issues • NAO/AO/AM • Mechanisms that govern its variability? • Low-frequency trends? • Ocean, land, sea-ice feedbacks? • Numerous applications • TAV • Influence of ENSO, NAO? • Role of coupling in TNA? Of subtropical cells? • Extent of land influences? • Climate predictability beyond tropics? • MOC • Variability of ocean heat transport? • Sensitivity to sfc forcing? • Role of thermohaline circulation in abrupt climate change?

11. http://www.clivar.org/organization/atlantic/IMPL/

12. East Pacific Investigation of Climate Processes in the Coupled Ocean-Atmosphere System (EPIC) • Enhanced Monitoring • 1999-2003 • Enhancements to the TAO array • IMET mooring at 20S • Radionsonde, flux msmts, etc. from twice-yearly TAO tender cruises 95W, 110W • IOP: Sep/Oct 2001 • 2 ships, 2 aircraft • Enhanced Regional Obs • Terrestrial and lower-atm obs

13. Other Observations & Products of Interest

14. Modeling Activities Some Objectives: • Improve predictions on seasonal-to-interannual time scales • Assess predictability of decadal variability • Evaluate and enhance the reliability of models used to project climate change U.S. teams of modelers, observationalists, and diagnosticians will address two major areas of uncertainties in climate change models • Ocean mixing and low-latitude cloud feedbacks • Development of robust dynamical synthesis frameworks (e.g. data assimilation) for understanding climate variability and predictability and to guide observation system design • Recent workshops on • Ocean data assimilation • Atmospheric data assimilation/reanalyses • Coupled data assimilation CLIVAR will generate and utilize many TB of model data/products…data management challenge

15. CLIVAR Needs… • The requirements for developing climate data are stringent as the signals we are trying to detect are often very small • CLIVAR needs access to a variety of obs, models, analyses, paleo-proxy data, archives, etc from multiple disciplines (e.g. ocean, atm, land) to address the coupled climate system • Access to browse products • Time-critical data/products are needed for climate forecasting (e.g. ENSO predictions) • Data/products of a known quality • Attributes that describe errors, uncertainties, and data quality must be an integral part of the data system • Versioning/tracking/tagging is critical (experiments must be repeatable)…observational data can be corrected many times.

16. CLIVAR and Data Management • WOCE heritage: CLIVAR has picked up some parts of the WOCE (ocean) data system…BUT CLIVAR is more than the oceans! • CLIVAR is the home for • Some observation system elements and their data systems • Field experiment observation data (UCAR-JOSS) • Numerous model and value-added products • Various regional/system-wide data/product activities • Many (not all) of these consider data management All of them need to be fully entrained in the development of a comprehensive climate data/product/info management system

17. Legacy of WOCE WOCE V3 DVD’s 2 DVDs, 12GB data 10+ yrs of in-situ & satellite ocean data and products netCDF-COARDS compliant files Consistent and documented QC Common metadata stds, conventions, etc. Search tool/file pointers

18. WOCE Data System CLIVAR Data Assembly Data Centers (DACs) play a central role in assembling, QC’ing, and distributing ocean data All DACs have OpenDAP servers, some with LAS, etc Knowledgeable and cooperative team

19. CLIVAR’s Role in Data Management • Helps to develop and assess requirements of the systems that will deliver climate data, products, and information; • Implements some (e.g. ocean) elements of the observing system and their respective data management systems, the frontline for new obs technology and data systems • Develops synthesis frameworks (e.g. data assimilation/reanalyses) that utilize (and assess) the climate observations, products, and information; • Contributes assembled data, products and their attributes; • Cooperates with other activities (DMAC, OTI, OOPC, etc) leading data system development; • Provides feedback on acceptable metadata and data “models”; • Help sustain current Data Assembly Centers (DACs), regional, and specialized data centers • CLIVAR Global Synthesis and Observations Panel (GSOP) is the CLIVAR group charged with addressing data management issues. First meeting is being planned (early 2004)

20. For Consideration • CLIVAR is an important customer/user of NVODS • CLIVAR can contribute data, metadata to global component of IOOS …help develop IOOS data system • CLIVAR can help extend NVODS technology to other disciplines • Importance of products (very different from observations) • Model/value-added products • Browse products • What metadata should be included? • Importance of a data/metadata model and standards • encourage contributions of a more comprehensive set of data/metadata • Sufficiently extensible to address stringent needs of climate

21. Further Information: www.clivar.org www.clivar2004.org

23. NVODS Activities…CLIVAR Input • Develop a Comprehensive IOOS Data Model • Deliver time-critical (real-time) data to data assembly and operational modeling sites • Characterize the need for real-time data. • Develop DMAC Middleware • Determine the breadth of data management solutions in use by IOOS data suppliers, which must be supported by IOOS middleware. • Determine the breadth of legacy and new client applications that should be supported. Similarly survey and prioritize requirements for delivery of formatted subsets to users. • Make data available using IOOS middleware solution • Work with suppliers of data to make data available through the DMAC middleware solution. • Data Manipulation Services • Prioritize Data Manipulation Services, including aggregation, re-gridding, and simple transforms such as averages and extrema. • Develop Metrics and Implement Performance Monitoring • Determine specifications for Metrics and Performance Monitoring. • Implement Middleware Security (Cross-discipline effort with all DMAC) • Provide guaranteed geo-temporal-referenced browse for all IOOS data