Transcript ppt - WMO
Observations and their Analysis for WCRP/COPES Kevin Trenberth Chair WCRP Observation and Assimilation Panel WCRP: WMO/IOC/ICSU 1 World Climate Research Programme WOAP WOAP is primarily sponsored by WCRP but now also co-sponsored by GCOS, WOAP is a coordination Panel in WCRP Preferred channel for interactions GCOS and WCRP AOPC, OOPC and TOPC are also co-sponsored by WCRP WOAP helps to coordinate GCOS panels and issues WOAP serves to help with GEOSS workplans. Achievements, actions, issues Much material and background docs on WOAP website 2 World Climate Research Programme WOAP meetings I: 1-3 June 2005 New York II: 28-30 August 2006, Ispra, Italy III: 29 Sep-1 Oct 2008, Boulder, CO 3 World Climate Research Programme WOAP-III: MAJOR CONCERNS and ISSUES Climate data records Continuity and homogeneity of observations, especially from space Need for reprocessing of records But not in a piecemeal fashion Agreement on algorithms: coordination among groups Includes evaluation and assessment or results Need for reanalysis to produce global gridded fields Proliferation of reanalyses without ability to vet them All directed at producing best series of analyses given observations None directed at addressing effects of changing observing system on the record Archival and data management of records in ways to facilitate reanalysis and access 4 World Climate Research Programme WOAP Interactions with CEOS: 3 letters have been prepared by WOAP to CEOS. The first went from WCRP under Chair JSC (Church) signature. The 2nd and 3rd went jointly under Chair JSC and Chair SC GCOS (Church and Zillman). The latest went out January 2008 (request from GCOS-SC). These emphasize WCRP strategic views on the importance of taking observations of climate quality, and generating climate data records through better homogeneity and reprocessing. They encourage CEOS to implement their plan of action. 5 World Climate Research Programme WOAP Interactions with CEOS: They express the need for higher priority for climate. Issues: Continuity, continuity, continuity; The need for reprocessing and reanalysis of past data and coordination of these activities among agencies and variables; The need for multiple ECVs, for land, ocean, atmosphere domains; Importance of calibration, accuracy, benchmarks, and in situ observations; Concerns over risk to continuity with NPOESS cuts in de-scoping 6 World Climate Research Programme WOAP Interactions with CEOS: CEOS is responding to the GIP Highlights importance of update But coordination is weak. Reprocessing is occurring but with different groups using different standards and algorithms. Does not recognize ongoing WCRP efforts or expertise Does not adequately include a vetting and an assessment. Workshop planned for Nov 2009 without adequate consulting of groups engaged in CDRs 7 World Climate Research Programme WOAP Interactions with CEOS: How can GCOS apply pressure on CEOS and the space agencies to improve climate records through international coordination of reprocessing and the vetting of the products? 8 World Climate Research Programme WOAP Reanalyses • US workshop (NASA) on data for reanalyses: Sept 05 • ECMWF workshop atmospheric reanalyses: June 06 • ECMWF workshop on ocean data assimilation: Aug 06 • JMA, Third Intl Reanalysis Conference: Jan 08 (260 participants, 61 oral, 73 poster presentations) Reports on Reanalysis issues for Eos 1) Simmons, Trenberth and Uppala 2007 -action from WOAP-II 2) Report on the Japan conference and reanalysis issues published in Eos: Problems and Prospects for Reanalysis (Trenberth, Koike, and Onogi, 2008) Based on: Statement on Reanalysis from the 3rd WCRP Intl Meeting. 9 World Climate Research Programme WOAP Reanalyses Letter formally sent to lead countries and agencies involved in reanalysis seeking their support for further activities in reanalysis and pointing out the prospects; conference statement attached. Cc’d to program managers. WG set up jointly by WCRP and GCOS (WOAP and AOPC): on “development of improved observational data sets for reanalyses”. Chair Russ Vose. 10 World Climate Research Programme AR4 IPCC assessment: Chapter 3 is an indictment of many difficulties with continuity of the climate record, and a testament to the heroic struggles of those who nonetheless make sense out of the data. We can surely do better. Chief outstanding issue in reanalysis: The underlying data base is not constant, and changes disrupt the climate record. No baseline reference network to anchor the data Radiosondes improve and change type over time Satellites mainly after 1979, last order 5 years, drift in orbit, change instruments, calibration Bias corrections are applied but remain imperfect Continuity is a key issue, especially for climate change Further technological development, change and improvement is expected. Major challenge is to deal with changing observations11 World Climate Research Programme Some Goals 1. Improve and develop input data for climate analyses For monitoring low frequency variability, we need longterm stable homogeneous climate data records (of known quality) New WOAP/AOPC working group to help do this; Chair Russ Vose 2. Improve global estimates of interannual to decadal variability and their uncertainty. Improve the consistency of the record in the face of major changes to the observing system. One or more reanalysis must be targeted at the goal of producing the most consistent time series (rather than the best analysis at any time). 12 World Climate Research Programme Some other issues: Coordination of reanalyses: proliferation Are lessons learned from previous one? Is data set development systematic? Is there an adequate user base to examine results? Are resources (computer, people) being used wisely? Risk of lack of support if not done “right”? Problem arises from insufficient sustained funding: inhibits coordination, although good collaboration at scientist level. 13 World Climate Research Programme WOAP WCRP, IGBP, GCOS workshop on learning from IPCC First recommended by WOAP in August 2006; contacted IPCC (Susan Solomon) on how to take advantage of the lessons learned from AR4. A. H-S followed up. Resulted in a joint WCRP, IGBP, GCOS workshop on lessons learned from IPCC. An article published in the January 2008 WMO Bulletin gives the main issues facing WOAP and WCRP with regard to observations and issues related to COPES. WOAP should help facilitate the WCRP response to a number of recommendations from the Sydney workshop in formulating ways forward to the next IPCC assessment. Report completed BAMS article accepted 14 World Climate Research Programme IPCC recommendations Workshop, Sydney, 4-6 October 2007 Future Climate Change Research and Observations: GCOS, WCRP and IGBP Learning from the IPCC AR4 GCOS-117; WCRP-127; IGBP Report No. 58 (WMO/TD No. 1418) Jan 2008 Trenberth, K. E., 2008: Observational needs for climate prediction and adaptation. WMO Bulletin, 57 (1) 17-21. Global warming is “unequivocal”: Adaptation to climate change • • • • Assess vulnerability Devise coping strategies Determine impacts of possible changes Plan for future changes Requires information Imperative: A climate information system Observations: forcings, atmosphere, ocean, land Analysis: comprehensive, integrated, products Assimilation: model based, initialization Attribution: understanding, causes Assessment: global, regions, impacts, planning Predictions: multiple time scales Decision Making: impacts, adaptation An Integrated Earth System Information System Climate Information System WCRP Trenberth, 2008 WMO Bull Nature 6 December 2007 Future needs: Observations and Analysis Observations: in situ and from space (that satisfy the climate observing principles); A performance tracking system; Climate Data Records (CDRs) The ingest, archival, stewardship of data, data management; Access to data Data processing and analysis The analysis and reanalysis of the observations and derivation of products, Data assimilation and model initialization Climate Information System: WOAP role • Observations: advocating improved observations and analysis suitable for climate (satisfying the climate principles that are designed to ensure continuity of record). This especially includes those from space. • Data set development: evaluating observations and promoting their reprocessing and reanalysis into global fields. Developing new products and datasets. • Model datasets: promoting numerical experimentation • Making data available through the internet. • Diagnostics: developing analytical and diagnostic techniques to process observations and model data, and facilitate their comparison and evaluation. New products. Climate Information System: WOAP role: continued • Attribution: develop capabilities that contribute to attribution capability via studies and numerical experimentation to allow reliable statements to be made not only about what the state of the climate is, but also why it is the way it is and the mechanisms involved. • Predictability and prediction: PDO, NAO, AMOC; improve initialization of models, improve observations for this purpose; regional models (downscaling). • High impact events and extremes: exploring drought, flooding, precipitation intensity and frequency, hurricanes, storms • Model evaluations: model vs observations; water and energy cycles, forcings