1 / 36

WORLDWIDE INTEGRATED STUDY OF EXTREMES (WISE)

“Extremes constitute the major stress factor on a number of environmental and socio-economic systems.” (Heino et al., 1999). WORLDWIDE INTEGRATED STUDY OF EXTREMES (WISE).

airell
Télécharger la présentation

WORLDWIDE INTEGRATED STUDY OF EXTREMES (WISE)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. “Extremes constitute the major stress factor on a number of environmental and socio-economic systems.” (Heino et al., 1999)

  2. WORLDWIDE INTEGRATED STUDY OF EXTREMES (WISE) Objective: To better understand the occurrence, evolution and role of extremes within the climate system (and to contribute to their better prediction) • It is expected that the exact nature of the objective will evolve somewhat as the effort proceeds. • The effort is initially focusing on droughts and extended wet periods • Extremes are an important aspect of GEWEX Phase II Roadmap

  3. A FOCUS ON EXTREMES … 1995 First considered 2003 Ad hoc group to consider a working group 2004 Go-ahead for working group 2005 (July) I agreed to initially lead working group 2005 (now) Developing pragmatic plan

  4. Outline of Presentation • Objectives and Background • Initial Focal Points • Specific Examples of Extremes CEOP period Canadian Drought Initiative • Trends • Data Base for Extremes • Summary and Next Steps

  5. AN OVERALL PERSPECTIVE • What extremes have occurred? • How do extremes develop, evolve and end within the climate system? • Have extremes changed in occurrence and character? • Why did (or did not) the occurrence and characteristics of extremes change? • Given our progress, how can we contribute to assessing whether extremes may change in the future? Issue: How wide should our scope be?

  6. FOCAL POINTS It is critical to develop a small number of specific, unique and do-able actions Although complementary, two initial ones: • GHP builds on WEBS ‘products’ and other activities • CEOP one scientific component of a larger effort

  7. 1. WISE and WEBS … Extremes have always been a critical part of the GHP strategy Since: • WEBS has focused on longer-term averages • Numerous CSE-related studies have included extremes Then capitalize on these experiences: • Synthesis effort to collectively address water and energy budgets, flows and feedbacks during extremes longer period than CEOP (say 1995-2004) many relevant studies completed

  8. SPECIFIC ISSUES • What are the ‘water and energy cycling’ characteristics of extremes? • What processes and feedbacks were responsible for these evolving features in different regions?

  9. Summary of MRB Annual Water and Energy Budgets

  10. ARTICLE OUTLINE Objective of Article: Synthesize our understanding of how droughts/extended wet periods develop, evolve, and end with emphasis on factors over land areas Contents: Current information as a basis additional analyses to be determined Authorship: Multi-authors Mode of operation: Iterate …

  11. 2. WISE and CEOP Objective • Advance our understanding of extremes including their occurrence, characteristics and inter-connections. Approach: • Examine extremes individually over the CEOP period • Relate these individual events to each other as well as to the overall climate system Questions specifically associated with this approach include: • What extremes occurred during CEOP over the world? • What are the characteristics of these extremes? • How did the cycling of water and energy occur within these extremes? • To what degree were the extremes inter-connected? Outcome: • “Synthesis’ article on addressing such issues

  12. CONTRIBUTORS OF EXTREMES INFORMATION DURING CEOPand counting … Drought over Australia Alan Seed and … Heat wave over Europe Christoph Schaer plus … Flooding in NZ Warren Gray/David Wratt Extremes- South America Hugo Berbery Drought over Canada Ron Stewart and … Drought over US Rick Lawford and … Drought/floods in Asia Bill Lau/Ben Burford Brazil extremes Jose Marengo GPCC/GPCP Bruno Rudolf …

  13. 2001 2002

  14. 2003 2004 Nov/03 – Nov/04

  15. Impact of the summer 2003 in Europe Agricultural losses:12.3 Billion US$ (SwissRe estimate) Serious problems with- freshwater resources (Italy)- forest fires (Portugal)- freshwater fish (Switzerland) Shortage of electricity, peak prices on spot market (EEX, Leipzig) Estimated 22,000 to 35,000 heat deaths (excess mortality) August 2003 temperatures relative to 2000-2002, 2004 (Reto Stöckli, ETH/NASA, MODIS)

  16. 10 y 10 y 100 y 100 y mean 1000 y 1000 y Estimation of Return Periods Average of 4 Stations: Zürich, Basel, Berne, Geneva 1864-2003

  17. Anomaly 500 hPa Circulation (August 2003) Anomaly 500 hPa Circulation(17. Juli – 6. August 2003) L H L L H L H H L L H L (Grazzini et al. 2004) (Ogi et al. 2005) D’=40m Atmospheric Circulation Sequence of blocking high-pressure systems • Summer Northern Hemisphere Annular Mode, wave-number 3(Ogi et al. 2005) • Rossby wave train (Grazzini et al. 2004, Black et al. 2005, Orsolini and Nikulin 2005)

  18. NEW ZEALAND FLOODS Masterton: 17 Feb February 2004 Manawatu: 21 Feb

  19. NEW ZEALAND FLOODING • Damage estimated at $300M …probably worst flood damage on record (inflation adjusted) • Rainfall analysis suggests an over 1:150 year event on time scales up to 72 h

  20. South American Extremes Intense precipitation events The role of the Low-level jet east of the Andes

  21. A CANADIAN NATURAL DISASTER The 1999-2004 drought was one of the worst natural disasters that Canada has ever suffered! Huge impacts on: society economy ecosystems Southern Saskatchewan, April 2002

  22. IMPACTS OF THE 1999-2004 DROUGHT • GDP (01/02) - $5.8B • Employment (01/02) - 41,000 • Natural pond depth lowest on record • Largest die-back of aspen in recorded history • Negative net farm income in some provinces (1st time in 25 years) • Huge increase in forest fires • Curtailed hydroelectric power – increase in electric rates • 32 massive Saskatchewan dust storms • Thriving grasshopper populations • Farm and business bankruptcies • Failed water wells due to reduced groundwater • Surface water supplies depleted

  23. OBJECTIVE OF THE STUDY To better understand the physical characteristics of and processes influencing Canadian Prairie droughts, and to contribute to their better prediction, through a focus on the recent severe drought that began in 1999 The Team: John Pomeroy and I (co-leads) plus ~ 25 investigators

  24. OUR STRATEGY Physical-Dynamic Approach • Improve understanding and model representation of processes • Improve understanding and simulation of the whole system • Contribute to better prediction Focus • Given limited resources, important to focus on a particular period to reach ‘critical mass’ • Natural focal point is the recent catastrophic drought that can be examined with unparalleled information • Given our detailed understanding of this event, can compare it against others over the region and elsewhere at different times

  25. QUANTIFY THE DROUGHT MODIS and aerosols Observational Networks GRACE satellite Wells in South Saskatchewan

  26. CRITICAL FACTORS Snow Water Equivalent Anomaly (mm) “Hot spots” (Koster et al. 2004) Individual storm events Varying vegetation between drought and non-drought

  27. PRAIRIE HYDROLOGY DROUGHT FACTORS Localized hydrology affected by poor drainage, storage in small depressions Non-contributing areas

  28. UNDERSTAND THE DROUGHT

  29. 3. TRENDS AND EXTREMES It is not clear whether there needs to be a separate initiative on trends in extremes • Has the frequency and/or character of extremes changed over the last few decades? Why or why not? And possibly … • Will the frequency and/or character of extremes change over the next few decades? Why or why not? Considerations: pro: critical issue in many regions strong existing GHP community activities already underway (several examples here) con: being covered elsewhere? within the scope of GEWEX?

  30. Variation of annual precipitation amount over Denmark, 1874-2004 (Cappelen and Christensen 2005). BACC (7): Selected example material from chapter 2 www.gkss.de/BACC Hans-Jörg Isemer, IBS, isemer@gkss.de GHP#11, September 2005, Melbourne, Australia

  31. 4. DATA BASE FOR EXTREMES How can we document the occurrence of extremes of interest to GHP? • many web sites now on hazards (check our web site!) • individual inputs from CSEs and others Suggestion: • Data base for extremes of interest to GHP One possible step: • Using the CEOP period as a initial focus Note: This is linked with the establishment of development of robust definition(s) of extremes

  32. WISE “Guys” • BK Basu • Hugo Berbery • Ben Burford • Ole Chrstensen • Hans-Joerg Isemer • John Roads • Alan Seed • Ron Stewart • Kiyatishu Takahashi • Steve Williams • Eric Wood • and others to be added

  33. SUMMARY We are just starting our focused activity on extremes Natural initial focal point are: • building on WEBS and other studies (article ~ 3 y) • in combination with CEOP (article ~ 3-4 y) • trends A challenging issue • data base for extremes

  34. BREAK OUT • Is our present objective still appropriate? • Are our initial issues and components OK? • Should we include trends? • How do we best address ‘defining’ extremes? • To what extent should we produce an extremes data base? • What specific actions do we have (with what outcomes)? • Who leads these? • What are our timelines

  35. MEETING PLANS Potential special sessions at international conferences • Extremes session at 2006 CEOP workshop • Proposed WISE session at 2006 autumn AGU • Hydrological Cycle Symposium at IUGG 2007 (Italy) • …

More Related