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Extreme Events. How are they related to global trends?. Key Points. Extreme Events have been closely linked to GHG emissions. Extreme Events are very variable and are difficult to model. Extreme Events have many impacts and we should get well prepared!. What are they?.
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Extreme Events How are they related to global trends?
Key Points • Extreme Events have been closely linked to GHG emissions. • Extreme Events are very variable and are difficult to model. • Extreme Events have many impacts and we should get well prepared!
What are they? • “There are a number of ways extreme climate events can be defined, such as extreme daily temperatures, extreme daily rainfall amounts, large areas experiencing unusually warm monthly temperatures, or even storm events such as hurricanes. Extreme events can also be defined by the impact an event has on society. That may involve excessive loss of life, excessive economic or monetary losses or both.” (Easterling et al. 2000)
Key points about Extreme Events (and Global Trends) • 1) Extreme Events are linked with anthropogenic emissions and GHGs (Milly et al., Oki et al amongst others) “The change in the area of the USA affected by increases in the proportion of total annual precipitation derived from extreme daily precipitation events (more than 2 inches)” source:http://climate.dot.gov/images/precip2.gif
Key points • 2) Extreme Events are increasingly variable and difficult to model (MacCracken, Milly, Palmer…) • http://earthobservatory.nasa.gov/Study/RisingCost/Images/extreme_events_mid.gif
3) Extreme Events have many repercussions and impacts… What should we do? http://www.epa.gov/climatechange/effects/extreme.html Key Points
Literature… Observed variability and trends in extreme climate events: A brief review DR Easterling, JL Evans, PY Groisman, TR Karl, KE … - Bulletin of the American Meteorological Society, 2000 - agci.org Easterling, DR and co-authors, 2000. Observed climate variability and change of relevance to the biosphere. Journal of Geophysical Research-Atmos., 105 (D15): 20101-20114. Meehl, GA and C. Tebaldi, 2004. More intense, more frequent, and longer lasting heat waves in the 21st century. Science, 305 (5686): 994-997. Stott, PA, DA Stone and MR Allen, 2004. Human contribution to the European heat wave of 2003. Nature, 432 (7017): 610-614. Groisman, PY and co-authors, 2004. Contemporary changes of the hydrological cycle over the contiguous United States: Trends derived from in situ observations. Journal of Hydrometeorology, 5 (1): 64-85 Groisman, PY, WE Knight and TR Karl, 2001. Heavy precipitation and high streamflow in the contiguous United States: Trends in the twentieth century. Journal of Climate, 82 (2): 219-246.
Literature Palmer, TN and J Raisanen, 2002. Quantifying the risk of extreme seasonal precipitation events in a changing climate, Nature, 415: 512-514. Milly, PCD and co-authors, 2002. Increasing risk of great floods in a changing climate, Nature, 415: 514-517. MacCracken, MC and co-authors, 2003. Climate change scenarios for the US National Assessment. Bulletin of the American Meteorological Society, 84 (12): 1711 Major, D. and R. Goldberg. 2001. Water Supply. In: Rosenzweig, C. and W.D. Solecki (Eds.) 2001. Climate Change and a Global City: The Potential Consequences of Climate Variability and Change – Metro East Coast. New York: Columbia Earth Institute. p. 87-101 Taikan Oki and Shinjiro Kanae Science in www.sciencemag.org August 2006 Global Hydrological Cycles and World Water Resources”