IGES Executive Roundtable on Climate April 25, 2012

IGES Executive Roundtable on ClimateApril 25, 2012 ©Warren Faildey -Weatherstock.comr Billion-dollar Disasters Changes in Extremes –Heat and Cold Waves –Precipitation/flooding and drought –Snowstorms –Tornadoes Summary 2

IGES Executive Roundtable on ClimateApril 25, Three more in 2011 approaching $1B 1.Late-October Northeast winter storm 2.April Midwest and Southeast tornadoes 3.August Midwest and East high wind & hail Three more in 2011 approaching $1B 1.Late-October Northeast winter storm 2.April Midwest and Southeast tornadoes 3.August Midwest and East high wind & hail NOAA/NCDC

IGES Executive Roundtable on ClimateApril 25, 2012 Since 1980, 114 billion-dollar weather and climate disasters in U.S. Total losses since 1980 of billion-dollar disasters exceed $800 billion. Is the U.S. becoming more exposed and/or sensitive to severe events? A Record 14 Disasters in the U.S. in 2011 Three more approaching $1B A Record 14 Disasters in the U.S. in 2011 Three more approaching $1B 4 NOAA Billion-Dollar Disasters

5 Monitoring and Understanding Changes in Extreme Storm Statistics: State of Knowledge - Kunkel, K.E. et al. (23 others). Tentatively accepted (BAMS). Monitoring and Understanding Changes in Heat Waves, Cold Waves, Floods and Droughts in the United States: State of Knowledge - Peterson, T.C. et al. (27 others). In Review (BAMS). Monitoring and Understanding Changes in Extreme Winds, Waves, and Extratropical Storms along the Coasts: State of Knowledge - Vose, R.S. et al. (25 others) To be submitted (BAMS).

IGES Executive Roundtable on ClimateApril 25, Katz, R. W., Unpublished results, Percent of the U.S. much above normal Percent of the U.S. much below normal Not statistically significant Maximum Temperatures Minimum Temperatures

IGES Executive Roundtable on ClimateApril 25, Hansen, J. et al., 2012 (submitted). Public Perception of Climate Change and the New Climate Dice. Proceedings of the National Academy of Science. Normalized Departures

IGES Executive Roundtable on ClimateApril 25, Percent of the U.S. with much above normal 1-day heavy precipitation (>50.8mm) Annual (Jan-Dec) A statistically significant increase in extremes NOAA U.S. Climate Extremes Index

IGES Executive Roundtable on ClimateApril 25, Differences between two periods ( minus ) for daily, 1-in-5yr extreme events and coincident (spatial and temporal) precipitable water values Extreme Precipitation Frequency Index Difference (Percent) Precipitable Water Difference (Percent) Adapted from Kunkel, K.E. et al., 2012 (In Review). Monitoring and Understanding Changes in Extreme Storm Statistics: State of Knowledge. BAMS. All changes positive

10 Regional similarities between trends of annual precipitation, droughts, and extremes of river flooding Regional similarities between extremes of river flooding and extremes of precipitation is not as congruent River-Flow Trends in Annual Maximum Trends in Total Annual Precipitation: Difference in Number of Months with Moderate to Extreme Drought years ending 2008 Peterson, T. C. et al., 2012 (In Review). Monitoring and Understanding Changes in Heat Waves, Cold Waves, Floods and Drought in the United States: State of Knowledge. BAMS.

IGES Executive Roundtable on ClimateApril 25, 2012 Widespread persistent drought 1930s (Central and Northern Great Plains, Northwest, Great Lakes) 1950s (Southern Plains, Southwest), 1980s (West, Southeast) First decade of the 21 st century (West, Southeast) 11 Trends (% per century) 1900 to 2011: -0.1% 1930 to 2011: -10.0% 1971 to 2011: +31.6% Peterson, T. C. et al., 2012 (In Review). Ibid.

IGES Executive Roundtable on ClimateApril 25, Climate Models Global Climate Change Impacts in the United States, Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson, (eds.). Cambridge University Press, 2009.

IGES Executive Roundtable on ClimateApril 25, NOAA U.S. Climate Extremes Index

IGES Executive Roundtable on ClimateApril 25, Number of extreme snowstorms occurring each decade within the six U.S. climate regions in the eastern two-thirds of the contiguous U.S. Most severe storms for each of the six climate regions from 1900 to 2010 Temperature Anomalies During Season of Extreme Events Precipitation Anomalies During Season of Extreme Events -1% -9% 19% 5% -6% 8% Every region had two of the five storms of record occurring during seasons with above average temperatures Frequency Kunkel, K.E., et al., 2012 (Tentatively Accepted). BAMS.

IGES Executive Roundtable on ClimateApril 25, Although some ingredients that are favorable for severe thunderstorms have increased over the years, others have not Overall, changes in the frequency of environments favorable for severe convective storms have not been statistically significant U.S. Annual Tornadoes Kunkel, K.E., et al., 2012 (In Review). BAMS.

IGES Executive Roundtable on ClimateApril 25, For continental U.S. severe tornadoes (L10 km), (top) total path length per year, and (bottom) the number per year r² = r² = 0.27 Malamud, B. D. and D. L. Turcotte, Statistics of severe tornadoes and severe tornado outbreaks. Atmos. Chem. Phys. Discuss. Length per year (km/yr) Number per year

IGES Executive Roundtable on ClimateApril 25, Wind Shear vs. Vertical Velocity–6km proximity values Each cell is best viewed as a conditional probability Kunkel, K.E., et al., 2012 (In Review). BAMS.

IGES Executive Roundtable on ClimateApril 25, 2012 Widely varying suitability of our data and physical understanding of various extreme events 18 Adapted from Lubchenco, J., and T. Karl, Predicting and managing extreme weather events. Physics Today.

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