1. Plant Sector Workshop March 21, 2012

2. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 Motivation –Billion-dollar Disasters State of the Science –Heat and Cold Waves –Precipitation/flooding and drought –Snowstorms –Tornadoes Summary 2

3. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 3 Three more in 2011 approaching $1B 1.Late-October Northeast winter storm 2.April 19-20 Midwest and Southeast tornadoes 3.August 18-21 Midwest and East high wind & hail Three more in 2011 approaching $1B 1.Late-October Northeast winter storm 2.April 19-20 Midwest and Southeast tornadoes 3.August 18-21 Midwest and East high wind & hail NOAA/NCDC

4. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 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 http://www.ncdc.noaa.gov/oa/reports/billionz.html

5. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 5  Monitoring and Understanding Changes in Extreme Storm Statistics: State of Knowledge - Kunkel, K.E. et al. (23 others). In Review (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).

6. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 6

7. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 7 Extremes in Maximum Temperature Extremes in Minimum Temperature Percent of the U.S. with much above or below normal temperature NOAA U.S. Climate Extremes Index http://www.ncdc.noaa.gov/extremes/cei/

8. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 8 Minimum Temperature: statistically significant increase (0.05; 0.01 nearly) Minimum Temperature: statistically significant decrease (0.001) Percent of the U.S. much above normal Percent of the U.S. much below normal Maximum Temperature: not statistically significant Maximum Temperature: statistically significant decrease (0.05) (0.01 nearly) Katz, R. W., Unpublished results, 2012.

9. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 Coldest air masses in North American source regions are warming on multi-decadal timescales (Kalkstein et al. 1990; Hankes and Walsh 2011) Depending on the index used, differing conclusions about sub-continental statistical significance of change in heat/cold extremes 9 Decadal average values of heat waves (red bars) and cold waves (blue bars) indices for spells of 4-day duration exceeding the threshold for a 1-in-5-year recurrence. Adapted from Peterson, T.C. et al., 2012 (In Review). Monitoring and Understanding Changes in Heat Waves, Cold Waves, Floods and Droughts in the United States: State of Knowledge. BAMS.

10. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 10 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

11. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 11 Percent of the U.S. with much above normal 1-day heavy precipitation (>50.8mm) Annual (Jan-Dec) 1910-2011 A statistically significant increase in extremes NOAA U.S. Climate Extremes Index http://www.ncdc.noaa.gov/extremes/cei/

12. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 12 Differences between two periods (1990-2009 minus 1971-1989) 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

13. 13 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: 1909-2008 Difference in Number of Months with Moderate to Extreme Drought 85-127 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.

14. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 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) 14 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.

15. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 15 15 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.

16. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 16 NOAA U.S. Climate Extremes Index http://www.ncdc.noaa.gov/extremes/cei/

17. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 17 Number of extreme snowstorms (upper 10 percentile) 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% For the storms of record, the average temperature was below normal for each region Every region had two of the five storms of record occurring during seasons with above average temperatures Frequency Precipitation (Average Anomalies) Kunkel, K.E., et al., 2012 (In Review). BAMS.

18. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 18 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.

19. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 19 For continental U.S. severe tornadoes (L≥10 km), (top) total path length per year, and (bottom) the number per year r² = 0.1269 r² = 0.27 Malamud, B. D. and D. L. Turcotte, 2012. Statistics of severe tornadoes and severe tornado outbreaks. Atmos. Chem. Phys. Discuss. Length per year (km/yr) Number per year

20. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 20 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.

21. MIT – Progress on the Science of Weather and Climate ExtremesMarch 29, 2012 Widely varying suitability of our data and physical understanding of various extreme events 21 Adapted from Lubchenco, J., and T. Karl, 2012. Predicting and managing extreme weather events. Physics Today.

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