"Extreme Weather in the Coming Decades What is the Role of Climate Change?"

Transcription

1 "Extreme Weather in the Coming Decades What is the Role of Climate Change?" Thursday September pm By Roger A. Pielke Sr. University of Colorado, Boulder TD Canada ada Trust Walter ate Bean Public Lecture e Waterloo, Ontario, Canada

2 2007 IPCC Report

3 The 2007 IPCC perspective focuses on CO2 and a few other greenhouse gases as the dominate human climate forcing. Global warming is the central theme of their perspective. The IPCC starts with a top down global perspective to regional and local vulnerability to climate change.

4 2007 IPCC Radiative forcings Without Feedbacks

5 Carbon Dioxide

6

7 Aerosols

8 From Industrial Emissions

9

10 From Biomass Burning

11

12 Nitrogen deposition

13 Land Use/Land Cover Change

14

15

16

17 The human influence on climate is everywhere!

18 However, It Is Much hmore Than CO2 and a Few Other Greenhouse Gases

19 First, However, What Do The Latest Multi Decadal Climate Metrics Tell Us About Trends and Anomalies?

20 Global Average Lower Troposphere and Lower Stratosphere Trends 1979 to 2011

21 RSS MSUTemperature Weighting Functions

22

23 Sea Surface Temperature Anomalies and Long Term Trend

24

25

26 Upper Ocean Heat Trends

27

28 Arctic Sea Ice Trends

29

30

31

32

33 Antarctic Sea Ice Trends

34

35

36

37

38 Sea Level Trends

39

40 Hurricane Variations Over Time

41

42

43 Western Russia Heat Wave Of 2009

44 and russian heat wave.html

45 R. Dole, M. Hoerling, J. Perlwitz, J. Eischeid, P. Pegion, T. Zhang, X. W. Quan, T. Xu, and D. Murray (2011), Was there a basis for anticipating the 2010 Russian heat wave?, Geophys. Res. Lett., 38, L06702, doi: /2010gl Our analysis points to a primarily il natural cause for the Russian heat wave. This event appears to be mainly due to internal atmospheric dynamical processes that produced and maintained an intense and long lived blocking event. Results from prior studies suggest that it is likely that the intensity of the heat wave was further increased by regional land surface feedbacks. The absence of long term trends in regional mean temperatures and variability together with the model results indicate that it is very unlikely that warming attributable to increasing greenhouse gas concentrations contributed substantially to the magnitude of this heat wave.

46 Tornadoes

47 Tornado Damage Image from blogspot.com

48

49

50 Observed Climate And Social Mti Metrics Indicate A Very Complex Climate System That Is Not Properly Defined By The Concept Of Global Warming

51 The Data Suggests That Extreme Weather Events Are Not Increasing, But This Is A Topic Area Of Intense Scrutiny With Conflicting Conclusions. A Challenge Is To Ferret Out The Societal Changes From Weather Changes.

52 Now Lets Do Some Climate Physics

53 Global warming involves the accumulation of heat in Joules within the components of the climate system. This accumulation is dominated by the heating and cooling within the upper layers of the oceans.

54 Global Warming = Radiative forcings + Radiative feedbacks Global Warming = A Positive Radiative Imbalance

55 From Ellis et al. 1979

56 From JimHansen, 2005 Our simulated heat storage rate was 0.6 W/m2 in the upper 750 m of the ocean The decadal mean planetary energy imbalance, 075W/m W/m2, includes heat storage in the deeper ocean and energy used to melt ice and warm the air and land. 085W/m is the imbalance at the end of the decade.

57 Upper 750 m Ocean Global Annual Average Heating Hansen from the GISS model 06W 0.6 Watts per meter squared Willis from observations 062Watts 0.62 per meter squared Willis (preliminary) 0.16 Watts per meter squared

58 Muted Global Warming The global annual average upper ocean heating rate in the last 7 years is about ¼ of that for the previous decade In other words, global warming has been about 25% of that in the previous decade. The heating rate will need to be about quadruple this rate in in order to catch up with the model predictions in the next 7 years.

59 Where Is The Extra Heat? Deeper In the oceans? Lost to Space? Melting Glaciers? Being Absorbed By Land? Absorbed In The Atmosphere?

60 Global Warming Is More Complex Than Reported In The Media And In The 2007 IPCC Climate Assessment

61 Climate Change, However, Is Much More Than Global Warming

62 Climate Change is any multi decadal or longer alteration in one or more physical, chemical and/or biological components of the climate system. Climate change includes, for example, changes in fauna and flora, snow cover, etc which persist for decades and longer. Climate variability can then be defined as changes which occur on shorter time periods. Climate Is Much More Than Climate Change Indeed Climate Is Much More Than Climate Change. Indeed, the addition of the word Change is redundant. Climate is always changing, just like the weather

63 Source: National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. titi

64 Human Climate Forcings The influence of the human input of CO2 and other greenhouse gases on regional and global radiative heating The influence of human caused aerosols on regional (and global) radiative heating The effect of aerosols on clouds and precipitation The influence of aerosol deposition (e.g. soot; nitrogen) on climate The effect of land cover/ land use on climate The biogeochemical effect of added atmospheric CO2

65 What About Extreme Weather? Is It Increasing as a Result Of The Diverse Range of Human Climate Forcings?

66 Is There Evidence Of A Human Role In Extreme Events? YES However.

67 What Are The Human Influences? Global Average Changes In The Heat Content Of The Climate System (e.g. Global Warming ) From Added CO2 and A Few Other Greenhouse Gases? Land Use/Land cover Change? AerosolsFrom Biomass Burning Aerosols From Industrial and Vehicular Emissions (soot; sulfates, etc.) Natural Climate Variability? Increased Exposure Of Society?

68 Hypothesis 1: Human influence on regional climate variability and changeis of minimal importance, and natural causes dominate climate variations and changes on all time scales. In coming decades, the human influence will continue to be minimal. Hypothesis 2a: Although the natural causes of regional climate variations and changes are undoubtedly important, the human influences are significant and involve a diverse range of first order climate forcings, including, but not limited to, the human input of carbon dioxide (CO2). Most, if not all, of these human influences on regional and global climate will continue to be of concernduring the coming decades. Hypothesis 2b: Although the naturalcauses of regional climate variations and changes are undoubtedly important, the human influences are significant and are dominated by the emissions into the atmosphere of greenhouse gases, the most important of which is CO2. The adverse impact of these gases on regional climate constitutes the primary climate issue for the coming decades. [IPCC] Hypotheses 1 and 2b, however, are inaccurate characterizations of the climate system.

69 Hypothesis 1: Human influence on regional climate variability and changeis of minimal importance, and natural causes dominate climate variations and changes on all time scales. In coming decades, the human influence will continue to be minimal. Hypothesis 2a: Although the natural causes of regional climate variations and changes are undoubtedly important, the human influences are significant and involve a diverse range of first order climate forcings, including, but not limited to, the human input of carbon dioxide (CO2). Most, if not all, of these human influences on regional and global climate will continue to be of concernduring the coming decades. Hypothesis 2b: Although the naturalcauses of regional climate variations and changes are undoubtedly important, the human influences are significant and are dominated by the emissions into the atmosphere of greenhouse gases, the most important of which is CO2. The adverse impact of these gases on regional climate constitutes the primary climate issue for the coming decades. [IPCC] Hypotheses 1 and 2b, however, are inaccurate characterizations of the climate system.

70 Hypothesis 1: Human influence on regional climate variability and changeis of minimal importance, and natural causes dominate climate variations and changes on all time scales. In coming decades, the human influence will continue to be minimal. Hypothesis 2a: Although the natural causes of regional climate variations and changes are undoubtedly important, the human influences are significant and involve a diverse range of first order climate forcings, including, but not limited to, the human input of carbon dioxide (CO2). Most, if not all, of these human influences on regional and global climate will continue to be of concernduring the coming decades. Hypothesis 2b: Although the naturalcauses of regional climate variations and changes are undoubtedly important, the human influences are significant and are dominated by the emissions into the atmosphere of greenhouse gases, the most important of which is CO2. The adverse impact of these gases on regional climate constitutes the primary climate issue for the coming decades. [IPCC] Hypotheses 1 and 2b, however, are inaccurate characterizations of the climate system.

71 As Mike Hulme of the University of East Anglia writes of two views: 1) The overwhelming scientific evidence tells us that human greenhouse gas emissions are resulting in climate changes that cannot be explained by natural causes. Climate change is real, we are causing it, and it is happening right now. now or 2) The overwhelming hl scientific ifi evidence tells us that human greenhouse gas emissions, land use changes and aerosol pollution are all contributing to regional and global climate changes, which exacerbate the changes and variability in climatesbrought about by natural causes. Because humans are contributing to climate change, it is happening now and in the future for a much more complex set of reasons than in previous human history. As Mike Hulme writes.thesetwodifferent two provocations twodifferent framingsof climatechange change open up the possibility of very different forms of public and policy engagement with the issue. They shape the response. been framed six new ways to understand climate change 2119

72 Damage and Property Loss Are Dominated dby Societal lchanges

73 Pielke, Jr., R. A., Gratz, J., Landsea, C. W., Collins, D., Saunders, M. A., and Musulin, R., Normalized Hurricane Damages in the United States: Natural Hazards Review, 9, 1,

74 there are no trends in normalized.html

75 How Vulnerability Can Change Over Time

76 A New Approach Is Needed! We Need To Replace The IPCC Top Down Approach hto Predict Future Environmental And Social Risk With A Bottom Up Resource Based Assessment of Vulnerability Our Key Resources Are Water, Food, Energy, Ecosystem Function and Human Health

77 O'Brien, K. L., S. Eriksen, L. Nygaard, and A. Schjolden, (2007), Why different interpretations of vulnerability matter in climate change discourses. Climate Policy 7 (1): 73 88

78

79 Questions For Stakeholders On The Bottom Up Approach h i hi i? i i d? 1. Why is this resource important? How is it used? To what stakeholders is it valuable? 2. What are the key environmental and social variables that influence this resource? 3. What is the sensitivity of this resource to changes in each of these key variables? (This may include but is not limited to, the sensitivity of the resource to climate variations and change on short (days); medium (seasons) and long (multi decadal) time scales).

80 4. What changes (thresholds) in these key variables 356 would have to occur to result in a negative (or positive) outcomefor thisresource? 5. What are the best estimates of the probabilities for these changes to occur? What tools are available to quantify the effect of these changes? Can these estimates be skillfully predicted? 6. What actions (adaptation/mitigation) can be undertaken in order to minimize or eliminate the negative consequences of these changes (or to optimize a positive response)? 7. What are specific recommendations dti for policymakers and other stakeholders?

81 This bottom up vulnerability perspective concept requires the determination of the major threats to local and regional water, food, energy, human health, and ecosystem function resources from extreme events including climate, but also from other social and environmental issues. After these threats are identified for each resource, then the relative risks can be compared with other risks in order to adopt optimal preferred mitigation/adaptation strategies.

82

83 Thank You for the opportunity to speak to you this evening!

84 Roger Pielke Sr. Research Websites

85 Background Photograph Courtesy of Mike Hollingshead index.htm