6/9/2010 1NASA image of the atmosphere

Public PerceptionPublic Perceptionandand

ScienceScienceofof

Climate ChangeClimate ChangeSenior Statesmen of VirginiaSenior Statesmen of Virginia

Robert McGrath6/9/2010 2

Points to this talkPoints to this talk• State of the politics and public attitude.• Facts about what humans are doing to the

atmosphere. • Primer on Climate Science• Silliness and Hyperbole • Conclusion

– Brief summary on science and overview of costs of policy actions

– Thoughts on what needs to happen…

36/9/2010

Politics/Public Attitude 4

Politics and Public AttitudePolitics and Public Attitude•G20 leaders on record as accepting IPCC climate projections and the need to reduce GHG levels to hold ΔT to 2 oC (compared to pre- industrial era)

•U.S. political situation: President and House have declared GHG reduction goals of 20% by 2020 and 83% by 2050 (compared to 2005).

•House passed resolution (HR2454) last summer; very heavy slogging ahead in Senate. [Vote on “resolution of disapproval of EPA findings” tomorrow!]

•Copenhagen (December 2009): confirmed proposals give ∆T ≈ 4 oC6/9/2010

Is there solid evidence the earth is warming? (percent who said YES) 71% (4/08) 57% (10/09)

because of human activity?

Entire sample: 47% 36%

Republicans: 27% 18%

Democrats: 58% 50%

Independents: 50% 33%Pew Research Center (10/09)

Policy options for addressing climate change? (percent strongly supporting)

Increased Fossil Fuel Taxes 18%

Increased Gasoline Taxes 10% Miller Center Survey (9/08)

What does the U.S. public think?What does the U.S. public think?

6Politics/Public Attitude

How does the public know what it thinks?How does the public know what it thinks?•Media…loves sound bites, controversy, catastrophe, potential catastrophes

•Internet…Google “climate change” get 22 million hits! Many of them for partisan cheerleading and mudslinging… the climate wars!

Alarmists Skeptics

Fundamentalists Deniers

Hysterics Traitors

•Movies… e.g. Al Gore’s An Inconvenient Truth

•Reports… e.g. from IPCC, and U.S. Climate Change Research Program

•U.S. political leadership… ?Bottom line…lots of talk such as: “what’s the big deal…it’s been hotter or colder before, it’s nature”, or “so what does Al Gore have to say about all this snow?”

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Politics/Public Attitude 77

Politics and views on climate science tend to be Politics and views on climate science tend to be correlatedcorrelated

Some striking quotes from politicians:

• The theory of global warming… is a very dangerous theory (Vaclav Klaus, Czech Rep. 2007)

• They are about to impose a communist world government on the world. You have a president who has very strong sympathies with that point of view. (Lord Christopher Monckton 2009)

• I called the threat of catastrophic global warming the "greatest hoax ever perpetrated on the American people," a statement that, to put it mildly, was not viewed kindly by environmental extremists and their elitist organizations. (James Inhofe Senate floor speech 2005)

• The evidence that humans are causing global warming is overwhelming and undeniable (Al Gore, An Inconvenient Truth, 2006)

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Politics/Public Attitude 88

Climate scientists:Climate scientists:

• The extent of unfounded skepticism… is dangerous…those who still think this is all a mistake or a hoax need to think again. (John Holdren 2008)

• There’s enough carbon in the ground to really cook us. (Steven Chu)

• If there’s no action before 2012, that’s too late…this is the defining moment. (Rajendra Pachauri 2007)

• Chairmen of fossil-fuel companies should be “tried for high crimes against humanity and nature.” Freight trains carrying coal are “death trains.” (James Hansen)

As advocates/activists…

6/9/2010

As (somewhat) inept advocates…“The IPCC reports have underestimated the pace of

climate change while overestimating societies' abilities to curb greenhouse gas emissions.”

9Politics/Public Attitude6/9/2010

( from Science Magazine editorial and accompanying photo (5/7/2010))

“Instantly” substituted illustration (no Photoshop, from National Geographic)

10Politics/Public Attitude6/9/2010

11Humans and Atmosphere

Millions of M

etric Tons of CO

2

from U.S. EPA

COCO22: How much do we emit: How much do we emit? ?

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12Humans and Atmosphere

COCO22: what happens to it?: what happens to it?

(from Keeling, Scripps Inst. Of Oceanography)

Baseline for most of Industrial Age is 280 ppmv)

13Humans and Atmosphere

Earth diameter = 8,000 miles, and Atmosphere pressure = 14.7 lbs/sqin So… atmosphere weighs about 5.9 million billion tonsThe weight of the “Human” CO2 adds up to about 2.0 thousand billion tonsIf all this CO2 stayed in the atmosphere, CO2 concentrations would increase by 220 parts per million (volume)

COCO22: how much of what we emit stays in the : how much of what we emit stays in the atmosphere?atmosphere?

Conclusion: oceans plus biosphere have absorbed only about ½ of “human” CO2 up until now.

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14Climate Science Primer

Climate science: historical temperature recordsClimate science: historical temperature records

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15Climate Science Primer

Climate science: weather, climate and modelingClimate science: weather, climate and modeling• Earth’s temperature determined by balance between

incoming solar radiation and outgoing heat radiation.

• GHG’s e.g., CO2, (or H2O) act as “leaky” blanket. Earth’s average temperature + 16 o C. (-18 oC without GHG’s.)

• Movements of energy and masses of air make weather and climate:– equatorial regions get more sun than polar regions,– land, ice, and water reflect the sun’s energy differently,– oceans take longer to heat (or cool) than land.

• AOGC Models try to treat the entire coupled system: atmosphere+ oceans+ land.– Complicated – Many approximations!

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16Climate Science Primer

Figure SPM.5

IPCC 2007 report (central result)A2 scenario: temps go

up somewhere between 2.0 and 5.4 oC

Model predictions for the next 100 years: how Model predictions for the next 100 years: how accurate are they likely to be?accurate are they likely to be?

Even more fun!Equilibrium temperature increases somewhere between

4.2 and 9.4 oC with the full “dose” of CO2. 6/9/2010

17Climate Science Primer

Model predictions for the next 100 years: how Model predictions for the next 100 years: how accurate are they likely to be?accurate are they likely to be?

• IPCC averages model results to get the so-called most likely answers.

• These models are darned complicated.• When CO2 goes up, water vapor (powerful GHG!)

goes up. • BUT what does the water vapor do? • The models disagree considerably over the fate of

the extra water vapor.• Also considerable uncertainty about influence of

human-caused aerosols in the atmosphere.

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18Climate Science Primer

Clouds vs. more water vapor… biggest feedback uncertainty

Model predictions for the next 100 years: how Model predictions for the next 100 years: how accurate are they likely to be?accurate are they likely to be?

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Climate Science Primer 19

Is the recent past temperature record understood? Is the recent past temperature record understood?

Slope = 0.7 0C/century

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20Climate Science Primer

from Lean and Rind, Geophysical Res. Letters (2009)

Is the recent past temperature record understood?Is the recent past temperature record understood?

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21Silliness and Hyperbole

Perpetrators:Gore movie, media in general, some scientists

Downplay uncertainties Assume warming means human-caused warming. Extreme events (e.g. hurricanes) “show” models are right.

Skeptics “models aren’t evidence” CO2 is “good” for us

CO2 lag as temperature increases during interglacials (Gore movie) shows CO2 doesn’t have anything to do with temperature increase “something else has caused it… the computer models don’t know what it is.”

Lack of warming in recent years means global warming is much ado about nothing or even a hoax.

Silliness and hyperboleSilliness and hyperbole

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22Silliness and Hyperbole

from An Inconvenient Truth (2006)

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23Silliness and Hyberpole

(data from NOAA/NCDC)

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shown in shown in An Inconvenient TruthAn Inconvenient Truth

24Silliness and Hyperbole

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

50,000

1900 1908 1916 1924 1932 1940 1948 1956 1964 1972 1980 1988 1996 2004

Al Gore showed a version of this:Al Gore showed a version of this:

Hurricane damages (in dollars) by yearHurricane damages (in dollars) by year

from Piekle, Landsea et al. (2007)

6/9/2010

25Silliness and Hyperbole

0

20,000

40,000

60,000

80,000

100,000

120,000

1900 1908 1916 1924 1932 1940 1948 1956 1964 1972 1980 1988 1996 2004

AdjustedAdjusted Hurricane damages by year Hurricane damages by year

from Piekle, Landsea et al.6/9/2010

26Silliness and hyperbole

0

5

10

15

20

25

1900-19091910-19191920-19291930-19391940-1949 1950-19591960-19691970-19791980-19891990-1999

All Categories Category 4 & 5

Hurricanes striking U.S. mainland Hurricanes striking U.S. mainland

from Landsea (NOAA)

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Conclusion 27

Summary about the science…Summary about the science…We’re in a warming period, but so far not very dramatic.

Observations are consistent with warming being due to increasing GHG’s.

NAS’s America’s Climate Choices: "Climate change is occurring, is caused largely by human activities, and poses significant risks for — and in many cases is already affecting — a broad range of human and natural systems“ (May 2010)

Model predictions have large uncertainties.

Uncertainties make public decision making and actions even harder.

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Conclusion 28

Policy questions/choices…Policy questions/choices…

Do nothing.

Ask what’s the society cost of transitioning from fossil fuels to other energy sources compared to the cost of doing nothing? Escalate the modeling!

Combine models about economics with models about climate.

Get answers accompanied by more uncertainties.

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Conclusion 29

Analysis Outcome∆ T ≤ (oC)

C cost in 2020 per ton

(2005 $)

C cost in 2050 per ton

(2005 $)Stern (LSE-UK) 1.5 372 594

Nordhaus (Yale) 2.5 48 90

Nordhaus 2.0 87 267

Energy Modeling Forum (Stanford led)

2.0 (HR 2454)

15 ↔ 30 65 ↔ 135

48

Gas up 13 ¢ per gallon; electricity up 1.4 ¢ per kw-hr (coal produced) Nation’s tax bill up 75 B$ [compare 188 B$ imported oil bill (2009)]

6/9/2010

Example results from these combined economics-climate Example results from these combined economics-climate modelsmodels

30Conclusion

Majority climate science community needs to be candid and innovative in helping the public understand the situation recognizing:

Evidence of human caused warming up until now is obscure.There remain huge uncertainties in the modeling (e.g., fate of water vapor, contribution of human caused aerosols) Warming over last 100 years is only about 40% of what it would have been with standard climate “sensitivity” and NO aerosols.Modeling is essential, improvements in modeling and in data gathering are making predictions more reliable.

Skeptics have burden to show why the AOGCM’s can safely be dismissed.“Outlaw” hyperbole, distortions, silliness, ad hominem arguments Intelligent public discussion has to be the basis for intelligent public policy! Is it possible?

6/9/2010

Thoughts of what needs to happen…Thoughts of what needs to happen…

Conclusion 316/9/2010 31

Circa early 1950’s: 2004: