Climate ScienceHow serious is the problem?

Bruce M. EverettJuly 15, 2014

The argument as portrayed in the press

YesIs climate

change real?

No

Do something

Do nothing

The real argument is much more complicated

Has the Earth warmed?

Yes.(Some debate

about numbers.)

The real argument is much more complicated

Are humans responsible?

Yes.(Not sure

how much.)

Has the Earth warmed?

Yes.(Some debate

about numbers.)

President Obama’s Tweet(May 16, 2013)

• Examined abstracts of 14,000 papers on climate.

• Did not interview authors.

• Selected 2,000 which addressed climate change.

• Concluded that 97% either:

– State that humans are the primary cause of observed global warming, or

– State or imply that humans caused some of the observed warming, but don’t say how much.

Professor Cook’s Study

http://iopscience.iop.org/1748-9326/8/2/024024/article

President Obama’s Tweet(May 16, 2013)

and, to some degree,

ˆ

The real argument is much more complicated

Are humans responsible?

Can we predict future

warming?

No!Climate system is

too complex. Scientific

understanding is insufficient.

Yes.(Not sure

how much.)

Has the Earth warmed?

Yes.(Some debate

about numbers.)

Complex Systems – Bird Swarms

Can we predict their behavior?

How do we know whether we

understand the problem?

Science!

1. Guess

2. Compute the consequences of the guess

3. Compare the computation results to nature

Nobel Laureate Richard P. Feynmanon the Scientific Method

“It doesn't matter how beautiful your guess is or how smart you are or what your name is. If it disagrees with experiment, it's wrong.”

Nobel Laureate Richard P. Feynmanon the Scientific Method

The weather gets weird. The hots are expected to get hotter, the wets wetter, the dries drier and the most violent storms more numerous..

Thomas L. FriedmanNew York Times Columnist

The weather gets weird. The hots are expected to get hotter, the wets wetter, the dries drier and the most violent storms more numerous..

Thomas L. FriedmanNew York Times Columnist

19001910

19201930

19401950

19601970

19801990

20002010

-8

-6

-4

-2

0

2

4

6

8

Palmer Drought Severity Index for US

Source: NOAA

Dry

Wet

The weather gets weird. The hots are expected to get hotter, the wets wetter, the dries drier and the most violent storms more numerous..

Thomas L. FriedmanNew York Times Columnist

19491954

19591964

19691974

19791984

19891994

19992004

20092014

0

4

8

12

16

# of Category 5 Hurricanes since 1949

Trend

Source: Unisys hurricane data base

There have been no Category 5 hurricanes in the Atlantic since September 6, 2007.

Climate computer models cannot yet make any meaningful predictions.

The atmosphere has not experienced any net warming in the last 15 years.

The UN Intergovernmental Panel on Climate Change is a committee.

Committees do politics,not science.

Science is the belief in the ignorance of experts.

                        Richard Feynman

We do not know if climate change is:

Catastrophic

Unimportant

Beneficial

How much does carbon mitigation cost?

Bruce M. EverettJuly 15, 2014

CO2 reduction

0 100%

Carbon mitigation

Easy and cheap

Harder and more

expensive

Difficult and painful

$/to

nn

e o

f C

O2

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

Easy steps

Plant a treeNegligible impact

Easy steps

Compact fluorescent lights0.4% carbon reduction

Easy steps

Change your thermostat 2°0.07% reduction

Hybrid cars ($165/mt)0.8% reduction

Harder steps

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

Hybrid cars

Harder steps

Nuclear power ($180/mt)Cost twice as much as natural gas

Safety?Public acceptance?

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

Nuclear

Harder steps

Onshore wind power ($190/mt)Cost twice as much as natural gas

Low utilizationIntermittent

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

Onshore wind

Really painful steps

Electric cars ($600/mt)Cost twice as much

Poor performance (low range)Not much reduction with today’s grid

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

Electric cars

Solar ($700/mt)Cost 4-5X as much as natural gas

Low utilizationIntermittent

Really painful steps

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

Solar

Light rail ($10,000/mt)Huge capital cost

Low ridershipSome systems save no CO2!

Really painful steps

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

Light rail

Carbon capture and sequestration (?/mt)Unproven technology

Cost and performance unknown

Really painful steps

Impact of carbon taxes

• US current emits ~5 billion metric tons of CO2 annually

• A $20/mt tax = $100 billion per year $1,000 per household

• A $200/mt tax = $1 trillion per year $10,000 per household

• A $500/mt tax = $2.5 trillion per year $25,000 per household

Question:How much should we pay to insure

against an unknown risk?

Climate ChangeWhat should we do?

Bruce M. EverettJuly 15, 2014

Effective policies require:

• A clear understanding of the issue

• A pathway to a solution

D-Day (June 6, 1944)

What does it take to win?

OECD Europe

US

Global CO2 Emissions from Energy1990 = 22 Billion tonnes

China

Source: Energy Information Administration

Rest of the World

OECD Europe

US

China

Global CO2 Emissions from Energy2013 = 33 Billion tonnes

Source: Energy Information Administration

Rest of the World

OECD Europe

US

China

Global CO2 Emissions from Energy2030 = 41 Billion tonnes

Source: Energy Information Administration

Rest of the World

UN Intergovernmental Panel on Climate Change (IPCC) proposes:

• 40-70% reduction from 2010 levels by 2050

• 1.3% to 3.0% annual reductions

40% reduction case

President Obama’s Climate Plan (“War on Coal”) would reduce 2030 global emissions by ~1%.

A contribution of 3% of the IPCC requirement.

40% reduction case

US The US nuclear revival

The EU target for 2030 is a 40% reduction versus 1990 levels.

A contribution of 8% of the IPCC requirement.

40% reduction case

EU

China and Germany, in particular, have made the clean energy transition central to their overall economic development strategies..           “The Green Industrial Revolution

and the United States”

Center for American Progress December, 2013

Germany – Electric Power Supply, 2013

Natural Gas (8%)

Nuclear (19%)

Wind (10%)

Solar (6%)Hydro (4%)

?

Germany – Electric Power Supply, 2013

Coal (53%)

Natural Gas (8%)

Nuclear (19%)

Wind (10%)

Solar (6%)Hydro (4%)

Wind +1.3 TWh

Solar +1.8 TWh

Coal +7.7 TWh

Growth 2013/2012

Wind +1.3 TWh

Solar +1.8 TWh

2013 Electric Power Supply, US vs Germany

Coal (53%)

Natural Gas (8%)

Nuclear(19%)

Wind (10%)

Solar (6%)Hydro (4%)

Coal (40%)

Natural Gas(28%)

Nuclear(20%)

Wind (4%)

Solar (<1%) Hydro (7%)

0.50 kg CO2/kWh 0.46 kg CO2/kWh

China’s CO2 emissions from coal in 2030(assuming no solar or wind)

12.1 billion mt CO2

Wind(5%)

Solar(3%)

GW 2013 2030

Wind 92 400

Solar 10 270

Projected growth

12.1 billion mt CO2 → 11.2 billion mt CO2

Equivalent to a 2% reduction in global carbon emissions

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

The European Trading System (ETS) has a

current price of ~$8/mt.

$/to

nn

e o

f C

O2

CO2 reduction

0 100%

Carbon mitigation

$20

$200

Easy

Hard

Really painful

The US Regional Greenhouse Gas Initiative

(RGGI) has a current price of ~$5/mt.

If you believe there is a problem,

show us a solution!