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Global Climate Change

David KaroweDepartment of Biological Sciences

Western Michigan University

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14 warmest years in history: 2001-2013, 1998*

Warming is 10-20 times faster than in at least the last 800,000 years

Since 1900, Earth has warmed ~ 0.8o C

*

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Temperature difference relative to 1950-1980

http://data.giss.nasa.gov/gistemp/animations/

1950-1959

At the same time, much of the world has been experiencing more frequent and stronger droughts

Palmer Drought Severity Index (PDSI)

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1950-19592000-2009

At the same time, much of the world has been experiencing more frequent and stronger droughts

Palmer Drought Severity Index (PDSI)

mild

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Much of the U.S. has been experiencing severe drought

September 2012 77% drought

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April 1: 53% drought

Is the U.S. still in drought?

January 2014 Temperatures

This winter, most of the world was not like Michigan

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“Natural variation” cannot explain current warming

1900 1925 1950 1975

Temperature

Solar Irradiance

Recently, while Earth has been warming fastest, solar irradiance has been decreasing

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In two major ways, current warming is very different than any warming period

in at least the last 800,000 years

1. It’s at least 10-20 times faster

2. It’s happening while solar input is decreasing

Best estimate: > 95% of current warming is due to human activities

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Are Americans aware of the cause?

“We’re causing it”

“It’s natural”

Is there any debate among scientists about whether humans are the primary cause of global warming?

“Most of the global warming in recent decades can be attributed to human activities."

Scientific organizations endorsing this statement:

United States:National Academy of SciencesAmerican Medical AssociationAmerican Association for the Advancement of ScienceAmerican Meteorological SocietyAmerican Institute of Biological SciencesAmerican Chemical SocietyAmerican Geophysical UnionAmerican Institute of Physics

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Geological Society of AmericaAmerican Academy of PaediatricsAmerican College of Preventive MedicineAmerican Public Health AssociationNational Oceanic and Atmospheric Administration National Aeronautics and Space Administration Environmental Protection Agency National Center for Atmospheric ResearchUniversity Corporation for Atmospheric ResearchEcological Society of AmericaAmerican Society of AgronomyAmerican Society of Plant BiologistsAssociation of Ecosystem Research CentersBotanical Society of AmericaCrop Science Society of AmericaNatural Science Collections Alliance

American Statistical AssociationOrganization of Biological Field StationsAmerican Physical SocietySociety for Industrial and Applied MathematicsSociety of Systematic BiologistsSoil Science Society of AmericaFederation of American ScientistsNational Research CouncilNational Association of Geoscience TeachersAmerican Quaternary AssociationAmerican Association of Wildlife VeterinariansAmerican Society for MicrobiologySociety of American ForestersAmerican Astronomical Society

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Europe:European Academy of Sciences and ArtsEuropean Science FoundationEuropean Geosciences UnionEuropean Physical SocietyEuropean Federation of GeologistsNorwegian Academy of Science and LettersRoyal Society of the United KingdomAcademie des Sciences (France)Deutsche Akademie der Naturforscher (Germany)Accademia dei Lincei (Italy)Royal Irish AcademyRoyal Swedish Academy of SciencesRoyal Academy of Belgium for Sciences and the ArtsRoyal Meteorological SocietyBritish Antarctic Survey

Other countries (≥ 35):Chinese Academy of SciencesScience Council of JapanRussian Academy of SciencesIndian National Science AcademyRoyal Society of New ZealandAustralian Academy of SciencesAustralian Medical AssociationPolish Academy of SciencesAcademia Brasiliera de Ciencias (Brazil)Royal Society of CanadaAfrican Academy of SciencesCaribbean Academy of SciencesAcademy of Sciences of MalaysiaIndonesian Academy of SciencesAcademy of Science of South Africa

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Scientific organizations holding a dissenting opinion:

American Institute of Petroleum Geologists

2007:

Since 2008:None

Are Americans aware of the strength of the scientific consensus?

“Scientists agree”

“Scientists don’t agree”

In fact, 97.5% of climate scientists agree

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What does the future hold?

It depends on our choices

2o

4o

Depending on choices we make, Earth is likely to warm by

2-5o Cby 2100

“Business as usual”

Alternate energy sources

Actual

If we remain on our current course, future climate change will be severe

5o

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Lower Emissions

Higher Emissions

And warming will be greater at higher latitudes

Will a 5o temperature rise matter?When Earth was 5o cooler:

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Most summers are likely to be hotter than any experienced thus far

Most summers are likely to be hotter than any experienced thus far

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Michigan will experience many more days over 90o F

2060-2069

Palmer Drought Severity Index (PDSI)

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- current drought indices will longer be sufficient

Much of the world is likely to experience much more frequent and stronger droughts by the 2060s

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How will climate change affect species?

Again, it depends on our choices

If we remain on our current course, there will be serious adverse consequences for most species

With 2o warming: 40% of 5,200 African plant species are predicted to go extinct

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Climate change is predicted to cause the extinction of 20-40% of large African mammals by 2080

Coral reef species are particularly vulnerable

because both warming and ocean acidification can cause bleaching

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Even 2o warming is likely to cause a massive increase in bleaching events

How will climate change affect species in Norway?

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Some bird species in Norway are migrating earlier

Snow Bunting

Red Knot

Ringed Plover

Sedge Warbler

- but others are not

Scandinavian bird species are predicted to lose 80% of their suitable habitat by 2080

Many Norwegian birds are likely to lose habitat

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All of Norway’s mountain bird species are predicted to be “climate losers”

Mountain plants in Norway are likely to be less sensitive to climate change than elsewhere in Europe

- extinction predicted for only 10% of alpine species in the Norwegian Scandes (50% extinction elsewhere in Europe

Warming Precipitation

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Spruce forests in Norway are likely to expand

Today 2100

Climate change is likely to cause an increase in marine fish catch for Norway

- but a decrease in tropics and Southern Ocean

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Developed countries are causing the problem, but developing countries experience most health costs

Countries proportional to CO2 emissions (1950-2002)

Countries proportional to climate-sensitive health effects

Even more widespread and serious, according to the preponderance of evidence from scientists worldwide

…[is] dangerous global warming, caused by the buildup of greenhouse gases, especially carbon dioxide.

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www.lutheransrestoringcreation.org

“The earth is a planet of beauty and abundance; the earth system is wonderfully intricate and incredibly complex. But today living creatures, and the air, soil, and water that support them, face unprecedented threats. Many threats are global; most stem directly from human activity. Our current practices may so alter the living world that it will be unable to sustain life in the manner we know.” (ELCA, “Caring for Creation: Vision, Hope, and Justice,” 1993)

What can I do to minimize climate change?

We can change the future by implementing multiple solutions that already are available

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Weatherize your house: weather-strip, adequately insulate attic, and replace single-pane windows

with triple-pane windows

Next time, buy a more fuel-efficient car

20 mpg 30 mpg

50 mpg34 mpg

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Unfortunately, energy conservation is not a solution

- really just delays the outcome

Coal

Gas

67% of U.S. electricity is generated by burning coal or gas

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This can only happen through aggressive expansion of alternate energy sources

Solar Wind

To limit warming to 2o C, we need to reduce greenhouse gas emissions by 80% by 2050

Globally, we generate only 0.2% of our energy from wind,and only 0.1% from solar

Global wind potential is >40 times worldwide use

All 9 highest CO2-emitting countries could use wind alone

23x

183x

18x3x8x

8x3x

30x183x

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Wind power in Michigan could supply 12 times current statewide electricity demand

e.g. Luddington pumped storage plant

The “intermittency problem” can be solved easily

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More energy reaches Earth from the sun in 1 hour than humans on the entire planet use in 1 year!

Solar energy has even greater potential

Three main solar electricity technologies:

photovoltaicssolar tower parabolic trough

Global potential estimated at up to 100 times current use

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A small portion of the Sahara desert could supply all of the world’s electricity

A solar array 100 x 100 miles could provide all of US energy needs today

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Again, “intermittency problem” can be solved easily

- store excess heat during day, generate electricity at night

solar tower parabolic trough

Sooo… we’re not doing it now because the cost is much higher than electricity from coal, right?

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The true costs of wind and solar are already lower than coal-generated electricity

True cost per kilowatt hour of power

Coal: 26¢

Offshore wind: 3¢Onshore wind: 6¢Solar troughs: 11¢Solar towers: 20¢

Solar PV: 40¢

Educate others

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Encourage policymakers to make smarter choices

MI 6th District voters will have a clear choice

3.5o C Warming

2o C Warming

Low Moderate High

What would we gain by making these smarter choices?

Probability of species extinctions

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Worst case scenario:

< 0.01%0.3%