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What causes global What causes global warming? You do,silly!warming? You do,silly!

Kevin CumminsKevin Cummins

Sierra Club VolunteerSierra Club Volunteer

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Increases in carbon dioxide cause Increases in carbon dioxide cause the earth to get warmerthe earth to get warmer

Greenhouse gases such as carbon dioxide (CO2) (plus Greenhouse gases such as carbon dioxide (CO2) (plus other gases like methane) in the atmosphere absorb other gases like methane) in the atmosphere absorb heat radiating from the earth. heat radiating from the earth.

This trapped heat increases the evaporation of water from This trapped heat increases the evaporation of water from the oceans into the air to cause a greater increase in the oceans into the air to cause a greater increase in warming of the atmosphere. CO2 has a forcing effect warming of the atmosphere. CO2 has a forcing effect on climate. on climate.

The combined effect of water vapor, carbon dioxide and The combined effect of water vapor, carbon dioxide and methane controls the temperature of the earth.methane controls the temperature of the earth.

33Source: OSTP

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Carbon dioxide levels in the Carbon dioxide levels in the atmosphere are increasingatmosphere are increasing

Carbon dioxide is produced from burning Carbon dioxide is produced from burning wood, coal, gas, etc.wood, coal, gas, etc.

The amount in the atmosphere has risen The amount in the atmosphere has risen from 280 ppm (100+ years ago) to 370 from 280 ppm (100+ years ago) to 370 ppm today.ppm today.

This increase in carbon dioxide is the This increase in carbon dioxide is the atmosphere is increasing the heat being atmosphere is increasing the heat being absorbed from the earth.absorbed from the earth.

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CO2,CH4 and estimated global temperature (Antarctic ΔT/2 in ice core era)0 = 1880-1899 mean.

Source: Hansen, Clim. Change, 68, 269, 2005.

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Today’s atmosphere blanket is too Today’s atmosphere blanket is too thick!thick!

The increase in CO2 in the atmosphere The increase in CO2 in the atmosphere traps more heat and causes more water traps more heat and causes more water vapor to evaporate into the atmosphere.vapor to evaporate into the atmosphere.

Our new blanket around the world is Our new blanket around the world is simply making the earth too warm!simply making the earth too warm!

We need a thinner blanket for our earth!We need a thinner blanket for our earth!

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What can happen if we don’t What can happen if we don’t produce less CO2 ?produce less CO2 ?

Temperatures will get warmer. Temperatures will get warmer.

Glaciers will melt, ice sheets in Artic will Glaciers will melt, ice sheets in Artic will melt (Polar Bears hunt on ice sheets)melt (Polar Bears hunt on ice sheets)

Sea levels will rise. Utah will be on Pacific Sea levels will rise. Utah will be on Pacific Coast…. NOT!Coast…. NOT!

More droughts in dry areas and more rain More droughts in dry areas and more rain and snow in wet areas. and snow in wet areas.

More violent weather around the world.More violent weather around the world.

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If nothing is done to slow If nothing is done to slow greenhouse gas emissions. . .greenhouse gas emissions. . .

• COCO22 concentrations will likely concentrations will likely

be more than 700 ppm by 2100be more than 700 ppm by 2100

• Global average temperatures Global average temperatures projected to increase between projected to increase between 2.5 - 10.4°F2.5 - 10.4°F

2100

Source: OSTP

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Melt descending into a moulin, a vertical shaftcarrying water to ice sheet base.

Source: Roger Braithwaite, University of Manchester (UK)

Surface Melt on Greenland

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How can we stop the earth’s How can we stop the earth’s “blanket” from getting us to warm?“blanket” from getting us to warm?We must start putting less carbon dioxide into We must start putting less carbon dioxide into the air.the air.Most the CO2 in the air will be around for 100 Most the CO2 in the air will be around for 100 years.years.We need to burn less gasoline in our cars.We need to burn less gasoline in our cars.Burn less coal (or burn it cleaner) for our Burn less coal (or burn it cleaner) for our electricity.electricity.Use less gas to heat our homes.Use less gas to heat our homes.Use less gas and electricity in our factories and Use less gas and electricity in our factories and on our farms.on our farms.

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What can we use for energy to What can we use for energy to replace carbon based fuels? replace carbon based fuels?

SolarSolar

BiofuelsBiofuels

WindWind

Nuclear Power (may be necessary Nuclear Power (may be necessary whether we like it or not!)whether we like it or not!)

GeothermalGeothermal

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We can also use less fuel We can also use less fuel

Higher mileage carsHigher mileage cars

Live and work closer to homeLive and work closer to home

Walk, ride bikesWalk, ride bikes

Better insulated homesBetter insulated homes

Use more efficient lights (fluorescent/LED)Use more efficient lights (fluorescent/LED)

More efficient factoriesMore efficient factories

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What can you do about?What can you do about?

Discuss it with your parents, friends and Discuss it with your parents, friends and relativesrelatives

Conserve more yourself. Conserve more yourself.

Write your elected officialsWrite your elected officials

Go to college and find new and better Go to college and find new and better solutions for the future.solutions for the future.

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So what’s the bad news/good news So what’s the bad news/good news if we don’t act soon?if we don’t act soon?

Bad news: We could lose control of the Bad news: We could lose control of the temperature rise of the earth. CO2 and methane temperature rise of the earth. CO2 and methane from warm tundra and oceans could be released from warm tundra and oceans could be released to atmosphere. This could be beyond our to atmosphere. This could be beyond our control. A “run away condition”control. A “run away condition”

Good news: Schools would close. NOT! Good news: Schools would close. NOT!

Good news: Maybe global engineering could Good news: Maybe global engineering could save us! (reflectors in space, dust in space) save us! (reflectors in space, dust in space)

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What can the future hold for you What can the future hold for you children?children?

More community spirit- we all must work More community spirit- we all must work together to solve the global warming together to solve the global warming problemproblem

A safer world with fewer enemies. GW A safer world with fewer enemies. GW can only be solved with world cooperation.can only be solved with world cooperation.

Less proverty in the world. Solving the Less proverty in the world. Solving the world’s GW problem cooperatively will world’s GW problem cooperatively will require that proverty be reduced.require that proverty be reduced.

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As my high school teacher used to As my high school teacher used to say:say:

““Don’t be a carbuncle on the butt of Don’t be a carbuncle on the butt of society!”society!”

Get out there and make the world a better Get out there and make the world a better place to live!place to live!

And also don’t forget to take care of the And also don’t forget to take care of the elderly along the way (Myself included)elderly along the way (Myself included)

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ReferencesReferences

Intergovernmental Panel on Climate Change, www.ipcc.ch/Intergovernmental Panel on Climate Change, www.ipcc.ch/““The New Scientist.com”, A Special Report on Climate Change, The New Scientist.com”, A Special Report on Climate Change, http://www.newscientist.com/channel/earth/climate-change.http://www.newscientist.com/channel/earth/climate-change.““Defusing the Global Warming Time Bomb” by James Hansen, Defusing the Global Warming Time Bomb” by James Hansen, Scientific AmericanScientific American, 290, no. 3, March 2004, pp. 68-77. (available , 290, no. 3, March 2004, pp. 68-77. (available for download at http://www.columbia.edu/~jeh1/)for download at http://www.columbia.edu/~jeh1/)EPA global warming Website: EPA global warming Website: http://yosemite.epa.gov/oar/globalwarming.nsf/content/index.htmlhttp://yosemite.epa.gov/oar/globalwarming.nsf/content/index.html “ “Climate Change and Utah”, USEPA, EPA 236-F-98-007z. Sept. Climate Change and Utah”, USEPA, EPA 236-F-98-007z. Sept. 1998, available at : 1998, available at : http://yosemite.epa.gov/oar/globalwarming.nsf/content/us-utah.htmlhttp://yosemite.epa.gov/oar/globalwarming.nsf/content/us-utah.htmlFor young children (story book style):For young children (story book style):http://www.unep.org/PDF/TORE.pdfhttp://www.unep.org/PDF/TORE.pdf

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DisclaimerDisclaimer

The preceding is my opinion and does not The preceding is my opinion and does not necessarily reflect the opinion of the Sierra necessarily reflect the opinion of the Sierra Club. Club.