Write a one sentence overview on what we will learn today based on this picture.

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Write a one sentence overview on what we will learn today based on this picture.

Climate Change:Fitting the pieces together

Atmosphere

Ocean

Polar Ice

Human/natural influence

Ecosystem

Present day observations

Change in Temp

Past Data: How do we know?Data Collection!

Tree ring data Ice Core

Fossil Evidence Patterns and chemical comp in coral skeletons

Hadley Centre, 2003

Surface, balloon, & satellite temperatures agree

Temperature increases are nonuniform: higher mid-continent, highest of all in far North. (These are observations, not modeling results.)

J. Hansen et al., PNAS 103: 14288-293 (26 Sept 2006)

2001-2005 mean ∆Tavg above 1951-80 base, °C

Evaporation & precipitation are increasing

NCDC, 2000

Effect is not uniform; most places getting wetter, some getting drier.

GLACIERS ARE MELTING

Muir Glacier, Alaska, 1941-2004

NSIDC/WDC for Glaciology, Boulder, compiler. 2002, updated 2006. Online glacier photograph database. Boulder, CO: National Snow and Ice Data Center.

August 1941 August 2004

Coastal glaciers are retreating

The most startling evidence yet…

The melting of the Arctic

MELTING OF THE ARCTIC.

New predictions

Satellite observationsMean IPCC predictionMost likely change

(melt)IPCC range

Actual observed melting

it has melted nearly 80 YEARS ahead of when

scientists predicted

YEAR

% c

han

ge in

ice

cover

WEATHER IS BECOMING MORE EXTREME

MAJOR FLOODS PER DECADE

Australia fires spark calls for CLIMATE

ACTION“ ”- Washington Post, March 1, 2006

The trend has been upward everywhere.

Wildfires by continent & decade from 1950

Westerling et al., SCIENCE, 18 August 2006

Correlation of wildfire increases with temperature is clear

Running, Science, 18 August 2006

This works in part through soil moisture

Australia suffers worst drought in

1,000 years “ ”

- Guardian UK, Nov 7, 2008

SEA LEVELS ARE RISING

Three Year Average

Satellite Altimetry

Year

Sea L

evel C

han

ge (c

m)

1993-2003 ≈ 35 mm = 3.5 mm/yr; compare 1910-1990 = 1.5±0.5 mm/yr.

Sea-level is risingmm

ACIA, 2004

Further evidence of changing climateObservations Show…

Evaporation & rainfall are increasing;

Coastal glaciers are retreating;

Mountain glaciers are disappearing;

Permafrost is thawing;

Sea ice is shrinking;

Greenland is melting;

Sea level is rising;

Species are moving.

Why should we care?

Temp expected to increase by 2-13o F by 2100

Oceans absorb more CO2

Some expected changes… Warmer temps mean mosquitoes, ticks and rodents expand their range

Less snow—people who depend on snow-fed reservoirs for water

5-20% inc. in crop yield, but more prone to failure with increase temp and decrease in precipitation

OCEANS ARE ACIDIFYING

FORESTS ARE THREATENED

Coral reefs are bleaching

threatens the survival of

SMALL ISLANDS

Already, the president of the Maldives has created an investment fund from tourism earnings so the nation can buy a new homeland in Sri Lanka and India, for its citizens in case of massive flooding.

Sea-level rise projections : a few inches to a few feet

•2 ft: U.S. would lose 10,000 square miles•3 ft: Would inundate Miami•Affects erosion, loss of wetlands, freshwater supplies•Half of the world’s population lives along coasts

What changes climate?

Changes in:Sun’s outputEarth’s orbitDrifting continentsVolcanic eruptionsGreenhouse gases

Earth’s Atmosphere

CO2 is found in troposphere.

THE GREENHOUSE EFFECT

“Greenhouse effect” Increasing greenhouse gases trap more heat

Greenhouse gases

Nitrous oxide

Water

Carbon dioxideMethane

Sulfur hexafluoride

Atmospheric CO2 Levels

http://climate.nasa.gov/key_indicators

CO2 CONCENTRATIONS ARE OFF THE CHARTS

CO2 in PPM

TEMPERATURE

Years

Part

s p

er

Million

C

O2

TODAY: 387ppm

550ppm? More?

EARLY 1900S

LAST ICE AGE

Where we’ll be mid-century if we keep this up

390ppm CO2

today:

Raising by 2ppm/year

The Industrial Revolution changed our energy consumption

Combustion Reactions produce CO2

Combustion Reaction:CH4 + O2 CO2 + H2O

(Fossil fuel)

CO2 IN THE ATMOSPHERE

WE’RE HERE: 387

WE NEED TO BE HERE: 350

PA

RTS

PER

MIL

LIO

N C

O2

YEAR

?HOW DO WE GET TO

Can we fix it? Yes we

can!!

AND IMPLEMENTING AND IMPLEMENTING

A A THOUSAND THOUSAND

DIFFERENT DIFFERENT SOLUTIONSSOLUTIONS

IT MEANS PLANTING TREESINSTEAD OF CLEAR-CUTTING

RAINFORESTS

IT MEANS PUTTING UP WIND TURBINESINSTEAD OF COAL PLANTS

PA

RTS

PER

MIL

LIO

N C

O2

YEAR

Phase-out of coal by 2030

Improved forestry and soil

Reduced oil/gas use

GETTING TO 350

Spread the word…

http://www.youtube.com/watch?v=zORv8wwiadQ

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