0°

59°

Lonnie G. Thompson

800,000 700,000 600,000 500,000 400,000 300,000 200,000 100,000 0

Age (years BP)

CO

2 C

on

cen

tratio

n

Source: National Climatic Data Center/NOAA

300

180

200

220

240

260

280

CO

2 (

pp

m)

300

180

200

220

240

260

280

CO

2 (

pp

m)

Tem

p. in

F°

800,000 700,000 600,000 500,000 400,000 300,000 200,000 100,000 0

Source: National Climatic Data Center/NOAA

Age (years BP)

CO

2 C

on

cen

tratio

n

CO

2 (

pp

m)

400

320

340

360

380

300

180

200

220

240

260

280

Tem

p. in

F°

800,000 700,000 600,000 500,000 400,000 300,000 200,000 100,000 0

Source: National Climatic Data Center/NOAA

Age (years BP)

2008 CO2 Concentration: 387

CO

2 C

on

cen

tratio

n

400

CO

2 C

on

cen

tratio

nC

O2 (

pp

m)

320

340

360

380

300

180

200

220

240

260

280

Tem

p. in

F°

800,000 700,000 600,000 500,000 400,000 300,000 200,000 100,000 0

Age (years BP)

2008 CO2 Concentration: 387

Source: National Climatic Data Center/NOAA

350

1980

2007

Photo: Katherine Cherewyk

“Warming of the climate system is unequivocal.”

Intergovernmental Panel on Climate Change (IPCC) AR4, 2007

unequivocal: beyond doubt

Photo: NOAAPhoto: NOAA

Hurricane KatrinaHurricane KatrinaAugust 2005August 2005

HaitiHaitiSeptember 2008September 2008

Number of Major Flood Events by Continent and Decade

# o

f M

ajo

r Flo

od

s

AmericasAmericas

Source: Millennium Ecosystem Assessment

1950–1959 1960–1969 1970–1979 1980–1989 1990–2000

Photo: AP/Ajit Solanki

Ahmadabad, IndiaAhmadabad, IndiaMay 2006May 2006

AustraliaAustraliaFebruary 2009February 2009

Number of Major Wild Fires#

of

Majo

r W

ild

fire

s

1950–1959 1960–1969 1970–1979 1980–1989 1990–2000

Source: Millennium Ecosystem Assessment