Vital GEO Graphics

Anthropogenic Pressure on the Earth’s Climate System The last few decades have seen climate disruption unprecedented over the recent millennia. The trend towards global warming is virtually certain, with 11 of the 12 years to 2006 ranking among the 12 warmest years since 1850, the year when systematic temperature recording began. The Earth’s surface temperature has increased by about 0.74°C since 1906 and there is a strong con- sensus among scientists that the globally averaged net effect of human activities since 1750 has been one of warming. The heating up of the earth in the last few decades has been exceptionally rapid in comparison to the changes in climate during the past two millennia. The Earth’s climate has now entered a state that has no parallel in recent prehistory. The greatest direct human pressure on the climate system arises from the emission of greenhouse gas-

es, pre-eminent of which is CO 2 , mainly originating from burning fossil fuels. Since 1987 annual global emissions of CO 2 have risen by about one-third. However, the per capita emissions figures clearly illustrate large differences among regions.

D ownload G raphic 2

ved warming over the 20th century compared with climate model calculations

Temperature anomaly C

Temperature anomaly C

models using only natural forcings

Temperature anomaly C

1.5

1.5

1.5

Europe

Asia

North America

1.0

models using both natural and anthropogenic forcings

1.0

1.0

0.5

0.5

0.5

observations

0

0

0

1950

2000

1900

1950 2000 Temperature anomaly C

1950

1900

2000

1900

Temperature anomaly C

Temperature anomaly C

1.5

1.5

1.5

Australia

Latin America

Africa

1.0

1.0

1.0

0.5

0.5

0.5

0

0

0

1950

1950

1950

2000

1900

2000

1900

2000

1900

Temperature anomaly C

1.0 0.5 0 1.5

Global

Global – land

Global – ocean

1950

1950

1950

2000

2000

2000

1900

1900

1900

Source: IPCC 2007

11 CL IMAT E CHANGE