Global average surface temperature increased by about 0.6 degrees Centigrade over 20th century.

1990s warmest decade and 1998 warmest year in last 1000 years in Northern Hemisphere.

Over last 50 years night time minimum temperatures increased by about 0.2 degrees Centigrade per decade.

10 percent reduction in snow cover since late 1960's.

Reduction of about two weeks in annual duration of lake and river ice over 20th century
Widespread retreat of mountain glaciers during 20th century.

Northern Hemisphere spring and summer sea-ice extent decreased by 10-15% since 1950s.

40% decline in late summer Arctic sea-ice thickness in recent decades.

Global average sea level has increased by 10-20 cm during the 20th century.

0.5-1% per decade increase in Northern Hemisphere mid-latitude precipitation during 20th century.

2-4 percent increase in frequency of heavy precipitation events in Northern Hemisphere mid and high latitudes over latter half of 20th century.

Concentrations of greenhouse gases have continued to increase: CO2 by 31% since 1750; Methane by 151% since 1750; N2O by 17% since 1750.

Temperature and sea level are projected to rise under all scenarios

Land areas will warm more than the global average

Global average precipitation will increase over 21st century

More intense precipitation events very likely

Rate of warming likely unprecedented in at least last 10,000 years

Snow cover and sea-ice extent projected to decrease further

Global-average surface temperature projected to increase by 1.4-5.8 degrees Centigrade by 2100

Glaciers and icecaps projected to continue widespread retreat

Global mean sea-level projected to increase by 9 to 88 cm by 2100

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