of Global Warming Observations
and duration of warming in 20th century is larger than any other
time in last 1000 years.
- The 1990s are likely to have been warmest decade of the
millennium in the Northern Hemisphere.
- 1998 is likely to have been the warmest year.
- Note: A few areas of the globe have not warmed in recent
decades: some areas of Southern Hemisphere and parts of
- Total atmospheric water vapor has likely increased several
percent per decade over many regions in NH
- some subtropical regions are experiencing more
land precipitation has increased in the middle and high latitudes
of the Northern Hemisphere.
cloud cover by about 2% since the beginning of the 20th century
over the Northern Hemisphere.
snow cover and sea-ice amounts in NH.
significant trends in Antarctic sea-ice are apparent.
mean sea-level rise during 20th century has been observed to be
1.0-2.0 mm per year.
in heavy and extreme precipitation events in regions where total
precipitation has increased.
from 4th IPCC Assessment