Slide 29:Thermal indicators: global air temperature
The mean global temperature has risen considerably in the past century (0.6°C ± 0.2°C) (IPCC, 2001).
The 1990s were the warmest decade ever recorded .
Furthermore, proxy records indicate that temperatures have not reached current levels for at least the past thousand years.
In fact, proxy records indicate that the last time global temperature reached levels like the current conditions were at the peak of the last interglacial period, 124 000 years ago.
Note that proxy records for recent history corroborate instrumental temperature assessments. This indicates the accuracy of proxy interpretation methods.
IPCC, 2001: Climate change 2001: the scientific basis. Contribution of Working Group I to the third assessment report of the Intergovernmental Panel on Climate Change. Cambridge University Press, 881 pp.