Climate Change - The last 2,000 years of global temperatures

Average global temperature is now higher than it has been for a long time.


Graph by Klaus Bitterman.

Green dots show the 30-year average of the PAGES 2k reconstruction. 

The red curve shows the global mean temperature, based on HadCRUT4 data from 1850 onwards. 

In blue is the original "hockey stick" from a paper by Mann, Bradley and Hughes (1999) with its uncertainty range (light blue). 

The green dots are calculated using data from many places around the world, using information from a range of temperature proxies, such as documents, ice, lakes, pollen, tree rings, corals, seabeds and speleothems.


PAGES is the Past Global Changes programme launched in 1991. 

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