Instrumental mean global temperatures 1880–2008 relative to 1961–1990. The image shows the instrumental record of global average temperatures compiled by NASA Goddard Institute of Space Science following the methodology outlined by Hansen et al (2006) “Global temperature change” Proc Natl Acad Sci 103: 14288–14293

Above picture source: http://commons.wikimedia.org/wiki/File:Instrumental_Temperature_Record.png accessed May 2009.This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article “Instrumental Global Circulation”. Cited from Andrew Glikson in "The Science of Climate Change" at this website below button "Atmosphere Evolution" in the info toolbox on the startpage.

For an excellent pedagogic Australian compilation of temperature change and scenarios click here

Observed regional temperature differences in global warming are already very pronounced.

As is shown below the global warming is spread extremely heterogenous regionally according to Hadley Metoffice , Exeter, UK.  This is interrelated to the fact that different soil types has very different physical properties. As is shown below the most heated region is in the polar area regions of the planet and especially in Siberia, which is extremely unhappy. This is the region of the huge amounts of "coldstored" methane hydrates. The contained permafrost in now quickly thawing permafrost peat areas due to the 3,7 °C warmer climate in Siberia may be developed inte a "methane bomb" for the planet says Dr Katey Walter who has spent several years in the most heated region to measure the accelerated leaking of methane into the atmosphere.

http://dotearth.blogs.nytimes.com/tag/hadley-center/

Hadley Institute, Exeter, UK says therefore in October 2008 that the total global C outlets of fossil C must decrease  3 % annually. This must get started in 2010, if the world should get a fair chance of  levelling the global warming by counterbalancing it in some way and thereby never pass the UN IPCC goal of avoiding + 2°C. If we override the + 2°C level evidence is now accumulating saying that then will roll up a cascade of physical variables mankind can never take control over. This will end up within 100 - 300 years  in the worst global heat shock during 450 million years according to professor Peter Cox, BBC program on "Global Dimming" in 2005.

As a pedagogically visualised example global temperatures during 2008 are summerized  by NASA here

One of the best pedagogic "clima change" survey articles we have seen is clickable below by the generous permission from the author:

     Andrew_Glikson_articles\THE SCIENCE OF CLIMATE CHANGE_ AUGUST 2009.pdf