Changes

[[Image:Rogerrevelle.jpg|thumb|right|200px|[[Roger Revelle]]]]

[[Image:Rogerrevelle.jpg|thumb|right|200px|[[Roger Revelle]]]]

'''Global warming''' is the increase of temperature since 1880. This increase in temperature is mainly caused by the increases in [[carbon dioxide]] and other [[greenhouse gas]]es.<ref>http://www.pnas.org/cgi/reprint/104/10/3713 Solar influence on climate during the past millennium: Results from transient simulations with the NCAR Climate System Model</ref> During the last century near surface tempertures rose about 0.8 K.<ref>[http://data.giss.nasa.gov/gistemp/2005/ GISS Surface Temperature Analysis 2005]</ref> The possibility of adverse consequences (especially: sea level rise, retreating of glaciers and water scarity) has become a major concern for environmentalists and some scientists.

'''Global warming''' is the increase of temperature since 1880. This increase in temperature is mainly caused by the increases in [[carbon dioxide]] and other [[greenhouse gas]]es.<ref>[http://www.pnas.org/cgi/reprint/104/10/3713 Solar influence on climate during the past millennium: Results from transient simulations with the NCAR Climate System Model (pdf)]</ref> During the last century near surface tempertures rose about 0.8 K.<ref>[http://data.giss.nasa.gov/gistemp/2005/ GISS Surface Temperature Analysis 2005]</ref> The possibility of adverse consequences (especially: sea level rise, retreating of glaciers and water scarity) has become a major concern for environmentalists and some scientists.

According to geologists, the Earth has experience numerous [[ice age]]s during which the temperature dropped so far that [[glacier]]s could cover [[North America]] and [[Europe]].  

According to geologists, the Earth has experience numerous [[ice age]]s during which the temperature dropped so far that [[glacier]]s could cover [[North America]] and [[Europe]].