Here's a citation from the wikipedia article on the subject :
The main conclusions of the IPCC on global warming were the following:
The global average surface temperature has risen 0.6 ± 0.2 °C since the late 19th century, and 0.17 °C per decade in the last 30 years.
"*There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities*", in particular emissions of the greenhouse gases carbon dioxide and methane.
If greenhouse gas emissions continue the warming will also continue, with temperatures projected to increase by 1.4 °C to 5.8 °C between 1990 and 2100. Accompanying this temperature increase will be increases in some types of extreme weather and a projected sea level rise. On balance the impacts of global warming will be significantly negative, especially for larger values of warming.No scientific body of national or international standing has maintained a dissenting opinion