A panel of the [[United Nations]] is "90% sure" that most [[global warming]] since about 1950 has been caused by human beings,<ref>[http://physicsworld.com/cws/article/news/26979 Mankind to blame for global warming, says IPCC]</ref> but most scientists are skeptical about this view.{{fact}} | A panel of the [[United Nations]] is "90% sure" that most [[global warming]] since about 1950 has been caused by human beings,<ref>[http://physicsworld.com/cws/article/news/26979 Mankind to blame for global warming, says IPCC]</ref> but most scientists are skeptical about this view.{{fact}} |