World experts warn of climate-change smoking gun
Human-caused global warming is visible in the air, water and melting ice and destined to get much worse in the future, an authoritative world report will warn.
“The smoking gun is definitely lying on the table as we speak,” said top US climate scientist Jerry Mahlman, who reviewed all 1,600 pages of the first segment of a giant four-part report. “The evidence … is compelling.”