Studies Say--Tentatively--That Greenhouse Warming Is Here

摘要

Searing hot summers and hearings on Capitol Hill seem to bring out claims that green-house watming has arrived, but published studies have mostly been assiduously ambiva-lenton the question. For more than a decade, researchers have been debating whether the half-degree of global warming observed so far this century is the signature of humanmade gteenhouse gases.or some self-correcting climate variation utterly beyond human control. Now two independent studies of the climate record have incriminated the greenhouse effect in global warming, although they fall short of convicting it.