This article discusses scientist James Hansen’s predictions on climate change, back in 1988 through today.
On June 23, 1988—a blisteringly hot day in Washington, D.C.—James Hansen told a Senate committee that “the greenhouse effect has been detected and is changing our climate now.” At the time, Hansen was the head of nasa’s Goddard Institute for Space Studies, and though his testimony was certainly not the first official warning about the “greenhouse effect”—a report to President Lyndon Johnson, in 1965, predicted “measurable and perhaps marked changes in climate” in the decades to follow—it was the first to receive national news coverage. The Times ran the story at the top of the front page, with a graph showing a long-term rise in average global temperatures.
This week marks the thirtieth anniversary of Hansen’s testimony, and it would be hard to think of a more lugubrious milestone. In the intervening three decades, nearly half of the Arctic ice cap has melted away, the oceans have acidified, much of the American West has burned, lower Manhattan, South Florida, Houston, and New Orleans have flooded, and average temperatures have continued to climb. Just last week, a team of scientists reported in Naturethat the rate of melt off Antarctica has tripled in the past decade; as the Washington Post put it, “If that continues, we are in serious trouble.” (Were the Antarctic ice to melt away entirely, global sea levels would rise by two hundred feet; if just the more vulnerable West Antarctic Ice Sheet melted, sea levels would rise by about ten feet.) Also last week, scientists reported that most of Africa’s oldest baobab trees have died, probably because of climate change, and last month researchers showed that rising CO2 levels were reducing the nutrient content of rice, which is probably the single most important food source for people. Yet Washington continues to ignore the problem, or, worse still, to actively impede efforts to address it. How can this be?