COVER STORY - Climate Change - How climate change could upend the Inland Northwest
Henning, who teaches global warming ethics, says Americans would need to cut between 60 percent and 80 percent of greenhouse gases to stave off catastrophe (species going extinct, global populations being displaced).TIME Magazine Archive Article -- Another Ice Age? -- Jun. 24, 1974
Several factors have been discarded as plausible theories, according to [Gonzaga University Associate Professor Brian Henning]. The changes can’t be coming from the sun, because given its current activity, we’d be getting cooler. And it can’t be from the planetary cycles that cause ice ages and warming periods, because we’re still 50,000 years away from another ice age, he says.
when meteorologists take an average of temperatures around the globe they find that the atmosphere has been growing gradually cooler for the past three decades. The trend shows no indication of reversing. Climatological Cassandras are becoming increasingly apprehensive, for the weather aberrations they are studying may be the harbinger of another ice age.
Telltale signs are everywhere —from the unexpected persistence and thickness of pack ice in the waters around Iceland to the southward migration of a warmth-loving creature like the armadillo from the Midwest.Since the 1940s the mean global temperature has dropped about 2.7° F. Although that figure is at best an estimate, it is supported by other convincing data. When Climatologist George J. Kukla of Columbia University's Lamont-Doherty Geological Observatory and his wife Helena analyzed satellite weather data for the Northern Hemisphere, they found that the area of the ice and snow cover had suddenly increased by 12% in 1971 and the increase has persisted ever since. Areas of Baffin Island in the Canadian Arctic, for example, were once totally free of any snow in summer; now they are covered year round.
Scientists have found other indications of global cooling. For one thing there has been a noticeable expansion of the great belt of dry, high-altitude polar winds —the so-called circumpolar vortex—that sweep from west to east around the top and bottom of the world. Indeed it is the widening of this cap of cold air that is the immediate cause of Africa's drought.