vikingpower writes "The Little Ice Age, lasting from the end of the Middle Age into the 17th century, may very likely have been caused by the combined effects of four major volcanic eruptions and increased sunlight reflection by increasing sea ice, the so-called Albedo effect. ... The University of Boulder has a press release with maps and photographs. Bette Otto-Bliesner, one of the scientists behind the 'volcano + sea ice' thesis, fields an earnest warning against drawing conclusions too quickly from this research: 'I think people might look at the Little Ice Age and think that all we need to save us from rising temperatures are some volcanic eruptions or the geo-engineering equivalent [...] But when you see what happened when global temperatures dropped by just one degree and you look at current predictions of six or seven degree increases for the future, you realize how precarious things are for life as we know it.'"

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