In the Medieval Warm Period (MWP), from the end of the ninth century to the beginning of the 14th, the Northern Hemisphere was warmer than at any time in the past 8,000 years — there were vineyards in northern England [leading] to Europe’s “first sustained population increase since the fall of the Roman Empire.” The need for land on which to grow cereals drove deforestation. The MWP population explosion gave rise to towns, textile manufacturing and new wealthy classes.But then came
the severe winters of 1309-1312, when polar bears could walk from Greenland to Iceland on pack ice. In 1315 there was rain for perhaps 155 consecutive days, washing away topsoil. Upwards of half the arable land in much of Europe was gone; cannibalism arrived as parents ate children. Corpses hanging from gallows were devoured.Will also documents another horrendous turn of the climate change cycle: the Little Ice Age, between the 1640s and the 1690s,
caused, among other horrific things, “stunting” that [Ohio State history professor Geoffrey] Parker says, “reduced the average height of those born in 1675, the ‘year without a summer,’ or during the years of cold and famine in the early 1690s, to only 63 inches: the lowest ever recorded.” The flight from abandoned farms to cities produced the “urban graveyard effect,” crises of disease, nutrition, water, sanitation, housing, fire, crime, abortion, infanticide, marriages forgone and suicide. Given the ubiquity of desperation, it is not surprising that more wars took place during the 17th-century crisis “than in any other era before the Second World War.”Will is telling us big climate changes in the past had nothing to do with man-made global warming produced by increased CO2 emissions, and wants that evidence to be part of the current climate change debate. Today, though CO2 emissions have increased yearly, global temperatures have plateaued for the past decade and a half. It appears that old computer models that link CO2 to temperature increases are increasingly out of date.
But doesn’t Will’s version of history tell us that climate change produces disasters? So it’d be wonderful if we really could do something about the weather after all.