This story from the other day, about a new island formed off of Greenland, made me think of the changes Greenland's climate underwent during the Medieval Warming Period and the subsequent Little Ice Age. This site has a nice overview. Interesting that falling temperatures were more difficult than rising ones...
The cooler climate during the LIA had a huge impact on the health of Europeans. As mentioned earlier, dearth and famine killed millions and poor nutrition decreased the stature of the Vikings in Greenland and Iceland.
Cool, wet summers led to outbreaks of an illness called St. Anthony's Fire. Whole villages would suffer convulsions, hallucinations, gangrenous rotting of the extremities, and even death. Grain, if stored in cool, damp conditions, may develop a fungus known as ergot blight and also may ferment just enough to produce a drug similar to LSD. (In fact, some historians claim that the Salem, Massachusetts witch hysteria was the result of ergot blight.)
Malnutrition led to a weakened immunity to a variety of illnesses. In England, malnutrition aggravated an influenza epidemic of 1557-8 in which whole families died. In fact, during most of the 1550's deaths outnumbered births (Lamb, 1995.) The Black Death (Bubonic Plague) was hastened by malnutrition all over Europe.
Shakespeare took note of the spread of malaria in England; Cromwell died from it.Posted by Ideofact at April 26, 2007 10:31 PM