Tree ring data from Patagonia in South America show cold periods from 1270 to 1380 and from 1520 to 1670.

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In fact, a recent study conducted by German researchers using tree ring data reveals that 2, 000 years ago Romans wore cool togas with good reason.

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In North America, Laki has been blamed for the starvation of Inuit populations from severe cold in northwestern Alaska, based on Inuit oral history as well as tree-ring density data investigated by Gordon Jacoby and others, who estimated that conditions were about 4 degrees Celsius colder than the mean.

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