The Little Ice Age (LIA) is a period of cooling occurring after a warmer period known as the Medieval climate optimum.

Climatologists and historians find it difficult to agree on either the start or end dates of this period.

Some confine the Little Ice Age to approximately the 16th century to the mid 19th century.

In the 13th century, pack ice had begun advancing southwards in the North Atlantic, as did glaciers in Greenland.

The three years of torrential rains beginning in 1315 usher in an era of unpredictable weather in Northern Europe which will not lift until the 19th century.

There is anecdotal evidence of expanding glaciers almost worldwide.

In contrast, a climate reconstruction based on glacial length shows no great variation from 1600 to 1850, though it shows strong retreat thereafter.

The Little Ice Age brings bitterly cold winters to many parts of the world, but is most thoroughly documented in Europe and North America.

There is evidence, however, that the Little Ice Age does affect the Southern Hemisphere.