The Effects of the Little Ice Age (c. 1300-1850)

  • The Little Ice Age was a period of wide-spread cooling that lasted from the end of the Medieval Warm Period early in the 14th century, until the present-day warming trend that started in the middle to late 19th century (graph below). During this time, in mountainous areas in Europe, Alaska, South America (Patagonia), and New Zealand, glaciers grew and expanded. Even though average annual temperatures in the Northern Hemisphere decreased by 0.6°C (1.1°F), certain areas experienced cold episodes for several decades with temperatures dropping by as much as 2°C (3.6°F) relative to thousand-year averages.

Timing and temperature variations during the Little Ice Age (from Encyclopaedia Britannica).

    • Cooling happened in phases, with an initial drop around 1300 and an even colder climate starting around 1560 (graph above).
    • Changes in climate did not happen uniformly around the globe. Cooling episodes in the Southern Hemisphere, such as in New Zealand and Patagonia, did not occur at the same time as cooling in the Northern Hemisphere. Some areas did not even experience cooling, such as eastern China. Europe experienced heavy rainfall while Africa and central and southern Asia experienced droughts. North America experienced both cooler temperatures and a drier period.
  • Evidence of cooling can be found in ice cores, tree rings, and other proxy paleoclimatic indicators. Additionally, there are written records from the time period and, beginning in 1659, direct meteorological measurements in Europe.
  • Climatologists believe that a combination of reduced solar output, changes in atmospheric circulation, and increased volcanism may have caused the Little Ice Age.
    • Decreased sunspot activity has been linked to decreased solar radiation, which in turn means that less energy is reaching Earth’s surface, providing less warmth and less energy for agriculture. Two periods of low sunspot activity (1450-1540 and 1645-1715) coincided with some of the coldest years of the Little Ice Age in Europe. 
    • The North Atlantic Oscillation is an atmospheric circulation pattern over the North Atlantic Ocean. In its positive phase, storms are centered over the United Kingdom and Northern Europe. In its negative phase, moist air is directed towards the Mediterranean and cold air is directed towards Northern Europe. Alternating phases of the North Atlantic Oscillation NAO may have contributed to the Little Ice Age and its variable effects in different places.
    • Volcanic eruptions can eject large amounts of volcanic ash into the atmosphere, which can block out sunlight and lower temperatures. There were several large volcanic eruptions during the Little Ice Age, including Laki in Iceland in 1783 and, in Indonesia, Lombok in 1257 and Mount Tambora in 1815.
  • Some recent research has pointed to a possible connection between the “Great Dying” — the genocide of Indigenous Peoples across the Americas via colonialism and disease — of the 16th century and a slight exacerbation of decreasing global surface air temperatures. The deaths of a vast majority of the roughly 60 million Indigenous Peoples in the Americas, many of which had cultivated land for thousands of years, meant that wild plants were allowed to grow rapidly across these vast territories. This increase in plant biomass relative to when the land had been cultivated created a dip in atmospheric carbon dioxide and lead to additional cooling.
    • This connection highlights the dramatic environmental changes that accompanied the violence of European colonization, helping to accentuate the effects of the profound brutality aimed at the many Indigenous Peoples of the Americas by European colonizers.
  • The climate of the Little Ice Age influenced many social, historical, and cultural events around the world during this time period.

References and Additional Resources