by: Peter Ferrara
Around 1250 A.D., historical records show, ice packs began showing up farther south in the North Atlantic. Glaciers also began expanding on Greenland, soon to threaten Norse settlements on the island. From 1275 to 1300 A.D., glaciers began expanding more broadly,
according to radiocarbon dating of plants killed by the glacier growth. The period known today as the Little Ice Age was just starting to poke through.
Summers began cooling in Northern Europe after 1300 A.D., negatively impacting growing seasons, as reflected in the Great Famine of 1315 to 1317. Expanding glaciers and ice cover spreading across Greenland began driving the Norse settlers out. The last, surviving, written records of the Norse Greenland settlements, which had persisted for centuries, concern a marriage in 1408 A.D. in the church of Hvalsey, today the best preserved Norse ruin.
Colder winters began regularly freezing rivers and canals in Great Britain, the Netherlands and Northern France, with both the Thames in London and the Seine in Paris frozen solid annually. The first River Thames Frost Fair was held in 1607. In 1607-1608, early European settlers in North America reported ice persisting on Lake Superior until June. In January, 1658, a Swedish army marched across the ice to invade Copenhagen. By the end of the 17th century, famines had spread from northern France, across Norway and Sweden, to Finland and Estonia.
Reflecting its global scope, evidence of the Little Ice Age appears in the Southern Hemisphere as well. Sediment cores from Lake Malawi in southern Africa show colder weather from 1570 to 1820. A 3,000 year temperature reconstruction based on varying rates of stalagmite growth in a cave in South Africa also indicates a colder period from 1500 to 1800. A 1997 study comparing West Antarctic ice cores with the results of the Greenland Ice Sheet Project Two (GISP2) indicate a global Little Ice Age affecting the two ice sheets in tandem.
The Siple Dome, an ice dome roughly 100 km long and 100 km wide, about 100 km east of the Siple Coast of Antartica, also reflects effects of the Little Ice Age synchronously with the GISP2 record, as do sediment cores from the Bransfield Basin of the Antarctic Peninsula. Oxygen/isotope analysis from the Pacific Islands indicates a 1.5 degree Celsius temperature decline between 1270 and 1475 A.D.
The Franz Josef glacier on the west side of the Southern Alps of New Zealand advanced sharply during the period of the Little Ice Age, actually invading a rain forest at its maximum extent in the early 1700s. The Mueller glacier on the east side of New Zealand’s Southern Alps expanded to its maximum extent at roughly the same time.
Ice cores from the Andeas mountains in South America show a colder period from 1600 to 1800. Tree ring data from Patagonia in South America show cold periods from 1270 to 1380 and from 1520 to 1670. Spanish explorers noted the expansion of the San Rafael Glacier in Chile from 1675 to 1766, which continued into the 19th century.
The height of the Little Ice Age is generally dated as 1650 to 1850 A.D. The American Revolutionary Army under General George Washington shivered at Valley Forge in the winter of 1777-78, and New York harbor was frozen in the winter of 1780. Historic snowstorms struck Lisbon, Portugal in 1665, 1744 and 1886. Glaciers in Glacier National Park in Montana advanced until the late 18th or early 19th centuries. The last River Thames Frost Fair was held in 1814. The Little Ice Age phased out during the middle to late 19th century.