Europe's climate history has been characterized by alternating periods of relative warmth and relative cold. The most famous result of this alternation in temperature was the growing, then shrinking, of large masses of ice.

The climate changes were due to a combination of factors. Neither the orbit of the earth around the sun, nor the manner in which the earth rotates on its axis, is constant. The tilt of the earth's axis also varies slightly, through a cycle that lasts 41,000 years. All this movement means that the amount of sunshine that falls on a large portion of the earth, Western Europe in our case, is not constant. This causes ice ages, which occur about every 100,000 years. In recent history, four ice ages have occurred. For the Netherlands, however (including Wieringen), only the last two are of interest. In addition, within each ice age, there have been many fluctuations in the average temperature.

The second most recent ice age is named the Saalian and it occurred from 200,000 until 130,000 years ago. In the coldest period of the Saalian, a large part of Europe, including about half of the Netherlands, was covered in ice. The glaciers brought along all kinds of stone debris from Scandinavia (for example, the stray boulders which are a frequent site in Wieringen). The glaciers are even responsible for the rolling landscape - the hills of Wieringen (and Texel, Gaasterland, and a few other places in the Netherlands) are push moraines, caused by the enormous force of advancing glaciers. These geographical features, created during the Saalian, are known collectively as the Drentian Formation.

70,000 years later, Europe entered a warm period, called an "interglacial". The interglacial that began 130,000 years ago  lasted for 30,000 years, and was called the Eemian. The area around the North Sea slowly became tropical in climate, and, due to the rising sea level, most of Western Europe disappeared under water. Interglacials such as the Eemian are the reason we find fossilized fish and shells in hills that are currently hundreds of kilometers from the sea. There are even fossil coral formations that have been found in the Wadden Sea!

The last ice age is named the Weichselian, and it lasted from 100,000 to 10,000 years ago. During this time, the Neanderthals and our own ancestors both roamed together through the tundra plains that covered the Netherlands and the dry North Sea basin. This time, the glaciers didn't come as far as the Netherlands, but they definitely had an influence on the climate. There is no reason to believe that the Weichselian was the last ice age, even if there were no greenhouse effect. Strictly speaking, we are currently in an interglacial (called the Holocene) and have been for 10,000 years. It is not clear whether we are already at the peak of the interglacial (and that from now on it will slowly get colder again) or if the coming 10,000 years will become warmer. The Holocene has already gone through several colder and warmer periods. The period from ca. 700 to ca.1300 was relatively warm, and the period from ca. 1500 to ca. 1700 has been called the "little Ice age". Such climate changes appear to have had a great influence on the of passage of world history. The general climate trend over the last 10,000 years has been, however, an increase in average temperature.
 
 

Last updated: 13-8-2000