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A very long period, it could be millions of years, during which major parts of Earth are covered with ice because of a significant drop in temperature, is termed an ice age. Geologists say that the most recent was the Little Ice Age, which started in the 16th century in Europe and many regions across the world and reached its peak in 1850. |
An ice age is a period in which the earth’s climate is colder than normal, with ice sheets capping the poles and glaciers dominating higher altitudes. Within an ice age, there are varying pulses of colder and warmer climatic conditions, known as ‘glacials’ and ‘interglacials’. Even within the interglacials, ice continues to cover at least one of the poles. In contrast, outside an ice age temperatures are higher and more stable, and there is far less ice all around. The earth has thus far made it through at least five significant ice ages.
One glance at our icy poles and frozen peaks makes it clear that our current epoch (the Holocene, c. 12,000-present day) actually represents an interglacial within the ice age that spans the Quaternary geological period, which started around 2,6 million years ago and encompasses both the Pleistocene (c. 2,6 million years ago – c. 12,000 years ago) and the Holocene epochs. This entire period is characterised by cycles of ups and downs in ice sheet volumes and temperatures which can sometimes change as much as 15°C within a couple of decades. This rapidly overturning climate can have huge knock-on effects all around the world, altering vegetation and the types of animals that can survive in certain areas, and it helped shape human evolution, too.
Credit: World History Encyclopedia
Picture Credit : Google
