Climate change during the Quaternary period

The Quaternary Period

The Quaternary period spans from 2.6 million years ago to the present day. It is the most recent period in the Earth’s history.
This period is marked by a number of ice ages and warmer interglacial periods.

Ice Ages and Interglacial Periods

An ice age is a long period of reduction in the temperature of the Earth’s surface and atmosphere, resulting in the expansion of continental and polar ice sheets and alpine glaciers.
Interglacial periods are phases of warmer climate between ice ages. We are currently in an interglacial period known as the Holocene epoch, which began around 11,700 years ago.
Evidence of these climatic changes is visible within the sequence of rock types, ice cores, fossils, and ancient pollen.

Causes of Climate Change During the Quaternary Period

There are several natural factors that contributed to climate change during the Quaternary period.
Orbital Theory (Milankovitch Theory) suggests that changes in the Earth’s orbit around the sun, changes in the tilt of the Earth’s axis, and the precession or ‘wobble’ of the Earth on its axis can lead to an ice age.
Volcanic activity and changes in the concentration of atmospheric gases, such as carbon dioxide and methane, also influenced the climate in the Quaternary period.

Impact of Climate Change During the Quaternary Period

The climate changes during the Quaternary period have had dramatic effects on the planet.
During ice ages, large parts of the Earth’s surface were covered by ice sheets, altering landscapes via erosion and deposition.
These climatic changes also influenced the development and dispersal of humans and other species, leading to extinctions and population migrations.
Furthermore, during the ice ages, sea levels dropped due to the large quantity of water frozen in ice sheets, resulting in the exposure of land bridges such as the one between Britain and Europe. These were subsequently submerged during interglacial periods when the ice melted and sea levels rose.

Climate Change in the Recent Quaternary Period

Over the past 100,000 years, the Earth’s climate has become increasingly unstable with more frequent and larger temperature swings.
The last ice age ended around 11,700 years ago, and since then, the Earth’s climate has been relatively stable, allowing human civilisation to develop.
However, in the last 200 years, human activities have significantly influenced the Earth’s climate, leading to a rapid warming trend.