Jääaikojen

Jääaikojen is a Finnish term that translates to "Ice Ages" or "Ice Periods." It refers to recurring periods of prolonged glaciation in Earth's history, during which large parts of the planet's surface were covered by ice sheets and glaciers. These periods are characterized by a significant drop in global temperatures, leading to the expansion of polar ice caps and the formation of continental glaciers.

The most recent major glacial period, often referred to as the Quaternary glaciation, began about 2.6 million years ago and is still ongoing, though we are currently in a warmer interglacial period within this larger epoch. During the peak of glacial periods, ice sheets extended across much of North America, Europe, and Asia. These ice sheets dramatically shaped the Earth's landscape, carving out valleys, creating fjords, and depositing vast amounts of sediment.

The causes of ice ages are complex and are thought to involve a combination of factors. These include variations in Earth's orbit (Milankovitch cycles), changes in atmospheric composition, volcanic activity, and the configuration of continents. The study of ice ages is crucial for understanding past climate changes, predicting future climate trends, and comprehending the geological history of our planet. Evidence for past ice ages is found in geological formations such as moraines, erratics, and striations on rocks, as well as in ice cores that preserve atmospheric data from millennia past.