Jääajas

Jääajas is a Finnish term that translates to "Ice Age" in English. It refers to the geological periods of extensive glaciation in Earth's history. These periods are characterized by significant drops in global temperatures, leading to the formation of large ice sheets and glaciers that cover vast areas of the continents. The most recent Ice Age, known as the Quaternary glaciation, began approximately 2.6 million years ago and is characterized by cycles of glacial and interglacial periods. During glacial periods, ice sheets expand, lowering sea levels as water is locked up in ice. Interglacial periods are warmer, with ice sheets retreating and sea levels rising.

The study of Jääajas is crucial for understanding Earth's climate history, paleogeography, and the evolution of life. Evidence for past ice ages is found in geological formations such as moraines, erratics, glacial striations, and U-shaped valleys. Scientists use various methods, including ice core analysis, sediment core dating, and paleomagnetic data, to reconstruct the timing, extent, and impact of these icy epochs. The effects of past Jääajas continue to shape the Earth's landscape today, influencing topography, soil formation, and biodiversity. Understanding these past climatic shifts also provides valuable context for studying contemporary climate change.