jäätymisvaikutus

Jäätymisvaikutus, also known as the ice-albedo feedback, is a significant process in climate science. It describes how changes in ice cover influence global temperatures. Ice, particularly snow and glaciers, has a high albedo, meaning it reflects a large portion of incoming solar radiation back into space. This reflectivity helps to keep the Earth's surface cool.

When the Earth's temperature rises, ice begins to melt. As ice cover diminishes, the darker surfaces beneath, such as open water or land, are exposed. These darker surfaces have a lower albedo and absorb more solar radiation. This increased absorption of heat leads to further warming, which in turn causes more ice to melt. This creates a self-reinforcing cycle, where warming leads to more warming.

Conversely, in a cooling climate, ice cover can expand. Increased ice cover leads to higher reflectivity, which then causes more solar radiation to be reflected and less to be absorbed. This results in further cooling, promoting even more ice formation.

The jäätymisvaikutus is a key factor in understanding the sensitivity of Earth's climate system to changes in temperature. It plays a crucial role in amplifying both warming and cooling trends, making it a critical component in climate models and projections. Its impact is particularly pronounced in polar regions where ice cover is extensive.