ilmastonmuistevyys

Ilmastonmuistevyys, often translated as climate memory or climate inertia, refers to the Earth's tendency to retain its climate state for a prolonged period even after external forcing has changed. This phenomenon arises from the slow response of various components of the Earth system, such as oceans and ice sheets, to changes in factors like greenhouse gas concentrations or solar radiation.

The oceans play a significant role in climate memory due to their vast heat capacity. They absorb and release heat very slowly, meaning that even if atmospheric temperatures were to stabilize, the oceans would continue to warm or cool for decades or even centuries, influencing surface temperatures and weather patterns. Similarly, large ice sheets, like those in Greenland and Antarctica, have a very slow melting or growth rate. Their presence or absence has a substantial impact on Earth's albedo (reflectivity) and sea level, and their response to warming or cooling takes centuries to millennia.

This inertia means that past emissions of greenhouse gases continue to exert a warming influence on the planet, and the effects of any future emissions reductions will not be immediately apparent. Understanding climate memory is crucial for projecting future climate change and for assessing the long-term consequences of current human activities. It highlights the commitment of future climate based on past and present emissions.