Why has the temperature of the Arctic Ocean changed during the last 40 years? Sea ice has melted allowing more sunlight to hit the ocean, less snow falls in the Arctic now then 40 years ago, more sunlight now reaches earth than in the past, or sea ice has produced more salt causing the cold ocean water to sink

1 answer

The temperature of the Arctic Ocean has changed over the last 40 years primarily due to two factors: the melting of sea ice and the increase in sunlight reaching the ocean.

1. Melting sea ice: The Arctic region is experiencing significant melting of sea ice due to global warming. As the Earth's temperature has risen, the Arctic sea ice has been reducing at an alarming rate. Less ice cover means more open water, which absorbs more sunlight. This process amplifies warming, as solar radiation is absorbed by the ocean instead of being reflected back into space.

2. Increase in sunlight: The reduction in sea ice cover allows more sunlight to directly reach the surface of the Arctic Ocean. Sea ice usually reflects sunlight back into space, acting as a natural barrier. When the ice melts, more sunlight is absorbed by the dark ocean waters, leading to warming. This phenomenon, known as the ice-albedo feedback, contributes to further temperature increases in the Arctic.

It's worth noting that the amount of snowfall in the Arctic has decreased over the years, but this is a secondary factor compared to the melting of sea ice and increased sunlight absorption. Additionally, the salt content of sea ice does not significantly affect the temperature of the Arctic Ocean.