As the season progresses, the Arctic ice layer becomes larger and smaller. A thick layer of ice will continue to exist at the edge. Even in summer, it does not melt. We call it perennial sea ice (pink in the picture below), but the global average temperature has been rising. Scientists have found that over the past 40 years, years of sea ice have become unbearable and have begun to shift from 7 million square kilometers, leaving only 4 million square kilometers, which is equivalent to the size of India. When years of sea ice melt, this means that there is no ice in the Arctic during summer. The Blue Ocean Incident This means that only when the water in the Arctic Ocean turns blue and the white without ice is visible.