Résumé
As our planet’s climate warms, its most rapidly changing region is the Arctic Ocean and surrounding seas. Warming causes many changes, including the melting of sea ice and a decline in the amount of water that is covered by ice. These changes impact organisms at every level of the food web. In this article, we explain how changes in temperature affect the quality of food available for animals that live in the Arctic. We focus on changes near the bottom of the food web, involving tiny plants that dwell inside and below sea ice, and tiny animals that drift in the Arctic seas. Shifts in the abundance and quality of the smallest organisms in the Arctic Ocean affect larger organisms, such as polar bears and whales. Changes at the base of the food web must be considered if we want to protect the creatures that call the Arctic home.