Popis: |
The current climate change episode has impacted sea ice in the 2 polar regions differently. In the Arctic, remarkable sea ice extent and thickness declines have been observed with a stunning depletion rate of old ice. No similar changes have been observed in the Antarctic. In this paper, the question posed in the title is addressed by reviewing findings retrieved from previous publications. The paper starts by identifying key geographic and climatic features and sea ice characteristics in the 2 polar regions and summarizing relevant recent records. It then proceeds by investigating interactions between sea ice and environmental factors, including atmospheric, oceanic, and dynamic aspects in each region, as well as the increasing number of icebergs in Antarctica. It is concluded that peculiarities of each polar region render the response to climate change differently. Researchers should not apply scenarios regarding the impacts of climate change on Arctic sea ice (i.e., retreat) to Antarctic sea ice. Instead of asking why Antarctic sea ice has not responded to climate change in the same way as Arctic ice, a more reasonable question could be why Arctic ice changes are yielding an annual cycle that resembles that of Antarctic ice. Under current global warming conditions, old ice entrapment within the Arctic basin is relaxed. This could result in Arctic sea ice becoming predominantly seasonal during winter and almost completely melted during summer, which is the current state of Antarctic sea ice. |