James McCarthy

James J. McCarthy is the Alexander Agassiz Professsor of Biological Oceanography at Harvard, and president of the American Association for the Advancement of Science.

Recent Articles

The Arctic Ocean in the 21st Century

With warming at a rate double the global average, the region's animal populations struggle to adapt.

Observations of Earth's climate over the past half-century reveal a global trend in warming temperatures of land surfaces, the lower atmosphere, and the oceans. The Arctic region is warming at a rate that is at least twice that of the global average. This is particularly evident in the central Arctic, two-thirds of which is the Arctic Ocean. In contrast to the Antarctic, which is dominated by a central continent and an enormous mass of ice with an average elevation of 7,500 feet, much of the Arctic is at sea level. The low elevation of the Arctic (and thus the greater sensitivity to surface warming), the effect of open water and bare land absorbing more solar-radiant energy than ice and snow, and the fact that water holds heat more effectively than land all contribute to the sharp difference in warming rates observed for Earth's two polar regions. Arguably no ocean is changing now or is likely to change in the near future as rapidly as the Arctic Ocean. It is the extensive year-round...