NSF Autonomous and Lagrangian Platforms and Sensors (ALPS) Workshop Report Application of ALPS Technologies to High-Latitude Science Issues

• Main Author: Craig M. Lee
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Greenland; Southern Ocean
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.571.3597; http://asofw.apl.washington.edu/assets/pdfs/polar_alps.pdf

The high-latitude oceans serve as freshwater sources and heat sinks for the global thermohaline circulation, exerting significant influence on ocean general circulation and climate variability. Warm surface flows carry heat toward the poles where intense heat loss to the atmosphere drives densification and produces an equatorward return flow of intermediate and bottom waters. This exchange establishes the meridional overturning circulation (MOC) which, when combined with the inter-basin exchange permitted by the zonally unbounded Southern Ocean geometry, supports the global thermohaline circulation. High-latitude convection thus ventilates the many mid- and low-latitude density layers which outcrop in the polar/subpolar oceans, setting subsurface density structure and removing carbon to the ocean interior. In contrast, net precipitation in the polar regions produces an equatorward freshwater flux that is largely confined to the upper ocean. Fresh waters exiting the Arctic can form a low-density surface barrier that inhibits convective overturning at the deep water formation sites in the Labrador and Greenland Seas, modulating the strength of the MOC and thus the exchange of heat from equator to pole. The high-latitude freshwater balance plays additional roles in the climate