Posted: Oct 28, 2010 5:39 am
by HughMcB
Tagged Narwhals Track Warming Near Greenland

ScienceDaily (Oct. 27, 2010) — In a research paper published online October 27 in the Journal of Geophysical Research Oceans, a publication of the American Geological Union (AGU), scientists reported the southern Baffin Bay off West Greenland has continued warming since wintertime ocean temperatures were last effectively measured there in the early 2000s.

Temperatures in the study were collected by narwhals, medium-sized toothed Arctic whales, during NOAA-sponsored missions in 2006 and 2007. The animals were tagged with sensors that recorded ocean depths and temperatures during feeding dives from the surface pack ice to the seafloor, going as deep as 1,773 meters, or more than a mile.

Scientists have had limited opportunities to measure ocean temperatures in Baffin Bay during winter months because of dense ice and harsh conditions. Cost is also a factor -- it requires millions of dollars to mount a conventional expedition using an ice-breaking vessel and other specialized equipment and people. As a result, for the past decade, researchers used climatology data consisting of long-term historical average observations rather than direct ocean temperature measurements for winter temperatures in the area.


Tagged narwhals migrated south into Baffin Bay
where they collected and transmitted temperatures
from the pack ice through the following spring.
(Credit: NOAA/University of Washington)