Spatial and temporal variation in shallow seawater

DAVID K. A. BARNES1, VERONICA FUENTES2, ANDREW CLARKE1, IRENE R. SCHLOSS3 AND

DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY

Año: 2006 p. 853 - 865

0967-0645

The variability of Southern Ocean sea surface temperatures (SST) are important to understanding coastal biology yet are poorly known amongst biologists. We compare sea temperatures at a constant depth (10-20 m) at coastal localities both sides of the Polar Front, around the Scotia Arc, the West Antarctic Peninsula and at high oceanic latitudes (around the margins of East Antarctica). We assess the wider context of these values by investigating minimum, maximum temperatures and ranges throughout the Southern Ocean using remotely sensed SST data. Data to date do show weekly, daily and hourly variation in shallow sea temperature can be a third of total annual variability (in the summer) but can be very constant (in winter). From comparison across scales in time and space the strong seasonal signal is the most striking feature of Antarctic shallow sea temperatures even at most high oceanic latitude sites. The winter sea temperatures at localities within the PF are similar (near freezing) but upper temperatures and thus the annual range varies predictably with latitude in a cline. This amounts to 0.2°C annual range / 100km of latitude between ~54°S and 67°S. The annual range in sea temperatures is little different at subAntarctic islands, whether they are north or south of the PF