On the phytoplankton bloom in coastal waters of southern King George Island (Antarctica) in January 2010: An exceptional feature?

• Published in: Limnology and Oceanography
• Main Authors: Schloss, Irene Ruth, Wasilowska, A, Dumont, D, Almandoz, Gaston Osvaldo, Hernando, Marcelo Pablo, Michaud Tremblay, C. A, Saravia, L., Rzepecki, M., Monien, P., Monien, D., Kopczynska, E. E., Bers, A.V., Ferreyra, G. A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Amer Soc Limnology Oceanography
• Subjects: Climate Change; https://purl.org/becyt/ford/1.6; https://purl.org/becyt/ford/1; Antarctic; Antarctic Peninsula; King George Island; Potter Cove; Admiralty Bay; Argentino; Argentina; 25 de Mayo; Gaston; Antarc*; Antarctica; Dirección Nacional del Antártico; Instituto Antártico Argentino
• Online Access: http://hdl.handle.net/11336/24800

Since the early 1990s, phytoplankton has been studied and monitored in Potter Cove (PC) and Admiralty Bay (AB), King George/25 de Mayo Island (KGI), South Shetlands. Phytoplankton biomass is typically low compared to other Antarctic shelf environments, with average spring—summer values below 1 mg chlorophyll a (Chl a) m−3. The physical conditions in the area (reduced irradiance induced by particles originated from the land, intense winds) limit the coastal productivity at KGI, as a result of shallow Sverdrup's critical depths (Zc) and large turbulent mixing depths (Zt). In January 2010 a large phytoplankton bloom with a maximum of around 20 mg Chl a m−3, and monthly averages of 4 (PC) and 6 (AB) mg Chl a m−3, was observed in the area, making it by far the largest recorded bloom over the last 20 yr. Dominant phytoplankton species were the typical bloom-forming diatoms that are usually found in the western Antarctic Peninsula area. Anomalously cold air temperature and dominant winds from the eastern sector seem to explain adequate light : mixing environment. Local physical conditions were analyzed by means of the relationship between Zc and Zt, and conditions were found adequate for allowing phytoplankton development. However, a multiyear analysis indicates that these conditions may be necessary but not sufficient to guarantee phytoplankton accumulation. The relation between maximum Chl a values and air temperature suggests that bottom-up control would render such large blooms even less frequent in KGI under the warmer climate expected in the area during the second half of the present century. Fil: Schloss, Irene Ruth. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Université du Québec à Rimousk; Canadá Fil: Wasilowska, A. Warsaw University; Polonia Fil: Dumont, D. Université du Québec à Rimousk; Canadá Fil: Almandoz, Gaston Osvaldo. Universidad ...