Large flux of iron from the Amery Ice Shelf marine ice to Prydz Bay, East Antarcticaстатья из журнала
Аннотация: Abstract The Antarctic continental shelf supports a high level of marine primary productivity and is a globally important carbon dioxide (CO 2 ) sink through the photosynthetic fixation of CO 2 via the biological pump. Sustaining such high productivity requires a large supply of the essential micronutrient iron (Fe); however, the pathways for Fe delivery to these zones vary spatially and temporally. Our study is the first to report a previously unquantified source of concentrated bioavailable Fe to Antarctic surface waters. We hypothesize that Fe derived from subglacial processes is delivered to euphotic waters through the accretion (Fe storage) and subsequent melting (Fe release) of a marine‐accreted layer of ice at the base of the Amery Ice Shelf (AIS). Using satellite‐derived Chlorophyll‐a data, we show that the soluble Fe supplied by the melting of the marine ice layer is an order of magnitude larger than the required Fe necessary to sustain the large annual phytoplankton bloom in Prydz Bay. Our finding of high concentrations of Fe in AIS marine ice and recent data on increasing rates of ice shelf basal melt in many of Antarctica's ice shelves should encourage further research into glacial and marine sediment transport beneath ice shelves and their sensitivity to current changes in basal melt. Currently, the distribution, volume, and Fe concentration of Antarctic marine ice is poorly constrained. This uncertainty, combined with variable forecasts of increased rates of ice shelf basal melt, limits our ability to predict future Fe supply to Antarctic coastal waters.
Год издания: 2016
Авторы: Laura Herráiz‐Borreguero, Delphine Lannuzel, Pier van der Merwe, Adam Treverrow, Joel B Pedro
Издательство: Wiley
Источник: Journal of Geophysical Research Oceans
Ключевые слова: Cryospheric studies and observations, Polar Research and Ecology, Arctic and Antarctic ice dynamics
Другие ссылки: Journal of Geophysical Research Oceans (PDF)
Journal of Geophysical Research Oceans (HTML)
OPAL (Open@LaTrobe) (La Trobe University) (PDF)
OPAL (Open@LaTrobe) (La Trobe University) (HTML)
eCite Digital Repository (University of Tasmania) (PDF)
eCite Digital Repository (University of Tasmania) (HTML)
Journal of Geophysical Research Oceans (HTML)
OPAL (Open@LaTrobe) (La Trobe University) (PDF)
OPAL (Open@LaTrobe) (La Trobe University) (HTML)
eCite Digital Repository (University of Tasmania) (PDF)
eCite Digital Repository (University of Tasmania) (HTML)
Открытый доступ: bronze
Том: 121
Выпуск: 8
Страницы: 6009–6020