Carbonate Characteristics of Waters of the Arctic Ocean Continental Slope

摘要

Carbonate characteristics of the water mass of the deepwater part of the Arctic Ocean (AO) in the continental slope area were determined, and the range and reasons of their variability during summer-fall season were revealed. The AO water area is a meaningful sink for atmospheric carbon dioxide. The warm intermediate Atlantic waters (AW) are also undersaturated with carbon dioxide relative to its content in the atmosphere. While these waters move along AO continental slope, the value pCO_2 in the AW core decreases to 8-10 fiatm (mainly, due to drop in the water temperature). The potential absorption capacity of the AO deepwater basin is estimated at approximately 48 Tg of carbon (without sea ice taken into account). Joint analysis of carbonate and hydrological parameters showed that near-bottom waters formed on the shallow shelf of the Laptev Sea, which is rich in inorganic and organic carbon of terrestrial and marine genesis, take part in formation of halocline waters of the AO. They are modified due to interaction with AW penetrating to the shelf and are transferred to the deepwater AO segment, where they occur in the halocline according to their density. Transformed near-bottom waters of the Laptev Sea shelf, similar to waters of the halocline of Pacific origin in the eastern sector of the AO, are traced above the continental slope in Amundsen Basin on the basis of higher CO_2 concentrations.