Using δ18O as a Tracer of the Formation of Water Masses in the Laptev Sea. Part 1. Quantification of Ice Formation and Melting

Resumo

Data on salinity and δ¹⁸O from the NASA open-source database are used to estimate the Laptev Sea water mass transformation during ice formation and melting. The indicator of these processes is salinity variation. The estimates for the Laptev Sea show that the amount of meltwater can reach 40% for the sea water with salinity below 7 psu. In this case, sea water salinity reduction due to the meltwater inflow alone can be equal to 0.2-0.7 psu. In the sea water with salinity above 7 psu, ice formation prevails over ice melting. This process is the most strongly pronounced in the range of sea water salinity from 15 to 25 psu. In this salinity range, the average water removal for the ice formation makes up 9% (the maximum is 24%), and the average salinity growth is 0.5 psu (the maximum is 1.7 psu). The most transformed sea water masses during ice formation are located in the bottom layer of the shallow southern and southeastern parts of the Laptev Sea, where the sea depth is not more than 50 m.