Properties and Mechanisms of Seawater Exchange in Marian Cove, King George Island, West Antarctic Peninsula

The Antarctic Peninsula is one region that has recently experienced warming substantially more rapidly than the global mean over the past 50 years. Marian Cove is located in the South Shetland Islands connected to the Bransfield Strait via Maxwell Bay between King George Island and Nelson Island. In this study, we identified properties and mechanisms of seawater exchange in Marian Cove from multiple hydrographic surveys and a single bottom-mounted mooring installed at the entrance to Marian Cove. Regardless of the season, the mean current velocity profiles at the entrance to Marian Cove were constant because of the influence of tidal forcing. Wind was the primary force that determined the variation in surface current; in response, a countercurrent occurred near the bottom area. We estimated salt transport to understand what effects Maxwell Bay ' s saline water intrusion has on the Marian Cove environment. When the daily easterly wind was at its maximum of 18.5 m s(-1), the salinity could increase to 7.20 x 10(-4) g kg(-1) in 1 day. In addition, the average freshwater residence time in Marian Cove for the quantitative evaluation of seawater exchange was approximately 9 days. However, the freshwater residence time was reduced to less than 2 days when there were extreme easterly winds. In recent years, the Antarctic Peninsula has warmed up much faster than the global average. In the South Shetland Islands, Marian Cove is a small bay that connects to the Bransfield Strait through Maxwell Bay, which is between King George Island and Nelson Island. In this study, we used continuous observation devices at the entrance to Marian Cove to figure out how and why the seawater changes. Regardless of the season, inflow from the open sea occurs near the bottom due to the interaction of tides and friction forces. Wind was the main thing that changed the surface current, and as a result, the bottom current went in the opposite direction. We figured out how salt moves in Marian Cove, and the main thing that speeds up salt intrusion in Marian Cove is easterly wind. We try to estimate how long the water in Marian Cove stays there. On average, water can stay for about 9 days. However, when there were very strong easterly winds, the time was reduced to less than 2 days, which will be insufficient for phytoplankton growth. Tide-induced mean current was the primary factor sustaining mean seawater exchange at the entrance to Marian CoveSeawater exchange was mainly affected by wind forcingFreshwater residence time of Marian Cove was approximately 9 days and could be reduced to within 2 days by strong easterly winds