Observations of water temperature and salinity in Ongul Strait, Antarctica, in 1998 and investigations of their intraseasonal, seasonal, and interannual variations

摘要

Water temperature and salinity variations were observed below fast ice in Ongul Strait, Antarctica, in 1998. Vertical profiles of temperature and salinity were obtained with a conductivity-temperature-depth profiler, and temperature and salinity were continuously observed with moored sensors. Intraseasonal variations were observed in both fields. Especially, temperature variation of about 0.05℃ was apparent on the time scale of about one month near the thermocline depth. Seasonal variations of temperature and salinity were similar to those observed in 1982-1983 and 1990-1991. However, the temporally averaged temperature and salinity for 1998 showed differences from those for previous years; temperature was higher in 1998 than in 1982-1983 and 1990-1991 at middle to deep layers, and salinity was intermediate between 1982 (more saline) and 1990-1991 (fresher) throughout the water column.