Construction of Bulk Temperature/Salinity from Surface Temperature and Atlas Profiles for Monitoring Water Volume Variations in the Caspian Sea

Construction of Bulk Temperature/Salinity from Surface Temperature and Atlas Profiles for Monitoring Water Volume Variations in the Caspian Sea

Unlike the other lakes, the Caspian Sea has regular water level fluctuations caused by variation in temperature and salinity, which is known as thermohaline fluctuations. Vertically variable temperature and salinity data are needed in order to monitor thermohaline fluctuations. These data are regularly recorded for the open seas by remote sensing and in-situ approaches. However, there is no such information for inland water bodies, such as the Caspian Sea. In this research, daily Sea Surface Temperature (SST) from the NOAA satellite, plus long-term mean temperature, and salinity datasets from Atlas 2009 were utilized to construct bulk temperature and salinity in the Caspian Sea. The Atlas vertical profiles are not deep enough in the Caspian Sea; we expanded these data down to a thermocline depth, using a linear fitting. Constructed bulk temperature and salinity data utilized in water density calculations. The results show that thermohaline level fluctuation estimated by constructed bulk data is consisted of what a combination of altimetry and gravimetry system observed in the Caspian Sea. In the absence of necessary data, this method is helpful for bulk temperature and salinity estimations in the Caspian Sea with a satisfactory level of accuracy. The estimated thermohaline has an accuracy of about 93%, under the situation that there was 15% error in the estimation of both bulk temperature and salinity.

Unlike the other lakes, the Caspian Sea has regular water level fluctuations caused by variation in temperature and salinity, which is known as thermohaline fluctuations. Vertically variable temperature and salinity data are needed in order to monitor thermohaline fluctuations. These data are regularly recorded for the open seas by remote sensing and in-situ approaches. However, there is no such information for inland water bodies, such as the Caspian Sea. In this research, daily Sea Surface Temperature (SST) from the NOAA satellite, plus long-term mean temperature, and salinity datasets from Atlas 2009 were utilized to construct bulk temperature and salinity in the Caspian Sea. The Atlas vertical profiles are not deep enough in the Caspian Sea; we expanded these data down to a thermocline depth, using a linear fitting. Constructed bulk temperature and salinity data utilized in water density calculations. The results show that thermohaline level fluctuation estimated by constructed bulk data is consisted of what a combination of altimetry and gravimetry system observed in the Caspian Sea. In the absence of necessary data, this method is helpful for bulk temperature and salinity estimations in the Caspian Sea with a satisfactory level of accuracy. The estimated thermohaline has an accuracy of about 93%, under the situation that there was 15% error in the estimation of both bulk temperature and salinity.