Seasonal variability of marine temperature distribution of Tianjin coastal waters in the Bohai bay

Abstract

According to the in situ data of State 908 project during summer and winter cruise of 2006 , spring and autumn of 2007 in Tianjin coastal waters, the paper draws seasonal variability distribution map of marine temperature using Kriging spatial interpolation method in software ArcGIS 9.2. It discusses marine temperature characteristics of Tianjin coastal waters in the Bohai Bay, and makes the preliminary analyzes. The study shows that sea surface temperature in Tianjin coastal waters reaches the maximum value in the whole year, ranging from 24.72°C to 28.22°C while there doesn't exist obviously horizontal temperature gradient and strong front area. Sea water temperature of autumn cruise which ranges from 12.97°C to 15.77°C is distinctly lower than the data of the summer cruise while it hasn't obviously variability in horizontal temperature gradient. Sea water temperature of winter cruise which ranges from 2°C to 7.37°C has the minimum value in the whole year. Sea water temperature of spring cruise which ranges from 7.41°C to 12.19°C has a clear climb in comparison with the data of winter cruise. Seasonal prevalent distribute of sea surface temperature in summer and autumn is higher in the south area than in the north area in Tianjin coastal waters, while the distribution of sea surface temperature in winter and spring relates to runoff.