Author(s): Kohei Kamimura; Hitoshi Miyamoto
Linked Author(s): Hitoshi MIYAMOTO
Keywords: No Keywords
Abstract: In this paper, the trend of long-term change and its factors in annual mean equilibrium water temperatures were examined all over Japan for recent 50 years from 1963 to 2012. For statistical assessment of time series data in the equilibrium water temperatures, Mann-Kendall test was used to detect a warming or cooling trend and Sen’s slope was used to evaluate its quantitative values. The results showed that there were both warming and cooling trends in the long-term changes of the equilibrium water temperatures. As for their regional distribution characteristics, the temperature warming trend was obvious in the coastal part of the Pacific Ocean in west Japan. This coastal part could be influenced from both the global warming and urban heat island phenomenon as well. On the other hand, the temperature cooling trend was detected in the northern part, i. e., Tohoku, and the southern part, Kyushu regions as well as the coastal part of the Sea of Japan. These parts indicated a strong tendency on either a decrease in short wave radiation or an increase in latent heat transfer.
Year: 2018