“Asian Monsoons” Affected By Seawater Temperatures

Seaside near the Shimoda Marine Research Center. (Credit: University of Tsukuba)

“Asian monsoons” affect the tropics to the mid-latitudes in Asia, where large areas experience wet and dry seasons. According to a release from the University of Tsukuba, years of data point to a decline in “Asian monsoon” rainfall over time. In addition, modeling results suggest the rainfall seems to be directly related to seawater temperature distribution in the tropical Pacific Ocean.

Because the rainfall is directly tied to not only flooding damage but also agricultural success, understanding the reasons behind the rainfall weather patterns and gaining the ability to predict them is of great importance. University of Tsukuba faculty performed numerical simulations using climate models and compared them to available rainfall data. They found a strong relationship between seawater temperatures in distant tropical regions and monsoon rainfall patterns that had altered in recent years.

An atmospheric general circulation model was used which contained hypothetical sea surface temperature distributions. In this way, scientists were able to accurately represent the summer rainfall of the past few years, wherein low rainfall was seen from northern China to Japan and high rainfall occurred over the Pacific Ocean. Results clearly indicated the influence of tropical Pacific Ocean seawater temperatures.

Top image: Seaside near the Shimoda Marine Research Center. (Credit: University of Tsukuba)