On August 19th, we observed an evening calm using a pilot balloon at the North Block, Saiwai-cho Campus, Kagawa University and around the Kotougawa River, Konan-cho. One graduate and two undergraduates from Kagawa University participated in this survey.

An evening calm is the windless weather in the evening when an onshore breeze turns into a land breeze. This phenomenon is especially remarkable in Takamatsu Plain. An evening calm is related to the heat environment at night caused by global warming, so Kagawa University has also been researching on it.

According to the AMeDAS Konan located at Takamatsu Airport, a relatively strong wind blows from the mountains during the night. In this observation, we planned to see how the wind blows around Kagawa University which is 13.5km north of the airport and the vertical thickness of the onshore/land breeze.

Picture of the Observation