A research group at Hokkaido University announced that it was possible to analyze from artificial satellite data that the ground is temporarily slightly distorted due to the weight when a large amount of rain falls.
Research groups such as Professor Kosuke Hioki of Hokkaido University analyzed the data of a positioning system that combines multiple artificial satellites using a new method, and investigated changes in the height of the ground surface.
We investigated about 600 reference points of the Geographical Survey Institute in various parts of western Japan, and when we analyzed the data on the day when it rained heavily, we could confirm that the surface of the earth tended to drop slightly as the amount of rainfall increased.
When the rain stopped, it returned in about a day, and the research group found that the weight of the rain temporarily distorted the surrounding ground.
During the heavy rain that caused damage to various parts of Japan in July last year, it was confirmed that it tended to sink at the reference point of the rainy area such as Kyushu, Shikoku, and Chugoku region, and the average of this area was about 1 cm. It means that it was out.
Professor Hioki said, "The surface of the earth is covered with rocks and is thought to be hard, but it turned out to be slightly distorted when heavy rains put a heavy weight on it."