Crustal response to the 2024 September disastrous rainfall in the northern Noto Peninsula, Central Japan

Crustal response to the 2024 September heavy rain episode in the northern Noto Peninsula, Central Japan, was studied using a dense network of global navigation satellite system receiving stations. Over the region in and around the Noto Peninsula, the regionally integrated subsidence was proportional to the daily rain, i.e., ~ 0.1 km ³ volumetric subsidence occurred in response to 1 Gt daily rain. The subsidence lasted for only a day or so. These findings are consistent with past cases of elastic response of the Japanese Islands lithosphere to rain loading. We also found that a small island, to the north of the peninsula, subsided by a few centimeters on heavy rain days. This cannot be explained by terrestrial water storage loads within the island. Rainwater may have remained partly in the ocean surrounding the island and depressed the ocean floor as a surface load.