An average of almost 1,500 landslides rocked Japan every year during the past decade, marking an increase of almost 50 percent on the previous 10 years, according to a government report endorsed by the Cabinet on Friday.
The trend reflected the rise in torrential rainfall due to global warming, said the white paper on land, infrastructure and transport, which called for restrictions on the use of at-risk land and relocating residents to safer areas.
The average number of landslides per year was 1,006 between 2000 and 2009, but jumped 46.7 percent to 1,476 between 2010 and 2019. This compares with 1,027 between 1990 and 1999.
Downpours of 50 millimeters or more per hour in the past decade were recorded 1.4 times more frequently than between 1976 and 1985.
In 2018, Japan was hit by a record 3,459 landslides, triggered by torrential rain in western Japan and a major earthquake in Hokkaido. Last year, Typhoon Hagibis and other torrential rainfall triggered 1,996 landslides.
Japan this month made legal moves to tighten restrictions on the development of red-zone areas, where residents’ lives are at greatest risk in the event of landslides, and to introduce a system for municipal governments to offer relocation, the report said.
It added Japan will seek to reduce flood damage by enhancing embankments, creating underground water storage facilities, and promoting evacuation in key areas.
Meanwhile, the Meteorological Agency warned of landslides, especially in the northern part of the Kyushu region hit by torrential rain this week.
A downpour of more than 80 millimeters per hour was reported in Sasebo, Nagasaki Prefecture, on Thursday, and the agency predicts another 80 millimeters of rain in northern Kyushu in 24 hours up to 6 a.m. Saturday.
A 6.1-magnitude earthquake struck off eastern Japan early Thursday, registering lower 5 on Japan’s seismic intensity scale of 7 in Asahi, Chiba Prefecture. Although there were no reports of landslides following the quake, the agency warned quakes of similar intensity may follow over the next week in areas that experienced strong swaying.
The National Police Agency said Thursday it is preparing to launch in August a website where citizens can post photos and video clips taken on their smartphones in times of major disasters, so that authorities can swiftly control traffic and begin relief activities.
The agency will solicit images of things such as damaged roads, collapsed buildings and landslides caused by earthquakes, typhoons and heavy rain to be posted via the website, which will only be launched at the time of a major disaster.