Record-breaking rainfall recently lashed southern Kyushu in southwestern Japan. The downpours came a year after torrential rain hit western Japan and left over 220 people dead or missing. In the latest disaster, a number of houses were damaged after being hit by landslides triggered by the rain.
From the time the rain began falling, the rainfall topped 1,000 millimeters in some areas. Residents in those areas need to be on the alert amid the threat of landslides and other risks. Caution is needed in some other areas, too, as the active seasonal rain front has caused the rain to spread to the Tokai region in central Japan and the Kanto-Koshin region in eastern Japan.
The latest rain marked the first downpours to hit Japan since the May introduction of the government's new five-tier alert system. The system outlines specific actions that residents of disaster-hit areas should take depending on the degree of risk.
Officials introduced the system following the torrential rains that hit western Japan in July 2018. During last year's disaster, warnings issued by the Japan Meteorological Agency (JMA) and evacuation advisories and orders issued by local bodies did not necessarily lead to residents' evacuation. Reflecting on this, the government has designed the new system to clearly show which alert levels correspond to information released by the JMA and local governments.
Level 3, at which senior citizens should begin evacuation, and level 4, at which all residents must flee, are keys to protecting residents' lives. It would be too late if residents began to evacuate after the alert level were raised to 5, by which time a forecasted disaster is highly likely to have occurred.
The central government and local bodies in areas affected by the latest heavy rain were quick to respond this time. In a rare move, the JMA held an emergency news conference on two consecutive days, and strongly urged residents to evacuate if a level-4 alert was issued. The alert system was not raised to that level, but the JMA indicated that it could issue a heavy rain emergency warning, which is equivalent to level 5.
In the southwestern Japan prefecture of Kagoshima, an evacuation order -- equivalent to level 4 -- was issued to over 1 million people. Gov. Satoshi Mitazono asked the Self-Defense Forces to dispatch personnel to the prefecture to respond to a possible serious disaster. In the future, there will be room for discussions on the appropriateness of the timing of issuing such a request.
In the end, less than 0.7 percent of those covered by the evacuation order and advisory in Kagoshima Prefecture fled to designated evacuation shelters. There are cases where it may be safer to flee to the upper floors of residences depending on the location and other conditions. It is necessary to examine whether government organizations' advice led to the appropriate evacuation of residents.
Linear rainbands, along which cumulonimbus clouds develop one after another, bringing heavy rain, were observed during the latest downpours. The phenomenon was also seen in the torrential rains in western Japan last year. We need to keep in mind that record-breaking heavy rain could fall anywhere at any time.
Those who fled their homes after the warning level was raised to 3 or 4 but in the end did not see any damage to their homes or neighborhoods should not think their evacuation was a waste of time. It is essential to make sure that a system under which government bodies advise residents of affected areas to evacuate at an early stage and residents respond to such calls takes root.