### h. Issuing Sediment Disaster Alert

When the risk of sediment disasters occurring increases due to heavy rainfall, sediment disaster alert is jointly issued by prefectures and the Japan Meteorological Agency and disseminated through the fire protection and disaster preparedness section of the prefecture to assist the head of the municipality with deciding on giving evacuation orders as well as allow residents to evacuate on their own.

# Emergency Warnings Begin Operations

Massive damage is caused by natural phenomena of extraordinary magnitude in Japan, as exemplified by the major tsunami caused by the 2011 Great East Japan Earthquake and heavy rain caused by Typhoon Talas in the same year. In response to these natural hazards, the Japan Meteorological Agency (JMA) issued warnings and various other messages. However, in some cases there was no effective means of informing municipalities and residents of a significant risk if imminent fatal disaster in association with natural phenomena on a scale far exceeding the regular warning criteria, and existing warnings and other information did not prompt residents to evacuate urgently. Based on these experiments, JMA introduced the Emergency Warning System on August 30, 2013, to highlight such hazards.

Emergency Warnings are intended for extraordinary phenomena expected to be of a scale that will far exceed the warning criteria. The criteria for Emergency Warning issuance were determined in response to the views of local governments in charge of disaster management for their own areas. Regarding heavy rain, storm, storm surge, high waves, snowstorms, and heavy snow, when an phenomenon that only occurs once every few decades is forecast, an Emergency Warning capping the name of the phenomenon is issued. On the other hand, for tsunamis, volcanic activity, and seismic motion, Major Tsunami Warnings, Volcanic Warnings (residential areas) $ ^{Note} $ , and Earthquake Early Warnings (EEW) incorporating prediction of tremors measuring six-lower or more on JMA's seismic intensity scale are considered Emergency Warnings and are issued in the classification of Emergency Warnings respectively.

Also, regarding Emergency Warnings, to ensure that it is transmitted to as many residents as possible swiftly and surely, measures for notifications from prefectures to municipalities and dissemination to residents by the municipalities are both mandatory.

Furthermore, remember that catastrophes may occur even if no Emergency Warning is in effect. For heavy rain and other events, it is important to take early action with reference to relevant bulletins, Advisories and Warnings, which are updated in response to the latest phenomenon observations or predictions.

Phenomenon	Criteria
Heavy Rain	·Heavy rainfall with a level of intensity observed only once every few decades is predicted in association with a typhoon or similar. Or: ·Heavy rainfall is predicted in association with a typhoon expected to have a level of intensity observed only once every few decades or an extratropical cyclone with comparable intensity. (Note)
Storm	A storm is predicted (Note)	in association with a typhoon expected to have a level of intensity observed only once every few decades or an extratropical cyclone with comparable intensity.
Storm Surge	A storm surge is predicted (Note)
High Waves	High waves are predicted (Note)
Snowstorm	A snowstorm is predicted in association with an extratropical cyclone expected to have a level of intensity observed only once every few decades. (Note)
Heavy Snow	Heavy snowfall with a level of intensity observed only once every few decades is predicted. (Note)
Tsunami	Tsunami height is expected to be greater than 3 meters (Major Tsunami Warnings are issued in the classification of Emergency Warnings)
Volcanic Eruptions	Eruption or possibility of eruption that may cause serious damage in residential areas and non-residential areas nearer the crater (Volcanic Warning [Level 4 and 5] and Volcanic Warning [residential areas] are issued in the classification of Emergency Warnings)
Earthquake	Seismic intensity of 6-lower or more is predicted (Earthquake Early Warnings incorporating prediction of tremors measuring 6-lower or more on the Japan Meteorological Agency's seismic intensity scale are issued in the classification of Emergency Warnings)

(Note) The Japan Meteorological Agency (JMA) issues Emergency Warnings by taking account of the latest phenomenon observations, predictions, and the objective indices for issuance of Emergency Warnings made in light of past catastrophes. JMA's website provides the objective indices for variables such as rainfall amounts used for the definition of a level of intensity observed only once every few decades.

Source) Japan Meteorological Agency

Note When residential areas are not defined, “residential areas” is replaced with “foot-of-mountain areas”.