Japan's Meteorological Agency has released details of a new system to provide information on a possible huge quake along the Nankai Trough.

The undersea subduction zone extends off the Pacific coast of central and western Japan and scientists believe it could be the source of a possible mega earthquake.

The new system will go into effect on November first. It will mark a major shift from the agency's earlier approach that had focused on predicting a major quake in central Japan.

Under the new system, the agency plans to release regular evaluations, as often as once a month, on the risk of an earthquake along the trough.

The agency will also issue emergency information after abnormal phenomena are observed.

The abnormal phenomena could include quakes that register magnitude 7 or higher or an unusual change in the measurements of strain gauge monitoring systems.

A panel of experts will look into whether there is any connection with a possible mega quake.

The agency will also alert people should the experts conclude that the possibility of a mega quake has increased.

The emergency information will come in 2 stages. The first notice will state that the experts are going to meet to discuss the abnormal phenomena.

The second-stage information will report on what the panel finds. For example, it may say that the possibility of a mega quake could be increasing.

The agency says it will also advise residents on what steps they should take to protect themselves but has stopped short of presenting details.

Experts predict that, in a worst-case scenario, a magnitude-9 earthquake along the Nankai Trough could leave more than 320,000 people dead.

Source: ANNnewsCH