Anatahan’s ash emission goes on

Anatahan’s volcano continues to emit huge amounts of ash into the air as its volcanic activity continues with fluctuating magnitude.

In a joint report yesterday, the U.S. Geological Survey and the Emergency Management Office said ash plume rose to 10,000 feet and headed west-northwest.

The ash plume extended about 215 nautical miles west-northwest of the island as of yesterday morning, the agencies said.

The agencies said seismicity on Anatahan has been fluctuating for the past few days. However, they said that the occurrence of long-period earthquakes have become more frequent. Anatahan’s seismic stations have been fully restored after malfunctioning in the past weeks.

Recently, huge emissions of ash from Anatahan’s erupting volcano spread to different directions, with ash plume reaching Saipan and Tinian and as far west to the Philippines. Hazy conditions resulted in the cancellation of at least one local commercial flight and poor visibility in the Philippines.

Anatahan’s strongest historical eruption happened last April 6, with the volcano spewing ash some 50,000 feet into the air. The USGS said the volcano expelled about 50 million cubic meters of ash in that eruption.

Volcanic ash emissions have been a major concern for various federal and local agencies, which claimed that volcanic ash threatens aviation safety.

Volcanic ash threatens jets and aircraft in the air, as it forms deposit in engines, restricts airflow, and clogs fuel nozzles. Minute particles of volcanic ash also contaminate aircraft’s ventilation, lubrication, hydraulic and electronic systems. They cause erosion and pitting of leading edges of windshields and landing lights, as well as erosion of compressor blades.

Last week, representatives from various agencies convened on Saipan to lay the groundwork for a volcanic ash response plan for the CNMI. The agencies included the EMO and the USGS, Federal Aviation Administration, National Oceanic and Atmospheric Administration, National Weather Service, Air Force Weather Agency, and the Commonwealth Ports Authority, among others.

James Quick, the USGS’ volcano hazards program coordinator, said the operational plan would define the role of each agency in monitoring volcanic activities for to enable a rapid and systematic response. (John Ravelo)