The US Coast Guard issued Marine Safety Information Bulletin (MSIB) 05-21 to provide a brief overview of the Global Maritime Distress and Safety System (GMDSS) Worldwide Navigational Warnings Service.
he IMO, in cooperation with the International Hydrographic Organization and World Meteorological Organization, established a worldwide navigational warnings service to ships. A total of 21 navigational and meteorological areas (NAVAREAs and METAREAs) were established with responsibility for coordination and broadcast assigned regionally to various countries.
In the US, the National Geospatial-intelligence Agency (NGA) was assigned responsibility for NAVAREAs IV and XII. Similarly, the National Oceanic and Atmospheric Administration is responsible for METAREA IV and XII. Most NAVAREAs also post their navigational warnings online.
Ships fitted with an inexpensive GMDSS Inmarsat-C or Iridium LT-3100S ship earth station will receive these international NAVAREA and METAREA warnings, as well as alerts from rescue coordination centers.
These satellite terminals can also transmit distress alerts and communicate with rescue coordination centers globally. The five Arctic NAVAREAs and METAREAs XVII through XXI are fully covered by Iridium.
The publication follows a report of 30 August that over 50 warships were involved in Russian Navy exercises that surprised Alaska trawlers. Although many fishing in the area were caught by surprise, a warning of the planned exercise was broadcast by satellite to shipping over the GMDSS Worldwide Navigational Warnings Service on 19 August, five days prior to the start of the exercise.
Under GMDSS, all ocean-going passenger ships and cargo ships of 300gt and above conducting international voyages must be equipped with radio equipment that complies with international standards.
The 7th session of IMO’s Sub-Committee on Navigation, Communications and Search and Rescue (NCSR) in January 2020 decided on the modernization of the GMDSS. Amendments are expected to enter into force in 2024.