Which SEA AREA includes the polar regions beyond 70° latitude?

Which SEA AREA includes the polar regions beyond 70° latitude?

• A. SEA AREA A4
• B. SEA AREA A3
• C. SEA AREA A2
• D. SEA AREA A1

Answer: (A)

Understanding how SEA AREAS are defined for GMDSS radio coverage. The polar regions beyond 70° latitude are designated as Sea Area A4 because traditional VHF coast radio (A1) and MF/HF coverage (A2) do not reach those extreme latitudes, and the remaining global coverage is handled by satellite-based systems (A3). In practical terms, A1 covers areas within the VHF coast radio range, A2 extends MF/HF coverage offshore, and A3 covers the majority of the world’s oceans via satellite. Since the polar regions lie outside these networks’ reach, they belong to A4. Therefore, the correct area is the polar regions beyond 70° latitude.

Understanding how SEA AREAS are defined for GMDSS radio coverage. The polar regions beyond 70° latitude are designated as Sea Area A4 because traditional VHF coast radio (A1) and MF/HF coverage (A2) do not reach those extreme latitudes, and the remaining global coverage is handled by satellite-based systems (A3). In practical terms, A1 covers areas within the VHF coast radio range, A2 extends MF/HF coverage offshore, and A3 covers the majority of the world’s oceans via satellite. Since the polar regions lie outside these networks’ reach, they belong to A4. Therefore, the correct area is the polar regions beyond 70° latitude.