Which communication method is primarily used for emergency situations at sea?

VHF Radio is primarily used for emergency situations at sea because it is specifically designed for marine communication, providing reliable and immediate connections between vessels and shore stations. In emergency scenarios, VHF radios support distress calls through the dedicated channel 16, allowing users to broadcast an emergency situation to all nearby vessels and receiving prompt responses.

Additionally, VHF radios have a clear line of sight range, which is often sufficient in coastal waters and can facilitate communication over significant distances. This method of communication is vital during emergencies as it operates in real-time, ensuring that help can be summoned quickly and efficiently. While other communication methods, like flares and mobile or satellite phones, may also be used in emergencies, they do not offer the same combination of immediacy, range, and established protocols that VHF radios do in maritime contexts.