What is this antenna for?

[VK3LU]

In recent years we have been holidaying at Palm Cove FNQ. On the jetty there is a met. installation that measures tides, wave height etc. But the one thing that has intrigued me is what looks like an HF antenna. It is made of aluminium so it cannot be a multi wavelength vhf antenna. I have been trying to think of a reason for using HF for relaying info from the installation there but I am at a loss. It must be to cover reasonable distances.If someone wants to scale the antenna the gentleman standing on the deck below it is a six footer or very close in my judgement.

Does anyone know the answer?

Nev