Curious fish

This fish, which to me appears to be from tropical waters, was found washed up on Tyninghame beach in East Lothian. It was still alive when found, but died soon afterwards. Has anyone any idea what species of fish this is? Deep water or tropical? It is about 16 inches long, by 9 inches deep. At the moment it is being kept in a freezer pending more research. If it turns out that this is a tropical fish, does this event point to global warming. I wonder.