I keep ranting about cruise ships, no doubt partly because I can see them from here for about six months of every year. I should start ranting about gigantic yachts, too.

There is much more at stake in this burgeoning market than these yachts’ purchase prices. Megayachts are an increasing blight on our societies, and the world would be better off without them.

First and foremost, owning a megayacht is the most polluting activity a single person can possibly engage in. Abramovich’s yachts emit more than 22,000 tonnes of carbon every year, which is more than some small countries. Even flying long-haul every day of the year, or air-conditioning a sprawling palace, would not get close to those emissions levels.

And all for what? Fun. Pleasure. Entertainment. It’s like burning down Yosemite to toast some marshmallows.

How about a global law against building them?

In the case of nuclear weapons, our collective safety has been advanced by nonproliferation treaties, which undermine the spread of missiles and encourage their gradual withdrawal. Some activists, academics and policymakers have argued that the approach should now be applied to fossil fuels, which pose just as grave a threat to our future. A megayacht nonproliferation treaty would see countries agreeing to stop building vessels beyond a specific size.

Any effective approach will also have to target existing yachts, though, and not only new ones. Their outsized carbon footprint means that megayachts are catastrophic contributors to the climate crisis simply by virtue of existing.

But the people who could draw up such a treaty probably all want to be guests on some of those yachts themselves.