What can one do?

trump knows which campaign promises to keep in order to make sure his base is happy.  So, of course, he pulled the US out of the Paris agreement on limiting greenhouse gas emissions in order to try to keep the world from roasting.

Source

Der Spiegel notes in a lengthy editorial essay:

Trump's withdrawal is a catastrophe for the climate. The U.S. is the second-largest emitter of greenhouse gases -- behind China -- and is now no longer part of global efforts to put a stop to climate change. It's America against the rest of the world, along with Syria and Nicaragua, the only other countries that haven't signed the Paris deal.
But the effects on the geopolitical climate are likely to be just as catastrophic. Trump's speech provided only the most recent proof that discord between the U.S. and Europe is deeper now than at any time since the end of World War II.
Now, the Western community of values is standing in opposition to Donald Trump. The G-7 has become the G-6. The West is divided.

At this point, it seems like only a major volcanic eruption can cool the planet.  The downside to that eruption is, well, the the suddenness of it all will be catastrophic; be careful what you wish for!

So, what can one do on this World Environment Day, right?

Even if you are a New York billionaire--that other guy--there is not much you can do.

Unfortunately, private philanthropy is just not big enough to replace government funding. You can advocate. You can demonstrate.

As much as Bloomberg is putting his own money where his mouth is, we too can do things in our daily lives even as we continue to resist the maniac that 63 million people voted for.  Like, for instance, "You’re better off eating vegetables from Argentina than red meat from a local farm":

Eating local is lovely, but most carbon emissions involving food don’t come from transportation — they come from production, and the production of red meat and dairy is incredibly carbon-intensive.

And, yes, simplify your life:

It’s better not to consume the raw materials in the first place, so you may want to think carefully about whether you’re really going to use something before you buy it.

Oh, of course, continue to protest against the horrible human being and continue to shame the 63 million who voted for him.