Photo by Brad Smith.

The forecast calls for a “Twitterstorm” Monday, thanks to a couple dozen environmental activist groups, including 350.org, Greenpeace International, and the Natural Resources Defense Council.

A “Twitterstorm” isn’t something out of Alfred Hitchcock’s The Birds; it’s a global campaign to raise a ruckus on Twitter by deliberately spreading a message — in this case, the call to end fossil fuel subsidies, or #endfossilfuelsubsidies, as the hashtag call will go out.