Senate Democrats have staged an all-night filibuster to urge congressional action on global warming. The all-night marathon began at 6:30 Monday evening, with over two dozen senators taking part. Senators Edward Markey of Massachusetts and Barbara Boxer of California said Republicans who deny global warming are ignoring an existential threat.

Sen. Edward Markey: “The planet is running a fever, but there are no emergency rooms for planets. We have to engage in the preventative care so that we deploy the strategies that make it possible for our planet to avoid the worst, most catastrophic effects of climate change.”

Sen. Barbara Boxer: “We all know that all senators care deeply about their constituents and their families; if any one of us saw a danger looming, we would do everything in our power to save them. And yet, in the face of irrefutable scientific agreement, the Senate does nothing to make sure that polluters pay for the carbon they emit which will move us to a clean energy economy and away from catastrophic climate change.”

Despite the unprecedented effort to promote climate action, it took over three hours before the first call was heard for what environmentalists see as one of the most immediate and important steps that Washington can take: rejecting the Keystone XL oil pipeline. Senator Tim Kaine of Virginia made the demand, saying: “Why would we embrace tar sands oil and backslide to a dirtier tomorrow?” Environmentalists say Keystone would produce a devastating amount of carbon emissions through the extraction of tar sands oil in Canada.