SOUTHWEST HARBOR — In the 1973 movie “Soylent Green,” Earth is grossly overpopulated and broiled by global warming. “How can anything survive in a climate like this?” asks Thorn, a New York cop played by Charlton Heston. “A heatwave all year long. A greenhouse effect. Everything is burning up.” The city is packed with sweaty crowds that riot if denied their weekly handout of Soylent Green crackers, officially touted as “the miracle food of high-energy plankton gathered from the oceans of the world.”

While investigating a murder, Thorn stumbles on a classified document, the Soylent Oceanographic Survey Report: 2015 to 2019. (Yes, 2019.) The ocean, it says, is dying, even its plankton. Soylent Green, as Thorn eventually figures out, is secretly being made from the only resource left: corpses. Hence, the line shouted by Thorn as he is carried off bleeding: “Soylent Green is people!”

It’s a fable, not a forecast, but it gets some things disturbingly right. As for “burning up,” 2014-2018 were the five hottest years in observed weather history, and last July was the hottest month. In the last decade Greenland melting has doubled, Antarctic melting tripled, sea-level rise accelerated. In August the Intergovernmental Panel on Climate Change released its Special Report on the Ocean and Cryosphere in a Changing Climate, a real-life counterpart of the Soylent Oceanographic Survey Report. The oceans have absorbed over 90 percent of the heat added to the Earth over the last 50 years. Acidification by CO₂ is weakening all their shell-building creatures, including plankton. Marine heatwaves are creating huge oxygen-depleted dead zones. Over 90 percent of coral reefs could be dead by 2050.

And what about dear old Maine? If warming continues unabated, today’s toddlers will live to see our climate become like that of Virginia and the sea rise between 3 and 6.5 feet. Evergreens will die, insect-borne diseases spread, lobsters leave. Yet no list of local effects conveys our danger. Almost everything we eat and use depends on the global economic web, and if that begins to sag and snap under the weight of fire, flood, drought, ailing seas and the like, we will have even bigger problems than rampant ticks and scarce lobster.

Civilization won’t end tomorrow, but its catastrophic contraction within a generation or so has become plausible. Sober science journals warn that within a few decades we may tip the planet into an out-of-control Hothouse Earth state: killer heat, fires and floods, collapsed markets, billions of desperate people on the move, ubiquitous crop failures. Ultimately, not enough to eat. The Hollywood dream-weavers of 1973 prophesied our situation’s urgency pretty well. Mother Earth is screaming as she pounds the panic button. Washington Post, Nov. 26: “In bleak report, U.N. says drastic action is only way to avoid worst effects of climate change.”

Fortunately, there is a plan. It’s big and fast-moving, like the threat it counters, and daring, like all marvelous works, but practical, too. It is the Green New Deal as articulated by Bernie Sanders:

Invest $16.3 trillion in federal funds over just 10 years – less than the government committed to the bank bailout of 2008 – to turn things around. Make our electricity 100 percent carbon-free (and cheaper) by 2030 by building mass amounts of publicly owned solar and wind power. Electrify all transport, replacing our carbon-farters with U.S.-built electric vehicles. Expand public transportation, rebuild the grid, retrain people displaced fro­­m dirty-energy jobs, save family farms, lead global emissions cuts and more. Create 20 million U.S. jobs in the process. And do all this while raising up groups historically denied their fair share of prosperity – the working class, Native Americans, people of color, the disabled – most of us, in fact.

Bernie’s plan is uniquely thorough and serious, the only one that puts the pedal to the metal. Elizabeth Warren proposes a fifth as much funding; Joe Biden offers a nothingburger with extra nothing. Want hope? Vote for Bernie on March 3.

Yet no project this big can be accomplished by electing one person to any office. We must be a movement beyond voting and bigger than elections: learning, speaking, organizing, acting up.

Like Soylent Green, only different – as different as life is from death. The Green New Deal is people.