A recent United Nations climate change report did garner headlines, but no Maine media covered a related paper from the American Association for the Advancement of Science (AAAS) titled “What We Know.” That’s a shame because – unlike the 2,500-page U.N. report – the brief AAAS synopsis is a sound bite crying for our attention.

“What We Know” represents an unprecedented effort by leading scientists to awaken us to “the extraordinary future risks” and “massively disruptive consequences” of delaying action on climate change. When a group as large and credible as the AAAS, with more than 120,000 scientists worldwide, steps out of the lab to shake us by the shoulders, it pays to heed what they say.

On their site (http://whatweknow.aaas.org) are videos of glaciologists, oceanographers, geologists and geographers speaking in heartfelt language about their fears for the future. Gone is the typical technical jargon. In its place are everyday metaphors – comparing climate mitigation to a homeowner’s insurance policy, and likening the 97 percent consensus among climate scientists (on the reality of human-induced climate change) to the medical consensus linking smoking and cancer.

Scientists are increasingly frustrated because “the country can’t seem to get a grip on this issue,” says Alan Leshner, CEO of AAAS and a psychologist by training. “What We Know” stops just short of saying Americans are in complete denial: “We are acting like people who take risks with their health … but still (hope) to live long lives free of serious illness.”

If we don’t swallow a dose of reality soon, the prognosis is grim. “Each degree of warming costs more than the previous one,” notes Richard Alley, a glaciologist at Penn State University. The price paid for the 1.4-degree Fahrenheit increase to date has been relatively small, but each additional degree will extract a much greater societal and ecological cost. Climate change packs a nasty punch: If we wait until the full force of the blow hits, there will be no chance for centuries to lower atmospheric levels of carbon dioxide, given how slowly oceans absorb it.

Scientific experts cannot say just when higher greenhouse gas emissions will take us past irreversible tipping points in the climate system. Nor can they predict whether change will come in manageable increments over centuries, or will happen suddenly – within decades or even years. Earth’s climate could “jump rapidly in the future,” Alley says, and has done so in the past. The possibility of abrupt climate change – particularly given the unexpectedly rapid melting of the Greenland and West Antarctic ice sheets – has researchers “very worried,” he says, and makes worse-case scenarios more likely: “The uncertainty is mostly on the bad side.”

Faced with increasingly dire warnings about a warmer and more volatile world, many states and cities are not waiting around for national and international action. Boston and seacoast New Hampshire are at the forefront of this trend. New Hampshire has a Coastal Adaptation Workgroup, an annual Climate Summit, and a Climate Action Plan that state agencies have for five years been working systematically to implement. A recent New Hampshire report on climate impacts echoes the dire tone of the AAAS and U.N. papers. Massachusetts Gov. Deval Patrick recently announced a $50 million climate preparedness plan, and women around Boston are taking climate action under the banner Mothers Out Front.

Maine started down this path in 2009, completing two initial climate change reports, but Gov. Paul LePage vetoed a bill last summer that would have helped Maine agencies begin to implement climate preparedness (and the Legislature fell one vote short of a veto override). While pre-eminent climate scientists voice concern about the “risk of abrupt, unpredictable and potentially irreversible changes,” Maine’s governor extols the potential economic gains that await us from the arctic melting that has opened Canada’s Northwest Passage. This Pollyanna stance appears painfully naive in the face of the AAAS consensus that things are “very likely to get worse.”

The LePage administration focuses on the potential “benefits” to Maine agriculture that a longer growing season will bring. Farmers – already contending with more climate variability – aren’t joining this “Glad Game,” celebrating the positive side effects of a planetary fever. We’re seeing “hotter hots, drier dries and wetter wets,” meteorologist Lou McNally observed at a Common Ground Country Fair panel in 2011. “Climate change is here,” says Aroostook County farmer Jim Gerritsen. “If you don’t believe it, talk to a farmer – we’ve been experiencing it for 10 years.” And each year brings more unwelcome surprises, like the arrival of unprecedented pests.

Farmers and scientists recognize that the risks posed by climate change are not centuries off, falling on anonymous future generations. They’re here now, and getting bigger daily. Our lives, and our children’s lives, could take a serious turn for the worse in coming decades.

In “What We Know,” the AAAS scientists hold out hope we can change sufficiently quickly to forestall catastrophe – as we did in the past addressing threats such as acid rain and the ozone hole. Whether we will change remains an open question.

Marina Schauffler, Ph.D., is a writer and environmental consultant who runs Natural Choices (www.naturalchoices.com). Her biweekly column, Sea Change, explores some of the profound cultural shifts needed to attain greater sustainability.