After a recent conversation with a self-described “climate agnostic,” I found myself trying to articulate why that was not a tenable stance. I wrote that person, whom I will call Jane here, a letter. I am sharing it beyond the intended recipient – knowing that many of us today are struggling to bridge ideological chasms. Political beliefs will shape how we respond to challenges but must not dictate what constitutes our shared reality.

Dear Jane,

In our recent talk about climate change, you reiterated that you’re “not a scientist” and want to “keep an open mind.”

An open mind can be helpful when untangling the truth from conflicting accounts. I know you are frustrated trying to sort out credible sources of information. (Some guidelines at the end of this letter may help.)

Clear evidence, though, warrants a different stance. “The solid world exists, its laws do not change,” George Orwell observed: “Stones are hard, water is wet, objects unsupported fall toward the earth’s center.” We all live our lives by accepted scientific truths.

You trusted the expertise of medical doctors when diagnosed – many years ago – with cancer. You were not a scientist capable of analyzing oncological data, but you did not keep an open mind about a life-threatening tumor.

Opting for treatment based on empirical science was a sound decision, one proven by time. Your older son, a scientist himself, works every day to ensure that his patients have similarly good outcomes – based on the best available data.

Imagine that his scientific career had taken a different trajectory and he’d become a glaciologist, like the French researcher Claude Lorius who appears in the new film “Antarctica: Ice and Sky.” It portrays field research in the most unforgiving place on Earth, with mean temperatures around -60 degrees F compounded by high winds and drifting snow. Lorius, now in his 80s, recounts how his 22 polar expeditions were marked by extreme hardships and risks. Yet his accounts of fear, exhaustion, setbacks and 45-degree F “cabins smelling of wet socks, instant soup and exhaust fumes” are leavened by irrepressible passion – what he calls “my wild empathy for the planet.”

That devotion to discovery is surely one of the most inspiring qualities of our all-too-fallible species.

I found the film especially poignant because last fall a field accident in Antarctica claimed the life of Gordon Hamilton, a renowned glaciologist beloved here in his adopted state of Maine. He was 50 years old, just your son’s age.

Hamilton died in a treacherous area where ice shelves meet and crevices abound. Glaciological research has become more perilous in recent years because climate change has made ice sheets more dynamic, with faster surface and submarine melting.

Climate scientists continue their studies despite the dangers because their research reveals such alarming trends. A crack in Antarctica’s Larsen C Ice Shelf, for example, is growing in length by about five football fields a day.

The painstaking research done over decades by scientists like Lorius and Hamilton helped supply the data for that hockey stick graph you asked about, which depicts the sharp rise in global mean temperatures since the Industrial Revolution. Glaciological research established the clear link between atmospheric warming and human activity, tracing climate history through the composition of air bubbles trapped in ice-core samples.

Thousands of scientists in various branches and disciplines, working on every continent with peers reviewing their findings, produced the current consensus on climate change. The same exacting protocol governs medical research, generating recommendations like the one you staked your life on.

So why does this particular scientific consensus on climate provoke such vehement reactions? Thoughtful, highly skilled researchers – trying to use their expertise for the common good – have been subjected to hate-filled e-mails, death threats, hacking and legal harassment.

Clearly, evidence of a warming planet threatens entrenched economic interests. We can’t keep fueling the world on gas, oil and coal if we seek to sustain a livable planet. It’s that simple and that hard.

Industries threatened by the transition to renewable energy have leveled attacks on climate science and manufactured public uncertainty (using tactics like those of the tobacco industry). Another movie (and book), “Merchants of Doubt,” depicts this history in detail. It’s worth noting that the evidence of climate science is now as clear as the link between tobacco use and cancer.

Fossil fuel interests have a strong grip on the new presidential administration, so expect to see much more climate misinformation (or, in its parlance, “alternative facts”). The new Cabinet has already begun suppressing the work of scientists and removing climate change information from government websites, a tactic that should scare all of us who value policies based on evidence rather than ideology.

I do hope that you will watch “Antarctica: Ice and Sky” and reflect on the role that science has played in improving (even saving) your life. Climate scientists have devoted their lives to eye-opening and mind-changing research. The least we can do is heed the evidence and act.

Marina Schauffler is a writer whose work is online at www.naturalchoices.com.