How to write about climate change and convey in the words and sentences the abiding urgency of what is now an irrefutable existential threat? I’m not sure. I do know that in the midst of all the sturm und drang of our politics it is never far from my thoughts.

In a recent article in the New York Times Magazine, Jon Mooallem wrote, “How do we live with the fact that the world we knew is going and is, in some cases, already gone? The future we’ve been warned about is beginning to saturate the present. We tend to imagine climate change as a destroyer. But it also traffics in disruption, disarray; increasingly frequent and more powerful storms and droughts; heightened flooding; expanded ranges of pests, turning forests into fuel for wildfires; stretches of inhospitable heat.” He points to the mass starvation in South Sudan where nearly a million and a half children are predicted to die this year. The cause: an unforgiving and continuing drought.

How to respond? We observe extreme weather globally, and we understand, intellectually, that these are not black swan events. Strangely, we can know while still not knowing.

Climate change is an unparalleled threat; yet, it doesn’t register as such.

How to read and react to a recent study published in the Proceedings of the National Academy of Science that had as its lede, “Biological Annihilation is Underway.” Thousands of animal species — from common barn swallows to exotic giraffes to African lions — are in precipitous decline, a sign that an “irreversible era of mass extinction is underway.” The authors estimate that about 30 percent of all land vertebrates exist on a precipice, calling it a “global epidemic,” caused in great part by the human destruction of animal habitat. Dr. Paul Ehrlich, a member of the study committee, stated, starkly, “We’re toxifying the entire planet.”

Actually, our own Defense Department agrees and refers to climate change as a “geopolitical threat multiplier.”

So once again the question posed is: how to explain our seeming inability to react in ways commensurate with the threat that confronts us?

Of course, the climate change deniers are ever with us. Donald Trump stood in the White House Rose Garden and, as if planting a flag on the summit of Everest, withdrew from the 2015 Paris Climate Accord, abdicating America’s commitment to reduce our greenhouse gas emissions by 26 to 28 percent by 2025. We know that 153 nations have ratified the accord, the intention being to limit the rise in atmospheric temperature by 2 degrees Celsius above preindustrial levels.

How did such an act by the president escape our outrage and protest? Why was our reaction to this withdrawal so tepid? Met with little or no opposition from the Congress or the nation, Trump gave executive orders instructing Scott Pruitt of the EPA and Ryan Zinke at the Interior Department to delay, diminish or eliminate entirely those environmental policies meant to support clean water and clean air and open habitat (the Antiquities Act).

Trump has gone on to give his support to what are in truth dying industries such as coal, oil and natural gas, all major producers of CO². He has ignored any attempt to ramp up any research and development of renewables like wind and solar.

Mooallem, searching for an explanation for our passive reaction to global warming policy, writes, “We insulate ourselves from disorientation and alarm ... We seem able to normalize catastrophes as we absorb them, a phenomenon that Peter Kahn, a University of Washington professor of psychology, calls ‘environmental generational amnesia.’ ”

According to Kahn, each generation can recognize only the ecological changes its members witness during their lifetimes. People are born into this life and they think its normal. University of British Colombia Daniel Pauly calls it “impairment vision.” Or the “shifting baseline syndrome.”

They speculate that most of us are not indifferent to global warming but merely inhabitants of our moment on the planet. We adapt. Beijing residents wear masks. What came before is not of our world. What is ahead is hypothetical. Now is our new normal and the inherent contradiction can seem jarring.

— Chris Honoré of Ashland is a Daily Tidings columnist.