It was a dress rehearsal in which everyone seemed to be wearing the wrong clothes.

London, Saturday, June 10: 1,400 British soldiers are practicing for an upcoming military parade near St. James Park. The ceremonial run-through, known as the Colonel’s Review, is its own spectacle and draws its own crowds and camera crews. Some soldiers are on horseback, and some play in bands. All are arrayed in precise columns and lines.

The Massed Bands of the Household Division perform a march. They wear the familiar costume: red woolen tunics, dark woolen pants and those towering, ovular, poofy fur hats that the Household Division has worn for more than 200 years. The hats are called bearskins. They are made from the fur of a black bear. Each is 18 inches high and weighs one and a half pounds.

You know the Household Division. They are the stately human chess pieces guarding London’s royal palaces whom you can watch online, refusing to smile, as vacationing YouTubers pelt them with wisecracks at close range. What these soldiers do best is endure. They withstand. But that morning, London is on its way to a high of 84 degrees — 13 degrees hotter than the average high for this time of year — and the soldiers, in their thick, cumbersome hats, are performing in a shadeless gravel lot.

A trombonist goes down. One moment, he’s blaring away at the front, and the next he has fainted, prone at the others’ feet, like a crumpled bill left in front of some buskers. These soldiers are actually trained to “faint at attention” — to faint, if they must faint, with fortitude and resolve, without reaching for anything as they topple, simply falling forward like a proud, insentient tree. When the BBC camera finds the trombonist, he is on his side but still has his instrument held to his lips, his hands adhered to the horn in perfect playing position, while behind him, his colleagues play on.

Four officials in dark uniforms come to retrieve him, like stagehands fetching scenery. They carry a green military stretcher, but by the time they arrive, the trombonist is upright again. He has hoisted himself to standing by mashing the tip of his trombone’s slide into the dirt. Then, having staggered back into line, he raises the instrument to his mouth. He is joggled, woozy, but committed to expelling whatever air he’s got in his lungs into the horn, exchanging life force for music.

The stretcher people do not let him do this. They take his trombone away and walk him offscreen. But what you might have missed — what I missed the first time I watched this clip online — was that, as they scampered toward him, they momentarily crossed paths with a second group of attendants scurrying off the field. These people were also carrying a stretcher. And on their stretcher was a clarinetist. According to a news report, there were three musicians who fainted during the rehearsal — three, “at least.”

These men have names. They have identities. They have loved ones and favorite foods and dreams. I feel for them. Fainting is scary and terrible, and I feel conflicted about writing about the incident from inside my climate-​controlled home.

Still, they were uniformed soldiers who volunteered to be symbols of something larger than themselves. And now, they had become symbols of something different too. We may talk of “battling” climate change, but here were actual soldiers being knocked to the ground.

This problem of overheating soldiers has arisen before. Last July, during the hottest month of the hottest year on record in England, a heat wave thrust the temperature in London to 104 degrees Fahrenheit, more than 30 degrees beyond the average high.

Airport runways and roads buckled, as did train tracks, complicating travel. (It was roughly 10 degrees hotter than the peak temperature at which Britain’s rail system was designed to function.) Computer servers couldn’t be cooled sufficiently, crashing the systems at two different hospitals; surgeries were canceled, patients turned away. Fires broke out around the city and, in a place where fewer than 5 percent of households are estimated to have air-conditioning, 664 people died.

The Household Division guards, meanwhile, roasted outside Buckingham Palace. One afternoon, the AP photographer Matt Dunham captured a regular security guard (Kevlar vest, utility belt, cuffs) pouring a drink of water into one of these soldiers’ mouths. (Drinking is prohibited while on duty.) It was a staggering image, as if a time traveler had been sent to intervene in Elizabethan times with the technology of bottled water. A dam of superhuman decorum was cracking; the heat was that unbearable. Even so, the costumed guard refused to break his posture any more than necessary. He accepted the drink with his arms locked at his sides, his bayonet-tipped rifle still propped at his clavicle. And when he tilted his head back, he did so only a few degrees, the minimum necessary for the liquid to slide inside.

Is the job now to defend our lifestyles against the climate? Or is it to reinvent them?

What does climate change feel like, really? The core of the experience may be a sense of dislocation, of being newly and scarily mismatched to the world. It’s as if everything around us, everything we rely on, has been transported to a different place than the one it was designed for — a harsher, meaner Earth.

On Mean Earth, all kinds of previously durable infrastructure can be undermined or undone. This includes train tracks and computer servers, but also cultural infrastructure: the unexamined things we do a certain way because we’ve always done them this way, that’s why. Consequently, the predicament of that trombonist in his woolen clothes feels increasingly familiar. Kids sent to sleepaway camps where it’s too hot, or too smoky, to do much outdoors; vacationers on beaches littered with dead fish after a colossal algae bloom; homeowners rebuilding after their second wildfire or flood — all are re-enacting rituals that are slipping out of phase with their environments and thus being drained of their joy and logic.

That frenetic scene at the British parade — the uniforms, the stretchers, the scurrying, the chaos, the dignified persistence of everyone to face forward and persevere — reminded me of a war movie, with medics speedily extracting the wounded from trenches during an assault. Prince William later issued a statement which framed the incident in just that way: “Difficult conditions but you all did a really good job.” His men had withstood the attack.

But is the job now to defend our lifestyles against the climate? Or is it to reinvent them? Undoubtedly both, though we seem stubbornly predisposed to the first approach — soldiering on in our old, wrong clothes. While the clip of that fainting trombonist brings to mind all the admirable bromides about grit and resilience, it also made me think of Einstein’s remark that doing the same thing over and over again and expecting a different result is the definition of insanity. And there’s a much less lofty, more common-sensical way of thinking about it too: If it’s hot out, take off your giant fur hat.

All of us may find ourselves clinging to habits that, here on Mean Earth, are losing their usefulness and power. But imagine what it would feel like: the weight of the bearskin lifting, the heat beginning to vent freely from the dome of the head. It would still be hot — abominably hot — but at least you’d be standing unencumbered in this world, as it is.

Opening illustration: Screen grabs from YouTube