Up in the High Sierra of Yosemite National Park today, a monstrous wildfire is racing through 200 square miles of dense piney forest. The "Rim Fire" is only one of about fifty major wildfires across the American West today, but everyone has at least heard of the majestic Yosemite Valley with its glacier-carved Half Dome and summer traffic jams of vacationers seeking waterfalls and hamburgers, so this is our official Natural Disaster of the week.

Like the last 10 years of increasingly insane wildfire seasons, it is also a preview of what's coming for the western half of the country.

Devastation of forests and forest critters usually goes unmentioned in media damage reports, which always note the burning of "structures." Anyone familiar with the type of character who lives in the remote parts of the American West will agree that the loss of a single annoying chipmunk stealing Cheerios from a campground is more worthy of mourning than all the rural-residential-zoned stucco ranch houses and aluminum storage sheds full of off-road motorcycles combined.

But even wire-service reporters and local newspapers have started mentioning the environmental causes of these Hell Storms: They're fueled by a combination of persistent drought and pine-beetle infestations that kill off the thirsty trees, both consequences of hotter and drier "summers" that now stretch from March to December in much of the West. The biggest and hottest blazes, like the one at Yosemite today, are part of our new non-stop disaster weather, but they also create their own climates, including towering thunderstorms that build up over the burning forests and shoot daggers of lightning down to start new fires. Heat and wind combine into quick-moving cyclones that trap and kill firefighters and leap over fire lines, rivers and highways.

The Western forests are not recovering the way they should in the Smokey Bear interpretation of the fire cycle. The scorched earth is becoming arid and rocky, with new growth of scattered scrubby brush rather than shady nurseries of new pine and fir. When the unreliable winter storms do come, the downpour finds not a soft decomposing forest floor but a hard sandy surface that can't hold the water at all. Instead it barrels downward, like a desert flash flood, taking ever more organic stuff away, leaving nothing to recharge the mountain slopes, no soil and no shade. Just like clear cutting by the logging industry or the kind of desperate wood chopping that has left Haiti a deforested wasteland alongside the neighboring Dominican Republic's green national parks, the epic fires of America's 21st Century are turning primeval forest to desert.

Unless you can see the ash and smell the smoke, the hellfires can feel far away—until, suddenly, one's right on top of you. Californians are somewhat used to this, with regular infernos coming out of the canyons and into Los Feliz or Santa Barbara or Malibu. The Yosemite fire has even managed to menace a city 200 miles away. California Governor Jerry Brown declared a state of emergency for San Francisco and its surrounding sprawl of 7 million people, not because the actual flames threaten the Bay Area but because the Hetch Hetchy reservoir provides both drinking water and electricity to the metropolis. Power lines are already being consumed by the 130,000-acre inferno, which has come within a mile of the reservoir and is only 15 percent contained. If Hetch Hetchy fills with ash, San Francisco will get thirsty.

At the National Interagency Fire Center in Boise, the Fear Level is at its highest setting. The federal costs of firefighting over this hellish season have already topped $1 billion, particularly because big fires have hit "urban-wilderness interfaces" favored by the West's conservative and libertarian types who enjoy the isolation from a human community while still demanding a nearby infrastructure of highways, water lines, Costco, Internet service, Social Security offices and medical centers. Chipmunks just burn up and die; the Western individualist expects an "air tanker" to save his 3,500-square-foot fake log cabin at the first sniff of trouble. The fires that destroyed nearly a thousand houses in semi-rural developments in Colorado's forests this summer have already cost insurance companies nearly $800 million, while the U.S. government's firefighting budget for the year is already gone, with another several months of the lengthening fire season to go.

The point will soon come, like it has in Detroit, when the various authorities will look at the huge impossible area they're supposed to protect and decide instead to retreat. Lines will be drawn around the forests that are too dangerous for fire-fighting, whether they're in a housing tract tucked into the Montana wilderness or a winding road of mansions in a Malibu canyon, and the people living there will get a notice from the insurance company saying the wildfire policy is cancelled. The TV news will show heartbreaking footage of a middle-aged man in a cowboy hat who refused to leave, out there in a giant fuel box of trees killed by the pine beetles.

The mountainous West can then open for disaster tourism, a chance for the fortunate to see what's coming for all of us, soon, as the forests that hold the rainwater give way to Mojave Desert scenes of burnt rock and dry creeks. Walking a desert slope in August, it's easy to see the Earth going the way of Mars. No water, no life. No plants, no oxygen. No shade from that sinister faraway star, and no atmosphere to hold in the warmth when your part of the planet turns its face to the cold void of space every night. When the forests burn up for good, the land can't hold water. When there's no easy way to get fresh water for 7+ billion people, the number of people will begin to rapidly decline. Your personal financial situation and the luck of geography will define whether you're one of the few who survives these calamities.

Summer is not a celebration. It's an annual warning.

Ken Layne's American Journal appears here on Mondays. Remain vigilant.