Jon Reiter, the Kenwood contractor who was caught by an avalanche in the Khumbu Icefall on his second attempt to summit Mt. Everest, is coming home. His wife, Susan, blogged Wednesday morning that Reiter was flying by helicopter to the Lukla airstrip on Thursday, the one landing site for fixed wing aircraft in the Khumbu region. From there it is a short flight to the Nepalese capital of Kathmandu.Reiter’s return may be a modest personal disappointment in the overwhelming tragedy that took 16 lives and appears to have brought the Everest season to a halt, at least for all but the most seasoned and self-sufficient independent climbers.But it is also a sobering reminder that the route to the roof of the world has begun to be taken for granted as increasing throngs of well-heeled, high-altitude tourists crowd terrain that is inherently dangerous, unstable and inevitably deadly.For close to two months, I lived at the base of the Khumbu icefall, on the eponymous glacier that was literally melting away beneath my tent. As a journalist covering a major Everest expedition I had reason to see for myself, close-up, the fractured terrain at my front door. But as a decidedly amateur climber and admirer of nature’s grandeur, I could no more have ignored the call of the icefall than pass through the Louvre without looking at the Mona Lisa.Basically a frozen waterfall dropping 1,500 feet over the course of a mile-and-a-half, the icefall moves about four feet a day, and it doesn’t do it quietly. It creaks and groans and pops and explodes, those motion sounds periodically punctuated by the thunderous crack of an avalanche dropping off opposing walls ladened with hanging cornices the size of boxcars.Aesthetically it is a wonderland of ice, tortured under stupendous pressure into every conceivable shape, with giant seracs and bottomless crevasses on a scale that dwarfs anything human.Somehow, in 1953, the British Mount Everest Expedition pushed a path through that tangle of shifting ice, without the benefit of aluminum ladders, allowing Tenzing Norgay and Sir Edmund Hillary to reach the summit.Since then some 250 people have died climbing Everest and on the growing list there are now 16 new names, all Sherpas. That recent toll reconfirms the icefall as the most dangerous section of the Everest climb, in part because, as veteran Jackson Hole climbing leader Jim Williams once told me, “It’s not really about skill. If a block of ice the size of a football field falls on you, there’s not much you can do about it.”Increasing the level of risk, it must be noted, are two relatively recent developments. Looking at the talus slopes framing the western edge of the Khumbu Glacier above base camp, you can see hundreds of feet of naked scree once cloaked by the glacier, which has been ablating (shrinking) steadily as global temperatures rise. It is hard to believe that a warming environment is not increasing the instability of the icefall.And simultaneously, the flood of humanity crowding up the mountain almost ensures that when disaster inevitably strikes, the consequences will be increasingly harsh.Jon Reiter is a serious mountaineer, not a dilettante, but without Sherpa guides at close hand, he might now be dead. He has also been careful to point out that crowding was not an issue during the tragic collapse of that wall of snow and ice – there was not a bottleneck of climbers trapped by their sheer numbers.But with base camp now the world’s highest village, complete with WiFi, many other comforts of home and a population that sometimes exceeds 500, the question remains – has the carrying capacity of the world’s highest mountain been exceeded?And perhaps of greater importance, are the powers governing the presence of all those adventurers appropriately valuing the lives and the welfare of the Sherpa people on whom the entire Everest enterprise continues to rest?