Winter's fury is artistic mastery in Yellowstone National Park.

Arctic expresses that bolt out of the north sculpt shields of ice around some geysers, while bearding bison in rime. Trees bow down, weighted by overcoats of snow and ice, while drifts cause elk to flounder in their flight from wolves. Waterfowl cluster in the waning ice-free stretches of streams. No matter what the weather, the feathery upper and lower falls of the Yellowstone River captivate those who manage to reach the rim of their canyon.

This setting -- the sharp, biting cold, the clear night skies that can reverberate under the Northern Lights, the steaming geyser basins with the ever-present wildlife, the snow draping the eves of the Old Faithful Inn like so much vanilla frosting -- is what lures visitors to Yellowstone at the height of its harshest season. And yet for park managers, how to cater to those visitors continues to be a conundrum in the world's first national park, a place that begs both protection and display, reverence and celebration.

With winter now beginning to blow its cold smoke down across the Northern Rockies, the staff at Yellowstone National Park is embarking on its second decade of trying to figure out how best to welcome the public during an unforgiving season without greatly impacting the park. This has been neither a simple nor an inexpensive endeavor. With work now under way on a fourth environmental impact study weighing the pros and cons of snowmobiles versus snowcoaches, of nature's rattling of leaves and babbling of streams versus throttling of engines, of wildlife desperate to preserve calories versus visitors anxious to frame bison in their viewfinders, the cost of reaching an acceptable answer has surpassed $11 million. And there is no limit in sight.

While that fourth impact study is compiled, for the next two winters the park will operate under a temporary winter-use plan that holds snowmobiles entries to no more than 318 a day and snowcoach entries at 78 per day. In late October, the Billings Gazette editorialized about the matter, and encouraged "the Obama administration to pursue an ecologically sound plan for winter use, a plan based on solid, up-to-date scientific research that allows the public reasonable access to the wonderland that is Yellowstone in winter."

Granting the newspaper's request might not be as easy as it sounds.

While all previous winter-use studies in Yellowstone have agreed that snowcoaches are the environmentally preferred alternative for winter travel, adopting a regulation to that effect is not easy, as the political fingerprints that have smudged this process tell. Plus, park officials now say evolving science and mechanics have placed snowmobiles and snowcoaches largely on par in terms of pollution. Scattered throughout the debate are issues tied to wildlife resources, noise, air pollution, and even access. That last issue perhaps is thorniest, as it revolves around your choice of travel in winter. Few people like to be told what they have to do.

But access in terms of simply being allowed into the park really doesn't appear to be an issue at this point. Throughout the winter you can drive from Gardiner, Montana, through the mammoth stone arch of the North Entrance to Mammoth Hot Springs, and then all the way east through the wildlife-rich Lamar Valley to the tiny village of Cooke City, Montana. Through the West Entrance at West Yellowstone, the South Entrance to the north of Jackson, Wyoming, and the East Entrance to the west of Cody, Wyoming, you can snowmobile into the park, with snowcoach options available through the West and South entrances. Last winter, more than 42,300 people found their way into the park via snowcoach or snowmobile alone. It's a tiny fraction of the 3 million or more who visit throughout the year, but a goodly number when you consider the lodges that are closed (those at Canyon, Tower-Roosevelt, Lake, and most of those at Old Faithful).

In the Billings Gazette's editorial, Yellowstone spokesman Al Nash was quoted as saying that under the temporary winter-use plan "this will be the first time that we will see daily (snowmobile) numbers reach the daily limit and more demand than the daily limit will allow." In clarifying his comment for the Traveler, Mr. Nash said he wasn't bemoaning the prospect of not being able to welcome more than 318 snowmobiles into the park per day. Rather, he said, he simply was stating that the entrance gates might come down before snowmobile 319 can enter.

"During the five years of managed, limited use, whatever the number has been, we have never reached the daily limit," the park spokesman said. "That makes the prospect for this year different, that we have an expectation that there will be more demand for access on some days than the interim regulation will allow. It is a different circumstance than we have had before.”

Whether the gateway communities that rely heavily on winter visitation to Yellowstone to support their economies during the cold, snowy months of December-March will notice if that cap is reached remains to be seen. During Fiscal 2009, the town of West Yellowstone, Montana, the self-proclaimed "snowmobile capital of the world," saw resort tax collections dip just one-half percent from FY 2008 collections, which, by the way, were up more than 12 percent from FY 2007, according to a story in the West Yellowstone News. East of Yellowstone in Cody, a gateway community that sits 53 miles east of the park, officials have been beaming about their winter tourism.

“Winter was once considered the quiet season in Cody, but in the past few years we have seen a dramatic increase in the number of visitors who travel here to participate in their winter activity of choice,” Claudia Wade, executive director of the Park County Travel Council, was quoted as saying in an October 30 article in The Big Sky Weekly. “The stores along Sheridan Avenue – our main street – are already stocking crampons, thermal socks and ski goggles, and our hotels report they are already taking reservations for the upcoming season. And when our visitors are ready to move indoors they will find a wide range of museums, galleries, restaurants and entertainment options.”

While the 318-snowmobile cap on how many snowmobiles can enter the park might be reached on a handful of days this coming winter, that doesn't translate into visitors being locked out of the park and shouldn't discourage winter travel to the park if your end-goal is to see Yellowstone and its wildlife under the harshest of conditions.

Last winter, when the daily limit was 720 snowmobiles, there were just six days out of the 90-day winter season when more than 318 snowmobiles entered Yellowstone. The heaviest traffic day was December 29, when 408 sleds entered the park. When you consider that those 408 sleds carried 208 passengers, some quick math demonstrates that those 616 visitors (408 drivers + 208 passengers) still could enter Yellowstone during this coming winter on the same day if they shared a snowmobile or hopped into a snowcoach, which have never come close to their upper limit.

More so, when you consider that 78 snowcoaches can enter the park each day, it's clear that access is not soon likely to be an issue in the park, even if the 318-sleds-per-day limit is reached. Based on last year's average of 8.5 passengers per snowcoach, if the park reached its upper limit of 78 snowcoaches a day, over the course of a 90-day season they would bring 59,670 visitors into the park, a number well above last year's 42,381 visitors who came on snowmobiles (23,418) and snowcoaches (18,963) combined.

Of course, what remains to be seen is whether there will even be demand for 318 snowmobiles per day. In recent years the park has averaged 205 snowmobiles per day, and just 29 snowcoaches.

No, if there's anything that likely will limit access to Yellowstone this winter and next it will be poor snow years, not snowmobile limits.