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NPCA Officials Cite Snowmobile Emissions In Criticizing Winter-Use Plan For Yellowstone National Park


Pointing to the National Park Service's own testing as evidence, National Parks Conservation Association officials are criticizing a proposed winter-use plan for Yellowstone National Park, saying testing shows snowmobiles have gotten dirtier and noiser, not cleaner and quieter.

In pointing to the park's Yellowstone Over-snow Vehicle Emission Tests – 2012: Preliminary Report, NPCA officials say the trend to dirtier and noiser snowmobiles the past six years "contradicts the snowmobile industry’s repeated promises to make cleaner snowmobiles and keep unhealthy gasses such as carbon monoxide, benzene and formaldehyde from fouling the air of the country’s oldest national park."

The report explains that scientists tested 2011-model snowmobiles in Yellowstone and compared their emissions with 2006 models made by the same companies, NPCA noted in a release.

"One manufacturer’s newer snowmobile emitted over 20 times more carbon monoxide than its earlier model. Another company’s newer model had higher emissions of every exhaust gas sampled, including 5 times more hydrocarbons," the release said.

The report concludes: “The model change in snowmobiles has not been a positive influence on air quality based on the emission data.”

In releasing the park's Draft Supplement Winter-Use Environmental Impact Statement earlier this month, Superintendent Dan Wenk said his proposal to allow up to 480 snowmobiles a day in Yellowstone, more than twice the average entries of recent winters, would make the park “cleaner and quieter.”

However, the National Park Service’s own studies contradict that assertion, the NPCA release said. "That document shows the proposed plan would increase snowmobile noise and pollution in Yellowstone National Park with significantly greater emissions of carbon monoxide and cancer-causing gasses such as formaldehyde and benzene," the park advocacy group said.

“Rewarding a technology that is going backward and getting dirtier is the very opposite of stewardship that Americans expect and deserve in Yellowstone National Park,” said Tom Kiernan, NPCA president. “After 10 years of pledging to make major improvements to emissions and noise, the snowmobile industry has gone back on its promise to the National Park Service and the public."

The emissions study looked at “recent additions to the snowcoach fleet” and concluded: “emissions are generally lower for newer snowcoaches compared to mean values of the earlier fleet and especially compared to the older carbureted engine snowcoaches.”

Indeed, specific data provided in the report show that current snowcoaches are up to 50 times cleaner than current models of “Best Available Technology” snowmobiles when the vehicles’ carbon monoxide emissions are calculated on a per-visitor basis. In per-visitor emissions of hydrocarbons and nitrogen oxides, the report shows snowcoaches are 2-5 times cleaner than snowmobiles. The report reflects that these air-quality advantages of snowcoaches are expected to become even more significant when Yellowstone requires all snowcoaches to utilize newer engines.

“The National Park Service should make an immediate U-turn on this misguided policy. After all, the growing majority of Yellowstone Park’s visitors prefer multi-passenger snow coaches, which are demonstrably cleaner than snowmobiles, which are getting dirtier. Even park officials have acknowledged that,” said Chuck Clusen, director of the National Park Project at the Natural Resources Defense Council. “The only obvious and responsible path forward is to facilitate the use of snow coaches, not snowmobiles.”


Wow a lot of discussion while I was gone.

Let me ask you two questions, YNP4everyone:

1) What would be wrong with minimizing to the greatest extent possible air quality impairments and noise levels, while also letting folks enjoy the park in winter?

2) Do you have a vested interest in snowmobiling in Yellowstone?

Fair enough on number one I believe we have reached that point as the studies show the air quality is a long ways from any alert levels in winter. As I had pointed out above that one of your studies linked above stated "The observed air quality is dependent on several meteorological conditions that dominate changes in the CO concentrations when there are just small changes in the snowmobile traffic." We have stabilized the emissions with BAT snowmobiles and with limiting the number of them. We can't control the weather which can raise the emissions from the same snowmobiles, far greater some days compared to other days although it is the same snowmobiles from the rental fleets. On the snowmobiles you can hear tracks turning and the skis sliding through the snow and the chains turning in the chain cases. How much quieter can you make them when you are now hearing sounds other than the engines? Others have already stated we have basically hit the point of diminishing returns in how much quieter or cleaner we make them, the studies won't show any quieter or cleaner environment due to mother nature and the meteorological conditions that the studies have noted. When you start limiting or eliminating the snowmobiles then you have taken away the ability of a certain group of visitors to enjoy Yellowstone which is opposite in I take it your view of wanting to be able to have folks visit Yellowstone.

Number 2 no I do not have a vested interest. I am a farmer who lives hundreds of miles away whos spare time is in winter and when I have the most free time to visit a great place like Yellowstone and I like to snowmobile.

I first snowmobiled in Yellowstone in Jan. 1998 when the issue first arose. It was chaos through the park with differing abilities and interests of what they wanted to do in the park. Today it no where resembles those past days. Today the guides take the time to lay down the rules and it is an orderly procession and they park out of the way for others. There are virtually always a person who has never been around a snowmobile before in the groups so experience varies greatly as well as their ability to stay orderly but the fact is they all came with a desire to see the beauty of Yellowstone.

Now I have a question or two for you about my observations in Yellowstone in the winter. On New Years day 2010 we rode the snowcoach to Old Faithful with an exchange student from Norway that we wanted to show the park to. When leaving Old Faithful just out on the road heading towards Madison Junction we met a vendor (I assume) on a 1976 John Deere Liquifire snowmobile pulling a sled. I know my snowmobiles and was amazed they could find parts to keep it running. My question is the studies all talk about the BAT snowmobile limits in the park but how many old 2 stroke snowmobiles are really still running in the park by concessionaires and by the park service staff? This John Deere would be about anti-clean as anything that could be allowed in the park with no fuel injection or oil injection. These would most likely pass the air quality monitors at West Yellowstone and at least in the area at Old Faithful. Maybe these types of sleds may be spiking the readings that you are blaming on the BAT sleds.

Also another day we rode snowmobiles to the Grand Canyon of Yellowstone. We saw some broken down rental sleds. When heading back out of the park we met some of the rental places coming in on two stroke snowmobiles to tow out the broken sleds. These were current 2 stroke models with fuel injection but these could also be raising the emissions levels as they pass the monitors at the West entrance.

Anyway just to let you know that there may be other reasons why the emissions levels vary in the park and there is a lot more than just BAT snowmobiles in the park so don't totally blame the visitors who are taking the time to enjoy on the BAT snowmobiles. That was three winters ago and not sure what they allow in the park now behind the scenes but still around the monitors. The same thing goes for the snowcoaches in how many of the older engine snowcoaches enter the park versus the newer technology snowcoaches on a given day which would fluctuate the numbers.

I have enjoyed the park both ways and see the need for both to exist in the park.

If I may offer another stark example of people's tradeoff behavior:

"There’s a well-known survey in sports, known as the Goldman Dilemma. [A] researcher . . . began asking elite athletes in the 1980s whether they would take a drug that guaranteed them a[n Olympic] gold medal but would also kill them within five years. More than half of the athletes said yes. When he repeated the survey biannually for the next decade, the results were always the same. About half of the athletes were quite ready to take the bargain."


Yes, half of Olympic-caliber athletes are willing to die within five years as a tradeoff for winning the gold medal! Life is (almost) all about tradeoffs, although there are some things that are sacred and may not be traded. An example is given by Steven Pinker in The Better Angels of Our Nature (2011), pages 638-639: "one may not sell one’s child for any other good." This, however, is an exception that helps makes the rule. Air pollution fits well within the rule, although obviously at a certain level of pollution the costs begin to exceed the benefits.

Rick B. writes: "The comment about 'no matter the cost or benefit,' is just editorializing, not objective."

I'm not quite sure what Rick B. means. If he means only that "reducing pollution is a [not] a 'bad' thing," of course that's right. If he means no amount is too much to spend on reducing it, that's not right, because that money could be allocated to better uses after a certain amount is spent on pollution control.

In other words, Anonymous is correct that the easiest fixes are done first, so "[g]etting rid of the first 50% [of pollution] may cost x. Get rid of the next 25% 10x. By the time we are getting down to the last 1%, the costs become astronomical."

This is Econ 101, and that's why I argue that people who care about the environment should learn economics (along with some engineering and some science).

One important aspect of economics is the calculation of tradeoffs. We calculate tradeoffs all the time. Some of them are shocking to people when laid out plainly. For example, we set the value of an individual human life at a certain amount and won't spend money to save an additional life beyond that amount. Were it otherwise, our highways would be built so that you could survive almost any accident. We don't do that because it would cost too much. It's better (more efficient and more life-saving) to spend that money on, perhaps, kidney dialysis machines or meat inspection. We don't have unlimited money and so we have to choose.

And more shocking yet, at a certain point there's a greater social utility to spending the money for things that don't save life at all. The government may legitimately decide, for example, that it's better (i.e., confers a greater social benefit) to equip itself with 10,000,000 computers than to save 500 lives.

And for similar reasons, we accept more than 30,000 traffic deaths a year on roads because we've decided that the social utility of being able to drive your own vehicle is worth that slaughter. The benefits of mobility exceed all the costs of 30,000 (or 60,000) traffic deaths.

In fact, as individuals we're always setting limits on the value of our own lives. A CAT scan increases our risk of cancer but we'd like to know if we have a kidney stone. Driving 70 is more dangerous than driving 55 but we'd like to get somewhere five minutes earlier.

I've written about mountain biking many times on these pages. Mountain biking is not cost-free. It annoys a certain number of people; it generates a degree of wear and tear on trails; it can put dust in the air; the fuel used to drive to trailheads adds to global warming. Mountain biking, like any activity, can be justified only if its benefits exceed those costs. I would argue that they do: improved physical and mental health; the generation of a lot of happiness for people who engage in it; increased knowledge about the land; support for conservation; etc. But if the social costs exceed the social benefits, then it should be banned (or people can mountain bike on private land).

Beat your wife? You joined this conversation which had a very clear discussion line. The debate from the beginning here has been the trade off of "pollution" reduction and its costs. I am sorry you aren't willing/able to follow through.

Strawman? Nonsense? The issue here is whether we should impose restrictions to reduce "pollution" that is already substantially below the standard. Do we reduce "pollution" just for the sake of reducing at any cost or do we balance cost and benefit.

I don't still beat my wife either, nor do I extend discussions with 'anonymous' posters.

we should spend anything it takes to get even the smallest decrease?

What strawman are you talking about here? This sounds like nonsense.

"no matter the cost or benefit" is just editorializing, not objective.

So Rick, you believe that we should spend anything it takes to get even the smallest decrease?

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