Articles like this bring deniers out of the woodwork, and I don't think it's representative overall. They continue to believe falsehoods and misrepresentations. The idea that the world is too big for us puny humans to impact is a constant that environmentalists always had to deal with. Early on, they said the atmosphere was too big for our air pollution to impact. Same for big rivers and lakes. Now it's the climate.

But getting beyond that, it is important to consider what the NPS' role is for a situation as broad and deep as this. The NPS shouldn't 't take on the role of much larger agencies with an explicit role in policy and/or regulation. But I think that education as to the impact could be it's most important role. Our national parks may be the locale where the most people get the closest to the natural environment. Park bookstores and visitor centers need to rigorously stick to the most well-settled science, even though the kinds of deniers who are responding here will be upset with it.

Ranger talks shouldn't shy from dealing with this issue, even though they will get snide comments from some visitors. Though some readers may have a fit about it, those aspects of the issue where the consensus is strong (see http://en.wikipedia.org/wiki/Consensus_on_climate_change_controversy) should be well-covered and get the focus.

As well, efforts to help species whose range is being eliminated and where park borders prevent migration could be helped. but not to the degree that we make zoos out of the parks.

I neglected this articles as well, on the current consensus.

http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change

I know the Anonymouses are piling up here, but I'm the original, and I think Dean is exactly right. Not right that I'm a denier who believes falsehoods and misrepresentations--anyone who claims that there is such a thing as "settled" science is trying to cover up contradictory evidence through an appeal to authority. There was a time when Newtonian mechanics was the last word in physics...

Rather, Dean is right that we have agencies for environmental policy, and the NPS would gain nothing and lose much by trying to become another EPA. (Or, to get back to the point of Kurt's original post, the NPCA will gain nothing by turning NPS into another EPA.) If there is a role for the NPS in climate change, it is in educating about effects.

1. By talking about effects, we work from empirical evidence, rather than theory. Changes in glaciation, plant and animal distribution, rock geology, air quality--these can all be measured and reported on the local level. Their causes are almost never singular. Let's take an example: wildfire. Increased wildfire rates can be attributed to hotter weather, drier weather, insect infestation, misguided fire suppression policies, and increased human carelessness. In many cases, most or all of these are factors. To global-warming zealots, the main cause is global warming. To the timber industry, you can be sure the main cause is bad forest management. Who is right? In the macro sense, they both are. But to each group, every fire is grist for their respective mills. It is wrong for the NPS, or its representatives, to single out a pet cause and use the parks as a pulpit for policy evangelism. But the evangelists can never see that (I'm looking at you, climate zealots!), because they're right, dammit, and why can't everyone else see that?

2. The parks are discrete areas, with discrete interpretive missions. It is entirely preferable to discuss (for example) receding glaciers in the context of local changes in temperature and precipitation without needing to talk about temperature and precipitation changes on the global scale. We oversimplify the global climate system when we attribute local changes in glaciation to worldwide effects. And we stray far from our appointed topics. If anything, use climate change as a springboard to talk about Glacier NP, but don't use Glacier NP as a springboard to talk about global warming.

3. Ultimately, educating about effects and their potential causes, without taking policy positions (like NPCA's ridiculous and disastrous cap-and-trade system) based on our personal bêtes noire, is good interpretation. These are complex systems. I do not expect any visitor to gain a mastery of climate science by reading a series of wayside signs. I do not want anyone to come to a conclusion about global warming based off my, or any other interpreter's, 20-minute talk about glaciation. What we can do is introduce the idea that these matters are extremely complex, and that they should be skeptical of anyone who tries to sell them a policy proposal based on a 90-second thumbnail sketch of climate science, either for or against.

Forget the ants, they are part of the cycle that is going on for millennia. Co2 in the biosphere is natural and the ecosystems and the global greenhouse is well adopted to it. The problem arises because we pull carbon dioxide from deposits were it was stored for millions of years and sequestered from the biosphere and release it by burning fossil fuels such as coal and oil.

This carbon dioxide is additional to the amount that the biosphere and the meteorological system is adopted to. And only a fool can think that this won't have consequences. It is this easy. Anyone who does not agree is either a fool or has a personal agenda.

I really wanted an answer to my question: What do the naysayers think happens to the planet when we put so much carbon into the atmosphere?

If there is a question as to what happens to all that carbon, perhaps the precautionary principle is the best way to treat the over abundance of carbon created by mans actions. Unless you don't care.

I'm afraid the comments section of National Parks Traveler is, if anything, a less suitable place to get into intricacies of climate dynamics than an NPS visitor center. And it strays far from the original point of the post and the comment thread.

But since you insist on an answer, Richard, I respond that your question is invalid. (This is the correct answer to a lot of life's questions--ask a philosopher!) You seek a simple answer to a question that defies simple answers.

Let's re-phrase the question: You want to know whether an increased proportion of carbon molecules in the atmosphere will cause the planet's aggregate average temperature to A.) Increase, or B.) Decrease. What this question fails to recognize is that there is an unfathomable number of constants and variables affecting that equation. Many, if not most, of those constants and variables are debatable, unknown, or unknowable. Some cannot be measured with any technique we have. Some, we measure entirely wrong. Of some, we are entirely unaware. Some act in completely screwy ways that we don't understand. Many affect each other in real time. Many have effects that don't manifest for years or decades. Most are of infinitesimally small effect.

In concrete terms, those variables include the entire global atmosphere, all liquid, gaseous, and frozen water on Earth, a wide variety of geological factors, every living thing, including rainforests, ants, and humans, the position and mass of the Moon, and any and all solar activity, or lack thereof. We know that the Earth's climate has varied in the past--this is not an insignificant point. So whatever the role of greenhouse gases, we know that some of these other variables can have an impact far larger than anything we have actually observed from CO2.

This is why it is fabulously difficult to solve for the effect of carbon gases on global temperature. And that's assuming that the desired solution is itself a valid [url http://www.sciencedaily.com/releases/2007/03/070315101129.htm]concept[/url].

Then there is the matter of feedback loops. All catastrophic climate change predictions depend on the idea that small amounts of warming will themselves cause larger amounts of warming. (This is reflected in Ray Bane's comment, and every claim that it is already, or may soon be, "too late.") This goes beyond the complexity of the original equation, and requires a shocking amount of voodoo and guesswork, to come to a conclusion that is wholly counterintuitive. In the macro view, the physical history of these systems shows that in the most recent few millions of years, the Earth has been fairly steady. An Ice Age here, a great drought there; these things are normal, and do not lead to catastrophic, cascading changes. Yes, massive glaciation across the upper Midwest would be terribly inconvenient, but it's happened before, and life went on. It is the very existence of life, in all its glorious variety, which illustrates that the earth's climate, as a whole, possesses positive dynamic stability.

That is, when something like CO2 concentration gets out of whack, the system as a whole compensates. It's not a conscious thing; rather, the system can exist only because it compensates. Otherwise, it would have spun out of control eons ago, and would never have attained the stability necessary for millions of years of evolution. A simple and familiar illustration of positive dynamic stability would be vegetal processing of CO2. If increased CO2 concentrations (natural or anthropogenic) warmed the Earth's climate, one important result would be an increase in vegetation, as ranges and growing seasons expanded. Greater plant growth would consume more CO2 and sequester it in solid organic matter, leading eventually to a reversion to the mean--less atmospheric CO2, cooler weather, decreased range, less plants. This is merely an example to illustrate the concept, though I stress that this interaction is described by the same great equation that we previously arranged to solve for global average temperature. It has just as many constants and variables, and is just as difficult to test.

Did anyone bother reading all that? Now would be a good time to mention that I gave up on my scientific career goals somewhere around 10th grade, when I figured out that my chemistry teacher was a schmuck, and that I sucked at math. But I was around long enough to learn that science is about debate, not consensus. (Would now be a good time to talk about eugenics, and how nasty things can become when scientists convince politicians that they've figured it all out?) Instead, I'm just a historian. A historian with enough career ambition not to put his name on comments that, I hope, have been reasonable and insightful, but that are contrary to the prevailing political and organizational winds.

Now, here's what I want out of this. I don't want to convince anyone that I know everything, or anything, about climate science. I don't want to convince anyone that global warming is a myth or a hoax; I don't have the scientific moxy to do it. But I do want every reader to stop caricaturing their political opponents! Each camp is made up of a range of people, including some on both sides who contribute nothing more than annoyed scoffs. There are enough evasions and logical fallacies bandied about by both sides to make Aristotle cry. But there are also people who know what they are talking about, and are debating in good faith. Let each reader consider: If you brush these people and their arguments aside, you are no more than a scoffer, and you are not part of the debate--you have picked your team based on the color of their uniforms.

If you want to seriously consider skepticism about climate change, rather than dismissing it summarily because of the color of its uniform, I can certainly recommend starting with Warren Meyer's blog, www.climate-skeptic.com . He's serious, skeptical, and debates in good faith.

Of course, there are large uncertainties involved in forcasting climate change. Climate change specialists work with uncertain data, alternative mathematical models, competing models, and full quantitative uncertainty analysis. Much of the details are documented in the numerous technical reports of the Intergovernmental Panel on Climate Change (which few who have commented thus far on NPT seem to have taken the time to study).

The overall IPCC conclusion, with 90% certainty, is that the present trends in climate change is being caused by anthorpogenically enhanced levels of greehouse gases.

Here is a link to an extensive 2007 technical summary from the IPCC on the physical science basis for their conclusions that it is highly likely, even when accounting for all known sources of uncertainty in data and models, that the present increases in global warming are anthropogenic (i.e., not from sun spots or from insect gases).

http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-ts.pdf

It seems to me that one of the first steps of human-assisted climate change deniers is to lable the IPCC as a "political" rather than a scientific organization. This to me is an easy tactic used to debunk the concern and to argue against the commitment of any societal resources to combat global warming. The global warming deniers recognize that few individuals have the time or patience to digest the scientific literature to independently evaluate the overall merit of the scientific argument. However, when such an independent service is provided by the IPCC, it's simply attacked as being without appropriate credentials.

Now with regards to our national parks, I believe that it is perfectly appropriate for the NPS to become engaged in public awareness education about real and potential threats to park resources and to the park experience. What is delivered in official programs, however, should always have a basis in scientific fact. Public education about the potential impact of global climate change on our parks is a legitimate NPS function. Pubic education about other potential threats is also appropriate.

Whether or not climate change is the single most important threat to our parks depends on one's overall perspective. It depends whether one's outlook extends only to the next park visit, to future visits over the next decade, or whether one is looking at the future of parks over the next 100 to 1000 years. A perspective over the next 10,000 to one million years will likely produce other priorities.

Owen Hoffman
Oak Ridge, TN 37830