The Obama administration has endorsed these policies. Secretary of Transportation Ray LaHood and Secretary of Housing and Urban Development Shaun Donovan have agreed to require metropolitan areas to adopt compact-development policies or risk losing federal transportation and housing funds. LaHood has admitted that the goal of this program is to "coerce people out of their cars."

As such, compact-development policies represent a huge intrusion on private property rights, personal freedom, and mobility. They are also fraught with risks. Urban planners and economists are far from unanimous about whether such policies will reduce greenhouse gas emissions. Some even raise the possibility that compact city policies could increase emissions by increasing roadway congestion.

Such reductions are insignificant compared with the huge costs that compact development would impose on the nation. These costs include reduced worker productivity, less affordable housing, increased traffic congestion, higher taxes or reduced urban services, and higher consumer costs. Those who believe we must reduce carbon emissions should reject compact development as expensive, risky, and distracting from tools, such as carbon taxes, that can have greater, more immediate, and more easily monitored effects on greenhouse gas emissions.

In the blame game, the Obama administration isn't about to stop with Fox News. Instead, it's moving on to lowly scientists.

Last month, President Obama gave a somewhat chilling, if somewhat ignored, speech on climate change at the Massachusetts Institute of Technology. He stated that any scientific debate about the magnitude of global warming is unscrupulous, decrying "those who . . . make cynical claims that contradict the overwhelming scientific evidence when it comes to climate change, whose only purpose is to defeat or delay the change that we know is necessary."

Then, the president talked tough, saying, "We'll just have to deal with those people," language familiar to anyone who knows the vagaries of Chicago politics.

This surely isn't the first time in world history that some president, premier, or pope has attempted to define science and threaten those who disagree. But the truth of the matter is that disagreement, one way or another, is a given. One can selectively cite recent climate data in support of pretty much any point of view, from the rejection of any influence by humankind at all to the wild notion that the world is about to come to an end.

The ease with which anyone can construct just about any climate argument he wants has to do with the inconstant nature of climate itself. The sun warms the earth, but the amount of energy it radiates changes (right now it's pretty cold). The earth's surface is dominated by two very different substances — uneven rocks and large, smooth oceans — so internal climate oscillations and accidents happen as well.

Temperatures seesaw up and down depending upon ever-changing currents of air in the tropical atmosphere and oceans, including El Niño in the Pacific and other weather features elsewhere. They can be either cold or warm. When the warm ones are absent or weak for a decade or so — a common occurrence — temperatures may stay the same or even fall. When there's a huge warm phase in El Niño, global temperatures rise, as they did in 1998, setting records that have yet to be broken.

Finally, there's carbon dioxide itself. We put it in the air whenever we burn pretty much anything, be it in a power plant or in an automobile. Everything else being equal, that will warm temperatures at the surface and in the lower atmosphere. Just how much is the subject of a great scientific debate that has yet to be resolved.

And everything else is never equal. Cold portions of El Niño and a cold sun can completely halt carbon-dioxide–induced warming (and clearly have for more than ten years now). And this behavior creates a fertile environment for criticism of the projections of computer models for this century.

What you can say is happening to the climate depends on the period you choose to study. Using the surface-temperature record that scientists cite the most, you will find a significant cooling trend after 2000. You'll find no significant trend whatsoever if you start in any year between 1996 and 2000. Beginning your trend before 1996 will yield you significant warming. And so forth.

It's therefore not surprising that anyone can see anything on the climate Ouija board.

In fact, though, there's only one thing that is clear: For the last decade and a half, our climate has not behaved in accordance with the predictions of most climate models. They just don't predict such a long hiatus in warming even as carbon-dioxide emissions from human activity continue to climb.

Note to the president: I do not say that to "defeat or delay" your policies on climate change. The fact is that the U.S. Senate is likely to do that anyway, with or without this information. Early on Election Day, the GOP boycotted a session of the Environment and Public Works Committee in protest of a climate-change bill's costs, and Democrats were split on the legislation as well. Tuesday's election results are likely to give Blue Dog Democrats further pause.

If the Senate does not pass a climate bill that is acceptable to the president, Obama is almost certain to ask the Environmental Protection Agency to issue regulations on carbon-dioxide emissions that he can take to the Copenhagen climate conference next month as evidence of America's efforts. These will then be used to extract some vague concessions on the part of the world's largest emitter of greenhouse gases, China, and the Copenhagen Protocol will be hailed as a major victory over global warming.

Of course, it will be no such thing. If the EPA does issue global-warming regulations, it will have to defend the science that it uses to raise the price of virtually everything. And it is true, Mr. President, that people will use the inconvenient facts of recent climate behavior to defeat or delay the "change" the EPA commands. The administration may respond by "working on" the global-warming people it doesn't like, but it can't "work on" the obvious and growing disconnect between what was forecast and what is happening.

The administration did a great job of increasing the ratings of Fox News. Maybe it can do the same for dissident scientists.

Where's the headline? Where's the television camera? Anyone out there?

It's right there in the September 24 issue of the refereed journal Geophysical Research Letters. The senior author is Marc Tedesco of City College of New York, not exactly off the mainstream media's beaten path. The work was sponsored by NASA.

Every summer (our winter), the edges of Antarctica warm up just enough for some snow to melt. Obviously, a little warming will create quite a bit more melting, which is a factor in dreaded sea-level rise from global warming.

Satellites have been monitoring this activity in both the North and South polar regions since 1980. What Tedesco wrote was this: "A 30-year minimum Antarctic snowmelt record occurred during austral summer 2008-09" (emphasis added).

Here's a graph of his snowmelt data. It was obscured in a very busy chart in the original paper, so I've taken the liberty of stripping it out to stand alone.

Summer Melt in Antarctica Appears to be Declining, not Increasing.

It's obvious that it's not just this year that is of interest. The last three years are clearly those with the lowest aggregate melt on record. You might even see a downward trend since the beginning of the record in 1980.

It's a reasonable surmise that there was no press coverage because there was no press release. NASA is keeping this thing hushed up. (We wouldn't expect environmental journalists to occasionally glance at the scientific literature, such as Geophysical Research Letters, right?).

The Agency is also highly selective about the global warming science it chooses to trumpet. For example, Tedesco has also published on melting in Greenland, and NASA wrote press releases on those papers, which were not nearly as newsworthy as the thirty-year decline in Antarctic melt. Examples:

May 29, 2007: NASA Researcher Finds Days of Snow Melting on the Rise in Greenland. "In 2006, Greenland experienced more days of melting snow and at higher altitudes than average over the past 18 years." Stop the presses! The last we heard each and every year has a fifty-fifty chance of being above (or below) average.

September 20, 2007: NASA Researchers Find Snowmelt in Antarctica Creeping Inland. "…Only satellites can fully capture the extent of changes in snow melting…researchers [including Tedesco] …confirmed that Antarctic snow is melting farther inland…melting at higher altitudes than ever, and increasingly melting on Antarctica's largest ice shelf." How on earth does this square with the obvious decrease in melt just published by the same researchers? Doesn't this press release demand another on the newer work?

Earth to NASA: The 2007 Antarctic paper used twenty years of data, the 2009 paper has the entire record back to 1980. Even looking at the graph through 1998, it's apparent that there is no net increase in melt.

September 25, 2007: NASA Finds Greenland Snow Melting Hit Record High in High Places. This one is unbelievably misleading. "In fact, the amount of snow that has melted this year over Greenland is the equivalent of more than twice the surface size of the U.S.". This is patently impossible — as Greenland's total area is about a quarter of that of the lower 48 states.

There's more. In the most recent paper, Tedesco and his co-authors take pains not to step on a highly publicized study of surface temperature trends published by University of Washington's Eric Steig that was hailed as evidence for human-induced warming. At the time it was published, critics pointed out that there was no trend whatsoever in recent decades and that what warming had occurred took place before the great increase in atmospheric carbon dioxide.

Indeed, Tedesco begins his conclusions by stating that his results "do not contradict" the Steig study. Why? According to Tedesco, because Steig's work begins in the 1950s, long before his 1980 start date. All this did was to confirm that warming pretty much stopped three decades ago. Where's that press release?

NASA's seems to beat the drum only when the news on global warming is bad, and remains mute when it is good. And, for that matter, so is that of the environmental journalism community, apparently incapable of filing an original story about an article from a refereed scientific journal that flies in the face of previous reportage on climate change.

If the G-20 leaders really want to demonstrate commitment to action on climate change, they would do well to be more careful about sticking to their commitments when it comes to open international trade.

Many lofty sentiments were displayed at both events. UN Secretary General Ban Ki-Moon announced that the world is "one step closer" to a climate change deal. But he declined, of course, to point out that this particular journey of a thousand miles looks increasingly precarious and that one step is nowhere near enough progress for those hoping for a final deal in December.

The new Japanese Prime Minister made nice with his colleagues by reaffirming his vow to reduce his country's emissions to 25% below 1990 levels by 2020. China's President Hu Jintao only went so far as to promise his country would reduce emissions by a "notable" margin, but at least sounded receptive to emissions reduction efforts. President Obama gave yet another eloquent speech, which though short on specifics, conveyed that the United States accepted responsibility for past damage, while continuing to insist on efforts from "rapidly-growing developing nations."

On trade, the G-20 will no doubt pledge to work hard to complete the Doha round of multilateral trade negotiations by 2010, and to keep trade open in the meantime. Unfortunately,its record in this area is not great.

The governing body has consistently, if hypocritically in view of its subsequent actions, issued statements emphasizing the importance of avoiding protectionism amid a global financial crisis, only to have its members do the opposite. Too often the temptation among G-20 countries to subsidize and protect their own has proven too great to resist.

The political tension between protection-seeking domestic constituencies and those in favor of more open trade is beginning to appear in the climate change debate. Importantly, the free flow of goods and environmental soundness are not necessarily at odds.

Indeed, because trade leads to wealth, and wealth to an increased desire and ability to protect the environment, the two are complementary. Nonetheless, many G-20 leaders are doing their best to set them up as being inalterably opposed. President Sarkozy earlier this month became the latest politician to call for carbon tariffs to "level the playing field" for French products that will attract a carbon tax and yet compete with untaxed imports.

Similar sentiments are held among certain U.S. politicians too. Senators from manufacturing states crucial to securing passage of a climate bill have repeatedly insisted that their support depends on protection for vulnerable domestic industries. They continue to argue that Chinese imports are threatening U.S. jobs in energy intensive industries, even though more than two-thirds of those types of products come from other similarly rich (and, in some cases, greener) countries.

President Obama spoke out against punitive trade measures inserted into the House bill when it passed in June, but declined to say whether he would veto a final bill if it contained the same elements. He has demonstrated little willingness to resist the siren song of protectionism, judging from his actions on trade since assuming the presidency. He also displayed a lack of appreciation for the foreign policy implications of protectionism in announcing tariffs on Chinese tires just prior to a climate summit where the country's cooperation was considered crucial.

Alienating the Chinese by threatening them with trade barriers would be a big mistake. And considering that the U.S. accounts for less than one percent of the market for Chinese energy-intensive goods as is, tariffs would create even less of an incentive among producers to clean up their production techniques for what would be a shrinking market. What they will do is increase the costs of U.S. producers who use Chinese inputs, and ultimately, of U.S. consumers.

Protectionism in the name of climate change carries little upside and much risk, for the environment and for the global economy. Leaders who care about either or both goals should start fulfilling their own pledges on open trade.

From an outsider's perspective, religious displays of self-inflicted pain can seem pointlessly barbaric. But many anthropologists and evolutionary psychologists believe they have an important function: to facilitate collective action by requiring members to send a costly, hard-to-fake signal of commitment to the group's common creed.

The same impulse, in a rather less impassioned form, seems to animate the Democrats' climate change bill. Coordinating international political action to achieve significant reductions in carbon emissions is a collective action problem of grand, global scale. One way to achieve and maintain such coordinated effort is to detect and punish shirkers. (Governments keep money rolling into their treasuries by threatening tax dodgers with jail.) However, there is no world government with the power to bring wayward nations into line, no world-ranging whip to keep countries pulling in time.

This is the glaring flaw in plans for carbon taxes and cap-and-trade regimes: The world's wealthy nations may now be willing to paddle their boat upstream, but if the developing world won't row along with them, if they insist on a free ride, the boat is going nowhere.

Yet there are other tricks for encouraging cooperation and weeding out "free-riders." Consider the self-flagellating Shiites and face-piercing Thai vegans. These are extreme examples of a cooperation-enabling strategy that game theorists call "costly signaling." Those who display an unflinching devotion to even the most burdensome rules of common life are more likely to pull their weight, to uphold their end of a deal. Talk is cheap, but the willingness to pay a price signals to others the commitment of a real team player.

President Obama would like to walk into the climate-change talks in Copenhagen this December flashing a clear signal that America is willing to pay a price in the fight against carbon and its depredations. Indeed, the best one can hope from the climate legislation languishing in Congress is that, if passed, it will put the world on notice that the United States, the Earth's greatest per-capita carbon font, can be trusted to pull its weight in a global climate deal.

The signal would certainly be costly. According to the Congressional Budget Office, the Waxman-Markey cap-and-trade scheme passed by the House would reduce GDP growth between .03 percent and .09 percent per year for the next 40 years. That may not sound like much, but annual growth rates, like annual interest rates, are compounding, which means that the cost grows considerably over time. At the conservative .03 percent annual penalty, the CBO estimates the U.S. economy in midcentury will be short more than $300 billion a year compared with a future without Waxman-Markey.

What would Americans get in return? Nothing, nada, zip, zilch—unless most of the world plays along. As the CBO put it: "As long as a significant fraction of the world did not adopt similar policies, some of the reductions in the United States would probably be offset by increases in emissions elsewhere." That is to say, if countries like India and China won't agree to (and, more important, stick with) painful cuts that will slow their steady rise from poverty, American sacrifice will do next to nothing to combat the threat of melting ice caps and a more livable Canada.

Costly signals can make sense if they deliver the benefits of cooperation. Won't proof of our faith help skeptical governments in the developing world see that international cooperation is possible after all? It's unlikely.

The Democrats' cap-and-trade bill is stalled in legislative limbo because Americans are far from united about its merits. It would be reasonable for international players to suspect that an American electorate unhappy with the costs of a future carbon cap might have a change of heart. And then there's the bill itself: a patchwork of exemptions, subsidies, and special favors. If political horse-trading produced something so convoluted from the start, it is fair to assume that it will become even more compromised as time goes on, leaving the U.S. unable to actually meet the legislation's aims. Most important, a costly signal clinches trust only among those on the same wavelength. Overheated ultra-orthodox Jews and lacerated Shiite Muslims probably don't much impress each other. Likewise, the signal broadcast by the willingness of wealthy nations to cut their carbon emissions may fail to impress poorer counties with fundamentally different priorities. They are not free-riding if they never asked to be in the boat.

It is hard to see the point of legislation that promises certain costs and improbable benefits. Still, there could be a point. Many Americans would find profound meaning in passing legislation like Waxman-Markey and gladly bear its costs—even if it does little to secure international cooperation, and even if it does nothing to slow global warming. The law would nevertheless speak to what Americans value, what we aspire to, who we are, what we're about. It would say that we're not so bad, that we repent our industrial sins, that over here we know full well that green is the new black.

Alas, this is not a statement of faith most Americans are prepared to make, or a cost they are prepared to pay. They should not be asked to don a green hair shirt just to show the world that some of us care.

Imagine if there were no reliable records of global surface temperature. Raucous policy debates such as cap-and-trade would have no scientific basis, Al Gore would at this point be little more than a historical footnote, and President Obama would not be spending this U.N. session talking up a (likely unattainable) international climate deal in Copenhagen in December.

Steel yourself for the new reality, because the data needed to verify the gloom-and-doom warming forecasts have disappeared.

Or so it seems. Apparently, they were either lost or purged from some discarded computer. Only a very few people know what really happened, and they aren't talking much. And what little they are saying makes no sense.

In the early 1980s, with funding from the U.S. Department of Energy, scientists at the United Kingdom's University of East Anglia established the Climate Research Unit (CRU) to produce the world's first comprehensive history of surface temperature. It's known in the trade as the "Jones and Wigley" record for its authors, Phil Jones and Tom Wigley, and it served as the primary reference standard for the U.N. Intergovernmental Panel on Climate Change (IPCC) until 2007. It was this record that prompted the IPCC to claim a "discernible human influence on global climate."

Putting together such a record isn't at all easy. Weather stations weren't really designed to monitor global climate. Long-standing ones were usually established at points of commerce, which tend to grow into cities that induce spurious warming trends in their records. Trees grow up around thermometers and lower the afternoon temperature. Further, as documented by the University of Colorado's Roger Pielke Sr., many of the stations themselves are placed in locations, such as in parking lots or near heat vents, where artificially high temperatures are bound to be recorded.

So the weather data that go into the historical climate records that are required to verify models of global warming aren't the original records at all. Jones and Wigley, however, weren't specific about what was done to which station in order to produce their record, which, according to the IPCC, showed a warming of 0.6° +/- 0.2°C in the 20th century.

Now begins the fun. Warwick Hughes, an Australian scientist, wondered where that "+/-" came from, so he politely wrote Phil Jones in early 2005, asking for the original data. Jones's response to a fellow scientist attempting to replicate his work was, "We have 25 years or so invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it?"

Reread that statement, for it is breathtaking in its anti-scientific thrust. In fact, the entire purpose of replication is to "try and find something wrong." The ultimate objective of science is to do things so well that, indeed, nothing is wrong.

Then the story changed. In June 2009, Georgia Tech's Peter Webster told Canadian researcher Stephen McIntyre that he had requested raw data, and Jones freely gave it to him. So McIntyre promptly filed a Freedom of Information Act request for the same data. Despite having been invited by the National Academy of Sciences to present his analyses of millennial temperatures, McIntyre was told that he couldn't have the data because he wasn't an "academic." So his colleague Ross McKitrick, an economist at the University of Guelph, asked for the data. He was turned down, too.

Faced with a growing number of such requests, Jones refused them all, saying that there were "confidentiality" agreements regarding the data between CRU and nations that supplied the data. McIntyre's blog readers then requested those agreements, country by country, but only a handful turned out to exist, mainly from Third World countries and written in very vague language.

It's worth noting that McKitrick and I had published papers demonstrating that the quality of land-based records is so poor that the warming trend estimated since 1979 (the first year for which we could compare those records to independent data from satellites) may have been overestimated by 50 percent. Webster, who received the CRU data, published studies linking changes in hurricane patterns to warming (while others have found otherwise).

Enter the dog that ate global warming.

Roger Pielke Jr., an esteemed professor of environmental studies at the University of Colorado, then requested the raw data from Jones. Jones responded:

Since the 1980s, we have merged the data we have received into existing series or begun new ones, so it is impossible to say if all stations within a particular country or if all of an individual record should be freely available. Data storage availability in the 1980s meant that we were not able to keep the multiple sources for some sites, only the station series after adjustment for homogeneity issues. We, therefore, do not hold the original raw data but only the value-added (i.e., quality controlled and homogenized) data.

The statement about "data storage" is balderdash. They got the records from somewhere. The files went onto a computer. All of the original data could easily fit on the 9-track tape drives common in the mid-1980s. I had all of the world's surface barometric pressure data on one such tape in 1979.

If we are to believe Jones's note to the younger Pielke, CRU adjusted the original data and then lost or destroyed them over twenty years ago. The letter to Warwick Hughes may have been an outright lie. After all, Peter Webster received some of the data this year. So the question remains: What was destroyed or lost, when was it destroyed or lost, and why?

All of this is much more than an academic spat. It now appears likely that the U.S. Senate will drop cap-and-trade climate legislation from its docket this fall — whereupon the Obama Environmental Protection Agency is going to step in and issue regulations on carbon-dioxide emissions. Unlike a law, which can't be challenged on a scientific basis, a regulation can. If there are no data, there's no science. U.S. taxpayers deserve to know the answer to the question posed above.

But even though it's now clear the bill is not getting out of Congress, look for the Obama Administration to saddle our economy with this huge new energy tax through other means.

First, a brief flashback: The blowback against Obamunism began over global warming, not health care. By a squeaky 219-212 vote, the House rushed the 1,300-page cap-and-trade opus out the door so the members could get back to the hustings for the Fourth of July. When many freshman Democrats got home, those who voted for it experienced the first angry town halls of their careers. In our minds, it is easy to remember that the rancorous public meetings that continued in the August recess were always about health care, but they weren't.

So, given that health care is now effectively bottled up in both chambers of Congress, why isn't Obama pushing cap-and-trade in the Senate? Simple: the votes aren't there for it. Blanche Lincoln, the new head of the Agriculture Committee, calls cap-and-trade a "complete non starter" and said that it is not her "preference to move on cap and trade this year." Majority Leader Harry Reid recently signaled his agreement by stating that cap-and-trade "may" not be considered until next year.

For cap-and-trade, "next year" translates as "never." Senators know what touched off the town halls, and they know what fate awaits many of their Democratic colleagues come November 2010. Passing an unpopular health care "public option" along with cap-and-trade will easily realign the Senate into its old filibustering self. That kills cap-and-trade in the next Congress.

But do not despair, fans of economy-killing regulation.

Thanks to the Supreme Court's landmark decision in Massachusetts v. Environmental Protection Agency (2007), the EPA has authority to issue its own regulations on carbon dioxide. So while asking legislators to swallow hard on the bitter gristle of cap-and-trade, the president has really had the power to enact its core components on his own all along. Small wonder lawmakers of his own party are more than willing to toss the issue back onto his plate.

Now that cap-and-trade has so spectacularly failed in the legislature, it is a sure bet that Obama will direct (or has directed) EPA Administrator Lisa Jackson to issue her own cap-and-trade protocols. Look for something concrete out of EPA before the U.N.'s climate change confab in Copenhagen in early December. (That "something" may even include a new fuel economy standard of 35.5 miles-per-gallon—though it would be lower, of course, for the inefficient cars produced by government-owned General Motors.)

The timing of the Copenhagen conference is really what has been driving Obama's support for cap-and-trade all along. It would be an embarrassment for a left-hewing "green" president to show up empty-handed at such an event—and it will greatly diminish Obama's ability to wag his finger at other industrialized countries. For sure, the world's largest emitter of CO2—China—isn't going to agree to any mandatory emissions reductions unless the U.S. has something very serious in hand. And if China does nothing, there's simply not going to be a major slowdown in the growth of atmospheric greenhouse gases.

Not that it really matters. The rather large elephants crowding cap-and-trade out of the Senate is the earth's reluctance to warm in the last decade along with new projections saying that we could go another ten years without much warming.

The current hiatus in warming portends a reduction in potential heating for the entire century. Most computer models produce significant warming as a result of an increase in atmospheric water vapor (a "greenhouse" gas), which comes from an ocean initially warmed by carbon dioxide. When the ocean doesn't warm much, this "feedback" effect is delayed. Or so goes the myth.

The lack of warming is an embarrassment to any elected official who has been hiding behind "the science is settled" fig leaf in order to promote cap-and-trade. While every scientist will tell you that indeed the surface temperature of the planet is warmer than it was a century ago (that's the "settled" part of global warming science), very few scientists anticipated as long a period without warming as we are in. In other words, the real science of future warming is completely unsettled.

The bottom line is that Senate Democrats are perfectly happy to kick cap-and-trade under the bus. They're going to have a hard enough time recovering from the upcoming health care wreck. But the economy, meanwhile, will have an equally hard time recovering from what President Obama is going to do instead.

First, the key targets of the proposed import barriers, India and China, are relatively minor sources of imports of energy-intensive goods. Most carbon-intensive imports to the United States come from other developed countries that have stricter emissions controls than the United States and will therefore likely escape import penalties. Second, and more fundamentally, the trade provisions may be counterproductive. Global trade rules allow import barriers to protect the environment under certain conditions, some of which the main climate change bill appears to contradict. A trade dispute and possible retaliation is not in anyone's interest, especially in a global downturn. Even if the United States was able to avoid formal dispute settlement proceedings, copycat regulations in other countries may be designed in a manner unfavorable to U.S. interests.

To the extent that global warming is a real problem warranting action, it needs to be addressed globally rather than through unilateral efforts. Antagonizing trade partners through probably illegal trade measures will undermine efforts to secure global cooperation on climate change. A freer, more prosperous economy is a more auspicious path to ensuring a more rapid spread of environmental technology and the global consensus needed to combat climate change.

First, before Congress approved the Interstate Highway System, it had a good idea how much it would cost. In contrast, Congress approved $8 billion for high-speed rail without knowing the total cost, which is likely to be at least $90 billion.

Second, highway users paid for interstate highways, whereas high-speed rail will be almost entirely subsidized by general taxpayers who will rarely use it.

Third, interstate highways connect all 48 contiguous states and major metropolitan areas. The FRA's high-speed rail plan consists of six unconnected networks that reach only 33 states and less than two-thirds of the nation's 100 largest urban areas.

Fourth, the average American traveled 4,000 miles on interstates in 2007. High-speed rail proponents optimistically estimate that the average American would ride the FRA's high-speed rail system less than 60 miles per year.

Finally, interstate highways improved social welfare by increasing highway safety. In contrast, far from saving energy and reducing pollution, high-speed rail would actually increase energy consumption and greenhouse gas emissions.

For all these reasons, the United States government should not fund high-speed rail. The $8 billion in high-speed rail stimulus funds should be invested in safety improvements, not in new trains and new routes that will add to future taxpayer obligations.

Ethanol is sustainable by definition. The CO2 sequestered by growing corn is exactly offset by the CO2 emissions that follow from burning the fuel in a car. The same observation applies to, say, drinking bourbon made from corn.

Are CO2 emissions due to operating an automobile any worse than emissions due to digestion? The only difference is that ethanol can replace gasoline—bourbon cannot. Hence, a logical sustainability standard would be tougher on bourbon and all other products made from corn —products that can negatively impact health, like beef, bacon, butter, Buffalo wings etc. – and a lot easier on ethanol which is more greenhouse-friendly than other corn-based products and saves lives by powering ambulances to hospitals.

The EPA's sustainability standard is based on "life-cycle accounting" (LCA), a "well to wheel" measure of greenhouse gas emissions in the production of gasoline and a "field to fuel tank" measure for ethanol production. While attractive in theory, LCA fails to recognize that if incentives are given for ethanol producers to use relatively "clean" inputs (e.g., natural gas and land previously used for soybean cultivation), the "dirtier" inputs (e.g., coal and land previously dedicated to rainforests) that might otherwise have been used will simply be used by other producers to make products not covered by the sustainability standard.

In short, sustainability standards reshuffle who is using what inputs with no net reduction in national emissions. LCA measures are therefore misleading and may not measure the actual greenhouse gas emissions saved by ethanol production.

Rather than try to get LCA right, the entire exercise should be scuttled altogether. The difficulties associated with a sensible calculation are simply too great.

LCA assumes, for instance, that ethanol will replace gasoline, but it may actually replace coal or other energy sources, especially since oil supply is generally thought of as "finite" while coal is considered "unlimited in supply." This is not simply a matter of theory. In developing countries like Brazil, electricity is generated by harnessing leftover sugar cane, thereby potentially replacing coal-based electricity. It is also possible for biofuels to replace wood currently used for home cooking and heating, both of which impose huge health and environmental costs in developing countries. The upshot is that LCA will almost certainly undercount the greenhouse gas emissions that are "saved" by ethanol as well as other problematic air emissions.

Nor is LCA any easier when we apply it to the oil sector. The direct and indirect effects of oil pollution in the Ecuadorian jungle, for instance, would have to be measured, as would the environmental impacts of site specific drilling everywhere else on the globe.

To make matters worse, the argument over sustainability standards diverts attention from the contradictory and wasteful stew of federal ethanol policies – import tariffs, tax credits, mandates and production subsidies – which exist whether ethanol is sustainable or not. Our research shows that these policies generate tens of billions of dollars per annum of economic inefficiencies. Ensuring that ethanol is "sustainable" does not make those costs disappear. To just take one example, combining a tax credit for ethanol with a binding mandate requiring a minimum level of consumption will subsidize gasoline consumption instead of ethanol consumption, resulting in an increase in CO2 emissions, traffic congestion, and dependence on foreign oil.

Sustainability standards for ethanol make no sense. If we want to tackle greenhouse gas emissions, the most efficient means of doing so it to impose a carbon tax (explicitly through the tax code or implicitly with a cap & trade emissions program) on oil and natural gas at the refinery, coal at the plant using the coal, and land at time of conversion into the production of biofuels, bourbon, shopping malls, etc. That covers all of the relevant sectors of the economy in a fair and efficient manner. "Fair" and "efficient," however, are not words one would use to describe sustainability standards for ethanol.

The politics of global warming are becoming increasingly disconnected from the people. Day after day, hour after hour, telescreens shout, "Go Green! Go Green!" Fewer and fewer people care.

On April 19, Rasmussen Reports released a new global warming poll: 48 percent of respondents believe that observed climate changes are being "caused by planetary trends," while 34 percent believe they are a result of human influence on the atmosphere. When Obama was sworn in, the relative numbers were 44 percent and 41 percent. Just three months ago, opinion was pretty much evenly split, and now there's a whopping 14 percent plurality in favor of "natural causes."

This is a change from bad to worse in the eyes of environmentalists. In January, Gallup found that, out of 20 prominent issues, Americans ranked global warming dead last in terms of importance. If the newer Rasmussen results are any guide, support has waned even further since then.

If the political class would have done its homework, it would have seen this coming. The incessant hype has generated a massive political backlash. It was first documented over a year ago in the refereed journal Risk Analysis, by Paul Kellstedt and two colleagues, political scientists at Texas A&M University.

The standard thinking is called the "knowledge deficit" model. That's academese for the notion that the poor blokes aren't concerned about global warming because they're just stupid and haven't heard enough about it. Obviously no one watches television any more (CNBC's peacock is green this week), walks outside in major urban downtowns (plastered with billboards and posters — from energy companies — urging their customers to use less of their products), or goes to the movies (The Day After Tomorrow, An Inconvenient Truth, Ice Age: The Meltdown, etc).

Actually, people still do go to the movies, and watch TV, and are assaulted every urban minute with global-warming propaganda. And, according to Kellstedt, the more people know about global warming, the less they care:

Contrary to the assumptions underlying the knowledge-deficit model, as well as the marketing of movies like Ice Age or An Inconvenient Truth, the effects of information on both concern for global warming and responsibility for it are exactly the opposite of what were expected.

Jon Gertner touched on this in last Sunday's New York Times Magazine. He noted that debate as to why climate change isn't higher up on the priority totem-pole usually is blamed on "the doubt-sowing remarks of climate-change skeptics," or "the poor communication skills of good scientists."

This prism has bent the light on global warming exactly wrong. In fact, it is the communication skills of scientists that are responsible for people's opinions. Kellstedt found that people "with high confidence in scientists . . . show less concern for global warming," as did the "more informed respondents." Americans' lack of alarm has less to do with "skeptics" than it does with people's perception of mainstream science.

Interestingly, this is parallel to other issues at the science-political nexus. Despite years of campaigning against genetically modified (GM) food on the part of many environmentalists, the more people learn, the less concerned they are about that, too.

Maybe this has to do with the fact that Americans have been consuming, in one form or another, GM food for decades, and we obviously aren't dead yet. Sober scientists note that GM foods are nutritionally indistinguishable from their progenitors — so when someone else loudly and angrily foretells disaster upon disaster that will befall us from the use of GM products, people say "so what?" And when they see some movie about the horrors of global warming — if they know that scientists observe that the planet's surface has been warming episodically and modestly for a century — they likewise say, "So what? It's a movie."

Washington would be well-advised to pay attention to what folks are telling pollsters out beyond the Beltway.

But it's Earth Day, so I expect the response of the political class here will likewise be, "So what?"

Not surprisingly, the United Nations has just jumped on President Obama's hybrid bandwagon, demanding yet another trillion dollars (coming mostly from you-know-who) to fund "A Global Green New Deal for Sustainable Development." Translation: The U.S. will provide funds to poorer nations so that they, too, can tell their private companies what to make, whom to employ, and how much to pay them. The U.N. wants your money pronto, by the end of next year.

The U.N.'s "deal" really amounts to drastic interference in the development of other nations that are neither recipients of nor contributors to the cool Trillion. India's Tata Motors has just unveiled a $2,000 mini-car, which could be a hit in a lot of poor countries. China's Cherry is poised for a global pounce as soon as liquidity reappears. But the U.N. proposes to spend our money fighting "automobiles, which are environmentally harmful," promoting instead a "shift to clean public transport" which they then call "clean fuel buses."

Huh? So the UN is hoping to close developing markets in poor countries to developing producers in countries a tier or two up the economic ladder, and then substitute a nonexistent technology?

Our researchers are still busy at work trying to figure out what a "clean fuel bus" is. It can't be one run on ethanol, because that takes more energy to produce than we currently get out of it. If it's run on electricity produced by solar panels, the physics become daunting. An array required to run just one bus for 100 miles per day would stretch over ten miles. And where would the energy come from at night?

Like Obama's initiatives, the U.N.'s purpose is to provide "green jobs." Nothing new here. Germany put in a similar program a few years ago, sending out an army of people otherwise employed or not employed to install solar panels. German taxpayers subsidized each of these 35,000 jobs at $170,000 apiece. Now the UN wants to do the same with your money — all over the world.

Worse still, the "Green New Deal" wants energy subsidies from you — called global "feed-in tariffs" — to boost inefficient energy sources. This reverse tariff would "overcome" the "difficulty" of noncompetitive energy, providing guaranteed purchase prices to producers in developing countries for a period of 20 years. The electricity would then be sold to final consumers at a lower price.

What's the difference between a "feed-in" tariff and a real one? There isn't one. It basically says that anyone who has cheaper electricity for sale across national borders need not apply. As is the case with Obama's cap-and-trade energy taxes here in the States, the U.N. says their tax on us is "desirable on climate-related grounds."

Nothing is new here. The U.N. is hoping for more green stimulus from an already overstimulating and intrusive president, and returning more of the same: higher taxes, and technologies that won't work and that will cost a fortune.

Most previous science had indicated that, despite a warming of global temperatures, readings from Antarctica were either staying the same or even going down.

The problem with Antarctic temperature measurement is that all but three longstanding weather stations are on or very near the coast. Antarctica is a big place, about one-and-a-half times the size of the US. Imagine trying to infer our national temperature only with stations along the Atlantic and Pacific coasts, plus three others in the interior.

Eric Steig, from University of Washington, filled in the huge blanks by correlating satellite-measured temperatures with the largely coastal Antarctic network and then creating inland temperatures based upon the relationship between the satellite and the sparse observations. The result was a slight warming trend, but mainly at the beginning of the record in the 1950s and 1960s. One would expect greenhouse effect warming from carbon dioxide to be more pronounced in recent years, which it is not.

There's actually very little that is new here. Antarctic temperatures do show a warming trend if you begin your study between 1957, when the International Geophysical Year deployed the first network of thermometers there, and the mid-1960s. Studies that start after then find either cooling or no change.

Steig and his colleagues didn't graph the data for the continent as a whole. Instead they broke it into two pieces: the east and west Antarctic ice sheet regions. A naïve reader would give equal weight to both. In fact, in the east, which is much larger, there is clearly no significant warming in the last several decades. When the results are combined, the same old result reappears, namely that the "warming" is driven by years very early in the record, and that the net change since the early 1970s is insignificant.

The reaction to this study by Steig and his co-authors is more enlightening than its results. When Antarctica was cooling, some climate scientists said that was consistent with computer models for global warming. When a new study, such as Steig's, says it's warming, well that's just fine with the models, too. That's right: people glibly relate both warming and cooling of the frigid continent to human-induced climate change.

Perhaps the most prominent place to see how climatologists mix their science with their opinions is a blog called RealClimate.org, primarily run by Gavin Schmidt, one of the computer jockeys for Nasa's James Hansen, the world's loudest climate alarmist.

When studies were published showing a net cooling in recent decades, RealClimate had no problem. A 12 February 2008 post noted: "We often hear people remarking that parts of Antarctica are getting colder, and indeed the ice pack in the southern ocean around Antarctica has actually been getting bigger. Doesn't this contradict the calculations that greenhouse gases are warming the globe? Not at all, because a cold Antarctica is just what calculations predict ... and have predicted for the past quarter century."

A co-author of Steig's paper (and frequent blogger on RealClimate), Penn State's Michael Mann, turned a 180 on Antarctic cooling. He told Associated Press: "Now we can say: No, it's not true. ... [Antarctica] is not bucking the trend."

So, Antarctic cooling and warming are both now consistent with computer models of dreaded global warming caused by humans.

In reality, the warming is largely at the beginning of the record — before there should have been much human-induced climate change. New claims that both warming and cooling of the same place are consistent with forecasts isn't going to help the credibility of climate science, and, or reduce the fatigue of Americans regarding global warming.

Have climate alarmists beaten global warming to death? The Pew Research Centre recently asked over 1,500 people to rank 20 issues in order of priority. Global warming came in dead last.

We can never run the experiment to see if indeed it is the constant hyping of this issue that has sent it to the bottom of the priority ladder. But, as long as scientists blog on that both warming and cooling of the coldest place on earth is consistent with their computer models, why should anyone believe them?

Bedritsky states that "human activities are altering the climate at an increasingly alarming rate." However, according to data from the United Nations Intergovernmental Panel on Climate Change (IPCC), the rate of planetary warming that was established in the mid-1970s has been remarkably constant, varying only slightly from 0.17°C per decade.

The 21 computer models used by the IPCC share a common ensemble characteristic: for the midrange emissions scenario they, too, predict a constant rate of warming, not an "increasing" rate. The models simply produce different rates. As a meteorologist, Bedritsky knows that the way to adjudicate between differing forecast models is to literally "look out the window" to see which is performing the best. In the case of climate models, looking at the warming trend that has been established accomplishes the same, and yields a 21st century warming of 1.7°C, which is within, but near the low end, of the entire range of projections made by the IPCC.

Even this may be an overestimation. It is very clear, from both the IPCC data and from satellite measurements, that there has been no net warming since 1998 (which was a record year because of a very strong El Niño warming in the tropical Pacific). Further, as noted by Keenlyside et al. in Nature earlier this year, Atlantic and Pacific temperature patterns indicate that little warming can be expected for several more years. Many of the IPCC's climate models are indeed capable of reproducing El Niño-like temperature excursions, but none—not one—of the models illustrated in the IPCC's 2007 report projects a period of 15 years with no net warming.

Bedritsky's statement about a "marked decline" of global ice cover is also contextually incomplete. Sea-ice in the Northern Hemisphere, mainly in the Arctic Ocean, has declined significantly since systematic measurements began in 1979, but 1979 was at the end of the coldest period in the Arctic since the mid-1920s. While the recent decline is clearly related to warming temperatures, paleoclimatic evidence from northern Eurasia indicates that late summer sea-ice in the Arctic was likely to have been very spotty or non-existent for millennia after the end of the last ice age. Obviously the polar bear and the Inuit survived. Ice extent measured by satellite in the Southern Hemisphere has increased and was at record high levels, adjusted for season, earlier this year.

I think Bedritsky's article would have been more complete, if less alarming, if he had noted these observations about climate history, climate models, and ice.

Their omission reminds me of President Eisenhower's fears that a technological elite could acquire inordinate power. In his farewell address,famous for its introduction of the notion of a "military-industrial" complex, Eisenhower went on to say something equally prescient and disturbing, "Holding scientific research and discovery in respect, as we should, we must always be alert to the equal and opposite danger that public policy could itself become a captive of a scientific-technological elite."

This is precisely the danger that accrues when authoritative scientists do not communicate complete information to the public.

Because the 103 estimates come from only 28 studies and are therefore not really 103 independent estimates, Tol produces weighted estimates of the mean, mode, and median that proportionately reduce the weight given to multiple estimates from a given study. If a study produces one estimate of the mean, it gets a weight of one. If a study has seven estimates of the mean, they each get a weight of one seventh. Calculated this way, the median estimate for the cost of emitting a ton of carbon in those studies is $14. The mean estimate is $93 per ton. And the modal estimate is $2 per ton (all numbers rounded to the nearest dollar).

Tol then calculates estimates that vary the weight of each study along several subjective dimensions. Was the study peer reviewed? Was the study based on an independent impact assessment of climate change? Did the study rely on dynamic climate change scenarios? Was the study based on explicit economic scenarios? Did the study estimate marginal damage costs rather than average costs? Each "yes" to the above questions earned the study one point (meaning a 5-point study was given proportionally more weight than a 1-point study). He then gave each study an additional 0.1 point for each year in which the study was published since 1990, thus giving more weight to newer rather than older studies.

The median cost estimate for carbon emissions in Tol's quality-weighted data set is $16 per ton ($2 more than without quality weights). The mean estimate is $129 per ton ($36 more than without quality weights). The modal estimate remains at $2 per ton.

When Tol eliminated the studies that weren't peer reviewed, the median quality-weighted cost estimate fell to $14 per ton, the mean to $50 per ton, and the mode increased to $5 per ton.

The large difference between the mean and median estimates as well as the low modal estimate highlight the large variation in the carbon-cost estimates as well as a large "right-tail" in the distribution. That variation is explained for the most part by (1) the discount rate applied to future costs and benefits, and (2) the manner in which monetarized costs were aggregated across countries. That is, it's not so much that study x found high costs because the authors of study x concluded that sea level rise would be more economically devastating than, say, study z. It's that study x used a 1% discount rate for those future sea-level-rise costs while study z used, say, a 3% discount rate. And study x weighted damages in poorer countries more than in wealthier countries.

Tol reports that, if he removes those studies engaged in "equity weighting" from the dataset, median carbon emissions costs are $10 per ton. Mean costs are $90 per ton. Modal costs are $2 per ton. And when he removes studies from the dataset using a 1% or lower discount rate, he found that median carbon emissions costs were $7 per ton, mean $16 per ton, and mode $2 per ton.

"If we take all studies without discriminating between them, the best guess for the marginal damage costs of carbon dioxide emissions is $5 per ton," writes Tol, but "there are good reasons to discriminate between studies ... it appears that studies with better methods yield lower estimates with smaller uncertainties than do studies with worse methods. If one excludes the studies in the gray literature, the combined marginal damage cost estimate falls further, and so does its uncertainty. It seems as if the most pessimistic estimates of climate change impacts do not withstand a quality test."

Given that, what's the "best" guess available from the literature published through 2004? When asked that question by Danish statistician Bjorn Lomborg, the answer he gave was $2 a ton (an answer reported in Lomborg's book Cool It). $2 a ton is the most frequent value in the data, or mode. Because environmentalists worship at the alter of "consensus" when discussing the science of climate change, a similar emphasis on a show of hands in the economics professions suggests a modal — not a mean or median — calculation. Hence, we have been comfortable using Tol's $2 per ton figure when discussing what the economics literature has to say about the cost of carbon emissions.

In a recent on-line debate with Joe Romm, however, Tol's 2005 review of the literature was dismissed by Joe because it was old and has been superseded by more recent work; in particular, the IPCC's 4th assessment on climate change (published last year) and the Stern Review on the economics of climate change (released in 2006). More importantly, Tol updated his literature review last August — of which we were unaware — and, according to one blogger, "Taylor's quoting of old numbers that Tol has himself moved away from looks like cherry-picking and in any case will not convince anyone who has moved on from 2004."

So what does Tol report now?

Well, it's certainly true that the literature has expanded a bit. Nineteen studies have been published since Tol's 2005 paper and, as a consequence, there are now 108 new marginal cost estimates to consider. Yet this explosion of published work is somewhat misleading given that all of those studies are based upon only 12 underlying papers estimating the total costs of climate change, and only two of those studies were published since Tol's 2005 survey of the literature. The (raw unweighted) median estimate for the cost of emitting a ton of carbon from the 211 estimates in those studies is $29. The mean is $105 per ton. And the mode is $6 per ton (all numbers rounded to the nearest dollar). Those numbers are remarkably similar to the raw 2005 estimates of $26, $97, and $6 respectively.

If one thinks of the 211 estimates as a sample of data drawn from an unobserved population, what type of population is it? Is it normally distributed or something else? In his 2005 paper, Tol assumed normality. In his 2008 paper, Tol now considers three possible distributions: the normal distribution; the normal distribution with normalized standard deviations (standard deviation divided by the mean, which is also called coefficient of variation), and Fisher-Tippett (which, unlike the normal distribution, is skewed right). Given the right skew to the 2005 data (mean>median>mode), this would seem to be an obvious addition.

Table 1 summarizes the median, mean, mode, and standard deviation findings for each of these three probability density functions after Tol's 2005 quality-weights are applied to the 2008 data set. Standard deviations are also offered. Findings are then further subdivided based on discount rate, peer review, and publication date.

Some observations about Table 1.

First, the widely-held belief that recent studies argue that the costs of climate change will be higher than previously thought — an argument presented in the most recent IPCC report and by Joe Romm in our recent on-line exchange — is incorrect with one exception. That is the mode, median, and mean estimates of costs are highest in the oldest studies and lowest in the most recent studies. The one exception is the median estimate in the normal distribution using the coefficient of variation, which increases with time from $14 a ton to $16 and $17, but that change is very small.

Second, some of Tol's 2008 estimates are larger than his 2005 cost estimates and some are not. Recall that Tol's quality-weighted 2005 median, mean, and mode findings were $16, $129, and $2 per ton respectively. His 2008 cost estimate using the normal distribution (coefficient of variation) is lower: $15, $102, and $0 per ton respectively. The 2008 estimates using normal distribution (standard deviation) and Fisher-Tippett have higher medians, lower means, and higher modes: $47, $88, and $33 and $74, $127 and $35, respectively.

Third, just as in 2005, the "better" (peer reviewed) studies in the literature produce lower cost estimates relative to non peer reviewed studies with the exception of the mode in the normal (coefficient of variation), which rises from $0 to $3.

Fourth, just as in 2005, large cost estimates flow from low discount rates (pure rate of time preference) and low cost estimates flow from higher rates of pure time preference.

The contention that Tol has "moved away" from his 2005 numbers is literally true. The most important difference between Tol 2008 and Tol 2005 is that Tol 2008 considers three probability density functions rather than the one employed in Tol 2005. Two of those three probability density functions report more varied (higher and lower) cost estimates than those reported in Tol 2005.

Tol argues in his 2008 paper that the social cost of carbon emissions is positive, that there is so much uncertainty regarding costs that "a considerable risk premium is warranted," and that, consequently, "greenhouse gas emission reduction today is justified." Those declarations did not appear in his 2005 paper, but they are not inconsistent with the findings of that paper. There is a difference, of course, between a discussion about the social cost of carbon emissions and a discussion about appropriate carbon taxes. The former informs but does not dictate the latter. Tol 2005 discussed only the former. Tol 2008 discusses primarily the former but briefly touches on the latter as well.

Regardless, one can embrace the findings of Tol's meta-analysis without embracing Tol's interpretation of how best to translate that meta-analysis into public policy. The literature suggests that the social cost of carbon emissions is likely positive, but that alone does not justify a carbon tax. If the social cost is only a few dollars a ton, the political and economic transaction costs associated with imposing a carbon tax would likely exceed the benefits. Moreover, there may be less expensive ways of reducing harm than imposing carbon taxes or emission trading regimes. Uncertainties there may be, but if we discount the future by 3 percent annually (a discount rate that seems appropriate given opportunity costs), the high-cost scenarios that so heavily weight these analyses vanish into thin air. That's because most of the damages associated with climate change will occur many decades in the future and even small differences regarding the economic impact of those damages produces highly variant estimates. Discount the future, however, and the (economic) importance of those disagreements all but disappears.

So what does Tol 2008 tell us about the social cost of carbon emissions (assuming that the underlying science from the IPCC is correct)? Given our skepticism about the underlying logic of discount rates of 1% or less, any number between $3 per ton and $24 per ton seems defensible. The lower end of that distribution would seem to be more reasonable, however, keeping in mind that the better and more recent studies produce lower cost estimates than do others.

Al Gore himself descends on Wednesday to personally bless the conclave's work product — which, based on past history, we can be assured will range somewhere between flawed, fraudulent, and downright farcical.

Kyoto was supposed to reduce global emissions of carbon dioxide below 1990 levels during the period 2008–2012. But, since it was signed, the atmospheric concentration of this putative pollutant continued to rise, pretty much at the same rate it did before Kyoto. Incidentally, even if the world had lived up to the letter of the Kyoto law, the effect on global temperature would have been too small to measure.

The purpose of the Poznan meeting is to work out some type of framework that goes "beyond Kyoto." After completely failing in its first attempt to limit carbon dioxide emissions internationally, the U.N. will propose reductions even greater than those Kyoto required. Kyoto failed because it was too expensive. Anything "beyond" it will cost that much more, and is even less likely to succeed.

Besides, the world cannot afford any expensive climate policies now. Economic conditions are so bad that carbon-dioxide emissions — the byproduct of our commerce (not to mention our respiration) — are likely falling because of the financial chill, not the climatic one. Indeed, a permanent economic ice age would likely result from any mandated large cuts in emissions.

And, before proposing an even harsher treaty, the U.N. ought to pay attention to its own climate science. It regularly publishes temperature histories from its Intergovernmental Panel on Climate Change (IPCC), which was formed in the late 1980s with the express charge of finding a scientific basis for a global climate treaty.

Since Kyoto in December 1996, a very funny thing has happened to global temperatures: IPCC data clearly show that warming has stopped, even though its computer models said such a thing could not happen.

According to the IPCC, the world reached its high-temperature mark in 1998, thanks to a big "El Niño," which is a temporary warming of the tropical Pacific Ocean that occurs once or twice a decade. El Niño years are usually followed by one or two relatively cold years, as occurred in 1999 and 2000. No one knows what really causes these cycles but they have been going on sporadically for millennia.

Wait a minute. Starting an argument about global warming in 1998 is a bit unfair. After all, that's starting off with a very hot temperature, followed by two relatively cool years.

Fine. Take those years out of the record and there's still no statistically significant warming between 1997 and 2007. When a scientist tells you that some trend is not "significant," he or she is saying that it cannot mathematically be distinguished from no trend whatsoever.

More importantly, there's not going to be any significant trend for some time. Assume, magically, that temperatures begin to warm in 2009 at the rate they were warming before the mid 1990s, and that they continue to warm at that rate. The world has to warm in such a fashion through 2020 before there's a significant trend reestablished in the data. That's a full quarter century for any discernable trend of global warming to emerge.

That, however, is not what the U.N.'s own models show. The IPCC's latest (2007) compendium on climate used 21 different climate models to forecast the future, and subjected each to different "storylines" (in the U.N.'s parlance) for global emissions of carbon dioxide. They are there for the world to see, on page 763 of the volume on climate science. Not one of them predicts a quarter century without warming — even under a scenario in which emissions increase more slowly than they already are.

The U.N.'s own climate models have failed barely a year after they were made public. They have demonstrated a remarkable inability to even "predict" the present. Will 10,000 people in Poznan somehow ignore this?

They shouldn't. Instead they should be thankful. The lack of recent and future warming almost certainly means that the ultimate warming of this century is going to be quite modest. And they should keep in mind that expensive policies to fight a modest climate change will only worsen the cold snap currently affecting the global economy.