|The Week That Was
Aug. 13, 2005
Another exciting week. Yet another failed attempt to find the 'smoking gun' for anthropogenic global warming (AGW). Jim Hansen's "deep ocean" approach got shot down - we think. (At least, Hansen has not responded to our critique, which was e-mailed to him in advance.)
What to make of three papers in Science Express (published on-line on 11 August, to be printed in Science in about a month): (1) A re-analysis of satellite temperature data (by Mears and Wentz --MW), (2) of balloon radiosonde temperatures (by Sherwood et al), and (3) an analysis comparing surface and atmospheric temperature trends ( by Santer et al) . Some claim to see here the long-sought validation of climate models. We don't agree.
MW found an error in the data analysis published by Christy and Spencer (CS), which used to show a slight warming trend of 0.09 C per decade. After correction (see Items #1 and 2 for the gory details), the trend increases to 0.12 C - not a big deal. But MW's own analysis gives 0.19 C - and no one has yet explained this difference. Note however, that the CS result agrees with the corrected balloon trends.
Now the fun begins. Greenhouse theory says (and the models calculate) that the atmospheric trend should be 30% greeter than the surface trend - and it isn't. Furthermore, the models predict that polar tends should greatly exceed the tropical values - and they clearly don't do that . In fact, the Antarctic has been cooling. So there.
And don't forget: Models still cannot model clouds. The latest modeling exercise (Stainforth et al. Nature 27 Jan., 2005) obtained a warming (for a doubling of CO2) ranging from 1.9C to 11.5C (take your pick!) when they varied only six out of many more parameters necessary to model clouds. Their result confirms my point that clouds are still too difficult to model and that climate models underlying the Kyoto Protocol have never been validated.
Scientists have long pointed to a disparity that showed the atmosphere's lowest layer, the troposphere, had not warmed as much as the surface - contrary to greenhouse theory and model results. Christy concludes that the disparity still exists (Item # 2). The Economist (Item #3) explains well the corrections made to the balloon data, but does poorly on the satellite data - finally drawing the wrong conclusions. Surprisingly, Ron Bailey in Reason (Item #4) buys into the story that the disparity between surface and atmosphere is now settled.- and so does Pat Michaels, as quoted by CATO Institute. In the NY Times (Aug. 11), however, Andy Revkin gives a factual and fair account of the three papers and wisely does not editorialize.
I have an idea why the MW value is higher - and why even the lower
0.12 C trend value of CS may be too high. Needs more work before we can
go public. So remember the old saying about operas: "It ain't over
until the fat lady sings."
The Adam Smith Institute (London) explodes the myth that Americans are the world's greatest polluters (Item #4). And Dan Lewis in the WSJ reports that Europe is finding it difficult --and costly - to meet the mandates of Kyoto (Item #6).
Finally, a Science article (5 Aug, pp 883 -885) reports that
people living in certain places where natural radiation levels are 100
to 400 times the normal US background level "do not appear to suffer
any adverse health effects"
bur in some cases "appear
to be even healthier and to live longer" Hormesis anyone?
In one of a trio of new global warming papers in Science Express, Mears & Wentz (2005) address what they consider to be a large source of uncertainty in our (University of Alabama in Huntsville, "UAH") satellite estimate for global lower tropospheric ("LT") temperature trends since 1979. The satellite measurements come from the Microwave Sounding Units (MSUs) and Advanced Microwave Sounding Units (AMSUs) flying on NOAA's polar orbiting weather satellites. The UAH estimate of the globally averaged trend since 1979 to the present has been +0.09 deg. C/decade, considerably below the surface thermometer estimate that has been hovering around +0.20 deg. C/decade for the same period of record.
This discrepancy between the UAH satellite LT trends and the surface thermometer trends has caused some consternation, since what we understand of atmospheric physics suggests that sustained warming at the surface should be amplified with height in the troposphere, not reduced.
Mears & Wentz, who are very capable remote sensing experts from Remote Sensing Systems ("RSS", Santa Rosa, California), found that the LT trend was particularly sensitive to the UAH method for removing the drift of the satellites through the local observing time. The satellites are launched into sun-synchronous orbits that are meant to cross over the same Earth locations at approximately the same time each day. But since the satellites do not have on-board propulsion, the satellites fall slowly back to Earth, which changes their orbital characteristics. In particular, what began as early afternoon observations from the daylight side of the "afternoon satellites" orbits drift to later in the day over the several years of each satellite's lifetime. This causes a spurious cooling trend as the Earth observations are made later in the afternoon to the evening.
The UAH method for removing this drift depended upon the spacecraft roll attitude (the accuracy with which it was pointing straight down, and not sideways) being almost exactly the same during the day side of the orbit as the night side. The new research paper presents Mears & Wentz's own estimate of LT trends using diurnal cycle corrections based upon a climate model estimate of the daily (diurnal) cycle of temperature at different levels in the atmosphere, on a global basis.
Their final estimate of the global lower tropospheric trend through 2004 is +0.19 deg. C/decade, very close to the surface thermometer estimate, and this constitutes the primary news value of their report.
While their criticism of the UAH diurnal cycle adjustment method is somewhat speculative, Mears & Wentz were additionally able to demonstrate to us, privately, that there is an error that arises from our implementation of the UAH technique. This very convincing demonstration, which is based upon simple algebra and was discovered too late to make it into their published report, made it obvious to us that the UAH diurnal correction method had a bias that needed to be corrected.
Since we (UAH) had already been working on a new diurnal adjustment technique, based upon the newer and more powerful AMSUs that have been flying since 1998, we rushed our new method to completion recently, and implemented new corrections. As a result, the UAH global temperature trends for the period 1979 to the present have increased from +0.09 to +0.12 deg. C/decade -- still below the RSS estimate of +0.19 deg. C/decade.
Our new AMSU-based (observed) diurnal cycle adjustments end up being
very similar to RSS's climate model (theoretical) adjustments. So why
the remaining difference between the trends produced by the two groups?
While this needs to be studied further, it looks like the reason is the
same as that determined for the discrepancy in deep-tropospheric satellite
estimates between the two groups: the way in which successive satellites
in the long satellite time series are intercalibrated. There has been
a continuing, honest difference of opinion between UAH and RSS about how
this should best be done.
The third paper (Santer et al, 2005) takes a more thorough look at the theoretical expectation that surface warming should be amplified with height in the troposphere. The authors restate what had already been known: that the UAH satellite warming estimates were at odds with theoretical expectations (as had been some radiosonde measures). Now, the convergence of these newly reported satellite and radiosonde estimates toward the surface warming estimates, if taken at face value, provides better agreement with climate models' explanation of how the climate system behaves.
I only hope that the appearance of these three papers together, with considerable overlapping of authorship, does not represent an attempt to make measurements fit theoretical models. For when this happens, actual measurements can no longer fulfill their critical role in independent validation of climate models. Ideally, measurements would be analyzed with no knowledge of what any given theory predicts they should be.
What will all of this mean for the global warming debate? Probably less than the media spin will make of it. At a minimum, the new reports show that it is indeed possible to analyze different temperature datasets in such a way that they agree with current global warming theory. Nevertheless, all measurements systems have errors (especially for climate trends), and researchers differ in their views of what kinds of errors exist, and how they should be corrected. As pointed out by Santer et al., it is with great difficulty that our present weather measurement systems (thermometers, weather balloons, and satellites) are forced to measure miniscule climate trends. What isn't generally recognized is that the satellite-thermometer difference that has sparked debate in recent years has largely originated over the tropical oceans -- the trends over northern hemispheric land areas, where most people live, have been almost identical.
On the positive side, at least some portion of the disagreement between
satellite and thermometer estimates of global temperature trends has now
been removed. This helps to further shift the global warming debate out
of the realm of "is warming happening?" to "how much has
it warmed, and how much will it warm in the future?". (Equally valid
questions to debate are "how much of the warmth is man-made?",
"is warming necessarily a bad thing?", and "what can we
do about it anyway?"). And this is where the debate should be.
Mears, C.A., and F.J. Wentz, 2005: The effect of diurnal correction on satellite-derived lower tropospheric temperature. August 11, online at http://www.scienceexpress.org.
Santer, B.D., et al., 2005: Amplification of surface temperature trends and variability in the tropical atmosphere. August 11, online at http://www.scienceexpress.org.
Sherwood, S., J. Lanzante, and C. Meyer, 2005: Radiosonde daytime biases
and late 20th century warming. August 11, online at http://www.scienceexpress.org.
Research published this week by Carl Mears and Frank Wentz of Remote Sensing Systems (RSS) in Santa Rosa, Calif., identifies a problem that kept the UAH group from accurately correcting one error caused by NOAA satellites drifting in their orbits over the past 26 years.
The net result of changes in how the data are analyzed added about 0.09
C (about 0.16 degrees Fahrenheit) of global warming over the past 26 years,
with most of that previously unreported warming occurring in the tropics.
Previously, the long-term (December 1978 through July 2005) climate trend in the UAH satellite dataset showed average global warming at the rate of about 0.88 C (about 1.58 degrees Fahrenheit) per century. The new trend, which includes the extra warming in the tropics, shows average global warming at the rate of about 1.23 C (about 2.21 degrees Fahrenheit) per century.
The research published this week by Mears et al includes an RSS satellite dataset showing a long-term warming trend of 1.9 C per century between 1978 and 2003, although that study only included data for the portions of the globe between 70 degrees south latitude (which excludes most of the Antarctic continent and ice shelves) and 82.5 degrees north latitude (near the north shore of Greenland).
When Christy and Spencer ran the UAH dataset for the same sub-global sample and the same time span, they found a long-term warming trend of 0.125 C per decade. The puzzle that Mears and Wentz solved was why climate data gathered by microwave sounding units aboard NOAA satellites agreed less with climate data gathered by balloons in the tropics than it did with balloon data collected in other parts of the globe.
"After we build the datasets we use the balloon data as a way to test the accuracy of the satellite data," Christy said. "To the best of my knowledge, we are the only group to do a rigorous, station-by-station, apples-to-apples comparison of the satellite data to other data collected in the same layer of the atmosphere, instead of trying to compare the satellite data to something artificial, like computer model forecasts."
Station-by-station comparisons assure independence, since there is no method that can be used to adjust the satellite data to match data records from dozens of different locations.
"We've been pleased with the level of agreement between the two datasets, indicating a high degree of consistency," said Dr. Roy Spencer, a principal research scientist at UAH. "Over the years, however, we noticed that the satellite data didn't seem to agree quite as well with balloon data from the tropics as it did with balloon data from other parts of the globe.
"But reliable balloon data from the tropics is scarce and difficult to access, so we couldn't find enough data points to really make a good test. We noted the relative differences in our published datasets, but couldn't explain what might cause those differences."
In a study published this week in the electronic journal "Science Express," the RSS team says the difference was caused by techniques used to correct for orbital drift by satellites that carry the temperature sensors.
These satellites are launched into a pole-to-pole orbit that carries them over the equator at the same local time each day. Over time, however, the satellites tend to drift eastward. Over a period of several years this drift causes each satellite to go over the sunny side of the Earth later and later in the afternoon, so the air temperatures it "sees" are at first warmer and then progressively cooler.
To correct for these false signals, the UAH team developed a technique using parts of the data collected earlier and later in the day.
As each satellite orbits from pole to pole, its temperature sensor spins around a north-south axis every 25 seconds. It takes eleven temperature "snapshots" along a wide west-to-east swath each time that spin turns the sensor toward the Earth's surface.
On the daylight side of the globe that means the first low-angle readings from each spin look westward at a part of the globe that is earlier in the day than the point directly under the satellite, while the last part of each scan looks toward the east at an area that is slightly later in the day.
(Think of a satellite going south-to-north along the Rocky Mountains in the Mountain Time Zone at noon. The first readings on the west side might pick up part of the Pacific Time Zone at 11 a.m., while the last readings on the east might see part of the Central Time Zone at 1 p.m.)
Because air temperature changes through the day -- the diurnal cycle -- Christy and Spencer were able to develop a technique in which they subtracted the differences between the cool temperatures on one side of the satellite from the warm temperatures on the other to determine how much they should correct the data due to orbital drift.
"We didn't take into account the fact that there is a diurnal change between the readings just on each side of the swath, especially in the tropics," Christy said. "That is what the RSS team found, that there are diurnal temperature changes between individual readings on each side of the satellite. We hadn't taken that into account."
The UAH team has now incorporated a diurnal cycle correction from direct satellite readings of the latest, high precision satellite instruments, into the past 26 years of satellite climate data and will provide that updated dataset to the public today. A set of global maps showing 26-year climate trends in both the corrected and uncorrected datasets is available on-line at: http://climate.uah.edu/
"While some people might question the importance of a correction that changes the long term trend by only 0.035 C per decade, for us the most important thing is to produce a climate dataset that is as accurate and reliable as humanly possible," Christy said. "Roy and I would argue that the political debate over climate issues should always be driven by the data, not the other way around."
"It is fairly obvious that some portion of this warming is probably due to human influences," said Spencer. "What isn't clear is how much or which influences."
In addition to rising levels of carbon dioxide, a greenhouse gas, in the atmosphere, other human influences on the climate include deforestation, urbanization, irrigation and the widespread use of chemicals that are or that release powerful greenhouse gases.
"And you have to overlay all of this onto the climate's natural instability," said Christy. "In an environment with so much uncertainty, getting accurate data becomes that much more critical."
In a recent scientific comparison, the UAH team found that the UAH satellite dataset agreed exceptionally well with several long-term temperature datasets prepared by NOAA, the National Centers for Environmental Prediction, the Hadley Centre of the British Meteorology Office, and the European Centre for Medium-Range Forecasts.
The newest satellite dataset correction doesn't reconcile differences between climate trends in the lower layer of the atmosphere and those reported in some surface sensor networks, a major source of controversy since Christy and Spencer published the first satellite-based climate record in 1990.
"The interesting thing is that so much of this warming correction is focused on the tropics, where the long-term warming trend changes by half of a degree Celsius per century," said Christy. "That is a significant amount of additional energy we now see in the tropical atmosphere, but it isn't enough to bring the tropical warming up to what we see on the surface.
"Despite the added warming the 'new' tropical troposphere warming
trend is only half of the warming that is seen at the surface in the tropics,"
he said. "As a general rule, the climate models predict that the
tropical troposphere should be warming 1.3 times faster than whatever
the surface is doing. And it is only in the tropics that the surface and
the troposphere don't seem to follow what the models forecast."
From the MSU-UAH web site ...7 Aug 2005
An artifact of the diurnal correction applied to LT has been discovered by Carl Mears and Frank Wentz (Remote Sensing Systems). This artifact contributed an error term in certain types of diurnal cycles, most notably in the tropics. We have applied a new diurnal correction based on 3 AMSU instruments and call the dataset v5.2. This artifact does not appear in middle troposphere (MT) or lower stratosphere (LS). The new global trend from Dec 1978 to July 2005 is +0.123 C/decade, or +0.035 C/decade warmer than v5.1. This particular error is within the published margin of error for LT of +/- 0.05 C/decade (Christy et al. 2003). We thank Carl and Frank for digging into our procedure and discovering this error. All radiosonde comparisons have been rerun and the agreement is still exceptionally good. There was virtually no impact of this error outside of the tropics.
CLIMATOLOGY is an inexact science at the best of times. Unfortunately it has become, over the past couple of decades, a politically charged one as well. As the debate about global warming - and what, if anything, to do about it - has gathered pace, uncertainties in the data that would be of merely academic interest in other disciplines have acquired enormous practical significance. And one of the most curious uncertainties of all is the apparent discrepancy between what is happening to temperatures at the Earth's surface and what is happening in the troposphere - the lowest layer of the atmosphere, and thus the part that is in contact with that surface.
The troposphere is where most of the air is found and where most of the weather occurs. Computer models predict that, if global warming is really happening, temperatures in the troposphere should rise along with those on the surface. Recorded surface temperatures are, indeed, rising. However, both data from weather balloons and observations made by satellites suggest that temperatures in the troposphere have remained constant since the 1970s. Over the tropics they may even have dropped. This counter-intuitive result has caused sceptics to question how much warming, if any, is actually going on.
The three papers were published in Science. Steven Sherwood is an associate professor at Yale University. Carl Mears and Frank Wentz work for Remote Sensing Systems. Ben Santer is an atmospheric scientist at the Lawrence Livermore National Laboratory.
There are, of course, three possibilities. One is that the sceptics are right. A second is that the models are wrong. And the third is that there is something wrong with the data. Three papers published in this week's issue of Science suggest that the third possibility is the correct one.
Day and night
The first of these studies, conducted by Steven Sherwood of Yale University and his colleagues, examined data from weather balloons. For the past 40 years, weather stations around the world have released these balloons twice a day at the same time-midday and midnight Greenwich Mean Time. Each balloon carries a small, expendable measuring device called a radiosonde that sends back information on atmospheric pressure, humidity and, most importantly for this study, temperature.
Unfortunately, data from radiosondes come with built-in inaccuracies. For example, their thermometers, which are supposed to be measuring the temperature of the air itself (that is, the temperature in the shade) are often exposed to, and thus heated by, the sun's rays. To compensate for this, a correction factor is routinely applied to the raw data. The question is, is that correction factor correct?
Dr Sherwood argues that it is not. In particular, changes in radiosonde design intended to reduce the original problem of over-heating have not always been accommodated by reductions in the correction factors for more recently collected data. Those data have thus been over-corrected, reducing the apparent temperature below the actual temperature.
Dr Sherwood and his colleagues hit on a ruse to test this idea. Because weather stations around the world release their balloons simultaneously, some of the measurements are taken in daylight and some in darkness. By comparing the raw data, the team was able to identify a trend: recorded night-time temperatures in the troposphere (night being the ultimate form of shade) have indeed risen. It is only daytime temperatures that seem to have dropped. Previous work, which has concentrated on average values, failed to highlight this distinction, which seems to have been caused by over-correction of the daytime figures. When the team corrected the erroneous corrections, the result agreed with the models of the troposphere and with records of the surface temperature. The improvement was particularly noticeable in the tropics, an area that had previously appeared to have high surface temperatures but far cooler tropospheric temperatures than had been expected.
The second piece of work looked at satellite measurements of tropospheric temperatures. For the past two decades, microwave detectors, placed on a series of satellites flying in orbits that take them over both poles, have been used to calculate the troposphere's temperature. (Microwaves radiated from the atmosphere contain a host of information about its temperature and humidity.) Here, too, the data are problematic. Because the satellites are looking down through the whole atmosphere, measuring the temperature of the troposphere requires subtracting the effects of the stratosphere-the atmospheric layer above it. But when this has been done, the result suggests, like the over-corrected data from the radiosondes, that the troposphere is cooling down relative to the surface.
However, Carl Mears and Frank Wentz of Remote Sensing Systems, a firm based in Santa Rosa, California, think that this trend, too, is an artifact. It is caused, they believe, because the orbital period of a satellite changes slowly over that satellite's lifetime, as its orbit decays due to friction with the outer reaches of the atmosphere. If due allowance is not made for such changes, spurious long-term trends can appear in the data. Dr Mears and Dr Wentz plugged this observation into a model, and the model suggested that the apparent cooling the satellites had observed is indeed such a spurious trend. Correct for orbital decay and you see not cooling, but warming.
The third paper, by Ben Santer of the Lawrence Livermore National Laboratory in California and his colleagues, argues that it is, indeed, errors in the data that are to blame for disagreements between the predictions of computer models about how the troposphere should behave and what the weather balloons and satellites actually detect. Dr Santer's team compared 19 different computer models. All agreed that the troposphere should be getting warmer. Individual models have their individual faults, of course. But unless all contain some huge, false underlying assumption that is invisible to the world's climatologists, the fact that all of them trend in the same direction reinforces the idea that it is the data which are spurious rather than the models' predictions.
It is, nevertheless, doubtful that these papers will end the matter. Studying the climate is a hard problem for three reasons. The system itself is incredibly complex. There is only one such system, so comparative studies are impossible. And controlled experiments are equally impossible. So there will always be uncertainty and therefore room for dissent. How policymakers treat that dissent is a political question, not a scientific one.
Copyright 2005, The Economist
Anyone still holding onto the idea that there is no global warming ought to hang it up. All data sets-satellite, surface, and balloon-have been pointing to rising global temperatures. In fact, they all have had upward pointing arrows for nearly a decade, but now all of the data sets are in closer agreement due to some adjustments being published in three new articles in Science today.
People who have doubted predictions of catastrophic global warming (and that includes me) have long cited the satellite data series derived by climatologists John Christy and Roy Spencer at the University of Alabama Huntsville (UAH). That data set showed a positive trend of 0.088 degrees centigrade per decade until recently. On a straight line extrapolation that trend implied warming of less than 1.0 degree centigrade by 2100.
A new article in Science by researchers Carl Mears and Frank Wentz from Remote Sensing Systems (RSS) identified a problem with how the satellites drifted over time, so that a slight but spurious cooling trend was introduced into the data. When this drift is taken into account, the temperature trend increases by an additional 0.035 degrees per decade, raising the UAH per-decade increase to 0.123 degrees centigrade. Christy points out that this adjustment is still within his and Spencer's +/- 0.5 margin of error. What's the upshot? Although reluctant to make straight-line extrapolations, Christy notes in an e-mail, "The previous linear extrapolation indicated a temperature of +0.9 C +/- 0.5 C in 2100, the new data indicate a temperature of +1.2 +/- 0.5 C."
However, the Remote Sensing Systems team has made some additional adjustments, such that their global trend is 0.193 degrees per decade. Christy and Spencer disagree with those additional RSS adjustments, but acknowledge that it's an open scientific question which team is correct. If RSS is right, a straight-line extrapolation of future temperature trends implies that global average temperatures in 2100 will be about 2.0 degrees centigrade (3.6 degrees Fahrenheit) warmer than they are today -- more than double the original Christy and Spencer trend. The RSS trend is more in accord with the higher projections of future temperature increases generated by climate computer models.
Is there a way to tell which data set is more accurate? Long term weather balloon data provide an independent measure of temperature trends; however, they also have some problems. Another of the Science articles looks at daytime biases in the radiosonde balloon data sets. A team led by Yale University climate researcher Steven Sherwood, suggests that researchers overcorrected for temperature increases caused by daytime solar heating of the instruments, and thus projected a spurious cooling trend. The researchers acknowledge that there are also nighttime biases, but do not correct for those in this article, coming to the not very robust conclusion that "the uncertainty in the late 20th century radiosonde trends is large enough to accommodate the reported surface warming."
The UAH temperature data set differs from a set of six different recent analyses of weather balloon radiosonde data by range from a low of 0.002 degrees centigrade to a high of 0.023 degrees centigrade. All are well within the +/-0.5 degree margin of error for the adjusted UAH data and lower than the adjusted RSS temperature trend. In other words, the balloon data suggest the global temperature trends are closer to the UAH number than they are to the RSS number. In its article, the RSS team agrees, "Trends from temporally homogenized radiosonde data sets show less warming than our results and are in better agreement with the Christy et al. results."
But what about the future? As the U.S. National Oceanic and Atmospheric Administration notes, "taking into account uncertainty in climate model performance, the IPCC [UN Intergovernmental Panel on Climate Change] projects a global temperature increase of anywhere from 1.4-5.8°C" by 2100.
So what's the bottom line? The UAH team finds warming of 0.123 degrees per decade. The balloon data tend to support the UAH team's findings. The RSS team finds warming of 0.193 degrees per decade. And the surface measurements show a warming trend of 0.15 degrees per decade.
Christy notes, "If you want to say model trends are bolstered, you must remember model trends are all over the map. Which trend is bolstered? Perhaps you want to say those model trends less than 0.2 C per decade are bolstered." Right now the available data sets appear to strengthen the case for arguing that the lower-end model projections for future temperature increases are more likely ones. Christy concludes, "The new warming trend is still well below ideas of dramatic or catastrophic warming."
Ronald Bailey is Reason's science correspondent. His book Liberation Biology: The Moral and Scientific Case for the Biotech Revolution is now available from Prometheus Books.
Copyright 2005, Reason
It seems that for many in the environmental movement, the actual defense of Gaia has taken a back seat to a more important objective; specifically, to attack the capitalist economic system in general, and, in particular, its American exemplar. Interestingly, Greenpeace co-founder Patrick Moore agrees, saying: "The environmental movement has been hijacked by political activists who are using green rhetoric to cloak agendas that have more to do with anti-corporatism and class warfare than with ecology or the environment."
Of course, given the ostensible raison d'être of organizations like Greenpeace and the WWF, attacks upon America can't be couched in blatantly political terms, but must be presented in environmental ones - hence the oft-cited contention that "America is the world's largest polluter". It's common to see the above statement subtly modified into something like "Americans are the world's greatest polluters," a construction that conveniently facilitates the desired demonization of unconcerned, greedy, SUV-driving Americans happily despoiling the air, land and water. In light of the image thus created, it's instructive to examine some actual data.
As far as water pollution is concerned, according to World Bank data on freshwater pollution based on a standard water-treatment test for the presence of organic pollutants, water in the US is significantly less polluted than the worldwide average. In fact, levels of these pollutants in UK rivers and lakes are approximately three times those in the US, which also boasts cleaner water than countries like Denmark, Switzerland, Japan, France and the Netherlands, to name just a few. Odd, given the pernicious presence of "the world's greatest polluters".
With regard to air pollution, the US ranks 114th in the world (first being the worst) with respect to urban sulphur dioxide concentration (the UK figure is about 33% higher), 63rd in ozone-depleting CFC consumption, 45th in urban NO2 concentration, and 13th in NOx emissions per unit of populated land area (the UK value is more than twice as high).
Of course, the greatest concern at present has to do with emissions of so called greenhouse gases. Interestingly, according to recent figures from the United Nations Framework Convention on Climate Change (UNFCCC), the US is not the largest per capita offender here, either. Nor is it second. Among the industrialised nations considered, those positions go to Australia and Canada, respectively. In fact, the average Australian emits some 30% more than his American counterpart (the Canadian figure is only slightly higher than that of the US). Another report (PDF) - which places Canadian per capita emissions at a level just under those of the US, those of Australia again far and away the highest - points out that, when measured per unit of GDP, Australia, Canada, New Zealand, the Czech Republic and Poland are all greater emitters.
I can only attribute the fact that one rarely encounters vituperative attacks on the Australian emissions champions, or on the Canadian runners up, to the political agenda described above.
Finally, in light of the frequently repeated accusation, it's interesting to note that, according to the OECD Working Group on Environmental Information and Outlooks, only two countries (the Netherlands and Austria) spend more than the US on pollution control and abatement (measured as a percentage of GDP).
But don't expect facts like these to be reported by the likes of Greenpeace - they're too busy pursuing anti-capitalist, anti-American agendas of the kind that so disturb their own founder.
The European Union's carbon-trading scheme is a failure on two fronts. It has significantly raised energy costs, and EU CO2 output has almost certainly risen rather than fallen. And this is all before round two of the Kyoto agreement, which calls for even deeper cuts and greater penalties, says Dan Lewis, director of environmental affairs for the Stockholm Network.
Carbon trading made more sense 10 years ago, when natural gas was inexpensive and abundant. For as long as gas cost less than coal, carbon mitigation could be achieved on the cheap. However, as the environmental and economic benefits of gas became clear, a supply bottleneck developed. The result was that last year, throughout Europe, the price of coal fell below that of gas. Because coal typically creates two to three times more carbon dioxide than natural gas, this meant higher emissions, explains Lewis.
o According to a recent research report by UBS, a banking group, CO2 costs are now the key driver of electricity prices on the Continent.
o In Germany, for instance, they are to blame for a 15 percent rise in electricity prices since the start of carbon trading last December, to 39 euros per megawatt-hour (MWh) for 2006 from 34 euros MWh.
o The report also notes that "a further 2 euros to 4 euros per MWh is yet to be priced in."
In the meantime, energy-intensive industries, such as aluminum and steel, are likely to consider closing down plants and relocating outside the EU to countries where emissions compliance costs are lower. Perhaps then a reduction in CO2 would ensue, but at what cost in prosperity and jobs?
What's more, the reduction would only occur in Europe: Emissions would
simply rise in places -- say, China or India -- where those plants relocated.
The overall picture would be unchanged, says Lewis.