Science and the climate: the facts
Part 1 Section 1
The facts about "rising temperatures"
You have said: "We have many advantages in the fight against global warming, but time is not one of them. Instead of idly debating the precise extent of global warming, or the precise timeline of global warming, we need to deal with the central facts of rising temperatures ... Today I'd like to focus on just one [challenge], and among environmental dangers it is surely the most serious of all. Whether we call it ‘climate change' or ‘global warming', in the end we're all left with the same set of facts. The facts of global warming demand our urgent attention, especially in Washington. Good stewardship, prudence, and simple commonsense demand that we act to meet the challenge, and act quickly. ... Across the world average temperatures ... seem to reach new records every few years."
Here, Sir, are the facts about "rising temperatures". The facts which I shall give you in this letter are taken not from my own imagination, nor from the obscurantist reports of the UN's climate panel, nor from any lobby group, but from the peer-reviewed scientific literature.
Very nearly all of the citations that support the crucial facts which your advisers seem not to have put before you, and which I shall set forth in this letter, are from peer-reviewed papers. Some, however, such as the documents of the UN's climate panel, the IPCC, are not peer-reviewed in the accepted sense of the term. Peer-reviewed papers will be indicated by citations with the date in parentheses, thus: Boffin et al. (2008). Papers that are not peer-reviewed will be indicated by square brackets, thus: IPCC .
I begin with a geological and historical perspective on global mean surface temperature that your advisors seem to have withheld from you. For most of the past 600 million years, the mode of temperature - the temperature that most often prevailed globally - is thought to have been 12.5 °F higher than today's temperature: for today's temperature, in the perspective of the long recent history of our planet, is unusually low.
During each of the last four interglacial periods over the past half-million years, temperature was 5 to 8 °F warmer than the present (Petit et al., 1999).
For 2000 years in the Bronze Age, during the Holocene Climate Optimum (which is called an "Optimum" because warmer is better than cooler), temperature was up to 5 °F warmer than the present. Thanks to the warmer weather, on many continents simultaneously, the world's first great civilizations emerged.
It was also warmer during the 600 years of the Graeco-Roman warm period, when the twin civilizations that were the foundation of our own flourished in the Mediterranean. And it was warmer during the half millennium of the Mediaeval Climate Optimum, when the Renaissance reawakened humanity after the Dark Ages, and the great cathedrals and churches of Europe were built.
In 2001 the UN's climate panel made a maladroit and disfiguring attempt [IPCC, 2001] to heighten the baseless alarm that underlies all of its reports by denying that the Middle Ages were warmer than the present. However, three eminent statisticians working at the instigation of your own House of Representatives produced the definitive report [Wegman et al., 2005], confirming the peer-reviewed research of McIntyre & McKitrick (2003, 2005) establishing that the UN's graph had been doctored so as falsely to deny the reality of the mediaeval warm period, to whose existence hundreds of peer-reviewed papers from all parts of the globe attest.
At both Poles, it was warmer only half a century ago than it is today. For temperatures in the Arctic, see Soon et al. (2004). For the Antarctic, see Doran et al. (2002).
During the Maunder Minimum, a period of more than half a century ending in 1700 when there were no sunspots on the surface of our Sun, a Little Ice Age occurred all over the world (Hathaway, 2004). In 1700 there began a recovery in solar activity that has continued ever since, culminating in the 70-year Solar Grand Maximum that seems recently to have ended. During the Grand Maximum, the Sun was more active, and for longer, than during almost any previous similar period in the past 11,400 years (Solanki et al., 2005; and see Usoskin et al., 2003; and Hathaway, 2004). A symposium of the International Astronomical Union  concluded that it is the Sun that was chiefly responsible for the warming of the late 20th century.
From 1700-1998, temperature rose at a near-uniform rate of about 1 °F per century [Akasofu, 2008]. In 1998, "global warming" stopped, and it has not resumed since: indeed, in the past seven years, temperature has been falling at a rate equivalent to as much as 0.7 °F per decade [Hadley Center for Forecasting, 2008; US National Climatic Data Center, 2008]. Very few news media have given any prominence to this long and pronounced downturn in the temperature trend.
It is now thought possible that no new global annual temperature record will be set until at least 2015 (Keenlyside et al., 2008). Yet the projection of the UN's climate panel had been that temperature would rise by about 1 °F during the 17 years to 2015. It is no surprise, then, that Dr. Rajendra Pachauri, the panel's chairman, has called for a re-evaluation of its hitherto very high estimates of "climate sensitivity" - the temperature change in response to the ever-increasing atmospheric concentration of carbon dioxide.
The facts about supposedly "rising temperatures" which I have set out above, can be readily verified by your advisors. If you like, I can assist them in finding the relevant peer-reviewed papers and global temperature datasets. On these facts, there is no scientific basis for your assertion that "We have many advantages in the fight against ‘global warming', but time is not one of them."
Since the world is not warming at the rate projected by the UN's climate panel, it follows that the urgency relentlessly suggested by that panel and echoed in your speech is by no means as great as the UN's reports would have us believe.
The correct question, posed by Akasofu , is this: Since the world has been warming at a uniform rate in parallel with the recovery of solar activity during the 300 years following the Maunder Minimum, and since humankind could not have had any significant influence over global temperature until perhaps 50 years ago, if then, is there any evidence whatsoever that the observed anthropogenic increase in carbon dioxide concentration over the past half-century has had any appreciable influence, at all, on global temperature?
Another relevant question may occur to you: Is it not strange that the "global warming" scare has been rising in the media headlines and in the rhetoric of the classe politique throughout the past seven years, even though global temperature has been falling throughout that period?
Finally, now that you have the facts about temperature before you, it will be evident to you that you were not correct in having said that a new temperature record seems to be set every few years. Despite rapidly-rising carbon dioxide concentrations, there has been no new record year for global temperature in the ten years since 1998; and, in the United States, there has been no new record year for national temperature since 1934 - a record set almost three-quarters of a century ago, and well before humankind could have had any significant influence on temperature.
Part 1 Section 2
The facts about carbon dioxide concentration
You have said: "We know that greenhouse gasses are heavily implicated as a cause of climate change. And we know that among all greenhouse gasses, the worst by far is the carbon-dioxide that results from fossil-fuel combustion."
Sir, the first of your two quoted statements requires heavy qualification: the second is scientifically false. The combined effect of the two statements is profoundly misleading.
Greenhouse gases keep the world warm enough for plant and animal life to thrive. Without them, the Earth would be an ice-planet all of the time rather than some of the time. The existence of greenhouse gases, whether natural or anthropogenic, retains in the atmosphere some 100 Watts per square meter of radiant energy from the Sun (Kiehl & Trenberth, 1997) that would otherwise pass out uninterrupted to space.
According to the UN's climate panel [IPCC, 2007], anthropogenic "radiative forcings" from all sources compared with 1750 account for just 1.6% of this total, or perhaps almost 5% if temperature feedbacks as currently overestimated by the UN are taken into account. I say overestimated because the sum of the UN's high-end estimates of individual temperature feedbacks exceeds the maximum that is possible in the feedback equation used by the UN, implying that the central estimates are also very likely to be excessive. Your words "heavily implicated", therefore, seem somewhat overstated.
As to your second statement, the "worst" greenhouse gas - the one which, through its sheer quantity in the atmosphere, accounts for two-thirds of the 100 Watts per square meter of greenhouse-gas radiative forcing reported by Kiehl & Trenberth (2007, op. cit.) - is water vapor. Carbon dioxide accounts for little more than a quarter.
Two-thirds of the carbon dioxide concentration in the atmosphere is naturally present, and carbon dioxide occupies just one-ten-thousandth more of the atmosphere today than it did 250 years ago (Keeling & Whorf, 2004, updated): for the atmosphere is large and we are small.
The UN's climate panel [IPCC, 2007] thinks that a doubling of carbon dioxide concentration compared with 1750 might occur later this century on current trends, and may lead to a global temperature increase of almost 6 °F. However, numerous papers in the peer-reviewed literature confirm that the UN's central climate-sensitivity projection must be excessive.
Allowing for the fact that the UN's climate panel has exaggerated the effects of temperature feedbacks, the temperature increase in consequence of a doubling of carbon dioxide concentration could be as little as 1 °F. Values as low as this have been suggested in the peer-reviewed literature (e.g. Chylek et al., 2007).
You have proposed, in your speech that three-fifths of the US economy should be closed down by 2060. Do you not think that a far greater degree of scientific certainty as to the effects of minuscule increases in carbon dioxide concentration on temperature would be advisable before strategic damage on any such scale is inflicted upon the US economy from within, and by a Republican?
Part 1 Section 3
The facts about the basis of the imagined scientific "consensus"
You have said: "We stand warned by serious and credible scientists across the world that time is short and the dangers are great."
Sir, the implication of your quoted remark is that the "serious and credible scientists" who are warning us that "time is short and the dangers are great" outnumber the equally "serious and credible scientists" who are not warning us of anything of the kind. The reverse is the case. A recent survey (Schulte, 2008) of 539 peer-reviewed scientific papers published since January 2004 and selected at random using the search term "global climate change" reveals that not a single paper provides any evidence whatsoever that "time is short" or that "the dangers are great".
The notion of imminent, catastrophic climate change is a fiction that is almost wholly absent in the scientific literature. Indeed, the only papers that predict catastrophe are written by a tiny clique of closely-connected, extravagantly-funded, politically-biased scientists with unhealthily close political and financial connections to certain alarmist politicians in the party that you nominally oppose.
Suppose, ad argumentum, that the UN's exaggerated climate-sensitivity estimates, proven in the peer-reviewed literature and in the unfolding temperature record to be fantasies wholly unrelated either to scientific theory or to observed reality, are true. Even then, the disasters imagined by the UN's climate panel and by certain politicians are unlikely to occur. Since the UN's estimates are indeed exaggerations, and are known to be so, the only potentially-"credible" basis for the alarmism reflected in your speech falls away. In the scientific literature, there is no "consensus" whatsoever to the effect that anthropogenic "global warming" will be "catastrophic".
It is vital that you should understand the extent to which the UN's case for panic action is founded not upon theoretical proofs in climatological physics, nor upon real-world experimentation (for nearly all of the parameters necessary to the evaluation of climate sensitivity are not directly measurable, and their values can only be guessed) but upon computer models - in short, upon expensive guesswork.
However, using computer models to predict the climate, even if the input data were known rather than guessed, cannot ever be effective or accurate: for the climate, in the formal, mathematical sense, is chaotic. The late Edward Lorenz (1963), in the landmark paper that founded the branch of mathematics known as chaos theory, proved that long-run climate prediction is impossible unless we can know the initial state of the millions of variables that define the climate object, and know that state to a degree of precision that is and will always be in practice unattainable.
Why is such very great precision necessary? Because it is the common characteristic of any chaotic object, such as the climate, that the slightest perturbation, however minuscule, in the initial value of even one of that object's variables can induce substantial and unpredictable "phase transitions" - sudden changes of state - in the future evolution of the object. Unless the initial state of the object is known to an unattainably high degree of precision, neither the timing of the onset, nor the duration, nor the magnitude of these phase transitions can be predicted at all. Accordingly, the predictions go off track very suddenly and dramatically, but ineluctably.
The UN [IPCC, 2001], accepts that the climate is "a complex, non-linear, chaotic object", and, consequently, that "long-term prediction of climate states is impossible". Yet it then attempts the impossible by making predictions of climate sensitivity that are already being proven exaggerated by the failure of temperatures to rise as the computer models had predicted (or, recently, at all).
All of the climate models relied upon by the UN predict that the distinguishing characteristic or "fingerprint" of anthropogenic greenhouse-gas forcing as opposed to any other forcings is that in the tropical mid-troposphere, about 6 miles up, temperature over the decades should rise at two or even three times the rate of increase observed at the tropical surface. However, this predicted "hot-spot" over the tropics is not observed in any of the tropospheric temperature datasets since reliable measurements were first taken by balloon-borne radiosondes 50 years ago.
Douglass & Knox (2006) and Douglass et al. (2008) have established that the absence of the "hot spot" predicted by the UN's models is real, and is not (as was suggested by Thorne et al., 2007) a measurement error or artifact within the estimated uncertainty interval of the observed record. Lindzen (2008) estimates that in the absence of the "hot-spot" the UN's estimate of climate sensitivity must be divided by at least three. Thus, making this adjustment alone, a doubling of carbon dioxide concentration would raise global temperature not by 6°F but by a harmless and beneficial 2 °F.
You also need to know that the values for climate sensitivity in the computer models - in short, the central estimates of how much the world's temperature will increase in response to a given rise in the concentration of carbon dioxide in the atmosphere - are not outputs from the models, but inputs to them. The computers are being told to assume high climate sensitivity [Akasofu, 2008].
Let me summarize the irremediably shaky basis for the UN's alarmist case. It is not based on physical theory. It is not based on real-world observation. It is based on computer modeling, in which - astonishingly - the models are told at the outset the values for the very quantity (temperature response to increased carbon dioxide concentration) that they are expected to find.
Now you will appreciate how ridiculous it is, to any competent mathematician, to hear the IPCC claiming that it is "90% certain" that most of the observed warming during the 50 years before the warming stopped in 1998 is anthropogenic. For a start, a 90% confidence level is not a recognized statistical interval: 95% confidence, or two standard deviations, is a recognized interval, but that would be even more absurd than trying to claim 90% confidence for a proposition that depends absolutely for its validity upon parameters that cannot be measured and can only be guessed: and a proposition that is demonstrated to be false with each successive year during which no further "global warming" takes place. It is regrettable that anyone should seek to make policy, as you have done, on such a manifestly unsound basis.
Part 1 Section 4
The facts about "rising sea levels"
You have said: "We need to deal with the central facts of ... rising waters."
The "central facts" about "rising" sea levels are as follows.
Sea level has been rising since the end of the last Ice Age 10,000 years ago. It is 400 feet higher now than it was then. The rate of increase has averaged 4 feet per century. Yet in the 20th century, when we are told that "global warming" began to have a major impact on global temperature and hence on sea level, sea level rose by just 8 inches.
That is just one-sixth of the mean centennial rate over the past 10,000 years. Why so little? Because almost all of the world's ice - including the vast sheets that once covered much of what is now the United States - melted away long ago.
True, the UN imagines that most sea-level rise will come not from the melting glaciers about which the media so frequently fantasize, but from thermosteric expansion - sea water swelling as it warms. However, thermosteric expansion can only occur if the body of water in question is getting warmer. The oceans are not getting warmer (except in certain regions, such as the Antarctic Peninsula, where there is evidence of undersea volcanic activity).
Lyman et al. (2006) reported that the oceans of the world had been cooling since 2003. They published a correction the following year, to the effect that the oceans had not been cooling, but had not been warming either.
Now a definitive study based on readings from 6000 bathythermographs, shows that the oceans have indeed been cooling since at least 2003, in line with the atmospheric cooling noted in the observed temperature record.
It is no surprise, then, that the UN's climate panel [IPCC, 2007] has been compelled to cut by one-third its previous high-end estimate [IPCC, 2001] that sea level would rise 3 feet by 2100. Its new high-end estimate is less than 2 feet, with a best estimate of no more than 1 ft 5 in.
The world's foremost expert on sea level is Professor Niklas Moerner, who has been studying nothing but sea level throughout his 30-year career. In a recent paper (Moerner, 2004), he condemns the IPCC for its baseless exaggeration of future sea-level rise, and says there is no reason to suppose that sea level will rise any faster in the 21st century than it did in the 20th - i.e., by about 8 inches.
There is not and has never been any scientific basis for the exaggerated projections by a certain politician that sea level might imminently rise by as much as 20 feet. That politician, in the year in which he circulated a movie containing that projection, bought a $4 million condominium just feet from the ocean at Fisherman's Wharf, San Francisco.
You may well ask whether he actually believed his own prediction and, if so, why he spent so much buying a condominium that - if his prediction were right - would very soon be worthless. In a recent case in the High Court in London, intended to prevent the transmission of alarmist pseudo-science to children, the judge said of this politician that "the Armageddon scenario that he predicts is not based on any scientific view."
Part 1 Section 5
The facts about "receding glaciers"
You have said: "Satellite images reveal a dramatic disappearance of glaciers ... And I've seen some of this evidence up close. A few years ago I traveled to the area of Svalbard, Norway, a group of islands in the Arctic Ocean. I was shown the southernmost point where a glacier had reached twenty years earlier. From there, we had to venture northward up the fjord to see where that same glacier ends today - because all the rest has melted. On a trip to Alaska, I heard about a national park visitor's center that was built to offer a picture-perfect view of a large glacier. Problem is, the glacier is gone. A work of nature that took ages to form had melted away in a matter of decades."
The facts about "receding glaciers" are by no means as "dramatic" as you suggest. You cite evidence from just two glaciers. Even if it were pardonable to deploy anecdotal evidence from a couple of glaciers and then to perpetrate the logical fallacy of arguing from the particular to the general, it is evident that your two examples do not represent a sufficient sample to be credible as a basis for drawing the drastic conclusion that you have drawn.
It may surprise you to learn that there are more than 160,000 glaciers in the world [IPCC, 2001]. Your two examples are a minuscule fraction of one percent of the world's glaciers. Most of these glaciers have never been visited, measured, or analyzed by humankind. The vast majority of them - including the biggest on the planet, which is 250 miles long and 40 miles wide - are in Antarctica, most of which has been cooling for half a century (Doran et al., 2002).
Professor M. I. Bhat, of the Indian Geological Survey, was kind enough last year to communicate to me his results concerning the 9,575 mountain glaciers that debouch from the Himalayan plateau into India. These glaciers, thanks to the British Raj, have been studied and recorded for longer than any others. Professor Bhat reports that most of the glaciers have been receding at a uniform rate since 1880 at the latest. Some of them had begun receding even before this date. His analysis is confirmed on a global scale by Robinson, Robinson & Soon (2007), who report that since 1880 mountain glaciers have receded worldwide at a near-uniform rate, with no appreciable acceleration in the second half of the 20th century, before which time the anthropogenic influence on climate must have been negligible.
Professor Bhat raises the right question: Given that glacial recession began long before humankind could have had any appreciable effect on global temperature, and given that the rate of recession has remained uniform, on what basis can it be said, as you have implied, that it is anthropogenic "global warming" that is causing the glaciers to recede?
The recession of glaciers in the Swiss Alps has revealed mediaeval roadways, forests, and even an entire silver mine that had been buried by ice during the Little Ice Age. The glaciers had not been present in the mediaeval warm period: now they are again absent. There is nothing "dramatic" about this: climate change is indeed real, and has long been occurring for entirely natural reasons. It is far more difficult than the UN's climate panel and certain politicians have suggested to distinguish between natural climatic cycles and any supposed anthropogenic influence in recent decades. And, as you will now appreciate, it is not scientifically credible to state that the Alaskan glacier you mention had taken "ages" to form. Glaciers come and go quite quickly in response to changing climate cycles.
Mount Kilimanjaro has been one of the poster-children for anthropogenic "global warming". A certain politician has publicly suggested that the observed recession of the Furtwangler glacier at the summit - which, he says, may lead to the disappearance of Hemingway's "snows of Kilimanjaro" within a few years - has been caused by anthropogenic "global warming".
However, the scientific facts are remarkably different. As Professor Bhat might say, the right questions that a true scientist rather than a mere politician would ask are these: When did the recession of the glacier begin? And what has been the trend in temperature at the summit of the mountain? The answers are these: the glacier began to recede in 1880, and more than half of the "snows of Kilimanjaro" had already vanished when Hemingway wrote his novel under that title in 1936. Furthermore, since satellite monitoring began in 1970, the surface temperature at the summit has averaged 12.5 °F below freezing, and has never exceeded 3 °F below freezing (Molg et al., 2003). The glacier is not, therefore, melting. It is ablating, not because of "global warming" but because of desiccation of the atmosphere caused by a prolonged and natural regional cooling, compounded by imprudent post-colonial deforestation of the surrounding territory. The High Court judge rightly had harsh words to say about a certain Democrat politician's highly-publicized suggestion that Kilimanjaro had melted because of "global warming".
In the very cold winter of 2007/8, during which the biggest January-to-January fall in global temperatures since records began in 1880 was recorded, several glaciers in Greenland began to re-advance.
Finally, only a tiny proportion of the future sea-level rise imagined by the UN's climate panel is attributed by it to melting glaciers [IPCC, 2007]. It is true that the excitable media reported that melting glaciers would have a very large effect on sea level, but this was because the UN's bureaucrats had inserted into its 2007 report, after the scientists had signed it off, a table in which the estimated contributions to sea-level rise from glaciers and from ice-sheets had each been multiplied by 10, by the simple expedient of moving four decimal points sideways. When I wrote to the UN pointing out this error, the UN quietly corrected, relabeled, and moved the table: but by then it had obtained the alarmist headlines that had been intended: and not one of the newspapers that had printed the incorrect figure bothered to correct it once the UN had been compelled to revise the table. It is episodes such as this that ought to have led you and your advisors to think very carefully about whether the UN's climate panel is as independent, unbiased, science-based, and competent as would be necessary to justify the very drastic damage which you propose to inflict upon the US economy.
Part 1 Section 6
The facts about "disappearing Antarctic ice shelves"
You have said: "Satellite images reveal a dramatic disappearance of ... Antarctic ice shelves."
Eight ice shelves, with a combined area that is less than 2% of the area of Texas, have disintegrated in recent years, and one of them has already re-formed. However, it is significant that all of these ice shelves are concentrated in a single area of Antarctica - the Peninsula - which itself represents only 2% of the total area of Antarctica.
There has been no significant recession of ice shelves anywhere in Antarctica except in the Peninsula, where subsea volcanic activity may have contributed to the observed disintegrations, which are in any event to be expected given that global temperature has been rising for 300 years. In the first 250 of those 300 years, humankind could not by any stretch of the most alarmist imagination be conceived to have had any significant impact on temperature or on melting ice.
It is also significant that the Larsen B ice shelf, which disintegrated suddenly a few years ago, had not been present during the mediaeval warm period (Pudsey et al., 2006). As with the glaciers, so with the ice shelves, all we are seeing is a natural cycle in the coming and going of the Earth's ice. Since it was warmer than the present throughout most of the past 10,000 years, it is likely that at many times there has been less ice at either Pole than there is today.
An interesting recent example is the case of what the alarmist clique calls "Warming Island" - a peninsula in northern Greenland that recently turned out to be an island when a small ice shelf joining it to the mainland melted. The news about "Warming Island" flashed around the world, and various news media carried front-page headlines about this latest alleged evidence for "global warming". Setting aside the consideration - which cannot be too often repeated - that the fact of warming tells us nothing of its cause, one methodical researcher decided to see whether there were any earlier maps that showed "Warming Island" to be an island. The researcher did not even have to go back as far as the mediaeval warm period. In fact, he had only to go back to 1957, when a book published by an Arctic explorer plainly showed "Warming Island" as an island. You will recall that in the 1940s the Arctic was warmer than it is today. Therefore "Warming Island was then an island, and was still visibly an island when the explorer made his map in the late 1950s. Then a natural cooling cycle supervened, and "Warming Island" became what we might call "Cooling Peninsula". Now it is "Warming Island" again.
On the evidence, therefore, the satellite images of disappearing ice shelves do not provide any scientific basis for assuming that the warming that caused the disintegrations was other than local; or that it was caused by anthropogenic rather than solar or volcanic warming; or that the ice shelves that disintegrated had always been present until the recent disintegration. In short, these disintegrations provide no basis whatsoever for the drastic policies that you have proposed to remedy what is on any view a non-problem.
Part 1 Section 7
The facts about "melting polar ice sheets"
You have said: "Satellite images reveal a dramatic disappearance of ... polar ice sheets."
Here, Sir, are the facts about "melting polar ice sheets". There are four great polar ice sheets: the East and West Antarctic ice sheets; the Greenland ice sheet; and the Arctic ice-cap. We shall consider each in turn.
The East Antarctic ice sheet is on a high plateau at high latitude. Since most of Antarctica has cooled over the past 50 years (Doran et al., 2002), so much so that environmental damage caused by cold has occurred in some of the Antarctic glens, there is no danger of this ice sheet disappearing, and there are no satellite images revealing that it has done so, is doing so, or is about to do so.
The West Antarctic ice sheet is grounded below today's sea level. From time to time, therefore, the warmer ocean around it causes sometimes very large pieces of the edge of the ice sheet to disintegrate. However, these edges tend to re-form in the long Antarctic winter. Logs kept by whalers going back hundreds of years record flat-topped icebergs - inferentially, pieces of the West Antarctic ice sheet - many hundreds of miles long. So there is nothing new in these occasional breakages from the edge of the ice sheet. They have happened before; they have happened again; and they tell us nothing about whether or to what extent the warming (whether natural or anthropogenic) that ceased in 1998 was or is responsible. We know, however, that both the summer and the winter extent of the sea ice surrounding Antarctica was greater in 2007/8 than at any time since the satellite record began 30 years ago. Therefore the West Antarctic ice sheet gives no ground for alarm.
The Greenland ice sheet, like that of East Antarctica, is on a high plateau. Also, that plateau is ringed by mountains: for the enormous weight of the ice sheet has borne down heavily on the rock below to create a basin in which the bulk of the ice sheet sits. That is why recent alarmist stories about "moulins" - summer meltwaters getting below the ice sheet and lubricating it so as to allow it suddenly to rush down to the sea - are entirely baseless.
Such moulins are not new: they have often been recorded in the past, and they are a normal part of the Greenland summer climate. Some glaciers debouching from the plateau through gaps in the ring of mountains that surrounds it have indeed receded: recently, however, others have advanced. In late May 2008, in south-western Greenland, one would normally have expected spring flowers: however, the snow still lay thick on the ground.
But the most telling evidence of all is that of Johannesen et al. (2005), who used satellite interferometry to determine that the mean thickness of the Greenland ice sheet increased by 2 inches per year - a total of 1 ft 8 in - during the decade 1993-2003. Once again, there is no cause for alarm.
The last time the Greenland ice sheet melted was 850,000 years ago: and that melting, of course, occurred entirely through natural causes. The UN's climate panel [IPCC, 2007] says that if the Greenland ice sheet melts again, it will only do so if global temperature was sustained at 4 °F above today's for several millennia. Even then, according to the UN, the cause of any such disintegration would be natural rather than anthropogenic.
Part 1 Section 8
The facts about "reduced snowpack"
You have said: "Our scientists have also seen and measured reduced snowpack, with earlier runoffs in the Pacific Northwest and elsewhere."
The facts about "reduced snowpack" are not as you have been led to think they are. Once again, after some three centuries of gradual warming, one would certainly expect to see less rather than more snow cover in the Northern Hemisphere. That would not be surprising. Yet, even if it were so, the fact of the warming that caused the reduction in snow cover would tell us nothing of the cause. However, there has been no reduction in overall snow cover in the Northern Hemisphere in the 30 years since satellites were first able to measure its extent.
Your advisors needed to go no further than the Rutgers University Snow and Ice Lab, which has monitored snow cover in the Northern Hemisphere in the vital winter months for 30 years. During that time, there has been no trend in winter snow cover. There has been no decline at all, either in any individual winter month or at all. Indeed, new records for the extent of Northern-Hemisphere winter snow cover were established in 2001-2 and again in 2007-8, the winter immediately before your speech.
There is, therefore, no scientific basis for the notion that there has been any downtrend in snow cover during the past 30 years. Since natural climate change occurs on regional as well as hemispheric or global scales, there will be some regions with more snow cover and others with less from time to time. But to focus only on those regions with less snow cover, and then to argue from the particular to the general as you have done, drawing the improper implicit conclusion that anthropogenic "global warming" has caused a decline in snow cover, is not only a fallacy of logic but also lacks any scientific foundation in the observed record.
Part 1 Section 9
The facts about "sustained drought"
You have said: "We have seen sustained drought in the Southwest ... In the years ahead, we are likely to see reduced water supplies ..."
The facts about "sustained drought" are these. The atmosphere has been warming for 300 years, as the activity of the Sun has increased from the Maunder Minimum that ended in 1700 towards the Grand Maximum of the past 70 years, during which solar activity was greater than at almost any previous similar period in the past 11,400 years (Solanki et al., 2004; and see Usoskin et al., 2003, and Hathaway, 2004). One of the few proven results in climatological physics is the Clausius-Clapeyron relation, which establishes that, as the space occupied by the atmosphere warms, so its carrying capacity for water vapor increases near-exponentially. The UN's climate panel calls this phenomenon the "water-vapor feedback".
Over a sufficient timescale of decades, then, a warmer climate will entail not a drier atmosphere but a moister one. Sure enough, some of the world's driest regions - such as the southern Sahara - have experienced more, not less, precipitation over the period of the satellite record. The Sahara - contrary to the alarmist claims of a certain Democrat politician - has actually shrunk in area by 300,000 square kilometers over the past 30 years, allowing nomadic tribes to return to regions that they had not occupied within living memory (Nicholson, 1998, 2001).
As to your suggestion that "we are likely to see reduced water supplies", you have yet again blamed "global warming" for a problem that has nothing to do with warmer weather. As the human population expands, its demands on water supplies increase, leading to shortages. That, and not "global warming", is why many parts of the world do not have regular supplies of drinking water.
You may have read John Steinbeck's novel, The Grapes of Wrath. It is set in the Great Plains of the 1930s, and its theme is the prolonged and devastating droughts that occurred in the first half of the 20th century but have been absent in the generally warmer and moister climate since.
Once again, therefore, you have argued from the particular to the general when there was no logical or scientific basis for having done so.
Part 1 Section 10
The facts about "extreme weather events"
You have said: "We have seen a higher incidence of extreme weather events ... We are likely to see ... a greater intensity in storms. Each one of these consequences of climate change will require policies to protect our citizens, especially those most vulnerable to violent weather."
Here are the facts about "extreme weather events". The UN's climate panel has said, and said repeatedly, that it is not scientifically possible to attribute any extreme-weather event to anthropogenic "global warming". The most extreme of all extreme-weather events is the hurricane, tropical cyclone, or typhoon. However, there has been no trend in the frequency of hurricanes that make landfall on the eastern seaboard of the United States for a century, even though global mean surface temperatures rose by more than 1 °F during that century. Furthermore, in the past 30 years the frequency of severe tropical cyclones and of severe typhoons has exhibited a pronounced downtrend.
It has long been settled science that a warmer climate would reduce the frequency and intensity of severe storms outside the tropics. Until recently, a minority of dissenting scientists had held that "global warming" might intensify not the frequency but the intensity of hurricanes, tropical cyclones, and typhoons in the region of the Equator. However, it is now known that warmer weather reduces the temperature differential between the Equator and the Poles; and that wind-shear tends to dampen the intensity of the worst hurricanes.
Two prominent dissenters - notably Emanual (2008) - have resiled in recent weeks from their previously-published opinions to the effect that the intensity of hurricanes might be expected to increase with warmer worldwide weather. There is, therefore, no longer any credible, scientific basis for your implicit conclusion that "a higher incidence of extreme-weather events" has occurred because of anthropogenic "global warming", for three reasons: first, there has been no increase in extreme-weather events in the observed record; secondly, it is not possible to attribute any individual extreme-weather event to anthropogenic "global warming"; and thirdly, for the past ten years there has been no "global warming", so that, even if there had been "a higher incidence of extreme-weather events", which there has not, "global warming" (whether natural or anthropogenic) cannot possibly have been the cause.
Part 1 Section 11
The facts about "sudden changes" in animal habits and habitats
You have said: "In the frozen wilds of Alaska, the Arctic, Antarctic, and elsewhere, wildlife biologists have noted sudden changes in animal migration patterns, a loss of their habitat..."
The facts about "sudden changes" in animal habits and habitats are not as you have implied. First, since the climate has always changed naturally (it is, after all, a chaotic object in mathematical terms), animals are constantly having to change their migration patterns, or to move to new habitats as old ones disappear. To take one obvious example, sea level has risen 400 feet in just 10,000 years. This rise in sea level occurred naturally. Vast lands that were formerly inhabited by a great variety of land mammals are now underwater, and are inhabited by fish. The North Sea is a good example. It was not there 10,000 years ago, and Britain was joined to Europe.
Secondly, since the fact of the warming that ceased in 1998 tells us nothing of its cause, even where it is possible to attribute significant changes or losses of habitat to warmer weather, and even where such changes or losses are harmful, your implication that the "global warming" that caused these undesirable changes is anthropogenic has no scientific basis.
Thirdly, "global warming" - whether natural or anthropogenic - is by no means the most pressing threat to wildlife. The direct intrusion of humanity into the landscape and seascape is the real danger. Scientifically-unwarrantable tendencies to ascribe every adverse event in the biosphere to "global warming" is actually dangerous to the world's most vulnerable creatures, because it diverts attention and vital resources from the true causes of environmental threats towards the non-problem of anthropogenic "global warming".
Let me take one example - the polar bear, poster-child of the alarmist faction. Acres of print and hours of electronic media coverage have been devoted to the imagined disappearance of the polar bear's habitat - the Arctic ice-cap. A question that ought to have occurred to your advisors is this: How long has the polar bear stalked the Arctic, and has the Arctic ice-cap been there throughout that period? The answer is that polar bears evolved from the land-based brown bear some 200,000 years ago. But 125,000 years ago there was an interglacial period, during which global temperatures - so the ice-core analyses tell us - were about 6 °F warmer than they are today. We may legitimately infer that there was no ice-cap during that interglacial period: yet the polar bears survived. How? Because they are warm-blooded animals and are perfectly capable of surviving on land - such as Greenland, or Siberia, or northern Canada, or Alaska - if there is no Arctic ice-cap.
Therefore, even if it were possible to attribute the disappearance of the Arctic ice-cap to anthropogenic rather than to natural "global warming", it is not scientifically credible to say that the disappearance would in any way threaten the existence of the polar bears. They survived the far higher temperatures of the previous interglacial period: there is no reason to suppose they would not be able to survive this one.
Part 1 Section 12
The facts about "polar bears" responding to "new dangers"
You have said: "You would think that if the polar bears, walruses, and sea birds have the good sense to respond to new conditions and new dangers, then humanity can respond as well."
The facts are that polar bears are not intelligent beings. Accordingly, they act not by a conscious effort of will but by instinct. They cannot display "good sense". By natural selection, as they evolved from the brown bear, their coats became white, they became larger and more resistant to cold, and they migrated northward on to the Arctic ice-cap during their hunting season.
The chief danger to polar bears has nothing whatever to do with "global warming" - indeed, a recent survey (Norris, 2001) for the World Wide Fund for Nature shows that in those parts of the Arctic that have warmed the population of polar bears has increased; in those parts that have neither warmed nor cooled the population is stable; and in those parts that have cooled the population has fallen. Polar bears, like us, are warm-blooded animals, and, like us, they prefer warmer weather. The recent bitterly cold winter in the Arctic drove many starving bears to approach human habitations in the hope of finding food.
The real danger to polar bears is hunting. The chief reason for the increase in their population since the Second World War is that both the hunting of polar bears and the culling of the seals on which they feed have been subjected to legislative control. The protection of polar bears and their food supply has worked, is working, and will continue to work. Once again, you have addressed a non-problem by suggesting that the polar bears are at risk (which they are not) because of anthropogenic "global warming", which will be entirely harmless to them, even if the Arctic ice-cap entirely melts away, as it did 125,000 years ago and may well have done during the two-thirds of the past 10,000 years when global temperatures were warmer than they are today.
But the key question is this: Does the polar bear exhibit the key characteristic of a species at risk? Your advisors might have asked that question. And what is the key characteristic of a species at risk? It is, of course, declining population. However, the population of polar bears is not plummeting. Instead, there are five times as many polar bears in the Arctic today than there were in the 1940s. As you may think, that is hardly the profile of a species facing imminent extinction as its habitat shrinks away. Polar bears do not breed on the Arctic ice-cap, but in land-based dens. Though their current staple diet is seal-blubber, their land-based origins are still evident in the fact that their favorite delicacy is blueberries, which do not grow on the Arctic ice-cap, but only on land. Even if the ice-cap vanished, as it has done before, the polar bears would not vanish. There is no scientific basis for your attribution of a non-existent threat of extinction of polar bears to the non-problem of anthropogenic "global warming".
Part 1 Section 13
The facts about "more forest fires"
You have said: "We are likely to see more forest fires than in previous decades ..."
The facts about forest fires are that, yet again, you have attributed to "global warming" a problem that manifestly has another and more obvious cause. We have already established (or, rather, the great physicist Clausius established long ago) that warmer weather means a more humid atmosphere, so that "global warming" is not very likely to cause "more forest fires". The obvious principal cause of forest fires is human activities - such as arson, which has accounted for a significant proportion of all forest fires in the United States in recent years, or accidental discarding of cigarette-butts, or arcing power-lines. It would be cheaper, and hundreds of times more effective, to police the forests more efficiently, to educate the population not to light fires near standing timber during dry weather, and to create fire-breaks even in natural forests so that if fires do start they are easier to control.
Part 1 Section 14
The facts about "changes in crop production"
You have said: "We are likely to see changes in crop production ..."
The facts about crop production are that it is susceptible to changes in the climate, but only if the changes are very substantial. You have only to look at the wide latitudinal distribution of the world's staple crops to appreciate that - even if "global warming" were continuing, which it is not, and even if humans were the cause, which to a great extent we are not - even substantial rises in temperature are not likely to have an adverse effect on crop yields. Indeed, the UN's climate panel says that increases of up to 4 °F would be likely actually to increase crop yields. The astronomer Herschel, in 1801, noticed when reading a table of grain prices in Adam Smith's Wealth of Nations that the price of grain was inversely correlated with the number of sunspots visible on the surface of the Sun. The warmer the weather, the higher the grain yield, and - in accordance with the law of supply and demand - the lower the price. So there is no scientific basis for your implication that "changes in crop production" will be negative, or that any negative changes will be caused by anthropogenic "global warming".
Part 1 Section 15
The facts about "heat waves afflicting our cities"
You have said: "We are likely to see more heat waves afflicting our cities ..."
The facts about "heat waves" are that they can and do occur naturally, and that their frequency is likely to diminish during periods of global cooling, such as the last seven years. Studies of deaths caused by heat waves in Texas and Mexico, which have identical (and hot) climates, show that heat-induced deaths are a function not so much of temperature as of the economic capacity and administrative and medical skill that are available. A heatwave in Mexico can kill thousands: the same heatwave in Texas will kill no one. The United States has the necessary economic strength (which your proposals for shutting down three-fifths of the economy would of course put at risk). And it has the administrative and medical ability. Consequently, it has learned how to deal with heat waves so as to prevent deaths. Therefore there is no scientific basis for saying or implying that anthropogenic "global warming" is or may become the principal cause of death from heat waves. It is lack of economic and social development that causes deaths from heat waves.
Science and the climate: conclusion
Sir, every one of the reasons that you have advanced for alarm and consequent panic action has been demonstrated to be hollow and without any scientific foundation or merit. Yet, if your proposal to close down three-fifths of the economy of the United States is to be justifiable, then not only the false scientific propositions but also the false policy propositions that you have advanced must be shown to be true. Here, then, are ten propositions, with each of which you appear to agree, each of which is actually false. All of these propositions must be proven true before any action is taken to tamper with the climate, still less the fatal, self-inflicted wounds that you would invite your nation to make to her economy:
1. "The scientists, politicians, and media behind ‘global warming' are honest":
They are not;
2. "The debate is over and all credible climate scientists are agreed":
They are not;
3. "Temperature today has risen exceptionally fast, above natural variability":
It has not;
4. "Changes in solar activity do not much impact today's global warming":
5. "Greenhouse-gas increases are the main reason why it is getting warmer":
They are not;
6. "The fingerprint of anthropogenic greenhouse warming is clearly present":
It is absent;
7. "Computer models are accurate enough to predict the climate reliably":
They cannot be;
8. "Global warming is to blame for present and future climate disasters":
It is not;
9. "Mitigating climate change will be cost-effective":
It will not;
10. "Taking precautions, just in case, would be the responsible course":
It would not be.
We have examined the scientific propositions that you have advanced, and found them wanting. We now turn to your policy prescriptions and the basis for them.
Part 2: Public policy and the climate