Preliminary - I have decided to make the following article public, not because I have any particular expertise in this field but because I am quite concerned about the “group think” mentality that attends this issue. Those who are sceptical about the issue are branded “deniers” and there are even those who would deny anyone the right to express an opinion outside the mainstream. Indeed, I have myself been hesitant to express my scepticism and have reacted by deciding to make this article, written originally in 2015
Debate has raged for more than two decades around the issue first described as “global warming” and which has more recently been renamed “climate change”.
What is this all about?
It is appropriate in considering the dimensions of any climate change to have some sort of benchmark or reference point from which to begin. My reference is a chart titled “Global Land-Ocean Index” prepared for NASA by the Goddard Institute for Space Studies.
A quick glance confirms that there is absolutely no question that there has been a warming trend. But observe the X axis. It is calibrated from roughly minus 0.45C to 0.9C above a long-term baseline of zero, a total range of just 1.35 degrees. A trend line from 1880 to about 1975 would show a rise of just 0.3 degrees over 95 years while a trend line from 1975 to the present would show a rise of approximately 0.7 degrees over 32 years.
While the trend is unmistakeable the obvious question is whether this is some sort of unprecedented shift in temperature or is it within the range of historic variability? It might be prudent to keep this modest increase in global temperatures in mind, especially when considered against the backdrop of known temperature variations in the most recent several centuries.
A closer look at the chart above confirms that from 1880 to 1910 the temperature trend was downward. This was followed by a warming trend from about 1915 to about 1942. Then there was a period of cooling to a period of stability until the earlier 1970’s followed by a warming trend that began in about 1975.
My conclusion is that, with some interruptions, earth has been in a warming phase since about 1910. This has never been in question. Only two points are in question, the matter of causation and whether the degree of warming is anything out of the range of historical variations.
There are two questions that should occur to the thoughtful observer:
Has the observed deviation or variability in temperatures been different in scale or duration to well documented warming periods in the last several centuries?
What is the evidence that the major factor in the recent warming trend has been caused by human activity?
The issue became more controversial when global warming activists began to assert, insistently, that warming was being caused wholly, or at least mainly by human activity; that was “anthropogenic” in nature. That assertion tended to suppress earlier assumptions that changes in climate occur because of natural forces that are, by definition, beyond human power to overcome. The idea that both natural and anthropogenic forces might now be in play is obvious but the advocates of anthropogenic global warming, quite early in the process, attempted to dismiss, or at least to discount the role of natural forces in the most recent warming trend.
To have disregarded the possible influence of natural forces was a foolish tactic on the part of the activists since the historical record confirms that large and significant climate changes have occurred frequently in the past. In some cases, they occurred long before humankind could have had any significant role in either warming or cooling events. For example, the most recent glaciation ended about 12,000 years ago, followed by a series of at least a dozen distinct warmer and cooler periods which, in all but the most recent slight warming, had to be the result solely of natural forces.
This dismissal of recent, well documented events is inexcusable on the part of informed climatologists, but seemingly necessary to avoid the logical arguments that present events may be nothing more than a recurrence of natural events.
The means by which anthropogenic forces are alleged to be driving global warming have been identified as an increase in the emission of atmospheric gases which have heat trapping characteristics. These gases, identified as carbon dioxide, methane and nitrous oxide, are being spilled into the atmosphere by oil and coal industries and their downstream end users, and by agriculture, more particularly intensive livestock production.
It was with this very basic understanding of the elements of the debate that I became interested in the matter. But I, like many others, did not come upon the issue without some quite natural preconceptions.
Three issues influenced me to the sceptics’ side of the debate. But first, let us be clear about what the “sceptics” are sceptical about. If there is a sceptic about recent warming, that person clearly doesn’t know how to read a thermometer or has failed to check the irrefutable and undisputed evidence and can rightly be branded a “denier”. But the scepticism I, and most sceptics hold is all about the two questions posed above. It is a healthy and necessary scepticism about whether recent warming is anything unusual in an historical context and whether human activity is in any significant degree a causal agent of the most recent warming trend.
The first of these influences was my interest in and knowledge of earth’s deep and recent history. Insofar as recent history is concerned, I mean the last few million years. During the last one million years or so, interval glaciation advances in the northern hemisphere have occurred in regular cycles at approximate 100,000-year intervals. The last four are clearly illustrated below based on data drawn from ice cores. (This is a good point to interject that, as a layman, I am not going to cite references in a pretentious attempt to suggest scientific expertise. I will just depict what is readily available to the layman from many sound science sources.) The graph below displays four periods of generally declining temperatures. They are all interrupted by a relatively rapid rise in temperatures resulting in a short-lived period of higher temperatures before a descending into another period of colder temperatures and renewed glaciation. The similarity of these incidents suggests a cyclical phenomenon that is obviously natural in its origin. A very persuasive, if not yet irrefutable, theory has been advanced to explain these fairly regular cycles. That theory is built upon variations in the eccentricity of Earth’s orbit around the sun now known as the Milankovitch Cycles, whereby the earth’s orbit changes from nearly circular to slightly elliptical in a cyclical fashion over a period of about 100,000 years. This cyclical phenomenon, coupled with changes in the tilt of the axis and the wobble of that tilt, alters the amount of solar energy falling upon the earth, especially in the northern latitudes. The very close fit of these cycles with glaciation cycles is broadly regarded as a reasonable hypothesis, if not a conclusive explanation for the recurrent glaciations.
The illustration below reveals something else that is quite arresting; periods of relative cold tend to follow a very long and declining trend followed by a rapid and steep warming trend that lasts only about 10,000 to 12,000 years. Earth has now been in the most recent warming period for approximately 12,000 years. Does this suggest that another period of glaciation lies ahead?
The second influence that prompted my scepticism was the readily available history of intermittent warm and cold cycles within the present interglaciation. Since the last glaciation, which ended approximately 12-15 thousand years ago, there have been 15 well documented alternating periods of relative warm and cold temperatures. Earth is in the 8th distinct warm period since the last glaciation.[LG1] Fortunately for mankind the warm periods have averaged much longer than the cold periods. Agriculture began its slow development about 9,000 years ago at the start of the Holocene Climate Optimum which lasted for almost 2,000 years. The most recent two such events were the well documented Medieval Warm Period which lasted from about 900 to 1300 AD, at which time the southern part of Greenland and the shores of Newfoundland were briefly populated by the Norse people. During this period Europe thrived and its population doubled.
The Medieval warm period was followed by The Little Ice Age (The Mauder Minimum) that plagued Europe from about 1300 to 1850 AD. This period is well documented in fact and in literature. It is an historical fact that the settlers in Greenland were not able to vacate the island when a cold cycle struck. This was impossible due to sea ice and the settlers merely died out, as they also did in Newfoundland.
But it wasn’t just the historical fact of these alternating periods that fuelled my scepticism. It was also the realization that the advocates of unprecedented climate warming sought, deliberately, to ignore or suppress the evidence of these most recent events in the climate record. It took a pair of Canadians, Ross McKitrick, an Environmental Economist at of the University of Guelph and Geologist Steve McIntyre, to discredit the infamous “Hockey Stick” representation of recent climate trends. The Hockey Stick representation, created by Michael Mann, suppresses both the Medieval Warm Period and the Little Ice Age in the data presented. Had the advocates of anthropomorphic warming advanced the argument that natural cycles do in fact occur but that man-made effects can accentuate these natural effects with potentially deadly consequences, they might have quelled my sceptical instincts and those of many others. But to acknowledge earlier cycles of warmer and colder periods would surely have weakened their claim that current warming was not only unprecedented in its amplitude but was also largely if not totally of anthropogenic origin. They would also have been forced to admit that, at least to date, there is nothing unique or record setting about the current warm period. Such an admission would have seriously weakened their arguments that human activity is now the principal driver of the recent, modest warming trend.
A third and quite decisive factor in re-enforcing my scepticism was that the argument supporting anthropogenic global warming advanced that “the science was settled” and, in a macabre and odious comparison to those who claim the holocaust of World War Two did not occur, climate sceptics were branded as “deniers”. “Settled science” is, of course one of the most obvious of countless oxy-morons. Supposed “settled science” has been unsettled countless times before and since the classic trial and conviction of Galileo in 1633. At that trial, he was forced to declare that the earth was the centre of the universe. Giordano Bruno was burned at the stake in 1600 for challenging the orthodoxy of settled science.
It is facile and essentially self serving to single out such outstanding heretics as Galileo and Bruno as implied evidence that today’s climate sceptics are also likely to be proven right. Both sides of any argument can play that game. That is not my intent. My intent is to assert that it is vastly premature to suggest that, in an issue as complex as climate, the science is anywhere near “settled” and that if sceptics are to be labelled as “deniers” it is incumbent upon those who would so label them to specify exactly what the sceptics are denying in the so called “settled science”.
In fact, there has been much less “science” applied to the issue of climate change by the International Panel on Climate Change (IPCC) than is widely assumed.
The foundation upon which much of the IPCC conclusions are based is not science as such, but an imperfect tool of science called “climate modelling” whereby various variables that are believed to influence climate, such as the concentration of greenhouse gases in the atmosphere, are fed into massive computers and analysed. But anyone familiar with computer modelling knows that one cannot feed raw data into a computer and push the “analyse” button. One must feed in as well the probable or preconceived effects of an increase in CO2 for example, or the effects of water vapour in the atmosphere or myriad other effects. These are the algorithms upon which the model generates its output. Much like a camera the computer gives back the picture it was pointed at. So, in a very real sense the results of the model are preordained by the assumptions fed into the computer. Furthermore, if the effects of a potentially huge influence, like cloud cover or the massive ocean currents are left out of the models, (or if the algorithms relating to such influences are not quite right) the model output is doomed to be wrong because in that case a vacuum is created and the effects of the inputted variables are thereby magnified.
The graph below shows the tangled and erroneous predictions of 90 climate models as compared to actual temperature changes at the surface and in the lower troposphere. One glance at this graph reveals two facts that should destroy the assertion that the science is, or ever will be, “settled”. First is the wide and widening divergence of the many models’ predictions and the second is the fact that virtually all of them overstate actual measurements. These facts clearly illustrate that none of them have yet been anywhere near right and that the cause and effect assumptions fed into big computers could not have been right. I cannot escape the quip that leapt to mind when first I viewed this graph. “O what a tangled web we weave, when first we practice to deceive”.
The biggest variable entered into these models is the increasing level of CO2 concentrations in the atmosphere and their projected impact on warming. CO2 levels have indeed increased rather steadily from about 313 p.p.m. in 1960 to a present level of 400p.p.m. That’s not an insignificant increase but, even if the small rise in temperature can be charged to that increase it has been far less than most of the models projected. In 1960 CO2 constituted 0.0315% of the atmosphere and now represents 0.04% of the atmosphere. Can it be imagined that this increase is the principal driver behind the slight warming that has occurred? Are nature’s systems so fragile that an increase in the concentration of a gas that now makes up only about 400 p.p.m. of the atmosphere could wreak such havoc as has been confidently predicted, but not yet witnessed?
Another perception that occurs naturally to one with an agricultural background is that CO2 is a natural and crucial plant food, as necessary to plants as oxygen is to animals. As should be known to everyone with the slightest knowledge of science, photosynthesis stands at the very crux of life, marshalling the inputs of sunlight and CO2 to stimulate plant growth while releasing oxygen to support animal life. To call a life supporting gas such as CO2 a pollutant at levels necessary to sustain plant growth is alarmingly ignorant. In fact, the science tells us that CO2 concentration in the atmosphere is in the low range necessary to support vigorous plant growth. Agricultural scientists confirm that a sizable proportion of increasing crop yields in recent decades can be attributed to the increased concentration of CO2 in the atmosphere.
Something else that is rarely emphasized during all the clamour about global warming is the degree to which warming has occurred, and is projected to occur in the future. The degree of warming that appears to have occurred by 2014, at the surface and in the troposphere, is slightly less than 0.4 degrees Celsius. Of the 88 models illustrated above only 1 model predicted a lower temperature advance than was actually experienced. Even the erroneous projections are hardly frightening. Suppose that, instead of the alarms that have been raised, a more balanced comment had been made that, “since the beginning of the last century mean annual temperatures at the surface and in the troposphere have varied by no more than 1.4 degrees Celsius. Though completely true, such a statement would hardly be the stuff of galvanizing headlines.
Even though the alleged effect of greenhouse gasses has been vastly overstated in the models there has also been a considerable body of science that contends that increases in CO2 concentrations are the result not the cause of warming, or at least that CO2 increases follow rather than lead a warming trend. This, to a layman, is logical because of the known fact that CO2 is more soluble in cold water than in warm water and that massive volumes of CO2 are stored in the oceans. This being so, a warming of the ocean’s surface caused by (quelle surprise), variations in solar activity would lead to massive de-gassing of CO2 into the atmosphere.
So, the summation of this is that I am not a sceptic or a “denier” about either climate change or even about some degree of warming or cooling. How could anyone who has witnessed minor year over year changes in their own lifetime or who has read about previous warm and cold periods doubt that climate continues to change as it clearly has in the past? What I am sceptical about, even to the point of denial, is that the principal culprit is a modest increase in atmospheric CO2 and a few other minor greenhouse gases.
During this process of studying the issue and being aware of the arguments and evidence on both sides of this enormous global debate, I have been mystified at the ready acceptance, in cult like obeisance, of the prevailing view that catastrophic climate change is already occurring and is almost the sole result of human causation. Equally I am perplexed by the scorn that is heaped upon those who dare question the prevailing view. One almost feels the desire and determination of the activists to control and censure our independent thoughts and opinions.
Recently, in the unusually cold winter of 2014/15, a columnist for a widely read national paper heaped scorn on a nameless person who remarked to her “global warming eh?” as a friendly, and ironic, salutation as she swept snow off of her windshield. The columnist took extreme umbrage, to the point of writing an outraged and sarcastic column that this person would chose one extremely cold day to express even a smidgen of good humoured doubt on the sacred cow of irrefutable global warming. The degree of intolerance of such an innocuous remark is unsettling. Might one suppose the columnist would have been as critical if, six months later, in a sweltering muggy day the same person had ascribed the oppressive heat as proof positive that we were in the grip of global warming? One, myself included, tends not to be critical of remarks, however ill informed, that align with one’s own convictions, or biases. Though this is natural we should be aware of its dangers.
But I am not quite so confident that humanity has not and is not having some effect on our climate. After all there are over 7 billion of us so it would be surprising if there were no discernable impact upon our environment.
But here is where I differ vehemently with the activists and the purveyors of simplistic and one-dimensional solution. To such activists it is always “Them”, rarely “Us” and never “Me”. “Them” or “they” are the profit seeking oil and gas companies, the dreadful tar sands, the offshore oil rigs, the oil tanker owners and the miners, purveyors and burners of coal. It couldn’t possibly be “Us” who fill up our vehicles with fuel and drive about on highways or fly around on business and vacations. Somehow the evil represented by the oil, coal and gas industries becomes transformed into mere harmless necessity when the material ends up in our gas tanks or lighting our homes. We manage this daily segue from evil suppliers to needful consumers because we refuse to accept that, if carboniferous fuels are the villain, certainly we, their end users, are in any way complicit. That is how Al Gore, Naomi Klein, Neil Young, David Suzuki and countless others of the righteous breed rationalize and justify their important services to humanity. One almost wishes that we might experience a short year where our daily dependence on carboniferous fuels were reduced by, say 50%, to experience how life would proceed. Only then might some of us understand that the coal miners, the oil and gas extractors are not pushing their products down our unwilling throats but that we are demanding their ready and constant availability.
All of this would be farce if the consequences were not so serious. In the name of climate change pipelines are stalled and exploration and extraction are restricted here in Canada. At the same time, we import increasing quantities of oil from the Middle East. Uncountable billions are being spent subsidizing unproductive solar and wind powered energy sources that have, to date, supplied only a small fraction of our energy needs. It is already easy to see the harm this has done to the Canadian economy but quite impossible to see any benefit in leaving our resource un-harvested while enriching other nations. All because of an alleged 1.4 degree C variation rise in global temperatures over the past century that does not yet eclipse temperatures in the Medieval Warm Period when European civilization flourished.
I started this column with an attempt to put the whole issue of climate change in perspective by commenting on the very small variations in temperature over the past century or so. I think that sense of perspective remains important and that the reasonable response to such small changes is not to attempt to control them but to adapt to these changes. Agriculturalists have adapted in many ways by breeding crops that thrive in warmer or colder temperatures and that thrive in variations in other conditions such as moisture and soil salinity. If farmers, whose livelihood depend upon weather conditions can adapt so can we all.