A massive slab of ice the size of the Yukon Territory breaks off of the Antarctic continent and melts, raising the sea level and flooding coastal cities around the world.

A four-month-long heat wave strikes the Canadian wheat belt, desiccates the soil, sets crop yields to zero, and sends the global economy into chaos.

The Saharan desert takes over two-thirds of Africa, leading to socio-political disruption and the breakout of a pan-African war.

What do these three cataclysmic scenarios have in common? They are all associated with what is popularly known as “global warming.”

Following the rise of modern industry and agriculture since the early 1800s, mankind has increasingly been releasing “greenhouse gases” into the atmosphere. Such gases, which are high absorbers of heat, include carbon dioxide (CO2), methane, nitrous oxide, and halocarbons. According to the global warming theory, these greenhouse gases trap heat within the earth’s atmosphere, leading to increased temperatures and calamitous climate change around the world.

Present CO2 levels are 20 per cent greater than the highest values within the last 160,000 years. Methane levels have more than doubled since the late 1700s. Records indicate global average temperature has increased by 0.5ºC within the last 100 years. Still, the question remains: Is global warming scientific truth?

As a climatologist who works in the private sector, I answer in the negative.

First of all, there is no consensus within the climate community that the greenhouse effect is underway, irrespective of what the press proclaims. One hears only one side of the issue simply because the media limelight is dominated by radical organizations like Greenpeace and popularizers such as David Suzuki. The philosophical slant here is, of course, left-liberalism and any countering view is immediately branded as unfounded or preposterous. They insist, almost ecstatically, that the natural environment as a whole is in a continual state of upheaval. This sensationalism, this setting the public mind into thinking that humanity is on the verge of a climatic apocalypse, helps them greatly in the acquisition of government grants. Very rarely are dissenting voices on the issue give a formal platform.

There has been much discussion about the Intergovernmental Panel on Climatic Change with its report and computer model predictions which say that, if current industrial and agricultural activity remains unchecked, the greenhouse effect will radically intensify, resulting in a 0.25º – 0.55ºC increase in temperature per decade for the next millennium. This translates into an overall 3.5ºC increase by the end of the next century.

This view, popularized by the media, is based chiefly on theory, not empirical verification, as will be shown below. Moreover, the IPCC report was written by a small number of scientists strongly favouring state regulation of industry and the environment, and was submitted only to a select number of committees for approval. Ignored in the massive coverage of the IPPC report was the 1995 Leipzig Declaration, in which 130 eminent atmospheric scientists declared that the global warming hypothesis is untenable. Their conclusion is supported by a recent survey of state climatologists in the U.S., which found that most experts deny the notion that global climate has been significantly disturbed by human activities.

Unfortunately, that cesspool of bureaucracy called the United Nations is at it again, with its Kyoto Protocol. This international agreement, signed in Japan in 1997, places severe (some would say ruinous) restrictions on industry, based on the assumption that global warming is already upon us.

The instrumental record does show that the average surface temperature of the earth has increased by approximately 0.5ºC since the 1880s. Yet this is misleading. It is a globally averaged value, not at all indicative of the extremely variable temperature trends that have occurred in regions, let alone specific localities. Some of these regions have grown progressively warmer while others have turned colder. Others have turned humid when predictions said they would become arid.

Furthermore, the recent temperature change of 0.5ºC is insignificant when compared with variations that have occurred over much longer time periods (for hundreds and thousands of years). Temperature data derived from cores extracted from ice sheets and the ocean floor illustrate that the recorded warming over the last century is well within the range of natural climatic variability (as distinct from climate change caused by man). Also, when looking at data acquired from satellite platforms (from space as opposed to surface observations), there is no evidence of a temperature increase at all. Some data indicate cooling.

Another fact which is infrequently noted, and which makes surface observations of temperature highly suspect, is related to what is known as the “urban heat island” effect. Basically, this means densely populated urban areas are warmer than the surrounding countryside. Concrete and asphalt absorb and retain more heat than soil and vegetation land-surfaces, and release this heat more slowly during night. Waste heat from air conditioning also contributes to elevated city temperatures.

Quality control techniques have been developed to try take these facts into account, and to deal with errors in observer measurement. Nevertheless, these techniques are questionable and quite arbitrary. Since most climate data has been gathered from urban research stations, it cannot be said to be truly representative of global temperatures.

Researchers who state these cold hard facts at conferences are scolded by global warming theorists, not because of the persuasiveness of their own data, but because their agenda of government regulation and sway over public opinion would be jeopardized if dissenting voices were given a hearing. Global warming theorists turn the issue into a political controversy instead of looking at it properly, as a scientific debate.

What puts the global warming hypothesis into greatest doubt has to do with the fact that the forecasted increase in temperatures is based mainly on computer model simulations. In other words, they are mainly theoretical, and the data they produce have not been properly corroborated by real-world observations. In a paper with the apt title “Some Coolness Concerning Global Warming” in the Bulletin of the American Meteorological Society, R.S. Linden writes that “alarm rises from … theoretical considerations” and as a result “there is an unusual degree of extremism associated with the issue.”

True, climate models are requisite tools for study. This does not mean, however, that they are exempt from problems. An increase in global temperature does occur in high-CO2 simulations, but calculations for regions (especially important for public policy decision-making) are still highly dubious.

The extent of snow cover and sea ice (the cryosphere), the advance and retreat of glaciers, the formation and decay dates of lake ice – all of these have been utilized to detect the alleged global warming. A popular theory has it that the first signs of warming will be detected in the areal regression of glaciers, snow and sea ice. There is, however, no conclusive figures to show that the current cryospheric regime indicates a warmer climate.

Only satellite data can give accurate information of areal snow and ice extent, but for obvious reasons the record goes back only to the mid-1960s. A recent study using data from one satellite shows a slight diminution in sea ice extent in the Arctic Ocean, though the time period is for a scant 10 years – and, overall, satellite data indicate no statistically significant change in cryospheric coverage.

One alternative might be to consider more qualitative information from coastal monitoring stations on the dates of sea ice break-up and freeze-up. Such data exists back to about 1910 for the Canadian Arctic Archipelago. Statistical analysis on these data indicate no discernible extension in the length of the ice-free season.

Another so-called indicator of global warming is associated with an increase in extreme weather events. A hotter and thus unstable atmosphere will, so goes the conjecture, permit for increased hurricanes, tornadoes, severe thunderstorms, blizzards, flooding, and heat waves. Some studies show an increase in extreme events, but again there is little substantiating evidence.

With more scientists studying climate change, and with modern technology and near-instantaneous global information dissemination, it could be that we are just more cognizant of these phenomena than we were previously. Only recently have extensive station networks been set in place to monitor and systematically archive extreme events. The record of pre-1950 extreme events is certainly not globally representative. Moreover, the seeming increase in meteorological extremes could also be part of natural climate variation and altogether unrelated with a warmer climate. The eminent English climatologist H.H. Lamb has tabulated unusually high occurrences of floods, droughts, and harsh winters during a colder interval in the later medieval era.

Even if the greenhouse effect does develop to the degree predicted, there are other components of the earth system which can work to offset the warming. Oceans, which cover a large surface area of the planet have tremendous thermal capacities. This means they can absorb and store surplus heat produced by human industry for very long periods. Any warming that might be caused would be offset or made negligible as a result.

There are vogues not only in religion and philosophy, but also in science, climatology included. For example, in the 1970s a slight but noticeable decrease in air temperature accompanied by greater snowcover expanses in the Northern Hemisphere led many to believe that an ice age was imminent. The journals were stuffed with papers on glaciation cycles, television documentaries warned of the coming “deep freeze,” and the great snowstorm of 1977 in eastern North America seemed to bear out the dire predictions. But the trend of the 1970s gave way to the trend of the 1980s, and now the earth is said to be hurtling towards a “runaway greenhouse.” From one extreme to the other.