Global Warming – What Everyone Needs To Know

Jack Oughton

Unless you have been living in a hole for the past decade, or have made serious efforts to avoid breaking news, you’ve probably noticed the words ‘global warming’, and are aware of the controversy they bring and emotions they stir wherever they are spoken. Former presidential candidate Al Gore’s Academy Award winning film An Inconvenient Truth was released in 2006 to a flurry of media activity, taking $49million dollars worldwide at the box office, and seems to be convincing evidence that in this day and age people are starting to take interest in global warming. It follows him in his famous lectures around the world as he tries to raise awareness on climate change. As we know, however, human nature is to disagree on everything, and naturally the film (and it’s message) was criticised. President Bush famously pulled America; one of the world’s largest consumer of resources, out of a treaty that would limit the amount of polluting emissions America could release. When asked if he’d even watch the film, he simply responded “doubt it”.

To simplify the political issues a little; the debate itself is almost an ideological war, a focus point in the battle between liberals and conservatives, Democrat and Republican. The almost clichéd debate between the right to do business and prosper weighed off at the expense of the environment. Not for the first time, political motives succeed in clouding important issues.

The idea that humanity could actually be influencing the climate was not really taken seriously by the scientific community until the 1960s. In 1958 an American Oceanographer, Charles Keeling began long-term measurements of atmospheric carbon dioxide at the Mauna Loa observatory in Hawaii. His research data showed an unmistakable link between the amount of greenhouse gasses in the atmosphere and an increase in global temperature. In the 1820s Jean Baptiste Joseph Fourier discovered that greenhouse gasses (in order of abundance; water vapor, carbon dioxide, methane, nitrous oxide, and ozone) trap heat radiated from the Earth's surface after it has absorbed energy from the sun. This is the greenhouse effect hypothesis. Without it there could be no life on the earth as the temperature would be too cold. However, the burning of ‘fossil fuels’ for energy such as gasoline, coal, and natural gas, mean that this warm blanket may soon become a smothering shroud as an estimated 3.2 billion metric tons of carbon dioxide is added to the atmosphere annually. In 1896 Svente Arrhenius, a Swedish Chemist and Nobel Laureate, showed that doubling the carbon dioxide content of the air would gradually raise global temperatures by 5-6C. Time magazine ran a cover story on the idea of a warming world as long ago as 1939, boldly proclaiming “weathermen have no doubt that the world at least for the time being is growing warmer”.

But what exactly is global warming? Global warming is the process in which the planet’s average air and ocean temperature increases, this means the overall

temperature increases, but individual regions experience more varied temperature fluctuations. Global warming is not new, throughout history the Earth’s temperature has changed significantly in response to periodic natural events and changes. Previous changes have been linked to events such as minor changes in the earth’s orbit and orientation, impacts from large meteors, or from particularly catastrophic volcanic activity, thickening the atmosphere with dust and reducing the earth’s exposure to the sun’s rays. Natural variations in the sun’s output are thought to play their part and even changes in ocean circulation, which can be seen in atmospheric events such as El Nino, which by virtue of an area of the Pacific ocean heating by just 0.5°C, can result in drought in Africa, flooding in South America, and hurricanes in Australasia.

Our climate today is actually a warm interval between colder periods of glaciations; times where ice from the poles covers greater areas of the earth’s surface due to the lower temperature. Striking terrestrial features such as the great lakes in the USA where caused by glaciers expanding and melting in old valleys. Glacial ice melted and refroze in weaknesses in the bedrock, exploiting small weaknesses is a process known as frost action. Glaciers also act like sandpaper on rock, grinding across in the process of abrasion. What most people refer to the last ice age ended 10,000 years ago and coincided with the end of the Palaeolithic period. Around this time the first Civilizations began to form in modern day Iran, and man began to establish itself as the dominant animal species of the planet, taking advantage of a more hospitable climate suited to agriculture and permanent settlement, and the scientific and societal advances this allowed.

Why is global warming important? The effects of global warming are already starting to make themselves known. Our interstellar ‘sister’, Planet Venus is about as accurate a description of Hell as we know. Sulphuric acid rains permanently from a caustic sky, never to reach the bleak surface. On the ground the average temperature is 460 °C, hotter than any oven and enough to melt lead. The atmospheric pressure is 92 times our own, the moisture is acidic enough to corrode and the air itself is utterly poisonous. If by odd circumstance you were to arrive there unprotected, you’d die quickly; crushed, cooked, choked and corroded.In spite of this the planet was once said to be quite similar to our own, how then could it have become a shining example of almost ridiculous hostility to life? The answer lies with global warming. Scientists believe that the planet once had water on it’s surface, but it’s closeness to the sun lead to this water being evaporated over time. As the atmosphere thickened with water vapour, the planet’s temperature continued to increase in a feedback loop, eventually getting so hot that all standing water had evaporated into the atmosphere, a ‘domino effect’.

Though it’s safe to assume that we won’t be enduring Venusian climates any time soon, the main worry is that just a small amount of warming can create.

As mentioned earlier, due to the precise nature of the earth’s climatic system, small changes such as the causes behind El Nino can upset things significantly. In the environmentally aware (DISASTER!) film The Day After Tommorow, the hypothetical (but seriously taken) scenario of the Gulf Stream’s disruption is explored, though possibly with some exaggeration, as the effects are ludicrously apocalyptic (an almost immediate Ice Age, complete with tidal waves, tornadoes, hurricanes…). However, melting of the ice caps could disrupt the flow of the stream, and lower European temperatures by 5°C. Considering the severity of El Nino effects by just a .5°C drop, this is definitely cause for concern.

Then where is the controversy? The controversy arises from the argument that global warming is a natural process, it is obvious that disaster scenarios sell, the film industry has an entire genre based around the idea (see above). Throughout history there are always examples of unfounded media alarmism, recent examples such as SARS; which was hyped as a ‘superbug’, yet had a mortality rate of 9.6%, or the H5N1 bird flu, which despite 5 years of scaremongering, has yet to appear.In 1923, just 16 years before the ominous article in TIME, a front page article in the Chicago Tribune declared: “Scientist Says Arctic Ice Will Wipe Out Canada.” The article quoted a Yale University professor who predicted that large parts of Europe and Asia would be “wiped out” and Switzerland would be “entirely obliterated.”The exploitation of abundant resources by the developing world gives the people of these countries an opportunity to experience the quality of life of the developed world, and who are we, who have spent the last 300 years since the industrial revolution, devastating the planet in our own way, to stop them? Much of their future economic growth will depend directly on the effects of industry and the energy required getting it. For them, it is just not financially viable to use cleaner, but more expensive sources of power, or to enact industrial protocols that would decrease pollution but stifle much needed industrial growth.

What could happen in the future? Scientists using supercomputers to simulate climate change get varied results depending on the figures they input and the models they use, naturally they cannot predict what will happen, but indicate what could happen, with some degree of accuracy. The results they give us are generally grim, the average predicted temperature increase over the next 100 years is around 3 degrees centigrade. This is enough to cause widespread desertification, completely disrupt ecosystems, and flood regions of lower elevation, severe consequences for all life on this planet.

Though nothing is really certain as far as science is concerned, would it not be best to perhaps assume that we need to reduce the impact we are creating upon the planet, to be on the safe side? Despite the hype, the possible consequences for humanity could be dire.

Most would agree that the trade-off of some economic growth against the possible stability of our climate is the only sane thing to do, for how can economies grow if we cannot adapt fast enough to a rapidly changing planet, or at worst if we cannot adapt at all to a planet no longer hospitable to us?

References [ALL ACCESSED 27/02/08]Business and Media Institute; Fire and Ice http://www.businessandmedia.org/specialreports/2006/fireandice/FireandIce.pdf http://www.pbs.org/wgbh/nova/ice/chill.html http://www.guardian.co.uk/environment/2007/jan/08/climatechange.climatechangeenvironment http://www.eia.doe.gov/oiaf/1605/ggccebro/chapter1.html - http://www.skepticalscience.com/climate-change-little-ice-age-medieval-warm-period.htm http://gemini.oscs.montana.edu/~geol445/hyperglac/eroproc1/ http://solarsystem.nasa.gov/planets/profile.cfm?Object=Venus http://www.ghgonline.org/predictions.htm