This is a short, non-technical guide to the principles of climate change:

We can measure atmospheric temperatures on a daily, monthly and yearly basis using a variety of instruments. Average temperature readings over many years have indicated that temperatures are progressively rising. The global average surface temperature has increased by about 0.6 ± 0.2°C (1.1 ± 0.4°F) since the onset of the Industrial revolution (IPCC 2001).

The mechanism of climate change is well (though not perfectly) understood. There are a multitude of factors that contribute to both heating and cooling effects in the atmosphere. The balance and interplay of these determine whether or not the Earth cools down or heats up over a given period of time. Gases such as carbon dioxide are present in the atmosphere and are known to absorb infrared radiation emitted from the earth's surface. This absorption process prevents heat loss to outer space and thus exerts a blanketing effect on the earth's surface. The term "Green House Gas (GHG)" is merely a name given to any gas that posesses this "blanketing" property. There is (for the most part) unanimous scientific agreement that increasing levels of green house gases in the atmosphere are driving climatic temperature increases.

The Industrial revolution has resulted in billions of tons of coal and oil being burned. Carbon that was once sequestered in the Earth's crust (as oil and coal) has (over the last hundred or so years) been released into the Atmosphere as carbon dioxide. This "combustion" factor alone accounts for an enormous increase in the concentration of atmospheric carbon. Analysis of carbon dioxide bubbles trapped within ice sheets in the South Pole (over many millenia) have shown that the present concentration of carbon dioxide (380 parts per million) is higher now than at any time during the preceeding 650 000 years (when it fluctuated around a mean of 280 parts per million).

A further human aspect of climate change is connected with the process of carbon sequestration. Trees (and other plant life) remove carbon from the air by converting it to wood, bark, sap and other biological materials. Expanding human populations and poor governmental regulations have resulted in a massive world-wide deforestation problem that has disrupted this vital sequestration process. The world's trees are currently estimated to store 283 gigatonnes of carbon, 50% more than there is in the atmosphere. Humanity can ill afford to generate enormous carbon emissions whilst simultaneously destroying the very mechanism that exists to alleviate the problem.