Science Behind the Causes of Climate Change

It is generally accepted that climate change is occurring on earth. Based on IPCC observations outline the science behind causes of climate change.

The root cause of change in the earth's climate can be attributed to huge increases in the concentration of so-called 'Greenhouse Gases' in the earth's atmosphere. Since the beginning of the industrial age in the mid-eighteenth century, the exponential growth in technology, wealth, prosperity and ultimately population of the human race has been as a result of our search for, refinement, exploitation and combustion of fossil fuels; coal, oil and gas. A by-product of the burning of these fuels is, among others, Carbon Dioxide [CO2] which is the most common greenhouse gas.

What is a greenhouse gas you might say? First you must understand how the sun's radiation affects the earth. The earth absorbs energy in the form of solar radiation during the day which travels in short waves. At night, the earth cools by emitting this stored energy in the form of infra-red radiation which travels in longer waves. A greenhouse gas is one which is present in the atmosphere and, instead of this infra-red radiation passing through it as it does to smaller molecules i.e. O2, it's larger more flexible molecules soak up the infra-red radiation and re-emit it. The result of this is that some of the infra-red radiation emitted when the earth's surface is cooling is reflected back to onto it by GHGs in the atmosphere. This concept is known as radiative forcing, i.e. there is more energy being soaked up by the earth's surface than being emitted, causing a net increase in surface temperature.

The most common GHGs are: Carbon Dioxide, Nitrous Oxide, Methane and water vapour but there are more. Many of these gases are naturally occurring in nature and under normal circumstances the planet will find a way to reconstitute them in naturally occurring processes e.g. Water condenses and precipitates. Plants photosynthesise; they combine CO2 with water to form oxygen and sugar. However, in the 250+ years since the dawning of the industrial age, the production of these gases has far outweighed the ability of the planet to reprocess them, causing ever higher concentrations in the atmosphere and resulting in a gradual warming of the planet.

This is all pretty bad news on its own, but to compound it we have what is known as the ice-albedo feedback loop. Albedo is the ability of the earth's surface to reflect light. This ability is greatest in polar regions due to the prevalence of ice as this reflects most of the solar energy directed at it (85-90%). Unfortunately, due to rising global temperatures, the ice caps and arctic glaciers have begun to melt at a greater rate, causing more sea to be exposed, which soaks up more solar energy than the ice, which causes an increase in sea temperature, which causes