Climate Change - The Basics


There has been an increasing amount of public debate in recent years on the issue of climate change. As the effects of increasing overall global temperatures become difficult to ignore, and climatologists raise their voices in warning, more and more people are asking themselves what exactly is climate change and should we be concerned about it. As the COP23 international climate change talks take place, this article will attempt to answer those questions by briefly exploring the basic concept of climate change as described by the vast majority of climatologists.

At its most basic level climate change simply means a change in overall global weather trends.  This change can be brought about by 'natural' and/or 'artificial' means. Natural climate change occurs as a result of events which are not caused by human beings, and some common examples would be an altered amount of solar energy reaching the earth from the sun, or a series of volcanic eruptions. Artificial or 'anthropogenic' climate change occurs as a result of certain human activities such as the large-scale burning of fossil fuels and practicing specific modes of agriculture.

So how does anthropogenic climate change actually 'work'? The reason is that some human activities cause 'greenhouse gasses' to be released into the atmosphere. These gasses, which include water vapour, carbon dioxide (CO2), and methane, create an insulating layer in the planet's lower atmosphere. Meanwhile, solar energy from the sun passes through the atmosphere, hits the Earth's surface, and is reflected away again. The insulating layer of greenhouse gasses prevents some of the reflected energy from passing back out into space, and the result is an increase in global temperature.

Now, a certain amount of naturally occurring greenhouse gasses in the atmosphere is beneficial. Without them, too much of the sun's energy would pass back out through the atmosphere and the planet would be freezing. But climatologists, while not denying that climate change can occur naturally, are warning that the extra greenhouse gasses produced by human activities are already causing problems, and if left unchecked the situation will become ever more dangerous. In addition to the increasing global temperatures they point to the high CO2 levels currently present in our atmosphere. CO2 levels began to rise during the late 18th century with the advent of the Industrial Revolution in Europe, and since the 1950's they have soared dramatically so that presently there is about a third more CO2 in the atmosphere than there has been for at least the past 400,000 years (this is a conservative estimate).

There is often opposition to the idea of anthropogenic climate change. It has become a politicized issue and many people who identify with certain ideologies automatically reject it as implausible, usually claiming that climate change does indeed occur but only due to natural factors. Countering this claim climatologists have investigated the natural causes associated with climate change and have concluded that these are not responsible for the current changes we are seeing. For example, following a small increase in the amount of solar energy hitting the Earth during the early and mid-20th century, there has been a reduction in the amount over the past thirty-five years, and the upper layers of the atmosphere have been cooling rather than warming – i.e. it’s humans heating the planet, not the sun. Similarly, scientists maintain that internal climate cycles such as El Nino do not create temperature increases but rather transfer existing heat from one part of the planet to another. Also, huge companies such as Shell and Exxon who trade in fossil fuels have deliberately funded campaigns of misinformation in order to try to preserve their method of generating profits.

At present at least 97% of published climatologists agree that human activities are almost certainly responsible for climate change and the debate amongst the scientific community isn't about whether humans are playing a part in climate change but rather about how serious the effects of change are going to be. Unless practices such as the large-scale burning of fossil fuels and mass animal-based agriculture are altered to an environmentally-friendly alternative then most scientists are predicting that we are going to have to face a range of catastrophes in the near future. Some of these include rising sea levels (and the subsequent displacement of people and damage to infrastructure in low-lying coastal areas), extreme weather conditions (e.g. heatwaves and droughts in some areas, unprecedented heavy rainfall in others), reduced agricultural yields (in some areas the growing season will be longer due to frost-free winters, but globally there will be an overall decrease in the amount of food produced), damage to marine life due to overly-acidic oceans and seas, and increased competition for food, fuel, and land (and the subsequent conflict that could bring).

Given the amount of scientific support from all over the globe for the concept I find it difficult to believe that, as somebody recently suggested to me, it is a nefarious conspiracy concocted by devious climatologists in order to create jobs for themselves. If anything, hundreds of millions of dollars are flooding to convince us of the opposite. The scientists are offering empirical evidence to support their claims. Assuming that they are correct and considering the severity of the potential consequences if they are, I think it is vital that as many of us as is possible educate ourselves about the subject and take all appropriate action to prevent a dangerous situation from becoming a deadly one.




1. NASA Climate


3. Skeptical Science

4. Real Climate

5. Climate Central

6. NOAA (National Oceanic and Atmospheric Administration)

7. Michael Mann 'Climate Change Explained', from the Rubin Report.

8. 'The Story of Climate Change', featuring Jim Hansen.

9. Kevin Anderson 'Climate Change, What's Next'.