THE CHINGCHOK Hunter

You will struggle to find anyone who has not heard the terms "climate change", "global warming" and "greenhouse effect". Recently, there was a climate change conference in Copenhagen. It was attended by many world leaders, who sadly didn't achieve much in the way of future reductions of carbon emissions. But what exactly is climate change? Let's explore the question.

A warmer world

Global warming (probably more accurately referred to as climate change) is based on findings that global temperatures, on average for the whole planet, are on the rise.

Ironically, due to more moisture being released into the atmosphere because of more evaporation, more precipitation will occur, often in the form of snow, and so global warming can lead to cold areas getting colder.

It also results in wet areas getting wetter, and that is the reason for the many floods in recent years, and dry areas getting dryer, resulting in massive droughts in many parts of Africa, Asia and Australia, where some places have seen the worst droughts on record. Basically, wherever it's not wet, it's dry.

The carbon cycle

There is a natural cycle that balances many elements and compounds on earth. Nitrogen, phosphorus and water are all cycled over time, which maintains a balance of the chemicals in the world. The same is true for carbon.

Carbon dioxide in the atmosphere is taken in by plants for photosynthesis. Animals eat plants, and plants die and decay, all resulting in respiration (which plants also engage in, but their net output of carbon dioxide is less than their intake), thus putting carbon dioxide back into the atmosphere.

The oceans also act as a carbon sink, absorbing carbon dioxide, which is turned into calcium carbonate shells by animals that therefore serve to lock away the carbon. This balance of the carbon taken in by plants and given out by animals and bacteria is in equilibrium.

Upsetting the balance

Over millions of years, plant and animal remains decayed and through millennia of geological processes, the remains became coal, oil and natural gas, commonly referred to as the fossil fuels. The carbon in these fossil fuels was locked away until humans figured out that they made good fuels and raw materials for innumerable applications.

The locked-away carbon, hitherto not part of the present-day cycle, is now being released on a massive scale because billions many humans require so much energy. This is resulting in billions of tonnes of carbon dioxide being added to the atmosphere every year.

Combining the carbon dioxide emitted by burning fossil fuels with the astonishing and saddening deforestation rate, which leads to a reduction in carbon dioxide absorption, unquestionably affects the balance of the cycle. Simply put, there is a major imbalance, and humans are directly responsible.

What is global warming?

The sun bombards us constantly with electromagnetic waves in the form of infrared (IR) heat waves, visible waves that allow us to see in colour, and ultraviolet waves.

Carbon dioxide in the atmosphere forms a barrier of sorts that doesn't let heat (infrared) rays easily leave the earth's atmosphere.

Some of the IR waves enter the atmosphere and are reflected off the earth's surface back into space.

Many IR waves leave the atmosphere, but carbon dioxide and other greenhouse gases reflect some of the IR waves back to earth, a necessary process that allows the atmosphere to remain at a certain temperature.

The problem is that as the amount of carbon dioxide in the atmosphere increases, the amount of IR waves reflected back to earth increases as well, resulting in a gradual increase in temperature. It is known as the greenhouse effect because greenhouses work in a similar way, trapping the heat inside, making the interior warmer.

Although carbon dioxide levels do fluctuate naturally in the atmosphere, the levels now are substantially higher than they have ever been, which invariably must have an effect on the reflected IR waves, and therefore global temperatures.

Results of climate change

The consequences are many, varied and not good. Glaciers are melting, as are the polar ice caps. This situation, if it persists, will result in sea levels rising. As many people live by the coast, there will be millions of refugees.

There will be weather extremes, which we are already seeing, with many violent storms. Dry areas will become dryer and wet areas wetter. The balance of water distribution and availability will be seriously displaced. This imbalance will have a huge impact on agriculture and the world's food supply.

Ecosystems are at risk, which will lead to the extinction of more organisms. There is already evidence of plants (yes, plants) migrating to places normally too cold for them, displacing local plants and destroying ecosystems.

Above all this, there may be an increase or resurgence in certain diseases due to hotter, wetter conditions that are ideal for breeding. Whatever the results of climate change, everyone on the planet will be affected in one way or another.

Is global warming real?

There are many people out there who still deny that humans are having an effect on the world's climate, but I'm not sure how that can be. Many deniers say that people like Al Gore were peddling a message for their own political agendas, but in reality, even if this was the case, so what?

Even if, by some miracle, we aren't damaging the earth, and the effects of our actions are not contributing to global warming, we still have to recognise that the way in which we are treating our planet, and in turn our atmosphere, is appalling and must be having a negative effect.

The human population, as you may have read in my previous article, is spiralling out of control. There are nearly 7 billion of us, and all of us are contributing to the pollution in one way or another.

The number of cars on the roads, the quantity of electricity we use and the amounts of plastics and ethanol being used, are all predominantly from our fossil fuel reserves. When our population was not so great, the level of pollution was not having the same impact, but now that is impossible to say.

There are other greenhouse gases, with methane being a particularly potent one, meaning our farming industry contributes significantly to global warming, but whether you are a believer or not, it is time to change.

The earth cannot continue on this path of pollution and deforestation. It is only sensible that we look for cleaner, more-sustainable ways of living and meeting our energy needs. The earth and the universe provide us with enough examples of clean energy, so let's make the change and leave a cleaner world for our descendants.

Dave Canavan has an MSc in Behavioural Ecology and is the Head of Secondary at Garden International School. Dave is fascinated by science and loves animals, especially the dangerous kind! Contact Dave at davidc@gardenbangkok.com .