Expository Essay - Global Warming 2

Discuss on the causes and the consequences of global warming and climate change.  The earth is getting hotter. Over the last few decades, the significant increase in the earth’s temperature has alarmed many, especially environmentalists. And what is this phenomenon that is taking place? Global warming. It refers to the the warming of the globe due to the greenhouse gases that are released into the earth’s atmosphere. It would also result in disastrous consequences if it is not slowed down. Let me begin by discussing the causes of global warming. Scientists have determined that the main cause of global warming is the excessive amounts of  greenhouse gases added to the atmosphere. Greenhouse gases, such as carbon dioxide, accumulate in the atmosphere and trap heat that normally would escape into outer space. This process is known as the greenhouse effect, which is the fundamental cause of global warming. Human activities have contributed a large amount of greenhouse gases. Studies have shown that the top contributor to greenhouse gases in the atmosphere is power stations. Power stations burn fossil fuels or coal in order to produce electricity. However, in the process of doing so, they release harmful gases, such as sulfer dioxide and carbon dioxide which trap heat easily into the air. Next on the list are industrial processes, followed by transportation fuels, agricultural products and residential uses. Let me provide an example of how a simple car contributes largely to the greenhouse effect. Whenever a car burns gas, it produces carbon dioxide and other greenhouse gases. An average car emits half  a ton of greenhouse gases into the air every month. Can you imagine the total amount of greenhouse gases emitted with the millions of cars in the world? It is horrendous. Thus, it is evident that human activities in recent years have

exacerbated global warming excessively, as huge amounts of greenhouse gases have been released into the atmosphere. Deforestation also plays an enormous role in contributing to global warming. Although cutting down trees do not directly release greenhouse gases into the atmosphere, it reduces the amount of carbon dioxide that is being absorbed into the plants. The main greenhouse gas in the world would be carbon dioxide.  Trees photosynthesize in the day, therefore helping to take in carbon dioxide and release oxygen to the atmosphere. This reduces the percentage of greenhouse gases, especially carbon dioxide, in the air. For example, some trees have been growing in tropical rainforests like the Amazon Basin for hundreds of years. They store almost half their weight in carbon . Scientists have found out that due to the intake of carbon dioxide by all the trees in the world, global warming has decreased by 12.5%. At the rate forests and trees are being cut down, the world will start to rapidly heat up. Hence, deforestation indeed contributes largely to global warming. Whether it is deforestation or the releasing of greenhouse gases by cars, global warming is definitely caused by human activities. Due to the sudden increase in the temperature, it has brought about many disastrous consequences which are detrimental not only to the environment, but also to humans. Firstly, global warming would result in an increase in the occurrence of national disasters. As the temperature of the oceans rises, so will the probability of more frequent and stronger hurricanes. This is evident from the strike of Hurricane Katrina in 2005, which was ranked as one of the five most deadly hurricanes in recent history. Other than the increase in hurricanes, there is also the probability of an increase in intensity of droughts and heat waves. Although some parts of Earth will become wetter due to global warming, other areas will

suffer serious droughts and heat waves. Africa will bear the brunt of it the most. Water is already a dangerously rare commodity in Africa, and according to the Intergovernmental Panel on Climate Change, global warming will aggravate the condition, thus increasing the suffering of the people. Another calamity that global warming would cause is the increase of tsunamis. As the temperature increases rapidly, ice caps will begin to melt, thus raising the sea levels. This, together with the plate tectonics plate that collide or slide past each other, would increase the incidences of horrific tsunamis. Take the recent tsunami that struck Sendai in Japan as an example. The devastating tsunami was of 8 metres high and it swept past Sendai, taking all its buildings and people along with it. Most of the effects of anthropogenic global warming will not be good. These effects spell one thing for the countries of the world: economic consequences. For example, the incident of Hurricane Katrina caused a damage of US $91 billion dollars. The recent 2011 tsunami incident at Japan also required the Japan government to spend tens of billions in order to reconstruct buildings and clean up after the mess. Therefore, the economy of the world or countries that are affected would definitely plunder hugely. Global warming would cause polar caps to melt. This is a three-pronged danger. Firstly, when the polar caps melt, it will throw the entire ecosystem out of  balance. Since ice caps contain desalinated water, they will desalinate the ocean when they melt. The desalinization of the gulf current will affect the ocean currents, which regulate temperatures. The stream shutdown or irregularity will cool the area around north-east America and Western Europe. By desalinating the oceans, it would also greatly affect the habitat of the salt water fishes that live there. They would not be able to survive in water with low salt content and will eventually die out. Secondly, the temperature will rise and change the

landscapes in the Arctic Circle, which will endanger several species of animals, such as polar bears. Only the most adaptable will survive. Thirdly, global warming could also increase after all the ice caps have been melted. Ice caps are white in colour and reflect heat off the sun, thus further cooling the earth. With the absence of all the ice caps in the world, a snow ball effect could start, thus aggravating the situation. Hence, it is clear that global warming affects not only us, but also the environment negatively. It causes the increase in natural disasters, economic losses and also the ecosystem to be unbalanced. The fundamental cause of  global warming is nothing else but us, the humans. It is due to human activities that emit greenhouse gases into the atmosphere, thus worsening the current condition. Hence, it is important and rather urgent for us to abstain from our ‘greenhouse actions’ and save the earth before it is too late!