Global Warming

Everyone knows the importance of preventing global warming, but not everyone knows the effects and causes of it. Nations take part in activities like “Earth Hour” to make the nations and its citizens to be aware of global warming. When nature fights back, nature always wins. When the light produced through nuclear fusion from the sun finally breaks out form the photosphere, the surface of the sun, it takes an estimated 8minute and 19 second journey to reach our earth. That’s when the magic happens. The Earth radiates the radiant energy back into space but greenhouse gasses traps some of it and keeping it in our atmosphere. It’s like a blanket that insulates and traps the heat, and eventually, it just gets warmer and warmer. That is global warming. Greenhouse gasses are not necessarily bad for us. A certain amount of greenhouse gasses is needed to keep our earth warm. There is a delicate balance between too much and too little greenhouse gasses, in which too much or too little would lead to catastrophe.

There is a long list of the causes of Global Warming, but I would highlight three major causes. The three major causes of Global Warming are increase of greenhouse gasses, arctic methane release and ice-albedo feedback.

The most obvious and perhaps famous cause of Global Warming is the release of greenhouse gases, especially the notorious carbon dioxide and methane. These greenhouse gasses occur naturally, but in due to rapid industrialization more greenhouse gasses are being carelessly poured into the atmosphere. Electricity plants are one of the most polluting facilities as they burn coal to produce energy that is being converted into electricity using turbines. Burning coal produces methane, or CH4, which is 20 times better at trapping heat than carbon dioxide. Carbon dioxide is another greenhouse gas that is being produced in large quantities by human activities. Any form of burning would result in the production of carbon dioxide, from the burning of gasoline in a car’s engine; to the burning of trees in Indonesia for land clearance all produce carbon dioxide. One of the largest contributors to carbon dioxide production is cars. Although a car only produces a tiny amount of carbon dioxide, but multiply that by 750 million cars, the figures are staggering. One might ask how greenhouse gasses trap heat in the first place. Well carbon emissions absorb infrared electromagnetic radiation that is being radiated by the sun, and these infrared active molecules like methane and carbon dioxide would vibrate when they absorb infrared radiation. Excessive vibrations of these carbon emissions would then cause energy transfer from kinetic to heat energy, leading to the warming of the earth.

The second contributing factor to global warming is the arctic methane release. There are two types of feedback, positive and negative feedback. Positive feedback is the reintroduction of the output of a system or natural process into the input of that same system. Negative feedback on the other hand is the disruption of the input of a system or natural process by the output of the same system. Arctic methane release is a form of positive feedback. In arctic areas, most dead organic matter are not being decomposed as the low temperature preserves the organic molecules, and they get buried by large deposits of snow, and eventually compresses and freezes into permafrost. With the larger amount of greenhouse gasses in the atmosphere, the temperature rise is starting to melt off the snow deposits, exposing the melting permafrost that would decompose, producing methane. Clathrate breakdown is another from of arctic methane release. Methane clathrates are basically solid ice compounds that trap methane in their crystal structure. Methane clathrates are being melted down by the increase of global temperature, melting it. Another form of arctic methane release is the release of frozen methane from the seabed. Methane given off by decomposed marine organisms is being trapped by deep seas as their great depth creates enough pressure for the methane to solidify. However the warmer temperature is making the oceans lose some of its pressure and the heating effect also makes this methane ice melt off. The release of methane from these three ways would then contribute to the increasing temperature, the cause of these three examples of arctic methane release, causing more methane to be released into the atmosphere.

Another feedback effect also contributes to the problem of global warming. This feedback effect is the ice-albedo feedback. Albedo is the reflecting ability of a particular surface. The ice-albedo feedback is caused by the melting of glacial ice. Fresh snow, old snow, followed by glacial ice is the three best natural reflectors, with the highest albedo index, whereas seawater is the worst natural reflector, with the lowest albedo index. The increasing global temperatures would cause the melting of glacial ice and snow, turning the best natural reflector of radiant energy into the worst natural reflector of radiant energy, seawater. This seawater would then trap more heat energy than before, causing more temperature rise, which would spiral the situation into a deadly vicious cycle. Ice-albedo feedback, unlike arctic methane release, is a strong feedback, which causes much more temperature rise than arctic methane release.

Global warming also comes with many complications. The most obvious is that the warmer temperatures might lead to sea level rise. Warmer temperatures also lead to larger hurricanes and typhoons, and if left unchecked, it might lead to the disruption of the Thermohaline circulation, plunging large areas of the world either into bone chilling winters or scorching droughts.

The most immediate result of global warming is definitely sea level rise. The earth surface is 75% water, and 2% of it is glacial ice. Although this might seem very small, it is not, and if all 2% of water were to melt into seawater, many of today’s coastal and low lying cities like New York, Venice and most of Holland would be underwater. Famous cities like New Orleans, Washington and London are also under the mercy of sea level rise. In Venice, major floods often occur every once per year, but in recent years its frequency went up sharply to once every 6 months and more recently once every month. Venice is a very low lying city which has a network of canals in the city, making it exceptionally prone to flooding. Washington is another low lying city. Washington was reclaimed from a marshland, which means that it is very low laying, and the fact that it is almost at sea level making it very prone to sea level rise too. London is another city that is at the mercy of sea level rise. Although it is not a very low laying city, it has the river Thames running straight through it, and five feet of sea level rise in the ocean would translate to a five feet rise of the river Thames, which would then submerge the city of London.

Rising temperatures also contribute to larger and more intense storms. Warmer waters equate to more intense hurricanes, as hurricanes draw energy from the heat of the ocean. With a warmer ocean, there is more evaporation and thus more upward lift in the surrounding air, which would cause hurricanes to be stronger. The ferocity Hurricane Katrina was suspected to be the result of rising temperatures. A study done by the journal Nature showed that hurricanes and typhoons have grown in intensity and became longer lasting in the past 30 years. These trends remain coherent to the rising global temperatures all around the world.

The worst nightmare for any meteorologist is that the Thermohaline circulation gets disrupted. The Thermohaline circulation is the circulation of cool and warm water in the ocean, and this circulation is what keeps the temperatures around the world rather constant. Currents bring warm waters from the tropical regions to the poles to cool down, and then flow back to the tropical regions to draw out some heat from those equatorial regions. However, rising temperatures might lead to the cool water warming up before reaching warmer areas, which would cause some parts of the world to have severe droughts. Then, the currents of warm water would then block out the paths of the cool water, leaving them circulating around the same area, leading the extremely cold weathers in other areas. This is perhaps the worst case scenario of global warming as it would cause large scale temperature extremes that would lead to mass extinctions.

Global warming is currently the one thing that threatens mankind the most. The technology to prevent global warming from getting worse is there, all the wind turbines, bio fuel, electrical vehicles; they are all there, ready to be used in a large scale. Now, the key is to act wisely, act quickly and act now.