August 19, 2016

The Greenhouse Effect and The Global Warming

2015-10-14 13.06.50The temperatures had been increasing year after year all over the world, causing the global warming. Scientists everywhere on the globe are greatly concerned with that phenomenon. Even some laypersons, like me who took interest, are well aware of the consequences of that condition. The direct impacts of the global warming is evident in the climate changes, and freak weather conditions, such as: heavy rainfall in some places while severe droughts hit others, storms are getting more frequent and stronger, rise in ocean levels due to the expansion of the water, plus the melted ice from the polar regions and other glaciers pouring into the seas and oceans are alarming. It is learnt that the ocean levels had risen over a foot in the past century and if left unchecked it could rise three feet in the next century. If that should happen the erosions of the coastlines, flooding and loss of lives and properties would increase, especially those in the low-lying areas. It is a known fact that until today, our earth is the only planet in the solar system where life can exist. There may be theories of extraterrestrial beings in the outer space, but are not proven as yet. The reason that life can exist on earth is because we are being protected by the greenhouse effect.
The Greenhouse Effect
If there were no greenhouse gases that consist primarily of water vapour (H2O), Carbon dioxide (CO2) and Methane (CH4) to protect the earth would be scorching hot or extremely cold for any form of life to exist. These greenhouse gases absorb some of the infrared rays (IR) from the sun’s energy before they are radiated back into space. The trapped IR caused the earth to get warm and this effect is called the greenhouse effect. It is the greenhouse effect that kept our planet warm, at the global average of 15°C (59°F), suitable for life to flourish. If there is no greenhouse effect, the global average temperature would be about –18°C (0°F). Where as, the other planets in our solar system are deprived of that protective canopy. Thus they are either scorching hot or extremely freezing cold, for any form of life to exist.
So, what is a greenhouse effect? If there is no greenhouse effect protecting our earth, the sun’s energy in the form of sunray striking the earth’s surface would be very intense for any form of life to exist. On the other-hand, if there is a lack of the greenhouse gases—water vapour (H2O), CO2 and CH4 to absorb and retain them, all the sun’s energy striking the earth’s surface would be radiated back into the space, causing extreme reductions in temperature. Extreme colds are also the cause of lifelessness on other planets. The sunray consist of the Ultraviolet rays (UV) and the Infrared rays (IR) other than the visible light. The Ozone layer in our atmosphere filters the UV, so only a very small amount reaches the earth. The IR is absorbed by the CO2 and only some of them are radiated back into the space. The retained IR provides the warmth necessary to support life on earth. This is called the greenhouse effect. With a normal greenhouse effect, the temperatures are naturally regulated to suit the living things on the earth. However, if there is excess of CO2 in the atmosphere, it would trap more IR for longer durations causing the rise in temperatures. Thus if the normal greenhouse effect is disrupted, mostly by human beings, abnormal climate changes would emerge.
I would like to explain briefly, what a greenhouse is, so as to appreciate how the term greenhouse effect came to be used in connexion with the global warming. Some vegetables and tropical plants, which cannot withstand extreme cold climates have to be grown inside glass houses called the greenhouses. The transparent glass permit the sunray to enter the house in the daytime, warming the interior. After the sun sets, the interior of the glass house maintain the warmth as the ground surface inside had absorbed the sun’s energy during the day and emits them at night. This process is evident from the fact that you would find the paved roads and concrete surfaces still warm, long after the sun had set. Just like the greenhouse, that kept its interior warm at a desired temperature, the gases in our atmosphere that produce the same effect are called the greenhouse gases and their effect on the climate is termed the greenhouse effect.
The Global Warming
Since the industrial revolution in the 19th century, the temperatures had been gradually increasing due to the excess of CO2 emissions. Today, we are witnessing significant temperature increase year after year. The increase in CO2 emissions are caused primarily by burning. The industries and the vehicles that burn fossilized fuels, wild fires, slash and burn agricultures and last but not least, extensive deforestations are the main causes of excessive CO2 into our atmosphere. In my previous articles on reforestations, I had emphasized the important roles the trees play in the conservation of the ecosystems. They absorb the CO2 and sequestered it and release the carbon and the Oxygen gas. This process helps in keeping the ecosystems balanced. However, that balance had been interrupted due to the increase in the greenhouse gases, especially the CO2 gas. The gradual increase in temperatures caused the global warming and this in turn triggered the climate change, which is an environmental problem the world is facing today. This climate change is causing the freak weather conditions that we are being exposed to, today.
The Effects of the Climate Change
The increased temperatures are affecting the whole world. These effects are not very serious in the tropics as compared to that of the colder regions. Places in the temperate regions and the tundras are facing the consequences of the global warming more and more, with the passage of time. As I love to watch documentary videos about Alaska, I learned from them the adverse effects the Alaskans are facing today. As most of the native Alaskans lived off the earth—fishing, trapping and hunting, they are now faced with difficulties to lead their traditional ways of life. Due to the global warming, that caused the climate changes, the impacts on the ecosystems are devastating. The behaviours of the animals had changed and their habitats had shifted. The Alaskans who depended on them as their food resources and for their livings, are being gradually deprived of their traditional ways of life. They are finding it difficult to get enough fish and meat for consumption and furs for trading off to earn money for purchasing, or bartering with other necessary commodities. Thus some are resorting to mining and other means to make their livings. Other visible adverse consequences of the climate change are: —the more frequent and stronger storms, excessive melting of the ice glaciers all over the world causing the oceans to rise, excess rainfalls, droughts, unprecedented flooding everywhere, erosions of the coastlines changing the contours significantly, the heat-related deaths and the loss of properties are prevalent.
To control the increasing temperatures and hence the global warming, the rise in temperature needs to be limited. The present climate policy adopted in 2010, limits the temperature rise at 2 degrees Celsius above the pre-industry level. We will have to wait and see what would be the outcome of the United Nations’ Climate Change Conference due to convene in Paris next month. Some are skeptical that the 2°C limit cannot be achieved and believed the climate change is irreversible. However, some are of the opinion that this could be possible, if all the countries participated and adhered to the policy diligently, especially the great emitters of CO2 gases. It will also be necessary to restrict logging and clearing of the forests to give way to the agricultural industries. The conservations of the forests should also be given the priority. Alternative clean fuels, other than the fossilized fuels for industries and vehicles, and the substitutes for wood and char coal for cooking purposes, such as liquid gases and electricity would drastically reduce the CO2 emissions. If hydro-power, wind-power and solar energy are extensively utilized, it would contribute towards the maintenance of a balanced and normal greenhouse effect. Also, growing more trees would benefit us, as the trees absorb the CO2 gas and retain it for a long time while sequestering the gas and release the Carbon matters, which would seep underground and may form fossilized fuels. An interesting fact is, the CO2 helps trees and plants to grow faster by producing nutrients for them, brought about by the photosynthesis process.
As all these adverse effects are brought on by the human beings, they are responsible to control them and restore a normal balance. The governments, organizations, communities, societies and individuals should be aware of, and recognize the adverse effects of the climate change. This factor should be taken into consideration and given priority in planning for the future.


Related posts

Translate »