CAUSES OF GREENHOUSE EFFECT

GREENHOUSE EFFECT

The greenhouse effect is a natural process that warms the Earth’s surface. When the Sun’s energy reaches the Earth’s atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases.

Greenhouse gases include water vapour, carbon dioxide, methane, nitrous oxide, ozone and some artificial chemicals such as chlorofluorocarbons (CFCs).

The absorbed energy warms the atmosphere and the surface of the Earth. This process maintains the Earth’s temperature at around 33 degrees Celsius warmer than it would otherwise be, allowing life on Earth to exist.

CAUSES OF THE GREENHOUSE EFFECT

1. Burning of Fossil Fuels: Fossil fuels like coal, oil and natural gas have become an integral part of our life. They are used on large basis to produce electricity and for transportation. When they are burnt, the carbon stored inside them is released which combines with oxygen in the air to create carbon dioxide. With the increase in the population, the number of vehicles have also increased and this has resulted in increase in the pollution in the atmosphere. When these vehicles run, they release carbon dioxide, which is one the main gas responsible for increase in greenhouse effect.

2. Deforestation: Forests hold a major green area on the planet Earth. Plants and trees intake carbon dioxide and release oxygen, through the process of photosynthesis, which is required by humans and animals to survive. Large scale development has resulted in cutting down of trees and forests which has forced people to look for alternate places for living. When the wood is burnt, the stored carbon in converted back into carbon dioxide.

3. Farming: Nitrous oxide is one the greenhouse gas that is used in fertilizer and contributes to greenhouse effect which in turn leads to global warming.

4. Industrial Waste and Landfills: Industries which are involved in cement production, fertilizers, coal mining activities, oil extraction produce harmful greenhouse gases. Also, landfills filled with garbage produce carbon dioxide and methane gas contributing significantly to greenhouse effect.

ADVANTAGES OF GREENHOUSE EFFECT

One of the reasons why our planet is able to sustain life is because of the presence of greenhouse gases and their effect on earth’s atmosphere and human beings. They can be summarized as follows:

·         The greenhouse effect maintains a manageable temperature on the earth’s surface and makes it habitable for humans, plants and animals.

·         The greenhouse gases act as a filter. Unwanted solar energy is sent back to space. Ozone absorbs the harmful ultraviolet rays of the sun. Carbon dioxide and other gases absorb the longer wavelength radiation. Without these greenhouse gases acting as filter, all harmful rays would have been radiated back to the earth’s surface.

·         For ages, humans have used the greenhouse effect to grow plants even if it is not the season for it. Out of season crops are grown by creating a greenhouse effect artificially.

DISADVANTAGES OF GREEN HOUSE EFFECT:

·         Since greenhouse gases helps to maintain the temperature, the primary effect of the increase in greenhouse gases would be on climate. This would mean warmer summers with natural disasters. Hurricanes have become common in recent years.

·         Water level balance of the earth would be destroyed. Polar ice caps would melt leading to an increase in the ocean level. Floods will inundate low lying areas.

·         Marine life and ecosystem would be destroyed. Oceans absorb carbon dioxide thereby affecting the level of alkalinity. Many forms of marine life would be adversely affected if alkalinity increases. Polar ecosystems would be destroyed. In the Arctic, melting polar caps are threatening the habitats of polar bears and penguins.

·         Global warming would also affect the weather pattern. Rainfall would become erratic in many parts of the world. This might eventually lead to desertification.

Overall the impact of increased greenhouse effect on climate and human life would be disastrous. The world community therefore needs to wake up now before it is too late.

see also: causes-and-effects-of-climate-change

EFFECTS OF GREENHOUSE EFFECT

Global warming

Greenhouse gas levels have been increasing since the start of the Industrial Revolution, but over the last few decades growth has been particularly fast. Total greenhouse gas emissions have increased by about 80% since 1970, creating a radiative forcing of 2838 mW/m^2 equivalent to an atmospheric concentration of 473 ppm CO2e.

Ocean Acidification

Increases in carbon dioxide levels have made the world's oceans 30% more acidic since the Industrial Revolution. The ocean serves as a sink for this gas and absorbs about a quarter of human carbon dioxide emissions, which then goes on to react with seawater to form carbonic acid. So as the level of carbon dioxide in the atmosphere rises, the acidification of the oceans increases.

Changes to plant growth and nutrition levels

Since plants need carbon dioxide to grow, if there are higher amounts in the air, plant growth can increase. Experiments where carbon dioxide concentrations were raised by around 50% increased crop growth by around 15%. Higher levels of carbon dioxide makes carbon more available, but plants also need other nutrients (like nitrogen, phosphorus, etc.) to grow and survive. Without increases in those nutrients as well, the nutritional quality of many plants will decrease. In different experiments with elevated carbon dioxide levels, protein concentrations in wheat, rice, barley, and potato tubers, decreased by 5-14%.

Can the greenhouse effect be reversed?

Many scientists agree that the damage to the Earth's atmosphere and climate is past the point of no return or that the damage is near the point of no return. "I agree that we have passed the point of avoiding climate change," Josef Werne, an associate professor at the department of geology & planetary science at the University of Pittsburgh told Live Science. In Werne's opinion, there are three options from this point forward: 

1.     Do nothing and live with the consequences.

2.     Adapt to the changing climate (which includes things like rising sea level and related flooding).

3.     Mitigate the impact of climate change by aggressively enacting policies that actually reduce the concentration of CO2 in the atmosphere.

Keith Peterman, a professor of chemistry at York College of Pennsylvania, and Gregory Foy, an associate professor of chemistry at York College of Pennsylvania, think that the damage isn't to that point yet, and that international agreements and action can save the planet's atmosphere. 

Currently, some scientists are investigating how to re-engineer the atmosphere to reverse global warming. For example, theories published in the journal Science in July 2017 by lrike Lohmann and Blaž Gasparini, researchers at the Institute of Atmospheric and Climate Science at ETH Zurich in Switzerland, proposed reducing cirrus clouds that trap heat. 

"If cirrus clouds behave like a blanket around the Earth, you're trying to get rid of that blanket," Lohmann, a professor of experimental atmospheric physics at ETH Zurich, told Live Science. [Cool the Planet? Geoengineering Is Easier Said Than Done] "You remove the water vapor, you remove the humidity and you prevent the normal cirrus cloud formation," Lohmann said.

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