Greenhouse Effect

GREENHOUSE EFFECT

CONTENT

1. Introduction

1.1 Definition of Greenhouse Effect

1.2 History Background

1.3 Why Social Relevance

2. Chemical Significance

2.1 Carbon Dioxide

2.2 Methane

2.3 Nitrous Oxide

2.4 Chlorofluorocarbons

Bibliography

Draft

References

1. Introduction

1.1 Natural Greenhouse Effect [1, 2, 3, 4, 5]

The natural greenhouse effect is the heating of the Earth due to the presence of greenhouse gases. Shorter-wavelength solar radiation from the sun passes through the Earth's atmosphere, and is then absorbed by the surface of the Earth, causing it to warm. Part of this absorbed energy is then reradiated back to the atmosphere as longer-wavelength infrared radiation. Most of this infrared waves is absorbed by the greenhouse gases, thus heating the Earth.

1.2 Enhanced Greenhouse Effect [1, 2, 3, 5, 6]

The increasing concentration of these greenhouse gases have resulted in increased absorption of infrared radiation emitted from the Earth's surface thus increasing the overall temperature of the Earth, creating the enhanced greenhouse effect.

1.3 History Background [1, 4, 7]

The Industrial Revolution brought steam trains and factories that burnt wood or coal to supply energy that was later followed by petrol, diesel and oil as energy sources. Practices of the Industrial Revolution greatly increased the amount of greenhouse gases concentration thus, increasing the amount of heat energy that is trapped in the atmosphere. Therefore, the formulation of the enhanced greenhouse effect is increased.

1.4 Social Relevance [1, 5, 8]

Global warming caused by the greenhouse effect is a concern to society. The problem influences health, agriculture, environment and other aspects. Therefore, it is important to understand this chemical significance of greenhouse gases and its formation to solve these problems.

2. Chemical Significance

2.1 Carbon Dioxide [ 3, 4, 6]

Carbon dioxide (CO2) is a colourless, odourless and non-flammable gas and is the most prominent greenhouse gas in the Earth's atmosphere. Fossil fuel burning and large-scale deforestation causes the increase in CO2.

C + O2 CO2

CH4 + 2O2 CO2 + 2H2O

The concentration of CO2 has increased from 290 ppmv to 380 ppmv after the Industrial Revolution.

Carbon dioxide is on the rise since 1750

2.2 Methane [3, 4, 6]

Methane (CH4) is a colourless, odourless and flammable gas. It is 20 times more powerful than CO2 as a greenhouse gas on a weight to weight basis. Its concentration has increased from 700 ppbv to 1720 ppbv throughout the twentieth century due to fossil fuel mining, agricultural practices and decomposition of organic compounds. CH4 can be destroyed in the atmosphere via reaction with the hydroxyl radical. The mean atmospheric lifetime of CH4 is about 8 years.

CH4 + OH CH3 + H2O

Methane is on the rise since 1750

2.3 Nitrous Oxide (Laughing Gas) [3,4,6]

Nitrous Oxide (N2O) is an odourless gas. It is 200 times more powerful as a greenhouse gas than CO2. The main sources of N2O created by human activity are from agriculture, biomass burning and industrial processes. N2O is destroyed in the stratosphere via photolysis by solar radiation and