Question

Plants require carbon dioxide for photosynthesis; despite this, the greater the amount of carbon dioxide released into the atmosphere by various sources (including carbon emissions from vehicles), the worse it is for our biosphere. Discuss 3 reasons why it is detrimental to our planet to have high levels of carbon dioxide emitted continuously into the atmosphere.

Answer 1

Carbon dioxide is not normally considered a pollutant because it is a normal constituent of air. However, excess of carbon dioxide is considered a [pollutant because it leads to adverse effects on the environment. The higher concentration of carbon dioxide in the atmosphere is likely to increase the temperature of the atmosphere. As already discussed carbon dioxide permits the short wavelength visible radiations to pass through it but traps the longer wavelength infra-red radiations (heat waves) reflected by the earth’s surface. This trapping of heat waves causes excessive heating of earth’s atmosphere. This heating effect on earth produced in this way is called GREEN HOUSE EFFECT. The excessive heating of earth and its atmosphere ca have adverse effect on our climate, which will affect all the living beings. The climate will become gradually hot.

According to an estimate, the average temperature of the earth has increased by 10 C in the last 50 years. It is predicted that if the global temperature rises by 3.60 C, the polar ice caps and glaciers would melt. This would increase the water level of oceans by about 100 m and hence lead to the flooding of low-lying coastal areas of the earth.

Greenhouse Gas

Carbon dioxide is a naturally occurring greenhouse gas. Others include water vapor, methane and nitrous oxide. These gases help keep the Earth warm by absorbing the sun's energy and by redirecting energy back to the Earth's surface. An increase in the amount of carbon dioxide creates an overabundance of greenhouse gases that trap additional heat. This trapped heat leads to melting ice caps and rising ocean levels, which cause flooding.

Plants

Plants remove carbon dioxide from the atmosphere in a process called carbon sequestration. The carbon dioxide is stored in biomass then released by the plant. In most cases, the amount released is less than the amount consumed by the plant. Farms, grasslands and forests are considered sources or sinks of carbon dioxide, depending on the practices on these lands. For example, cows produce methane, but grass on the farm sequesters the gas.

Health

Carbon dioxide is essential for the survival of animals. Oxygen is carried to body tissue during breathing and carbon dioxide is released. The gas protects the pH level of blood. Too much carbon dioxide, however, can kill animals. If carbon dioxide is confined, it can decrease the amount of oxygen reaching the body. Any increase or decrease to the amount of carbon dioxide reaching the body can lead to kidney failure or coma.

Sources

Combustible fossil fuels such as coal, power plant gas, oil, vehicles and big industry are the largest source of carbon dioxide. The production is from various items such as iron, steel, cement, natural gas, solid waste combustion, lime, ammonia, limestone, cropland, soda ash, aluminum, petrochemical, titanium and phosphoric acid. Carbon dioxide accounts for nearly 85 percent of all emissions and is produced when natural gas, petroleum and coal are used. The major areas where these fuels are used include electricity generation, transportation, industry and in residential and commercial buildings.