Acid Rain, Consequences of the Greenhouse Phenomenon

Acid rain

Normally the rainwater has a pH of 5.6 but when the pH of the rain water drops below 5.6, it is described as the acid rain. The main pollutants which cause acid rain are Sulphur dioxides and the nitrogen oxides and are released into the atmosphere by burning of the fossil fuels. Sulphur oxides and the nitrogen oxides are absorbed by the droplets of the water that make up clouds and get chemically converted to the droplet of H₂SO₄and HNO₃respectively. Through the precipitation, these acids reach to the soil and water this is called the wet deposition. The sulphur oxides and the nitrogen oxides may also be absorbed by the wet surface of land or vegetation and get chemically transformed to H₂SO₄ and HNO₃ respectively called the dry deposition i.e acidic particles SO₂ gas and the particles of the sulphate and nitrate salts. The major problems related to the acid rain is that it does not remain confined to the region where the oxides of the sulphur and the nitrogen are emitted. It may fall hundreds of miles from the pollution source. It has been estimated that thunderstorm transports the atmospheric pollutants more than 1000 km away from the point of their origin within 2-4 days.

Acid rain has been observed to cause a number of adverse implications. It increases acidity in the soil threatened human and the aquatic life and destroys the forests and the crops reducing agricultural productivity. Besides, it also corrodes the buildings monuments statues bridges fences and railing etc.

Consequences of the Greenhouse phenomenon

The consequence of the global warming is a serious threat to the people and the existing environment and the species. Some places would get dry and some places will get wet. The consequences of the global warming in the future are as follows

1: Food production

Food productivity could vary considerably increasing in some of the areas and dropping in some of the other areas because of the change in the global distribution of the heat and the precipitation. Water is the limiting factor in the growth of many crops, especially in the dried areas. Computer models have projected drops in the global yield of the key food crops ranging from 30% to 70%.

2: Forests and biodiversity

Rapid climate change would have the severe impact on the natural ecosystems. Forest growth in the temperature and the sub-arctic region would move toward the poles or to the higher altitudes. If the forest could keep up with the rate of the climate change. Large-scale forest dies backs would also cause the mass extinction of species that could not migrate to new areas. Any shifts in the regional climate, cloud threaten many parks wildlife reserves wilderness areas, wetlands, and the coral reefs. and the fish would die due to the temperature increases in lakes and streams.

3: Human health and the weather extremes

A warmer world would affect the human health by disrupting supplies if the food and the fresh water displacing millions of the people and the altering disease patterns in dangerous and in predictable ways. The spread of the tropical climates from the equator would bring malaria encephalitis yellow fever, danger fever and other insect born disease to formerly temperate zones. In warmer, world weather extremes such as prolong heat waves and droughts would become common in many areas.

4: Sea level rise

Water expand as it warms. Decreasing in the density of the water leads to the increase in its volume which causes the level of the sea to rise. In addition melting, glacier and the ice caps contribute to the increasing ocean volume and raising sea level.

Since 1900 the world's average sea level has raised 10-20 cm and now appears to be rising about 2.5 decades. Warming at the poles caused ice sheets and the glaciers to melt even particles. The global sea level would rise even more.

About one-third of the total population and more than a third of the world economics infrastructure are being concentrated in as coastal region and are highly affected by the global warming. Scientist project that even a modest 0.3 meter i.e 1-foot rise in the average sea level would lead to the drastic change in the existing environment.

Positive and negative impacts of greenhouse effect

Greenhouse effects is a natural effect of the atmosphere that traps the heat near the earth surface. Greenhouse effect is possible only due to the presence of the greenhouse gases which are CO₂, CH_4,N₂O, CFCs, water vapor etc. Due to the effects of the greenhouse gases, the living things are present in the earth. As well as the fluctuation of the temperature during day and night is minimum. This type of the minimum fluctuation of the temperature during the day and night causes the survival of the living beings. But, due to the increase in the atmospheric concentration of these gases the average temperature of the lower atmosphere is going to be increased which in real causes the loss of the agricultural products, loss of biodiversity, weather extremes as well as the sea level rise.

Maintenance of the earth heats level

Our atmosphere has many layers. When the heat rays coming from the sun entered to the layers: they are found to have a short wavelength, so that they can penetrate the atmospheric layer and then they reach the earth surface. Now in the earth surface, these types of the rays are trapped and have increased in the length. Some of the rays are trapped while some are reflected. The reflected wave have the longer wavelength by which they could not penetrate and escape out from the earth atmosphere and hence, the greenhouse effect is observed. Due to this region of the greenhouse effect, the heat in the earth atmosphere is maintained. If there is not such effect, then, there would be extremely hot at the day time and extreme cold at the night time. Due to which the temperature differences becomes very high. Thus, by the help of this greenhouse effect, atmosphere maintains the earth heat level.

Cause of the ozone layer depletion

Here, the ozone is a compound that contains their oxygen atom and this ozone is very much important in the stratosphere which acting as a productive radiation shield for the living organism on the earth. The maximum ozone concentration is around 10ppm in the stratosphere at the altitude of 25 to 30 kilometers which is produced by the photochemical reaction.

O₂ +hm (242m) =O + O

O + O2 + M=O₃ + M (increased energy)

Ozone absorbs the ultraviolet radiation light very strongly at the region of 220-330nm.

About 90% of the ozone is found in the stratosphere between roughly 20km to 50 km is commonly called as the ozone layer.

A scientist has discovered that the ozone layer was being attacked by the CFCs chemicals used in the refrigerator, air condition system, cleaning solvents and the aerosol spray. When the CFCs are released into the atmosphere, chlorine-containing chemicals are used to raised and are broken down by the sunlight. The chlorine reacts and destroys ozone molecules up to 10000 per CFCs molecules. The destruction of the ozone reduces the thickness of the ozone layer and hole is formed. This hole is known as the ozone hole.

References:

.S.C., Santee. Environmental Science. India, New Center: New Center Book Agency (P) Ltd, 2004.

Lal, D.S. Climatology, Sharda Pustak Bhawan, Allahabad.(2010)