WHAT ARE THE CAUSES OF ACID RAIN?

What are the causes of acid rain

You may think that 'acid rain' is a relatively modern concept, but it was actually first used over 100 years ago to describe worrying conditions in Manchester, England.

However, acid rain is certainly not a new phenomenon brought on by modern industrialization as all rainfall has a certain amount of natural acidity. It is just that pollutants released from industrialization increases this acidity a thousand fold! And don't think it's just rain you need to worry about as acidity can also be present - and be just as damaging - in snow hail, cloud, fog, mist and even airborne dust!

What causes acid rain?

Results of acid rain

Approximately 300 million years ago, huge areas of the Earth were forested. Over time, tress came to the end of their natural life and died. Where they fell, they were gradually transformed into seams of fossil fuels such as coal and oil.

Today we mine and burn fossil fuels in enormous quantities to generate electricity, heat our homes and power our factories. Unfortunately, burning fossil fuels releases releases huge amounts of pollutants - notably sulphur dioxide, nitrogen oxide and hydrocarbons - into the atmosphere.

Once they are in the atmosphere, sulphur dioxide, nitrogen oxide and the hydrocarbons react with sunlight to produce a selection of secondary pollutants such as ozone.

These secondary pollutants react with the sulphur dioxide, nitrogen oxide to form sulphuric-acid and nitric acid in the tiny droplets of water that go to make up our clouds. In this form the acids are carried on the wind to fall as 'acid rain', often great distances away. Today, in spite of growing environmental awareness all around the world (as is the damage caused by acid rain), large scale industrialization is still increasing.

American studies have indicated that even where forests are showing none of the easily visible external signs of acid rain damage, pollution is nevertheless limiting their growth.

For related articles click onto:
HOW DO YOU GET ACID RAIN?
THE EFFECTS OF ACID RAIN