Referat Acid rain - air pollution, acidity in lakes, damage to trees and forests

ACID RAIN

I am presenting my speech about ACID RAIN.

1. INTRODUCTION

Acid rain is caused by burning fossil fuels like coal and oil and allowing them to pollute the atmosphere.

This form of pollution is so strong that many trees and lakes are dying, buildings are decaying and, in some cases, people's health is being damaged.

Acid rain is one of many pressures on our environment caused by the modern way of life enjoyed by people in the more industrialized countries.

Modern technolgy has made many people richer, in one way more healthy and more comfortable than ever before.

However, all these benefits depend on our environment, which provides us with everything we need - the air we breathe, the water we drink, and the food we eat, the house in which we live and the school in which we learn.

If we continue to damage the environment, then it will not be able to support us so well.

I will be telling you more about acid rain and how it can damage the environment.

2. AIR POLLUTION

Most air pollution is a result of burning fossil fuels like coal and oil.

These fuels have been formed over thousands of years from dead plants and animals.

When the fuel is burnt, not only is the energy released, but many other chemicals as well, including sulphur and nitrogen that the organic material contained.

This happens in factories, traffic and cities (-->FOIL 1).

These substances are two of the most important ingredients of acid rain.

(Here is a picture you can understand better. --> FOIL 2   -->

'The water pollution cycle')

Das Bild ist leider nicht als Datei möglich !!!

2.1.What happens to air pollution ?

Some of the pollution falls to the ground very quickly, before it is absorbed by moisture. It settles on trees, buildings and lakes, usually in and around the area where it was produced.

This is called 'dry deposition'.

When water evaporates from seas, lakes or land, the moisture is neither acid nor alkaline.

It is neutral.

Natural rainfall has a pH of between 5 and 6 (neutral is pH 7).

It can dissolve rocks and create spectacular landscape,  in a process that takes thousands of years.

The moisture absorbs gases, like carbon dioxide, found in the atmosphere, and becomes a weak acid.

It can dissolve rocks and create spectacular landscape in a few years.

The rest of the pollution can remain in the air for up to a week and is carried long distances by the wind.

During this time, the chemicals react with the moisture in the atmosphere and become dilute sulphuric and nitric acids.

They are ready to become acid rain. They also react with other chemicals in the atmosphere to form pollutants.

Ozone is one of the most dangerous of these, as it damages vegetation.

It also attacks our health (especially babies and old people).

For example: asthma or other breathing problems, heart problems,

In winter, when acid rain falls as snow, the snow collects on the ground, holding on as acids.

In spring, when the snow melts, there is a sudden surge of water which flows across the land into streams and lakes.

The lake becomes more acid water, so fish and plants can die.

2.2. How far can pollution be carried ?

If you look at smoke coming from a chimney, there are very few days in the year when it goes straight up.

Most often, the smoke bends away from the chimney because the air around the chimney is moving.

Even when there appears to be only a slight wind on the ground, higher up it can be much stronger.

The pollution from the chimneys is carried by the wind.

Some of it may stay in the air for a week or more before it is deposited on the ground.

In this time it can travel many kilometres.

Even a gentle wind of 16 kilometres per hour could carry the pollution over 1,600 kilometres in five days.

The longer the pollution stays in the atmosphere, the more chemical composition changes. So the ozone will be greater.

3. ACIDITY IN LAKES

Two of the most popular hobbies in North America and Europe are fishing and swimming in lakes and streams.

The problem is that living fishes in lakes which are full of acid are caught by  those who fish.

Now we buy this fish and we eat it. So we can get some illness because of acidic  fishes.

This water also damages our skin and eyes, especially with babies. Also animals and flora suffer.

There is no drinking-quality water !

In Austria most of the lakes have very good drinking quality  (-+- show Austrian flag).

4. DAMAGE TO TREES AND FORESTS

Today, almost 40 per cent of the forest is dead or dying from acid rain.

Large areas that were forest are now moorland.

This picture shows you how tree areas can be affected by acid rain

(--> FOIL 2).

Trees can get very thin branches and others must die from acid rain.

Trees are very important since they produce fresh air !

5. DAMAGE TO BUILDINGS

If you look at many buildings, especially old ones, you may well notice that the building materials are breaking up. Building materials weather naturally, but over a long period of time, usually many centuries.

Acid rain speeds up the process.

Good examples in Austria are Saint Stephen's Cathedral, the Votiv Cathedral and the City Hall of Vienna (--> pictures, photos).

Acid pollution had corroded the material (copper covering).

Millions of schillings had to be and have to be spent to restore these famous buildings.

But who should pay ? Should it be the taxpayers of Austria or the factories that caused the pollution in the first place ?

Don't criticize others, begin with yourself.

We should provide help for our environment !!!

Thank you for listening.