The branch on the left is from a tree in the Black Forest in Germany.What has caused it to change colour and shape?

Learning objectives

• What is acid rain?

• How is acid rain formed?

• What effects does acid rain have on people and the environment?

The Formation of Acid Rain

Burn fossil fuels in

Transport, Industry, Homes, power

stations

The rest reacts with sunlight and ozone in the atmosphere; nitric (HNO3), and sulphuric acid (H2SO4) are produced

Gas, Oil, Coal

Some falls back to Earth close to the source as dry particles, gas and aerosols (NOx and SO2) (dry deposition)

NO2 SO2

It is dissolved in the moisture in the atmosphere making

2H+ and SO42_

and can be carried large distances before falling as rain or snow (wet deposition)

TRANSBOUNDARY POLLUTION

H2O

H+ NO3

_ SO4

2_

Why is acid rain an international issue?

Transboundary deposition

• The countries that are producing the majority of the Pollution that causes acid rain (Britain, Germany, USA) aren’t that badly affected by acid rain.

• Instead, the wind direction means the acid rain falls elsewhere (in Europe this affect Scandinavia; USA affects Canada).

The Result

Acids activate aluminium from the soil which leaches into water and fish die. Drinking water is contaminated

This stand of trees near Most, Czech Republic, has completely died.

Buildings and precious stone objects are weathered away as the stone reacts with the acid

When soil is contaminated, cereal (arable) production drops

Acid Rain – pages 116-117 NKG

1. Which gases cause acid rain and how are they produced?

2. How are these gases carried around the world?3. What is dry deposition?4. How is acid rain formed?5. List the effects of acid rain.6. How have people tried to clean up acid-rain-

affected lakes and forests?7. How could we prevent acid rain?

Extension:Design a cartoon to educate people about causes/effects of acid rain.