4.11 Understand the biological consequences of pollution of air by sulfur dioxide and by carbon monoxide.
- The air is being polluted with sulfur dioxide and carbon monoxide.
- This is because humans produce these as waste products in factories etc.
- When in the atmosphere they can dissolve in rain water to create acid rain.
- Acid rain is corrosive and can damage metals and rocks.
- Acid rain can also change the PH in soil or rivers, this means that some species can not survive in that area.
4.12 Understand that water vapour, carbon dioxide, nitrous oxide, methane and
CFCs are greenhouse gases.
Green house gas: a gas that contributes to the greenhouse effect by absorbing infrared radiation.
Green house effect: the trapping of the sun's warmth in a planet's lower atmosphere, due to the greater transparency of the atmosphere to visible radiation from the sun than to infrared radiation emitted from the planet's surface.
In large quantities these gasses can change the climate by keeping in too much heat.
Gasses that do this include: water vapour, carbon dioxide, nitrous oxide, methane and CFCs.
CFC: A compound containing carbon, chlorine, fluorine and hydrogen.
Green house effect: the trapping of the sun's warmth in a planet's lower atmosphere, due to the greater transparency of the atmosphere to visible radiation from the sun than to infrared radiation emitted from the planet's surface.
In large quantities these gasses can change the climate by keeping in too much heat.
Gasses that do this include: water vapour, carbon dioxide, nitrous oxide, methane and CFCs.
CFC: A compound containing carbon, chlorine, fluorine and hydrogen.
4.13 Understand how human activities contribute to greenhouse gases.
Many of the processes that we carry out in homes and factories produce or release gasses with the greenhouse effect.
Greenhouse gasses are produce/released when:
Processes that produce greenhouse gasses include burning fossil fuels and keeping large amounts of live stock.
Greenhouse gasses are produce/released when:
- Things like fossil fuels are burnt
- Chemical reactions take place
- Some plants and animals that we keep a lot of naturally release greenhouse gasses.
Processes that produce greenhouse gasses include burning fossil fuels and keeping large amounts of live stock.
4.14 Understand how an increase in greenhouse gases results in an enhanced greenhouse effect and that this may lead to global warming and its consequences.
- The sun heats up the earth with infra-red waves that it emits.
- The earth emits its own rays so that it maintains its heat instead of just warming up forever.
- Many of these rays escape the earth's atmosphere releasing heat, but some are absorbed by certain Greenhouse gases.
- This means the heat is trapped within the earth's atmosphere.
On a large scale this heats the earth, which we call global warming.
This can lead to climate change:
- The expected weather patterns reversing or exaggerating:
- This is thought to result in natural disasters (drought, floods).
4.16 Understand that eutrophication can result from leached minerals from
fertiliser.
Eutrophication: When there are excessive amounts of nutrients in a lake.
- Farmers use fertilisers to improve quality of their soil (by adding nutrients such as nitrogen).
- When it rains the water dissolves the fertilisers with the water, running it into nearby rivers or lakes.
- This causes an excess amount of nutrients in the water, causing algae to bloom.
- The algae will cover the surface blocking any sunlight and also absorbing most of the oxygen.
- This leads to organisms in the water dying, decreasing the amount of food for fish, so they also die.
4.17 Understand the effects of deforestation, including leaching, soil erosion,
disturbance of the water cycle and of the balance in atmospheric oxygen and
carbon dioxide.
Deforestation has a lot of negative effects on the environment.
Leaching: the loss of nutrients from the soil.
Disturbance of the water cycle: If there are less plants then less water is transpirated into the atmosphere.
Balance in atmospheric oxygen and carbon dioxide: Less plants mean that less carbon dioxide is taken in and less oxygen is released. This as a result means that there will be too high levels of CO₂ in the atmosphere.
Leaching: the loss of nutrients from the soil.
- This is also accompanied by a higher rate of surface run off as there are less plants to protect the soil.
- This is called soil erosion.
Disturbance of the water cycle: If there are less plants then less water is transpirated into the atmosphere.
- This could lead to droughts as there are less clouds.
Balance in atmospheric oxygen and carbon dioxide: Less plants mean that less carbon dioxide is taken in and less oxygen is released. This as a result means that there will be too high levels of CO₂ in the atmosphere.
- Additionally when forests are cut down the trees are usually burnt which releases more CO₂ into the atmosphere.