Global warming

Question 1

Can all wavelengths of electromagnetic waves pass through the Earth’s atmosphere?

Answer 1

Most wavelengths can pass through the atmosphere but infrared radiation is absorbed.

Question 2

Carbon Dioxide occurs naturally in the atmosphere as a result of:

Answer 2

• Natural forest fires.
• Volcanic eruptions.
• Decay of dead plants and animal matter.
• Its escape from the oceans.
• Respiration.

Question 3

What causes man-made carbon dioxide?

Answer 3

• Waste incineration.
• Deforestation.
• Cement manufacuring.

Question 4

Why is water vapour the most significent greenhouse gases?

Answer 4

• Almost all of the water vapour occurs naturally.
• A mere 0.001% comes from human activity.
• Half of the greenhouse effect is due to water vapour and a further quarter is due to clouds

Question 5

How is methene produced?

Answer 5

When organic matter decomposes in an environment lacking oxygen.

Question 6

Natural sources of methane

Answer 6

• Wetlands.
• Termites.
• Oceans.

Question 7

Man-made sources of Methane

Answer 7

• Mining.
• Burning of fossil fuels.
• The digestive tract in animals e.g. cattle.
• Rice paddies.
• Waste in landfields.

Question 8

Greenhouse Effect

Answer 8

1. The electromagnetic radiation from the Sun has a relatively short wavelength.
2. This radiation is absorbed and warms the Earth. The earth then re-radiates the energy as infrared radiation with a longer wavelength.
3. This radiation is absorbed by the greenhouse gases which warm the earth.

Question 9

How does smoke and dust affect the temperature of the Earth?

Answer 9

• The smoke from the factories reflects the radiation from the town back to Earth. The temperature rises as a result.
• The ash cloud from a volcanoe reflects radiation from the sun back into space. The temperature falls as a result.

Question 10

It is important that decisions about global warming are made on…

Answer 10

The basis of scientific evidence and not on the basis of unsubstantiated opinions.

Question 11

Why do the vast majority of scientists agree that the evidence support climate change?

Answer 11

The average temperature of the earth has been increased steadily during the past 200 years.

Question 12

What are the disagreements that scientists have about global warming?

Answer 12

• The extent to which human activity has contributed.
• The seriousness of global warming.
• How much the Earth will warm up.
• What wil happen if it warms up.
• What we should do to stop it.