The greenhouse effect
Without The gases responsible for global warming - carbon dioxide, methane, nitrous oxide and CFCs (chlorofluorocarbons). in its The layers of gases that surround the Earth. The important gases in the atmosphere are nitrogen, oxygen and carbon dioxide., the Earth would be about 18 掳C colder on average than it is now. That would make it too cold to support life as we know it.
Greenhouse gases present in the atmosphere include:
- Vapour is a cloud of liquid particles. Steam is water vapour.
- A gaseous compound of carbon and oxygen, which is a by-product of respiration, and which is needed by plants for photosynthesis.
- A colourless gas that can do harm to life forms.
These greenhouse gases:
- absorb heat radiated from the Earth
- then release The capacity of a system to do work or the quantity required for mechanical work to take place. Measured in joules (J). For example, a man transfers 100 J of energy when moving a wheelbarrow. in all directions, which keeps the Earth warm
The diagram gives more details about this process. It is called the The retention of heat in the atmosphere caused by the build-up of greenhouse gases..
Question
Name three greenhouse gases.
Carbon dioxide, methane and water vapour.
Comparison of gases - Higher
Different substances in the atmosphere may absorb, transmit or reflect electromagnetic waves in different ways, depending on the wavelengths of the radiation.
| Gas | Short wavelength radiation (eg ultra violet) | Long wavelength radiation (eg infra red) |
| Nitrogen | Transmit | Transmit |
| Oxygen | Transmit | Transmit |
| Carbon dioxide | Transmit | Absorb |
| Methane | Transmit | Absorb |
| Gas | Nitrogen |
|---|---|
| Short wavelength radiation (eg ultra violet) | Transmit |
| Long wavelength radiation (eg infra red) | Transmit |
| Gas | Oxygen |
|---|---|
| Short wavelength radiation (eg ultra violet) | Transmit |
| Long wavelength radiation (eg infra red) | Transmit |
| Gas | Carbon dioxide |
|---|---|
| Short wavelength radiation (eg ultra violet) | Transmit |
| Long wavelength radiation (eg infra red) | Absorb |
| Gas | Methane |
|---|---|
| Short wavelength radiation (eg ultra violet) | Transmit |
| Long wavelength radiation (eg infra red) | Absorb |
The information in the table shows that carbon dioxide and methane are greenhouse gases because they absorb the long wavelength radiation from the Earth.