Chapter 13 Flashcards
Name two ways out present atmosphere is different from our early atmosphere?
We now have 21% oxygen
We have less than 1% carbon dioxide
We have no ammonia
What is the percentage of gas in our present atmosphere?
1% other e.g. Argon (Ar), carbon dioxide (CO2), water vapour (H2O), methane (CH4)
78% nitrogen (N2)
21% oxygen (O2)
Give three factors that have caused our atmosphere to change over millions of years?
- early gases released by volcanoes
- as the earth cooled the water vapour condensed and formed oceans
- carbon dioxide dissolved in the oceans
- plants evolved
- photosynthesis took in carbon dioxide and released oxygen
- decay and the breakdown of ammonia (NH3) increased the levels of nitrogen
What is the greenhouse effect?
Some gases in the Earth’s atmosphere stop heat radiating into space from the Earth. This is called the greenhouse effect and the gases involved are called greenhouse gases. They include:
- methane
- water vapour
- carbon dioxide.
What is global warming?
A gradual increase in the overall temperature of the earth’s atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants
What evidence is there for global warming?
- rising sea level temperatures
- melting of ice caps
- changes to weather patterns
- flooding and drought
- analysis of gases in ice cores
Arguments against:
These are just natural variations that would happen throughout the Earths long history
How has our atmosphere been changing over the last few hundred years?
Increased combustion of fossil fuels since the industrial revolution e.g. increased demand for for electricity, more cars on the road
What does the term carbon footprint mean?
The amount of carbon dioxide released into the atmosphere as a result of the activities of a particular individual, organization, or community
How can we reduce our carbon footprint?
- reduce the amount of electricity we use
- reduce the amount of transport e.g. goods, people
- look at alternative farming methods
- decrease the rate of deforestation
Sulfur dioxide causes…….
Acid rain
What is global dimming?
The reflection of sunlight by tiny solid particles in the air back into space.
Carbon dioxide is a ……………………….
Greenhouse gas, it contributes to global warming
Carbon monoxide is….
Toxic - leads to death by blocking the sites on red blood cells that would be carrying oxygen
Particulates cause ……
Lung damage, global dimming
What is complete combustion?
When a fuel burns in sufficient oxygen
