atmosphere

Question 1

Timeline of change of the atmosphere

Answer 1

• During first Billion years there was intense volcanic activity
• Volcanos realsed gasses that formed early atmosphere
• Gasses where water vapour, carbon dioxide, nitrogen
• small amounts Methane and Ammonium
• Earth atmosphere contained little to no oxegen, so very simular to planets like Mars and Venus.
• Earth cooled down and water vapour developed to form the oceans
• Some of carbon dioxide dissolved into oceans forming a weak acid
• This reacted with minearls in the sea to form preciptates
• Over time this formed sediments of carbonate rock on the seabed
• Some of carbon dioxide made coral and shells of organisms
• When they died they formed the sedementry rock limestone, while removing carbon dioxide from atmosphere
• Level of carbon dioxide began to fall
• Around 2.7 billion years ago the first Photosynthetic algae evolved in the oceans
• Proccess of photosynthisis produced oxegen which entered the atmosphere
• Plants evolved increasing amount of oxegen in atmosphere reaching point where animals could evolve

Question 2

Pecentage of gasses in the modern atomsphere

Answer 2

• 78% Nitrogen
• 21% Oxegen
• 0.04% Carbon dioxide
• 1 perecent everything else

Question 3

Early atmosphere

Answer 3

Lots of
- Carbon di-oxide
- Water vapour
- Nitrogen
Smaller amounts of
- Methane
- Ammonia

Question 4

Why can scientist not be certian about the early compositon of the atomosphere

Answer 4

The earth is around 4600 million years old, that means scientist cannot be sure about the early atmosphere

Question 5

How do greenhouse gasses work

Answer 5

• Suns heat energy goes down onto earth in form of shortwave radiaton
• Passes through atmosphere and hits surface of earth
• Some of the energy is absorbed and heats up ground
• Most is remmited or reflected into the atmosphere towards space in form of Longwave radiaton
• Some energy makes it back to space
• Most hits particles of Gas in atmosphere, which absorbs energy they then reimmit the energy in random dirrections
• Some energy remmited towards spave and some towards earth
• Most energy collides with other gas particles before leaving the atmosphere
• Proccess repeates keeping heating earth longer than if there was no atmosphere
• Keeps earth at stable temp