Physical Changes In The Carbon Cycle Over Time

Question 1

What is the Milankovitch cycle?

Answer 1

Natural change in the shape (circular to elliptical) of the Earth’s orbit which influences the amount of sunlight reaching the earth which then affects the temperature.

Question 2

What happens during colder periods?

Answer 2

Restricted plant growth, so then less carbon dioxide absorption.
Colder oceans absorb more carbon dioxide from the atmosphere.
Restricted marine biology growth, so reduced carbon dioxide absorption.
Increased sea ice cover which inhibits the release of carbon dioxide brought to the surface by physical mixing, also stops growth of algae which consumes carbon dioxide.

Question 3

What happens during warmer periods?

Answer 3

Melting of permafrost means the release of carbon dioxide and methane.
More plant growth.
More photosynthesis.
Drier, so slow plant growth, and slowed uptake of carbon dioxide.

Question 4

How much of Earth’s land surface is burned every year?

Answer 4

3 to 4 km2

Question 5

What percentage of carbon stored in forests is emitted during a fire?

Answer 5

10 to 20%

Question 6

What percentage of carbon dioxide emission in the US are equivalent to anthropogenic emissions?

Answer 6

4 to 6%

Question 7

Between 1997-8 what was the growth rate of carbon dioxide in the atmosphere?

Answer 7

It doubled due to deep peat bogs (rich carbon stores) setting on fire within Indonesia.

Question 8

Why is the fire and carbon equilibrium getting out of balance?

Answer 8

Fire suppression, climate warming, increase in fuels and more frequent and severe fires.