Monitoring changes in the carbon cycle

Question 1

Diurnal changes in the carbon cycle

Answer 1

Daytime CO2 flows from the atmosphere to vegetation, this is then reversed at night

Question 2

Seasonal changes in the carbon cycle

Answer 2

Monthly changes in the NPP
Northern hemisphere in summer, trees are in full foliage, net movement of CO2 to the biosphere
Phytoplankton are stimulated into photosynthetic activity by rising water temperatures and more intense sunlight

Question 3

Long term changes in CO2

Answer 3

CO2 levels drop in glacial periods
During interglacial activities CO2 is higher
The carbon pool in vegetation sinks during glacial periods
Tundra replaces forests
Tundra sequesters carbon in permafrost