Carbon cycle

Question 1

Primary source of carbon

Answer 1

-stored in the mantle when the Earth
formed
-it escapes from the mantle at constructive
and destructive plate boundaries as well as hot-spot
volcanoes

Question 2

What is the lithosphere

Answer 2

crust and the uppermost mantle
-hard and rigid outer layer of the earth
-carbon is stored in the lithosphere in both inorganic and organic
form

Question 3

Inorganic carbon in the lithosphere

Answer 3

-fossil fuels like coal, oil, and natural gas, oil
shale (kerogens)
-carbonate-based sedimentary deposits like limestone

Question 4

Organic carbon in the lithosphere

Answer 4

-litter, organic matter and humic substances found
in soils

Question 5

What is carbon in the lithosphere stored as

Answer 5

-marine sediments and sedimentary rocks (100 million GtC)
-soil organic matter contains (1,500-1,600 GtC)
-fossil fuel deposits of coal, oil and gas (4,100 GtC)
-peat, in boggy areas (250 GtC)

Question 6

Oceanic stores

Answer 6

-the surface layer (euphotic zone) where photosynthesis occurs (900 GtC)
-the intermediate (twilight zone) and the deep layer (7,100 GtC)
-living organic matter (30 GtC) and dissolved
organic matter (700 GtC)

Question 7

Biosphere stores

Answer 7

-living vegetation (19%)
-plant litter (leaf tissue being 70%)
-humus
-peat

Question 8

Carbon in the atmosphere

Answer 8

0.04%

Question 9

Where is carbon in the atmosphere measured

Answer 9

-atmospheric carbon has been measured at the Mauna
Loa Observatory (MLO) on Hawaii since 1958
-due to remoteness, undisturbed air, and little influence from vegetation and humans

Question 10

What is the Keeling Curve

Answer 10

A graph made over the span of 50 years that shows the increase of carbon dioxide concentrations in the atmosphere