The Carbon Cycle on a Global Scale

Question 1

What is a Carbon Sink?

Answer 1

Any store which takes in more carbon than it emits

Question 2

What is a Carbon Source?

Answer 2

Any store that emits more carbon than it stores.

Question 3

What is the largest carbon store and its size?

Answer 3

Marine Sediments and Sedimentary Rocks in the Lithosphere. It stores 66,000-100,000 million billion metric tons of carbon.

Question 4

Why is Marine Sediments and Sedimentary Rocks considered a long-term carbon store?

Answer 4

The rock cycle and continental drift recycle the rock over thousands of millions of years

Question 5

What is the second-largest carbon store and its size?

Answer 5

Oceans in the hydrosphere. It stores 38,000 billion metric tons of carbon.

Question 6

Why is the ocean carbon store dynamic?

Answer 6

Carbon is used by marine organisms, lost to the lithosphere, or added through rivers and erosion.

Question 7

How much Carbon is stores in fossil fuel deposits, and why are they considered dynamic?

Answer 7

4,000 billion metric tons of carbon remain, and they are dynamic due to human exploitation.

Question 8

How much carbon is stored in Soil Organic Matter, and how long is it stored?

Answer 8

1,500 billion metric tons of carbon, stored for over a hundred years

Question 9

What Human Activities affect Soil Organic Matter as a carbon store?

Answer 9

Deforestation, agriculture, and land use change.

Question 10

How much carbon is stored in the atmosphere?

Answer 10

750 billion metric tons of carbon

Question 11

What has caused CO2 levels in the atmosphere to increase?

Answer 11

Human activity, increasing CO2 levels by around 40% since the industrial revolution.

Question 12

How much carbon is stored in terrestrial plants, and why is it considered dynamic?

Answer 12

560 billion metric tons of carbon. It is vulnerable to climate change and deforestation.

Question 13

What is happening to carbon storage in forests?

Answer 13

It is declining annually in some areas due to climate change and deforestation.

Question 14

How have Carbon stocks in Brazil and Indonesia changed in the last 25 years?

Answer 14

They have decreases by around 5 Gigatons of Carbon

Question 15

How have carbon stocks changed in Russia, USA, and China in the last 25 years?

Answer 15

They have increased by approximately 0.3,2.9, and 2.3 GtC, respectively.

Question 16

What has caused an increase in carbon sequestration in non-tropical forests?

Answer 16

Conversion of agricultural land and plantations to new forests, particularly in Europe and Eastern Asia.

Question 16

What is the future trend for forested areas in industrialised regions and the global south?

Answer 16

Forests in industrialised regions are expected to increase by 2050, while forested areas in the global south will decrease.

Question 17

How has the rate of forest loss changed over time?

Answer 17

It decreased from 9.5 million hectares per year in the 1990’s to 5.5 million hectares per year in 2010-15

Question 18

Which eight countries have the largest forested land?

Answer 18

Russia, Brazil, china, Canada, USA, DRC, Australia and Indonesia

Question 19

Which country has the most carbon stored on land and the most extensive deforested area?

Answer 19

Brazil

Question 20

Which country has the most carbon stored on land and the most extensive deforested area?

Answer 20

Brazil

Question 21

Which country has the largest amount of afforested area?

Answer 21

China

Question 22

What does Net Primary Productivity refer to?

Answer 22

The amount of carbon stored by forests?

Question 23

How does NPP differ between tropical and deciduous forests?

Answer 23

Tropical forests have a positive NPP year-round, while deciduous forests have a negative NPP in winter but a positive NPP across the whole year.