Our Blue Planet

Question 1

What proportion of the Earth’s surface is covered by oceans?

Answer 1

70%

Question 2

What percentage of the water available on the globe is contained in the ocean?

Answer 2

97%

Question 3

What percentage of the Earth’s biomass is made up of marine microbes?

Answer 3

50%

Question 4

What percentage of the Earth’s surface area is taken up by coral reefs?

Answer 4

0.1%

Question 5

What percentage of global marine systems are covered with seagrasses and mangroves?

Answer 5

0.5%

Question 6

What percentage of the Earth’s surface is sea ice?

Answer 6

7%

Question 7

What proportion of atmospheric CO2 is taken in by the ocean?

Answer 7

One third

Question 8

What percentage of the Earth’s carbon dioxide is cycled and stored through marine systems?

Answer 8

Over 90%

Question 9

What percentage of carbon storage in marine sediments is from seagrasses and mangroves?

Answer 9

50%

Question 10

What is the average temperature range of the ocean surface?

Answer 10

Between -2 °C (polar regions) and 30 °C (tropical regions)

Question 11

What is a eutrophic zone?

Answer 11

A nutrient-rich area in the ocean or a body of water that supports high primary productivity

Question 12

What is an oligotrophic zone?

Answer 12

A nutrient-poor area with low primary productivity, typically found in the open ocean or deep tropical waters

Question 13

What does “glacio-eustatic” mean?

Answer 13

It refers to global sea level changes caused by the growth or melting of large ice sheets and glaciers