Earth’s life support systems
4.1 How important are water and carbon to life on earth?
• 1.a: Water and carbon support life on earth and move between the land, oceans, and
atmosphere
• 1.b: The carbon and water cycles are systems with inputs, outputs, and stores
• 1.c: The carbon and water cycles have distinctive processes and pathways that
operate within them
Topic Smaller topic Notes
1.a The The goldilocks zone
importance of • The goldilocks zone is the zone the earth’s situated in, the distance the earth is from the sun is
just right to allow water to exist on the planet
water for
• 71% of the earth’s surface is covered by oceans, they play a pivotal role in temperature regulation
humans, flora,
as absorb CO2 lessening the greenhouse layer
and fauna The importance of water to life on earth
• Only 2.5% is fresh water, the other 97.5% is saline water, which can be made fresh via
desalination, however this is an energy and capital-intensive process
• 69% of fresh water’s stored in glaciers and ice caps, we want this to remain frozen as it traps a lot
of decomposed carbon
• When the ice melts, this water enters river systems and is used for drinking, agriculture, etc. The
downside is the water will eventually enter saline oceans and therefore isn’t much use
• Having glaciers increases the albedo effect which cools planet by reflecting solar radiation
Humans Flora Fauna
-water makes up 60% of human -for photosynthesis, respiration, -water used for circulation of
-water used for circulation of and transpiration oxygen and nutrients
oxygen and nutrients -require water to maintain -evaporative cooling used via
-sweating to cool human rigidity and transport mineral panting
nutrients from soil
-evaporation of water from
leaves surface cools plants
1.a The Biological significance
importance of • Carbon is a common chemical element
• Stored as sea floor sediment, in oceans, the atmosphere, and the biosphere
carbon
• Life’s built on carbon atoms such as protein and carbohydrates
Economic significance
• Fossil fuels like coal, oil, and natural gas power global economy
• Oil used in manufacture of products
• Agricultural crops store carbon and these are available for human use as food, paper, etc
1.a The water and An open system is a system that allows interaction between the internal elements and the environment
carbon cycles A closed system is a system isolated from its environment
The water cycle
• At a global scale, water flows in a closed system between the atmosphere, the oceans, land, and
the biosphere
• At the macro scale (large scale), the global water cycle consists of three main stores, the
atmosphere, oceans, and land
• Water moves between stores via processes of precipitation, evapotranspiration, run-off, and
groundwater flow
The carbon cycle
• At a global scale, carbon flows in a closed system between the atmosphere, the oceans, land, and
the biosphere
• The carbon cycle comprises also a series of stores and flows. Long-term storage in sedimentary
rocks hold 99% of all carbon on earth (60,000,000- 100,000,000Gt)
• In contrast, most of the carbon in circulation moves rapidly between the atmosphere, oceans, soil,
and the biosphere
• The main pathways between stores include photosynthesis, respiration, oxidation, and weathering
Therefore, at a global scale the water and carbon cycle are closed systems driven by the sun’s energy, only
energy, not matter cross the boundaries.
At smaller scales, like drainage basins, materials cross system boundaries, therefore the systems are open
systems.
4.1 How important are water and carbon to life on earth?
• 1.a: Water and carbon support life on earth and move between the land, oceans, and
atmosphere
• 1.b: The carbon and water cycles are systems with inputs, outputs, and stores
• 1.c: The carbon and water cycles have distinctive processes and pathways that
operate within them
Topic Smaller topic Notes
1.a The The goldilocks zone
importance of • The goldilocks zone is the zone the earth’s situated in, the distance the earth is from the sun is
just right to allow water to exist on the planet
water for
• 71% of the earth’s surface is covered by oceans, they play a pivotal role in temperature regulation
humans, flora,
as absorb CO2 lessening the greenhouse layer
and fauna The importance of water to life on earth
• Only 2.5% is fresh water, the other 97.5% is saline water, which can be made fresh via
desalination, however this is an energy and capital-intensive process
• 69% of fresh water’s stored in glaciers and ice caps, we want this to remain frozen as it traps a lot
of decomposed carbon
• When the ice melts, this water enters river systems and is used for drinking, agriculture, etc. The
downside is the water will eventually enter saline oceans and therefore isn’t much use
• Having glaciers increases the albedo effect which cools planet by reflecting solar radiation
Humans Flora Fauna
-water makes up 60% of human -for photosynthesis, respiration, -water used for circulation of
-water used for circulation of and transpiration oxygen and nutrients
oxygen and nutrients -require water to maintain -evaporative cooling used via
-sweating to cool human rigidity and transport mineral panting
nutrients from soil
-evaporation of water from
leaves surface cools plants
1.a The Biological significance
importance of • Carbon is a common chemical element
• Stored as sea floor sediment, in oceans, the atmosphere, and the biosphere
carbon
• Life’s built on carbon atoms such as protein and carbohydrates
Economic significance
• Fossil fuels like coal, oil, and natural gas power global economy
• Oil used in manufacture of products
• Agricultural crops store carbon and these are available for human use as food, paper, etc
1.a The water and An open system is a system that allows interaction between the internal elements and the environment
carbon cycles A closed system is a system isolated from its environment
The water cycle
• At a global scale, water flows in a closed system between the atmosphere, the oceans, land, and
the biosphere
• At the macro scale (large scale), the global water cycle consists of three main stores, the
atmosphere, oceans, and land
• Water moves between stores via processes of precipitation, evapotranspiration, run-off, and
groundwater flow
The carbon cycle
• At a global scale, carbon flows in a closed system between the atmosphere, the oceans, land, and
the biosphere
• The carbon cycle comprises also a series of stores and flows. Long-term storage in sedimentary
rocks hold 99% of all carbon on earth (60,000,000- 100,000,000Gt)
• In contrast, most of the carbon in circulation moves rapidly between the atmosphere, oceans, soil,
and the biosphere
• The main pathways between stores include photosynthesis, respiration, oxidation, and weathering
Therefore, at a global scale the water and carbon cycle are closed systems driven by the sun’s energy, only
energy, not matter cross the boundaries.
At smaller scales, like drainage basins, materials cross system boundaries, therefore the systems are open
systems.
