Topic 1a6-The carbon cycle

How great is the suns energy potential

The sun provides the same energy in a day that humans use in a year.

Define net carbon sink

Carbon entering the store is greater than carbon leaving the store

Define net carbon source

Carbon leaving the store is greater than carbon entering the store

5 major stores of carbon

Lithosphere

Hydrosphere

Cryosphere

Biosphere

Atmosphere

How is carbon stored in the lithosphere

In the crust, upper mantle and soil. There is massive uneven distribution in the stores and can be found in coal, oil and natural gas. Mostly inorganic. It is the largest store of carbon at 40,000GtC

How is carbon stored in the hydrosphere

Mostly liquid but can be all states. Acts as a carbon sink. Second largest store but is tiny compared to the lithosphere

How is carbon stored in the cryosphere

Carbon is stored within ice. Mostly solid with some liquid and gas. Found at high latitudes and altitudes. 

Biosphere

Carbon stored in all living and newly dead organisms on Earth. Over half of the carbon in the biosphere is found in forests. Animals are a small store but an important transfer.

Atmosphere

Carbon dioxide in the air. It can be found in all states and is the smallest store of carbon. Regulates Earth’s temperature and the climate can vary significantly depending on it. The atmosphere is studied mainly in Hawaii.

The slow carbon cycle

Different rock layers in different parts of the Earth contain different things which relate it to different epochs. The carbon inside the rock is locked away for potentially billions of years and enters back into the system through subduction and erosion.

Scales of processes

Continental: where a process is happening at a very large geological scale. For example the carbon cycle in rainforests in South America

Sere: Processes happening for a single biome or ecosystem. For example, a single lake.

Individual plant: Processes happening involving a single tree, eg photosynthesis

What is the carbon cycle in terms of systems

It is a set of cascading open systems

What role does photosynthesis play in the carbon cycle

Part of the fast carbon cycle. Acts as a balance and is a process. Turns CO2 gas into solid organic compounds. Helps lock away carbon for hundreds/thousands of year and regulates global temperature. Happens at an individual plant scale.

What is respiration

Animals, algae and bacteria using stored carbohydrates as energy to carry out functions

What role does respiration play in the carbon cycle

It’s a process from biosphere to atmosphere. Organic to inorganic carbon. Helps naturally regulate amount of atmospheric carbon so regulates global temperature. Mostly maintains dynamic equilibrium with photosynthesis

What role does decomposition play in the carbon cycle

It is the breaking down of dead organisms and is a process that transfers carbon from the biosphere to the lithosphere. Organic to inorganic. Maintains dynamic equilibrium.

What role does combustion play in the carbon cycle

Takes place on the sere scale and is a process. Biosphere+lithosphere to the atmosphere. Rapidly returns carbon to the atmosphere that was previously locked away over geological time scales. Major factor in controlling/affecting climate.

What is and what role does compaction have in the carbon cycle

A process of layering up of organic material. Continental scale seen as white cliffs of Dover. Biosphere+hydrosphere to lithosphere. Organic to inorganic. Locks away carbon over geological time scales.

What is carbon sequestration

A human process of capturing CO2 from the atmosphere and putting it into long term storage. It is an attempt to restore balanced equilibrium to limit climate change.

What is weathering

The physical, biological and chemical processes that cause exposed rock to break down. Continental scale

What are the 3 types of weathering examples

Physical: Freeze thaw-repeated expanding and contracting breaks rocks apart

Biological: Actions of plants and animals. Some physically break rocks apart such as tree roots and burrowing animals

Chemical: Oxidation and acid rain-carbonate rocks such as chalk and limestone get dissolved by rainwater and taken away in solution