Water and Carbon

  1. How important are water and carbon to life on Earth?

How is Water important for life?

Climate:

Water is critical to life on a planet because it provides a medium. that allows organic molecules to mix and form more complex Structures. Water helps to Create benign thermal conditions on earth, such as the oceans which occupy 71% of the earth's Surface. Additionally, water moderates temperature by absorbing heat, Storing it and slowly releasing it. tiny water droplets and ice Clouds are made up of crystalls which reflect incoming solar radiation and so lowers a ffth of Surface temperature. At the same time, water vapour absorbs long-wave radiation helping to maintain global temperatures 15°c higher than they would.

Plants:

- Water makes up 65-95% of all living organisms and is crucial to their growth, reproduction and other metabolic functions. Plants use water to photosynthesis: water + Carbon Dioxide → glucose oxygen. Plants also require water to maintain their rigidity and fransport mineral nutrients from the soil. Furthermore, transpiration of water from leaf Surfaces cools plants by evaporation.

People & Animals:

- In People and animals, water is the medium used for all Chemical reactions in the body including the circulation of oxygen and nutrients. The body sweats Isimular way to transpiration in plants) to cool the body down. Additionally, in fur-covered animals, reptiles and birds evaporative cooling is achieved by panting.

Economic:

Water is also an essential resource for economic activity. This is because it is used to generate electricity, irrigate crops, provide recreational facilities and Satisfy public demand (drinting water, Sewage disposal). Furthermore, water is used in industries such as food manufacturing, brewing, Paper + Steel mating.

How is Carbon Important for life?

Economic:

Apart from its biological significance, carbon is used as an economic resource. Fossil fuels such as coal, oil and natural gas power the global economy. Oil is also used as an es raw material in the manufacture of products ranging from plastics to paint and Synthetic fabrics. Agricultural crops and forest trees also Store large amounts of carbon available for human use as food, timber, paper, textiles and many other products. 80% Global Energy is from fossil fuels such as Carbon.

Life:

- Life as we know it is carbon based: built on large molecules • of Carbon atoms such as proteins, carbohydrates and nucleic acids. Our body contains carbon (18%), the air we breathe Contains carbon dioxide and the food and clothes contain Carbon, It's used in Photosynthesis. Important for flora, fauna.

- No Synthetic Carbon available. indicating their unique importance. Ubiquitous from atmosphere, to sea bed sediments to all forms of flora and fauna. Estimated to form 95% of all tknown compounds. A natural greenhouse effect / regulator of climate.

Where is carbon stored:

  • Biosphere: 0.0012%

  • Pedosphere: 0.0031%

  • Hydrosphere: 0.038%

  • Atmosphere: 0.0017%

  • Fossil Fuels: 0.004%

  • Lithosphere: >99.9%

Biosphere:

Trees, plants and all other living organisms (including aquatic)

Through photosynthesis, plants convert the sun's energy and Carbon is the air into carbohydrates which enter the food chain and Support life.

Terrestrial plants and living organisms contain 560 billion tons of carbon. But only 0.0012% of all carbon on Earth

Most biosphere carbon is stored in regions of high primary productivity, like tropical rainforests and temperate forests.

Atmosphere:

750 billion tones of Carbon - 0.0017% of all carbon.

Mostly in the form of Carbon Dioxide (cos) and Methane CH both are greenhouses-gases

Over the last century, Carbon has increased by 36% in the atmosphere. leads to global warming.

Hydrosphere:

• 0.038% or 38,000 billion tonnes of carbon.

• 90% of oceanic Carbon is dissolved in sea water as bicarbonate

Lithosphere

Limestone is made up of the Shells of sea creatures from hundreds of millions of years ago, which are made t of carbon

Over 99.9% of all earths Carbon is stored in marine Sediment and Sedimentary rocks.

Pedoshpere:

Peat is made up of organic matter; dead material from 1st complants and other organisms. 60% Carbon (dark colour)

0.0031% of all Carbon on Earth.

Fossil Fuels:

• Over millions of years, organic matter gets burned deeper ales into the ground, where the pressure and heat is very high This Converts the organic matter to fossil fuels; oil, coal 1, and gas.

4,000 billion tonnes or 0.004% of Earth's Carbon.

Carbon Cycle

Slow Carbon Cycle

Carbon is stored in Sedimentary rocks for millions of years. It is released by Volcanic action, chemical weathering, erosion and recently human activity.

Fast Carbon Cycle

Carbon dioxide is absorbed out of the atmosphere by the oceans and by plants and phytoplankton. It is released back into the atmosphere as the plants respire or are decomposed

LONG TERM/ SLOW CARBON CYCLE:

→100-200 million years for carbon atoms to move through the cycle

1. The atmosphere contains carbon dioxide.

This combines with water vapour to produce carbonic acid.

3. This acidic rainfall reacts with minerals in the rock.

4. This causes chemical weathering.

5. Some of the carbon is released back into the atmosphere

6. Some enters the hydrosphere

7. Molecules produced by the reaction are washed downstreams" bid and rivers into the ocean, alamhoud mon

8. The oceans also absorb carbon directly from the atmosphere.

9. The carbon in the ocean goes into Shells and Skeleton of marine Creatures as calcium Carbonate.

10. When these organisms die, they will sink to sea floor and build up in layers. Over millions of years, they compact down to create sedimentary rocke

12. Under heat and pressure, carbon from organic matter trapped in the Sediment is converted into fossil fuels - Sequestration.

13. Sea floor moves towards destructive plate boundaries, where it is Subducted down into the Earth's Mantle

14. Under extreme heat and pressure, carbon contained in rocks is released and rushes back to the surface.

15. Returns to the atmosphere through a volcanic eruption. 4200 million tonnes of Co2

Sequestration - process by which carbon is removed from the atmosphere and stored in Liquid or solid form.

SHORT TERM/ FAST CARBON CYCLE:

Unique to Earth as it's the flow of Carbon through the biosphere.

1. Plants are primary producer organisms, they absorb Carbon dioxide from the atmosphere + energy (sun) Carbohydrates + oxygen..

2. Phytoplankton do photosynthesis too in the ocean.

3. Life is fueled by the breakdown of Carbohydrates release co2 back.

4. Plants and animals that eat them break down carbohydrates to release energy required.

5. As they do this, Co₂ is released through respiration and methane (digestion system)

6. As plants and animals die and decompose bacteria and fungi break down carbohydrates releasing CO2 and CH4 back to atmosphere - Decomposition

7. Some carbon is transferred into the soil in form of humus

8. Fire / Combustion releases carbon back to atmosphere.

Through the processes of photosynthesis, respiration, decomposition. D and combustion, between 1,000,000,000 to 100,000,000, tonnes of carbon moves through carbon cycle every year.

Processes of the carbon cycle:

Carbon exchanges:

Atmospheric CO2 dissolves in rainwater to form carbonic acid. increase in CO2 concentration due to anthropogenic emissions increased acidity of rainfall. This increased acidity of ocean surface water, harming marine life.