Water, carbon, climate and life on earth

• Impacts of carbon on the ocean:

  warming oceans - the warmer oceans are, less absorption of carbon dioxide can occur

  ocean acidification - reaction with water making carbonic acid. These molecules can break down and inhibit marine calcification processes. As a result, plankton is weaker, coral is bleached. This is great threat to planetary biological systems.
• Plankton - is a producer at the bottom of the food chain. It is the driving force for marine life.
• Increase in carbon dioxide in the oceans could mean that phytoplankton and ocean plants which take in carbon dioxide directly from the water. Like vegetation on land, these species could become more abundant and have positive impact on the food chain. This is important because phytoplankton is a keystone species, supporting a wide range of life. The amount of phytoplankton also provides negative feedback, with a greater abundance removing carbon dioxide from the water. The water is moved through the biological and eventually geological aspects of the carbon cycle.
• Carbon dioxide absorbed by oceans changes the acidity of ocenas. However, oceans have absorbed 38% of anthropogenically produced carbon. oceans pH levels have only decreased by 0.1 at ocean surface. Despite, this seeming like a low figure, this pH change represents a 30% increase in acidity in the last 200 years.
• Increase carbon dioxide means there is an increase of photosynthesis, increasing phytoplankton resulting in negative feedback.

  Many species are sensitive to temperature and salinity. If this alters at a faster rate than species adapt. This will diminish the number of species.
• Ocean currents

  • oceans exchange water so warm water goes to cold water so that oceans don't freeze. It is driven by salt content, salinity and density of water.
  • the different densities of water are responsible for the waters movement
  • This is the oceans conveyer belt
• As atmospheric temperatures changes, this influences the amount of condensation and evaporation.

  Potential to alter the global atmospheric circulation cells, which in turn would upset surface air movement and ocean currents.
• How H2O and CO2 created the planet:

  1. In earths formative years it was a mass of molten volatility, releasing CO2, ammonia & water vapour forming a basic atmosphere.
  2. Once water was released from volcanoes, it rose and condensed causing tremendous rain storms lasting thousands of years.
  3. Rainfall combined with comet deposits created rivers & oceans. In oceans bacteria was developed. Using energy from the sun and CO2 from the atmosphere, they grew developing O2 as a bi-product.
  4. The O2 allowed new species to develop. CO2 was sequestered into the land & ocean, creating a balance of gases.
• Carbon dioxide causes approximately 20% of the earths greenhouse affect, water accounts for 50% and clouds 25%.

  The level of carbon dioxide plays a very important role in the amount of water and cloud in the atmosphere.
• Carbon is much more stable than water, which can enter and leave the atmosphere easily depending on the temperature.

  Carbon stays in the atmosphere for 20-200 years, so accumulates increasing temperature resulting in influencing water in the atmosphere.
• Increased carbon in the atmosphere leads to increased temperatures,

  which is turn causes more water in the atmosphere via evaporation,

  as a result it could lead increased global warming and increased rainfall leading to the increased likelihood of flooding.
• warm air holds more water = increased rainfall
• Impacts of climate increasing:

  • flooding increases
  • Sea level rise
  • species decline
  • fires increase
  • diseases increases
  • agricultural change
  • permafrost thaws
• Mitigation - the actions (interventions) put into place to reduce or stop climate change by reducing the amount of greenhouse gases in the atmosphere
• Mitigation strategies:

  • alternative energy production
  • carbon capture
  • planting trees (afforestation)
  • international agreement
• What is alternative energy production:

  • renewable or green energy sources, that will never run out

  Examples:

  • solar, wind, tidal, geothermal, HEP, biomass and nucear
• Solar - usesPV cells to convert sunlight into renewable electricity

  Wind-uses power from the wind to turn wind turnbines

  HEP (hydro electric power) - where electricity is made by using the flow of water to turn a turnbine.
• Alternative energy production:

  Advantages:

  • do not produce gases
  • won't run out
  • energy generated without cost
• Alternative energy production

  Disadvantages:

  • expensive to install
  • HEP can cause flooding e.g China one million people had to move and cost $39 billion
  • wind - noisy, ugly and takes upland
• What is carbon capture?

  -capturing carbon dioxide from power plants and safely storing it underground so that it doesn't release into the atmosphere
• Carbon capture

  Advantages - allows us time to develop renewable energy sources whilst keeping our energy output the same

  Disadvantages - distracts governments from renewable energy, money is going into this scheme while wasting money which could be used for sustainable energy and also the carbon could leak out from underground polluting the ground.
• Afforestation- planting trees in order to take carbon out of the atmosphere.

  tress use sunlight to trap carbon dioxide through photosynthesis

  younger tress absorb CO2 quicker while they are growing. If trees are harvested carefully near this time in the growth cycle and new tress are planted then this can keep the forest as a net sink of carbon
• Afforestation

  Advantages:

  • provides habitats
  • reduces co2 in the atmosphere
  • provides shade (urban heat island)

  Disadvantages

  • to reduce co2 we need to plant lots of trees
  • need space for crops to feed the growing population
• International agreement

  COP21 - an agreement by 195 nations on climate change made in Paris in 2015

  the attempt to cut green house emissions to a level that will limit he global average temperature rise
• International agreement

  advantages

  • global difference
  • without agreements some places may continue to pollute causing climate change to get worse

  disadvantages

  • UK and USA had lots of industries. china have produced little CO2 historically by making them reduce their co2 emissions could mean their economy could suffer