Balanced Carbon Cycle Crucial for Earth Systems, Disrupted by Human Activities

Carbon Forcing → 🔗The influences that cause changes to the Earth's climate system altering Earth's radiative equilibrium, forcing temps to rise or fall

Carbon Fertilisation → 🔗The extra growth of plants due to the presence of more atmospheric CO2 and ∴ more Carbon

Ocean Acidification → 🔗The dissolving of CO2 in the ocean causes carbonic acid to form

↳ A balanced carbon cycle is important to sustain other systems

• Plays a key role in regulation of the Earth's global temperature by controlling amount of CO2 in atmosphere

Natural Greenhouse Effect

↳ The earth has a natural temperature-control system that relies on greenhouse gases

• The conc. of atmospheric carbon strongly influences the greenhouse effect Three Major Greenhouse Gases

1. Carbon dioxide
2. Methane
3. Nitrous oxide (nitrogen cycle)

• Heat energy from the sun warms the planet, but without the atmospheric greenhouse gases, this would not be enough to support life
• The heat energy that is reflected back towards space from the earth's surface and lower atmosphere has a relatively long wavelength, so it has difficulty travelling through denser gases and is absorbed by them
• Without this, the avg temp of the Earth would be 21C cooler Distribution of Temperature and Precipitation

↳ Greenhouse gases ↑ temps, which affects precipitation patterns

Ocean and Terrestrial Photosynthesis

↳ Takes place on land and in ocean (wherever plants are present)

• Regulates the composition of the atmosphere by balancing O2 and CO2

Soil Health and Photosynthesis

Photosynthesis

• Regulates the NPP of veg around the world and ∴ plays a role in regulating atmospheric CO2 levels and global temps
• NPP highest in tropical rainforest and warm shallow oceans
• NPP is lowest in the arid and tundra areas

Soil Health

• Amount of carbon in a soil determines its health (productivity)
• Soil health is determined by the net carbon balance between inputs and outputs
• There is a strong positive relationship between soil health and ecosystem productivity

Fossil Fuel Combustion

• People → Influenced the carbon cycle where fossil fuels have been mined and subsequently burnt
  • CO2 is a greenhouse gas that enhances atmospheric heating and contributes to climate change

Relationships Between the Water Cycle, Carbon Cycle and Climate Change

• Changes to the carbon cycle are the causes of climate change, through the combination of the greenhouse effect
• Climate change is having an effect on the water cycle, such as increased EVT and precipitation
• Climate change has an effect on the carbon cycle as more CO2 released from permafrost as ↑ temp causes melting
• Longer plants growing seasons ∴ plants need more water
• Higher temps cause soil baking which causes an ↑ in the rate carbon seeps out of the soil in some places
• Melting of permafrost releases CH4 and CO2 due to the decaying of organic matter & carbon

Further Implications of Climate Change

• More extreme weather events
• Melting of ice caps and glaciers causes rising sea level and flooding coastal cities
• Declining ecosystem biodiversity, ocean acidification and coral bleaching
• CO2 causes ↑ temps ∴ expending the growing season & ↑ in humidity = additional plants growth

Climate Predictions

Global	Regional
● General temps will ↑ ● Sudden shifts in weather patterns ● More extreme weather events ● Rising mean sea level	● Some regions will become warmer and drier and others wetter ● Some regions will have less snow and more rain ● Storm surges may ↑

Implications for Ecosystems

↳ Help to regulate carbon and hydrological cycles

• Marine organisms are threatened w/ progressively lower O2 rates and magnitudes of ocean acidification
• Rising temperature may alter the foundation of the food chain
• Majority of species will be negatively affected by climate change but some will benefit

Implications for the Hydrological Cycle

↳ The hydrological cycle's flows and stores are vulnerable to global warming

• The most likely implication will be increased temperatures and evaporation rates therefore leading to more moisture circulating around the cycle