Reducing Human Impacts on the Carbon Cycle (DP IB Environmental Systems & Societies (ESS)): Revision Note

Reducing human impacts on the carbon cycle

• Human activities have significantly altered the carbon cycle

  • This has led to increased atmospheric carbon dioxide levels and climate change

• Measures are urgently needed to reduce these impacts and restore balance to the carbon cycle

  • Example of these measure include:

1. Low-carbon technologies:

   • Adopting low-carbon technologies is important for reducing carbon emissions from energy production, transportation, industry and buildings (heating, cooling etc.)

     • Examples include renewable energy sources like solar, wind and hydropower, as well as more energy-efficient technologies and practices (e.g. better insulation and heatpumps)

2. Reduction in fossil-fuel burning:

   • Decreasing the burning of fossil fuels is an essential step in reducing carbon emissions

     • Transitioning to cleaner energy sources, such as renewables can help achieve this

3. Using biomass as a fuel source:

   • Promoting sustainable cultivation of bioenergy crops that does not cause deforestation—bioenergy crops absorb carbon dioxide from the atmosphere as they photosynthesise

   • Utilising bioenergy with carbon capture and storage (BECCS) technology

     • This involves producing energy from biomass

     • The carbon dioxide emissions from biomass combustion are also captured and stored underground

     • Together these processes effectively remove carbon dioxide from the atmosphere

4. Reduction in soil disruption:

   • Decreasing soil disruption through sustainable agricultural practices is vital for preserving soil health and maintaining the ability of soils to sequester carbon

     • Practices such as crop rotation and cover cropping can minimise soil disturbance, erosion and loss of organic matter

     • Healthy soils with high organic carbon content act as carbon sinks, storing carbon and mitigating greenhouse gas emissions

5. Reduction in deforestation:

   • Implementing programs like the UN Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (UNREDD)

     • This prevents deforestation and promotes sustainable forest management

6. Carbon capture through reforestation:

   • Reforestation involves planting trees on deforested or degraded lands to sequester carbon from the atmosphere

     • Trees absorb CO₂ during photosynthesis, storing carbon in their biomass and surrounding soils

     • Forests act as important carbon sinks

7. Artificial sequestration:

   • Artificial sequestration technologies capture CO₂ emissions from industrial processes and power plants, preventing them from entering the atmosphere

     • Methods include carbon capture and storage (CCS), where CO₂ is captured, transported and injected underground for long-term storage

8. Enhancing carbon dioxide absorption by the oceans:

   • Ocean fertilisation techniques involve adding compounds like nitrogen, phosphorus and iron to stimulate the growth of phytoplankton

     • These phytoplankton then absorb carbon dioxide through photosynthesis

   • Using methods to increase ocean upwellings

     • These upwellings bring nutrient-rich deep waters to the surface

     • This has the same effect of promoting the growth of phytoplankton and enhancing carbon dioxide absorption