Life on earth

• The Kyoto Protocol is an international treaty adopted in 1997 that committed industrialised countries to reduce their greenhouse gas emissions.
• With regard to the carbon cycle, an example of a negative feedback loop is that warmer temperatures extends the plant growing season. This increases carbon absorption from the atmosphere and increases the carbon sink in the soil.
• Peatlands are thick organic soils that are low in oxygen and high in water, which inhibit microbial decomposition of plant litter allowing for thick organic layers to build up.
• Water vapour contributes 55% to the natural greenhouse effect, while CO2 contributes 20%.
• Grasslands can sequester approximately 810 million tonnes of CO2 globally.
• Melting permafrost acts as a positive feedback loop because methane is released into the atmosphere. Methane is a more potent greenhouse gas than CO2. Currently, the permafrost stores hundreds of gigatons of methane.
• Carbon capture and storage (CCS) technology can capture up to 90% of CO2 emissions.