Climate System


  
collapse Topic : Causes of Climate Change ‎(2)
Cyclical and Natural Changes
Human-Caused Changes
collapse Topic : Climate System ‎(12)
Atmospheric Circulation
Atmospheric Composition
Carbon Cycle
Climate Compared to Weather
Climate Feedbacks
Global Energy Balance
Greenhouse Effect
Ocean and Climate
Orbital Cycles
Regional Climates
Solar Radiation
Water Cycle
collapse Topic : Human Responses to Climate Change ‎(3)
Personal Responsibility
Risk Management
Social Values
collapse Topic : Impacts of Climate Change ‎(13)
Agricultural Changes
Economic Impacts
Ecosystem Changes
Extreme Weather
Freshwater Resources
Great Lakes Impacts
Melting Ice and Permafrost
Ocean Warming and Acidification
Plants and Animals
Public Health
Sea Level Rise
Surface Temperature Warming
Uncertainty
collapse Topic : Measuring and Modeling Climate ‎(2)
Climate Modeling
Gathering and Measuring Climate Data

Climate Feedbacks

The interconnectedness of Earth’s systems means that a significant change in any one component of the climate system can influence the equilibrium of the entire Earth system.

  • Positive feedback loops can amplify these effects and trigger abrupt changes in the climate system. These complex interactions may result in climate change that is more rapid and on a larger scale than projected by current climate models.

  • The abundance of greenhouse gases in the atmosphere is controlled by biogeochemical cycles that continually move these components between their ocean, land, life, and atmosphere reservoirs. The abundance of carbon in the atmosphere is reduced through seafloor accumulation of marine sediments and accumulation of plant biomass and is increased through deforestation and the burning of fossil fuels as well as through other processes.

 

Decreasing snow and ice and deforestation are examples of positive feedback mechanisms affecting climate change.

  • Snow and ice are highly reflective (have a high albedo) and therefore reflect solar energy back into the atmosphere. When warming temperatures cause snow and ice cover to decrease, more solar energy is absorbed, which in turn causes increased warming.

  • Trees and plants store carbon dioxide from the atmosphere in their leaves, wood, and roots. Removing plants and trees takes away this storage capability and when plants are destroyed, that stored carbon is released back into the atmosphere. The open space left after deforestation is also typically darker and less reflective (lower albedo) than the leaves on the trees. Therefore, more solar energy is absorbed and warming increases.