Gases that trap heat in the atmosphere are called greenhouse gases. This section provides information on emissions and removals of the main greenhouse gases to and from the atmosphere. For more information on the other climate forcers, such as black carbon, please visit the Climate Change Indicators: Climate Forcing page.
The Earth has a natural greenhouse effect due to trace amounts of water vapour (H2O), carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) in the atmosphere. These gasses let solar radiation reach the Earth’s surface, but they absorb infrared radiation emitted by the Earth and thereby lead to the heating of the surface of the planet. One needs to distinguish between the natural greenhouse effect and the enhanced greenhouse effect. The natural greenhouse effect is caused by the natural amounts of greenhouse gasses and is vital to life. In the absence of the natural greenhouse effect, the surface of the Earth would be approximately 33 °C cooler. The enhanced greenhouse effect refers to the additional radiative forcing resulting from increased concentrations of greenhouse gasses induced by human activities. The main greenhouse gasses whose concentrations are rising are carbon dioxide, methane, nitrous oxide, hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs) and ozone in the lower atmosphere.
The Global Atmosphere Watch (GAW) observes, analyses and publishes greenhouse gas data collected by fifty countries around the globe from the High Arctic to the South Pole. The greenhouse gasses monitored include:
- Carbon Dioxide (CO2) (incl. Δ14C, δ13C and δ18O in CO2, and O2/N2 Ratios)
- Methane (CH4)
- Nitrous Oxide (N2O)
- Halocarbons and SF6
- Molecular Hydrogen (H2)
The data are collected and distributed by the World Data Centre for Greenhouse Gases (WDCGG) at the Japan Meteorological Agency. The GAW Scientific Advisory Group for Greenhouse Gases (SAG-GHG) advises on the programme development. GAW issues the annual Greenhouse Gas Bulletin, which reports on the latest trends and atmospheric burdens of the most influential, long-lived greenhouse gasses, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), as well as a summary of the contributions of the lesser gasses.
Global Greenhouse Gas Monitoring Infrastructure – Developing the Concept
Currently, most GHG monitoring undertaken globally relies heavily on research capabilities and research funding. The intermittent nature of most research funding and the competitive processes used for its allocation makes sustained global monitoring difficult to achieve.
Ahmed Anaal Abdulla Umar is an 11 year old. His hobbies are playing chess, playing football (not soccer), and playing Minecraft and Black. He is from the Maldives.
Cite this article as:
Ahmed Anaal Abdulla Umar, Greenhouse Gasses, theCircle Composition, Volume 4, (2023). Greenhouse Gasses - theCircle Composition