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♤ Global warming potential describes the impact of each gas on global warming.
♤ The two most important characteristics of a GHG in terms of climate impact are how well the gas absorbs energy (preventing it from immediately escaping to space), and how long the gas stays in the atmosphere.
♤ The Global Warming Potential (GWP) for a gas is a measure of the total energy that a gas absorbs over a particular period of time (usually 100 years), compared to carbon dioxide.
♤ Gases with a higher GWP absorb more energy, per pound, than gases with a lower GWP, and thus contribute more to warming Earth.
GWP & Lifetime of Green House Gases:
S. No | GAS | GWP (100-year) | LIFETIME (years) |
1 | Carbon di oxide | 1 | 100 |
2 | Methane | 21 | 12 |
3 | Nitrous oxide | 310 | 120 |
4 | Hydro fluoro carbons (HFCs) | 140-11,700 | 1-270 |
5 | Perfluoro carbons (PFCs) | 6,500-9,200 | 800-50,000 |
6 | Sulfur hexafluoride (SF6) | 23,900 | 3,200 |
Carbon dioxide (CO2) has a GWP of 1 and serves as a baseline for other GWP values.
♤ The larger the GWP, the more warming the gas causes. For example, methane’s 100-year GWP is 21, which means that methane will cause 21 times as much warming as an equivalent mass of carbon dioxide over a 100-year time period.
♤ Methane (CH4) has a GWP more than 20 times higher than CO2 for a 100-year time scale. CH4 emitted today lasts for only 12 years in the atmosphere, on average. However, on a pound-for-pound basis, CH4 absorbs more energy than CO2, making its GWP higher.
♤ Nitrous Oxide (N2O) has a GWP 310 times that of CO2 for a 100-year timescale. N2O emitted today remains in the atmosphere for an average of 120 years.
♤ Chloro fluoro carbons (CFCs), hydro fluoro carbons (HFCs), hydro chloro fluoro carbons (HCFCs), perfluoro carbons (PFCs), and sulfur hexafluoride (SF6) are called high-GWP gases because, for a given amount of mass, they trap substantially more heat than CO2.
Do you know?
Spices and condiments are flavoring agents obtained from plants. Because they have little nutritive value, they are not classified as foods. They contain essential oils, which impart flavor and aroma to food and add greatly to the pleasure of eating. They stimulate the appetite and increase the flow of gastric juices.
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Shola forest, Temperate forest is an evergreen ecosystem found at the high altitude regions. It is distributed in
Nilgris and Palani hills of Tamil Nadu, Kerala and Karnataka. Sholas are found at sites where adjacent slope converges. These are interrupted by grasslands ecosystem with stunted evergreen woods and confined to sheltered valleys, gleeves, hallows and depressions. The main role of shola forest is conservation of water in that region. It needs well drained soils and avoids swampy soils.