The third worst greenhouse gas is methane. Methane comes from both natural and man-made sources. It is released by swamps and termites. Humans release methane trapped underground as a fuel, plus cattle ranching contributes to atmospheric methane. Methane contributes to ozone depletion, plus acts as a greenhouse gas.
It lasts about ten years in the atmosphere before being converted mainly to carbon dioxide and water. The global warming potential of methane is rated at 72 over a 20 year time frame. It does not last as long as carbon dioxide, but has a greater impact while its active. Nitrous oxide comes in at No. This gas is used as an aerosol spray propellant, anesthetic and recreational drug, oxidizer for rocket fuel, and to improve engine power of automotive vehicles.
It is times more effective at trapping heat than carbon dioxide over a year period. The fifth most powerful greenhouse gas is ozone, but it isn't evenly distributed around the globe, so its effects depend on location. Ozone depletion from CFCs and fluorocarbons in the upper atmosphere allows solar radiation to leak through to the surface, with effects ranging from ice cap melting to an increased risk of skin cancer.
An overabundance of ozone in the lower atmosphere, primarily from man-made sources, contributes to heating the Earth's surface.
Ozone or O 3 also is produced naturally, from lightning strikes in air. Fluoroform or trifluoromethane is the most abundant hydrofluorocarbon in the atmosphere. The gas is used as a fire suppressant and etchant in silicon chip manufacture. Fluoroform is 11, times more potent than carbon dioxide as a greenhouse gas and lasts for years in the atmosphere. Hexalfuoroethane is used in semiconductor manufacturing. Its heat-holding capacity is 9, times greater than carbon dioxide, plus this molecule persists in the atmosphere over 10, years.
Sulfur hexafluoride is 22, times more potent than carbon dioxide at capturing heat. The gas finds use as an insulator in the electronics industry. Its high density makes it useful for modeling dispersal of chemical agents in the atmosphere. It's also popular for conducting science demonstrations.
If you don't mind contributing to the greenhouse effect, you can get a sample of this gas to make a boat appear to sail on air or to breathe to make your voice sound deeper. Trichlorofluoromethane packs a double punch as a greenhouse gas. In addition, natural processes in soil and chemical reactions in the atmosphere help remove CH 4 from the atmosphere. Methane's lifetime in the atmosphere is much shorter than carbon dioxide CO 2 , but CH 4 is more efficient at trapping radiation than CO 2.
Pound for pound, the comparative impact of CH 4 is 25 times greater than CO 2 over a year period. Globally, percent of total CH 4 emissions come from human activities. Methane is also emitted from a number of natural sources. Natural wetlands are the largest source, emitting CH 4 from bacteria that decompose organic materials in the absence of oxygen. Smaller sources include termites, oceans, sediments, volcanoes, and wildfires.
To find out more about the role of CH 4 in warming the atmosphere and its sources, visit the Climate Change Indicators page. Methane emissions in the United States decreased by 15 percent between and During this time period, emissions increased from sources associated with agricultural activities, while emissions decreased from sources associated with landfills, coal mining, and from natural gas and petroleum systems.
There are a number of ways to reduce CH 4 emissions. Some examples are discussed below. EPA has a series of voluntary programs for reducing CH 4 emissions, in addition to regulatory initiatives. EPA also supports the Global Methane Initiative , an international partnership encouraging global methane reduction strategies.
Upgrading the equipment used to produce, store, and transport oil and natural gas can reduce many of the leaks that contribute to CH 4 emissions.
Methane from coal mines can also be captured and used for energy. Methane from manure management practices can be reduced and captured by altering manure management strategies. Additionally, modifications to animal feeding practices may reduce emissions from enteric fermentation. Because CH 4 emissions from landfill gas are a major source of CH 4 emissions in the United States, emission controls that capture landfill CH 4 are an effective reduction strategy.
Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K. Averyt, M. Tignor and H. Miller eds. Cambridge University Press. Cambridge, United Kingdom pp. In , nitrous oxide N 2 O accounted for about 7 percent of all U.
Human activities such as agriculture, fuel combustion, wastewater management, and industrial processes are increasing the amount of N 2 O in the atmosphere. Nitrous oxide is also naturally present in the atmosphere as part of the Earth's nitrogen cycle, and has a variety of natural sources. Nitrous oxide molecules stay in the atmosphere for an average of years before being removed by a sink or destroyed through chemical reactions.
The impact of 1 pound of N 2 O on warming the atmosphere is almost times that of 1 pound of carbon dioxide.
Nitrous oxide emissions occur naturally through many sources associated with the nitrogen cycle, which is the natural circulation of nitrogen among the atmosphere, plants, animals, and microorganisms that live in soil and water. Nitrogen takes on a variety of chemical forms throughout the nitrogen cycle, including N 2 O. Natural emissions of N 2 O are mainly from bacteria breaking down nitrogen in soils and the oceans. Nitrous oxide is removed from the atmosphere when it is absorbed by certain types of bacteria or destroyed by ultraviolet radiation or chemical reactions.
To find out more about the sources of N 2 O and its role in warming the atmosphere, visit the Climate Change Indicators page. Nitrous oxide emissions in the United States have remained relatively flat between and Nitrous oxide emissions from mobile combustion decreased by 60 percent from to as a result of emission control standards for on-road vehicles.
Nitrous oxide emissions from agricultural soils have varied during this period and were about 9 percent higher in than in , primarily driven by increasing use of nitrogen fertilizers.
The application of nitrogen fertilizers accounts for the majority of N 2 O emissions in the United States. Emissions can be reduced by reducing nitrogen-based fertilizer applications and applying these fertilizers more efficiently, 3 as well as modifying a farm's manure management practices. Additionally, the introduction of pollution control technologies e. Production of adipic acid results in N 2 O emissions that can be reduced through technological upgrades. No one will like that.
These greenhouse gases mainly include carbon dioxide, methane, nitrous oxide and fluorinated gases. All these greenhouse gases were already part of our atmosphere, but there was a limit for each of them to make the earth a green planet.
Now, this limit has now been crossed due to which we are getting more heat trapped in our environment making it less green and more warm. Hot areas are getting hotter, glaciers are melting more than ever and summers are getting longer throughout the world.
All the government agencies across the world are measuring the use of these greenhouse gases, tracking their use and trying to implement the solutions so that their level in the atmosphere can stay within the limit and stop affecting the normal temperature of this planet. Although the most potent greenhouse gas is Methane, the worst one is still considered to be Carbon dioxide CO2, as it is the primary gas that enters the atmosphere.
This gas occurs naturally in the atmosphere as all animals exhale it during breathing and plants release it at night, also there are volcanic eruptions, wildfires etc. However, human activities in the name of developments, like the burning of petroleum in vehicles and transportation and chemicals in the industries have raised the level of CO2 to a different level, making it a key greenhouse gas that drives global climate change.
This creates a cycle where air pollution contributes to climate change, and climate change creates high temperatures. In turn, higher temperatures intensify some types of air pollution. If the emission of carbon dioxide gas is controlled, it would be an almost complete solution for global warming.
As an individual, you just need to be more cautious with your carbon footprints.
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