Greenhouse gases sources

Fig. 121.3 Climate model simulations of global temperature anomalies with (a) and without (b) anthropogenic increases in greenhouse gases. (Source IPCC 2007 AR4 WG 1 Fig. 9.5)...

Canada, 2008b, National Inventory Report 1990-2006 Greenhouse Gas Sources and Sinks in Canada, The Canadian Government s Submission to the UN Framework Convention on Climate Change, Environment Canada, Ottawa [available at www.ec.gc.ca/pdb/ghg/inventory report/2006 report/2006 report e.pdf]. 

Transportation fuels are the largest consumers of crude oil. Petroleum-based transportation fuels are responsible for 35 percent of greenhouse gas emissions m the United States. Only percent of transportation fuels comes from renewable nonpetro-leum-based sources, primarily from the use of corn-based ethanol blended with gasoline to make gasohol. Increased use of biofuels could lower some of the pollution caused by the use of transportatiou fuels. 

If hydrogen is made from decarbonized fossil fuels, fuel-cycle emissions can be cut by up to 80 percent. With renewable energy sources such as biomass, solar, or wind, the fuel cycle greenhouse gas emissions are virtually eliminated. It is possible to envision a future energy system based on hydrogen and fuel cells with little or no emissions of pollutants or greenhouse gases in fuel production, distribution, or use. 

Natural gas will continue to be substituted for oil and coal as primary energy source in order to reduce emissions of noxious combustion products particulates (soot), unburned hydrocarbons, dioxins, sulfur and nitrogen oxides (sources of acid rain and snow), and toxic carbon monoxide, as well as carbon dioxide, which is believed to be the chief greenhouse gas responsible for global warming. Policy implemented to curtail carbon emissions based on the perceived threat could dramatically accelerate the switch to natural gas. 

Concerns over atmospheric methane as a greenhouse gas and the large contribution of biomethanogenesis as a source of this gas make it important to determine the relative significance of various components of this activity. A recent paper (8) summarized estimates (28-30) of source fluxes of atmospheric methane based on several carbon isotopic studies and presented new data on natural sources and biomass burning. These data (Table III) show that of a total flux of 594 million tons (Tg) per year, 83% is produced via biomethanogenesis from a combination of natural (42%) and anthropogenic (41%) sources. 

Methane (CH4), the Earth s third most important greenhouse gas (behind water vapor and CO2) is produced almost exclusively by terrestrial sources (see Chapters 7 and 11). Natural methane sources include anaerobic microbial... 

Nitrous oxide has received increasing attention the last decade, due to the growing awareness of its impact on the environment, as it has been identified as an ozone depletion agent and as a Greenhouse gas [1]. Identified major sources include adipic acid production, nitric acid and fertilizer plants, fossil fuel and biomass combustion and de-NOx treatment techniques, like three-way catalysis and selective catalytic reduction [2,3]. 

The increased energy demand, depletion of petroleum reserves, as well as major concerns of rising greenhouse gas emissions make the implementation of alternative and renewable sources of energy a cracial issue worldwide. 

Anaerobic. Moisture is added to the waste mass in the form of recirculated leachate and from other sources to obtain optimal moisture levels. Biodegradation occurs in the absence of oxygen (anaerobically) and produces landfill gas. Landfill gas, primarily methane, can be captured to minimize greenhouse gas emissions and for energy projects. 

Bayer P., Saner D., Bolay S., Rybach L., Blum P. (2012). Greenhouse gas emission savings of ground source heat pump systems in Europe a review. Renewable and Sustainable Energy Reviews, 16(2), 1256-1267. 

Energy production and consumption pose nature into pressure and make the energy sector becomes the largest contributor of greenhouse gas (GHG) emission in Vietnam since 2010, accounting for 67%. Several emission sources of GHG could be found in a waste treatment facilities it came from (1) emission of methane (CH4, GWP 25) at landfill of mixed waste, (2) from emission of fossil carbon dioxide through the combustion of plastics and composites or supported fuels (auxiliary), and (3) from emission of nitrous oxide (NOx) during incineration/ pretreatment process, etc. 

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