Emission anthropogenic

Stratospheric distribution of NjO Atmospheric accumulation of NjO (0.25% yr ) Natural emissions (largely from tropical soils) Anthropogenic emissions cultivated soils (-h industry and combustion) 40 8.0 (. 1 sources... 

Forests can act as sources of some of the trace gases in the atmosphere, such as hydrocarbons, hydrogen sulfide, NO, and NH3. Forests have been identified as emitters of terpene hydrocarbons. In 1960, Went (10) estimated that hydrocarbon releases to the atmosphere were on the order of 108 tons per year. Later work by Rasmussen (11) suggested that the release of terpenes from forest systems is 2 x 10 tons of reactive materials per year on a global basis. This is several times the anthropogenic input. Yet, it is important to remember that forest emissions are much more widely dispersed and less concentrated than anthropogenic emissions. Table 8-2 shows terpene emissions from different types of forest systems in the United States. 

Anthropogenic Emissions and Climate Variability. Journal of Geophysical Research 103(DI 3) 15979-15993. Fkickinger, J., ct al. (1999). Variations in Atmospheric NjO Concentration During Abrupt Climate Changes. Science 285 227-230. 

Clean and Polluted Air. In the development of atmospheric chemistry, there has been an historic separation between those studying processes in the natural or unpolluted atmosphere, and those more concerned with air pollution chemistry. As the field has matured, these distinctions have begun to disappear, and with this disappearance has come the realization that few regions of the troposphere are completely unaffected by anthropogenic emissions. An operational definition of clean air could be based upon either the NMHC concentration, or upon the NOjj concentration. 

In remote ice cores, SO and NOJ concentrations have increased due to anthropogenic emissions (Mayewski et ai, 1986, 1990). This is due to the fact the precursor compounds (e.g.. 

Kato, N. and Akimoto, H. (1992). Anthropogenic emissions of SO2 and NO in Asia Emission inventories, Atmos. Environ. 26A, 2997-3017. 

The ratio of anthropogenic emissions to total natural emissions is highest for the atmophilic elements Sn, Cu, Cd, Zn, As, Se, Mo, Hg, and Pb (Lantzy and Mackenzie, 1979). In the case of lead, atmospheric concentrations are primarily the consequence of the combustion of leaded gasoline. For many years, lead was used as a gasoline additive, in the form of an organometal compound, tetraethyl lead. When the fuel was... 

Indeed, the most important factor that affects the future estimates of climate is the (anthropogenic) emissions of greenhouse gases and all kind of aerosols. The amount of these products released into the atmosphere depends upon the socio-economical and technological development of humankind. Thus, different hypotheses about these evolutions are assumed, resulting in several emission scenarios. The scenarios used in the IPCC AR4 derive from a Special Report on Emission Scenarios (SRES) published earlier [2]. All these scenarios can be grouped in four families (storylines) that are named Al, A2, Bl, and B2. 

FIGURE 1.3 Anthropogenic emissions of total mercury in 1995 (tonnes). (Reprinted with permission from Pacyna et al. 2003.)... 

FIGURE 1.4 Change of global anthropogenic emissions of total mercury to the atmosphere from 1990-2000 (metric tons). (Reprinted from Pacyna et al. 2006, with permission from Elsevier.)... 

Pacyna JM, Pacyna EG, Steenhuisen F, Wilson S. 2003. Mapping 1995 global anthropogenic emissions of mercury. Atmos Environ 37(Suppl. 1) S109-S117. 

Jackson TA. 1997. Long-range atmospheric transport of mercury to ecosystems, and the importance of anthropogenic emissions — a critical review and evaluation of the published evidence. Environ Rev 5 99-120. 

If all parts of the livestock production lifecycle are included, livestock are estimated to account for 18% of global anthropogenic emissions [57]. According to Gill and coworkers [57], apart from enteric fermentation and manure management, the other sources of GHG emission from livestock and related activities are fossil fuels used during feed and fertilizer production and transport of processed animal products. 

The primary source of lead in the environment has historically been anthropogenic emissions to the atmosphere. In 1984, combustion of leaded gasoline was responsible for approximately 90% of all anthropogenic lead emissions. EPA phased out the use of lead alkyls in gasoline, however, and by 1990, auto emissions accounted for only 33% of the annual lead emissions (EPA 1996h). Use of lead additives in motor fuels was totally banned after December 31, 1995 (EPA 1996f). The ban went into effect on February 2, 1996. Atmospheric deposition is the largest source of lead found in soils. Lead is transferred... 

Nriagu J O. Global inventory of natural and anthropogenic emissions of trace metals to the atmosphere. Nature 1979 279 409M11. 

F —mobilization factor as a ratio of anthropogenic emission into the atmosphere to the natural one... 

Figure 1. Spatial distribution of lead anthropogenic emission in Europe in 2002.

Apart from anthropogenic emissions, heavy metals enter the atmosphere of Europe due to re-emission of previously deposited substances and from natural sources. These types of sources are taken into account on the basis of expert estimates made in MSC-E (Ryaboshapko and Ilyin, 2001 Travnikov and Ryaboshapko, 2002). 

In 2002 anthropogenic emissions of lead in Europe amounted to 8 x 103 tons per year (kt/yr). This is about 11% less than in 2001. In addition, natural emissions and re-emissions made up 1 kt/yr. The total depositions to Europe in 2002 were 6.7 kt. 

A significant amount of lead emitted in a country is transported beyond the national borders contributing to the trans-boundary transport. In 2002 as much as 4.8 kt (around 60% of total anthropogenic emission) of atmospheric lead, emitted in Europe were involved in transport across state borders. Absolute magnitudes of lead transported outside countries vary substantially from country to country. It was calculated as difference between national emission and deposition to the country. This magnitude depends on national emission, size of the territory, climatic conditions and spatial distribution of emission sources within the country. 

In 2002 anthropogenic emission of cadmium in Europe amounted to 257 t/yr that is 5% lower than in 2001. Emission caused by natural processes (natural emission and re-emission) add up 55 t/yr. Depositions to Europe in 2002 were 240 t/yr. Spatial distribution of cadmium deposition in Europe is shown in Figure 9. The regions... 

Each country is not only a receptor but also a source of the trans-boundary transport. As much as 153 t (60% of anthropogenic emission in Europe) of cadmium, emitted in Europe, leaves the territory of the counties and is involved in the long-range transport. The highest absolute value—30 t/yr—of cadmium transported across national borders was obtained for Poland. The significant exporters of cadmium are Spain, the Russian Federation, Romania and Italy. Nearly 40 t of cadmium is transported outside the European Union. Besides, only nine countries control more than 75% of cadmium trans-boundary transport. 

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