Emission from ocean

Corbett, J. I and P. S. Fischbeck (1997) Emissions from ships. Science 278, 823-824 Corbett, I J. and H. W. Koehler (2003) Updated emissions from ocean shipping. Journal of Geophysical Research 108, doi 10.1029/2003JD003751 Cossa, A. (1867) Ueber die Ozonometrie. Zeitschrift fur Analytische Chemie 6, 24-28 Cosovic, B., P. Orlovic Leko and Z. Kozarac (2007) Rainwater dissolved organic carbon characterization of surface active substances by electrochemical method. Electroanalysis 19, 2077-2084... 

Nitrous oxide, N2O 0.3 ppb Rising Uniform Emission from soils, 10 Emissions from oceans, 6 Anthropogenic, 9 Loss to stratosphere, 19 llOyr... 

Carbonyl sulfide, OCS 500 ppt Uniform Soils and marshes, 0.3 Emission from ocean, 0.3 Oxidation of CS2 and DMS, 0.5 Uptake by vegetation, 0.5 Reaction with OH, 0.13 Loss to the stratosphere, 0.1 7yr... 

Carbon disulfide, CS2 <30 ppt 35-190 ppt Marine air Continental air Emission from ocean, 0.4 Anthropogenic, 0.6 Reaction with OH 7d... 

Dimethyl sulfide. 20-150 ppt Marine air Emission from oceans, 50 Reaction with OH 2d... 

Methyl chloride, CH3CI 600 ppt Uniform Emissions from ocean, 3 Biomass burning, 0.7 Reaction with OH 1.3 yr... 

One of the most hazardous heavy metal emitted to the atmosphere due to its toxicity is mercury. It is released to environment naturally and through human activities in three forms such as elemental (Hg ), oxidized (Hg ) and particulate (HgP). The examples of natural emission source are emission from ocean and volcanic eruptions, whereas, fuels used for energy production and raw materials used in industrial processes are anthropogenic source of mercury (Pacyna et al. 2006, Pirrone et al. 2010). The latest data revealed that the global pool of mercury mainly results from anthropogenic emissions... 

Acid rain is caused primarily by sulfur dioxide emissions from burning fossil fuels such as coal, oil, and natural gas. Sulfur is an impurity in these fuels for example, coal typically contains 2-3% by weight sulfur.1M Other sources of sulfur include the industrial smelting of metal sulfide ores to produce the elemental metal and, in some parts of the world, volcanic eruptions. When fossils fuels are burned, sulfur is oxidized to sulfur dioxide (SO2) and trace amounts of sulfur trioxide (SC>3)J21 The release of sulfur dioxide and sulfur trioxide emissions to the atmosphere is the major source of acid rain. These gases combine with oxygen and water vapor to form a fine mist of sulfuric acid that settles on land, on vegetation, and in the ocean. 

The second important source for the hydrosphere and the oceans are asteroids and comets. Estimating the amount of water which was brought to Earth from outer space is not easy. Until 20 years ago, it was believed that the only source of water for the hydrosphere was gas emission from volcanoes. The amount of water involved was, however, unknown (Rubey, 1964). First estimates of the enormous magnitude of the bombardment to which the Earth and the other planets were subjected caused researchers to look more closely at the comets and asteroids. New hypotheses on the possible sources of water in the hydrosphere now exist the astronomer A. H. Delsemme from the University of Toledo, Ohio, considers it likely that the primeval Earth was formed from material in a dust cloud containing anhydrous silicate. If this is correct, all the water in today s oceans must be of exogenic origin (Delsemme, 1992). 

The oceanic burden in December 2004 shows the contamination of the ocean after 50 years of PFOA emissions (Figure 3.14). Highest PFOA burden is located in the northern Atlantic, Mediterranean, and the Arctic ocean. Contaminations of the Atlantic, Mediterranean and Pacific can be related to the vicinity to the oceanic source. PFOA in remote regions, however, such as in the Arctic must have been transported via atmosphere or ocean. MPI-MTCM does not simulate degradation of PFOA from volatile, highly mobile precursor substances, that contribute to the ocean burden in the Arctic by deposition. Then annual dry and wet deposition rates of PFOA in the model are small compared to the mass emitted directly to the ocean. This implies that the burden in the Arctic is results mainly from oceanic long-range transport. 

In the mid Atlantic ocean observed concentrations at A03 and A04 decrease gradually with depth, whereas A05 concentrations show an increase until 500 m and a decrease below. Modeled profiles show a similar pattern. Surface concentrations of model results are much lower than the observed ones. In addition to this the fact that profiles of all mid Atlantic sampling location are identical can be explained by missing discharge into the mid Atlantic ocean in the emissions scenario. Emissions from American fluoropolymer productions sites are released into the Atlantic Ocean solely at the mouth of St. Lawrence River. Discharge of PFOA into for example the Gulf of Mexico is not considered. 

The major pathways of pollutant input to the ocean are listed in Table 28.2. These can be classified into two categories emissions from discrete sources, called... 

Tropospheric chemistry models have to take into account a significant number of chemical reactions required to simulate correctly tropospheric chemistry. In the global background marine troposphere, it seems reasonable to consider a simplified chemistry scheme based on O3/ NOx/ CH, and CO photochemical reactions. However, natural emissions of organic compounds from oceans (mainly alkenes and dimethyl sulphide-DMS) might significantly affect the marine boundary layer chemistry and in particular OH concentrations. Over continental areas both under clean and polluted conditions,... 

The comparably low pollution levels in Berlin - the non-critical area in this comparison - is due to favourable dispersion conditions (flat terrain and moderate oceanic climate), comparably low emissions from industry and domestic heating, low emission densities and effective air quality management. 

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