Hemispheric inventories

Therefore data on anthropogenic and natural emissions in the Asian region are necessary for the assessment of heavy metal pollution in these countries. Pollution of Kazakhstan and Kyrgyzstan by mercury and lead has been initially assessed by means of hemispheric modeling using the available global emission inventories of the considered heavy metals. The outcomes of the assessment are presented in this section. 

Mechanisms and rates of transport of nuclear test debris in the upper and lower atmosphere are considered. For the lower thermosphere vertical eddy diffusion coefficients of 3-6 X 106 cm.2 sec. 1 are estimated from twilight lithium enhancement observations. Radiochemical evidence for samples from 23 to 37 km. altitude at 31° N indicate pole-ward mean motion in this layer. Large increases in stratospheric debris in the southern hemisphere in 1963 and 1964 are attributed to debris from Soviet tests, transported via the mesosphere and the Antarctic stratosphere. Most of the carbon-14 remains behind in the Arctic stratosphere. 210Bi/ 210Pb ratios indicate aerosol residence times of only a few days at tropospheric levels and only several weeks in the lower stratosphere. Implications for the inventory and distribution of radioactive fallout are discussed. 

Figure 2. Inventories of excess nC in the Northern Hemisphere atmosphere...

The rupture of an 8 inch (20 cm) LPG pipeline resulted in the worst petrochemical incident in the Western Hemisphere (in terms of casualties). This tragic incident occurred in November 1984 within a LPG terminal. The facility received hydrocarbons from three refineries in a suburb of Mexico City. The LPG was stored in six spheres up to 630,000 gallons (2.4 million liters) each and 48 bullet tanks. A total inventory of about 3.8 million gallons (14,400 cubic meters) was on-site at the time of the explosion and fire. Mahoney reported property damages of 19.9 million. (U.S. 1984). [21]... 

Kletz, Trevor A., Plant Design for Safety—A User-Friendly Approach, Hemisphere, New York, 1990. Kletz s easy-to-read, short book argues that additional safety can be achieved with safer substitute materials, lower inventories, lower temperatures, and lower pressures. 

Currently, anthropogenic S02 production exceeds natural SO2 production by a factor of 3 (Bates et al. 1992), but the impact of the former on aerosol production is largely confined to industrialised areas of the Northern Hemisphere. The oceans, on the other hand, cover approximately 70% of the Earth s surface and much of this area is remote from man-made atmospheric contaminants. Consequently, the exchange of marine DMS is of high regional importance and may affect climate globally. Since the publication of a global inventory of DMS data by... 

Actinides in the environment can be classified into two groups (i) the uranium and thorium series of radionuclides in the natural environment and (ii) neptunium, plutonium, americium and curium which are formed in a nuclear reactor during the neutron bombardment of uranium through a series of neutron capture and radioactive decay reactions. Transuranics thus produced have been spread widely in the atmosphere, geosphere and aquatic environment on the earth, as a result of nuclear bomb tests in the atmosphere, and accidental release from nuclear facilities (Sakanoue, 1987). Most of these radionuclide inventories have deposited in the northern hemisphere following the tests conducted by the United States and the Soviet Union. 

This natural inventory was dwarfed by the production of tritium by the atmospheric testing of nuclear fusion weapons during the 1950s and early 1960s. During this period, several hundred kilograms of tritium were released, largely late in the test series, and primarily in the Northern Hemisphere. The... 

The first nuclear test took place in the United States in July 1945. Since then a number of other nations have tested nuclear devices both above and underground. The total amount of fission which took place in the atmosphere is estimated to be a little more than 200 megatons (MT). Most of the explosions occurred in the Northern Hemisphere, and most of the material produced was injected initially into the stratosphere. Careful and continuous monitoring and inventorying of the atmosphere since 1958 has indicated half-residence times for the fallout particulates of about one year in the stratosphere and about one month in the troposphere. Measurements in the stratosphere and upper troposphere showed that the fission product radioactivity was in or on particles with a diameter of. 03 jum or less. ... 

For a few decades, Kr-85 artificial production shows a continuous increase of its average volumic activity into the atmosphere. In the North hemisphere, the atmospheric concentration was of 0.1 Bq m" in 1959, 0.8 Bq m" in 1980, and 1.2 Bq m in 2001 (Berard et al., 2001). One cannot say that the removal of tritium and krypton from gaseous waste is an immediate waste management requirement, but it may become one in the future (Lennemann et al., 1975). Opinions differ as to the need to isolate Kr-85. Thus, Geary (1988) states that dispersal is almost certainly preferable to disposal, based on the relatively low inventories and hazards involved. Mellinger (1985) suggested that the population risks arising from the routine release of Kr-85 would not exceed the occupational risk associated... 

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