N20 hv n2 0 a0337 fim

Robinson and Robbins (1970) think that these processes are effective mainly in the stratosphere. This concept is reasonable since O* concentrations in the stratosphere are greater than in the troposphere. Furthermore, the intensity of U V radiations is also greater above the tropopause. According to Ehhalt et al (1977) the flux of N20 from the troposphere to the stratosphere is between 6 x 108 and 30 x 108 molecules cm 2 s1 which are equivalent to (7-35) x 1061 yr These values are based partly...

Introduction

The concentration of trace substances in the atmosphere is very variable in space and time and their residence time (see Table 1 ) is only some years, weeks or even less. The only exceptions are the noble or rare gases which, with the exception of helium and radon, have no sources and sinks so that we cannot speak of atmospheric cycles in this case. For this reason they are considered permanent constituents and will be omitted from further consideration. The problems related to the water cycle...

Sulfur compounds

Sulfur compounds are very important atmospheric constituents, since in clean tropospheric air as well as in the stratosphere the majority of aerosol particles are composed of ammonium sulfate or sulfuric acid (see Chapter 4). This finding is particularly interesting since with the exception of sea salt sulfur, a predominant portion of sulfur emission is in gaseous form. The study of the atmospheric sulfur cycle is a rapidly expanding field because human activity provides an important sulfur...

[62

Where Q is the incoming solar radiation intensity, while af is the aldebo. By combining 6.1 and 6.2 an equation can be obtained relating the temperature to the intensity of incoming radiation, extent of cloud cover and aldebo. A simple calculation shows that a change of 1 in average albedo produces an average temperature variation of 2.3 C. Schematic diagram showing the effect of aerosol particles on incoming solar radiation (Q,N) according to Schneider and Kellogg (1973). (By courtesy of...

References

G., Fokeieva, E. F. and Ugranov, L. N 1978 Determination of the total nitrous oxide content in the atmosphere (in Russian). Fizika Alm. i Okeana 14, 939-944. Adel, A., 1938 Further detail in the rock-salt prismatic solar spectrum. Asirophys. J. 88, 186-188. Aldaz, L 1969 Flux measurements of atmospheric ozone over land and water. J. Geophys. Res. 74, 6943 6946. Atkins, D. H. F. and Garland. J. A., 1974 The measurement of deposition velocities for sulphur dioxide...

F [cm s

Dry deposition velocity (A) and sedimentation velocity (B) of aerosol particles. Curve A refers to flow over grass (Hidy, 1973). (By courtesy of Plenum Press) Dry deposition velocity (A) and sedimentation velocity (B) of aerosol particles. Curve A refers to flow over grass (Hidy, 1973). (By courtesy of Plenum Press) The deposition velocity defined in 5.3 makes possible the calculation of the dry residence time of particles (Junge, 1963)

Nitrogen compounds 351 Introduction

Several nitrogen oxides are known, including N20 (nitrous oxide), NO (nitric oxide), N02 (nitrogen oxide), N03 (nitrogen trioxide), N203 (dinitrogen trioxide), N204 (dinitrogen tetroxide) and N2Os (dinitrogen pentoxide). At normal temperatures and small partial pressures N203 and N204 decompose according to the following equations (Junge, 1963) For example, owing to this last decomposition, the N204 concentration is 106 ig m if the nitrogen dioxide level is 20 tg m3. Furthermore under normal...

Statement of the problem

It can clearly be seen from Table 1 that the Earth's atmosphere consists mainly of nitrogen and oxygen. However, this composition, which makes the present life on our planet possible, cannot be considered normal in the solar system. Thus, even the nearest planets like Mars and Venus have a very different atmospheric composition. The results of space research, especially the results obtained by the Soviet Venera and the American Mariner space-crafts, make it possible to estimate numerically...

Relation between atmospheric nitrogen and the biosphere

Rasool and De Bergh (1970) mention that nitrogen was accumulated in the atmosphere because of volcanic activity. On the other hand Lovelock (1972) and Lovelock and Margulis (1974) speculate that without the biosphere the Earth's atmosphere would be as depleted in nitrogen as the atmosphere of Mars. According to these authors the nitrogen abundance in the Earth's atmosphere is about 1010 times larger than its equilibrium value under our conditions. Lovelock and Margulis (1974) also think that...

Structure of the atmosphere

Atmosphere Structure Precipitation

One can see from Table 1 that in the Earth's atmosphere molecular nitrogen has the greatest relative concentration near the Earth's surface. The effective molecular weight of air is thus rather close to that of this constituent (the two values are 28.973 and 28.022, respectively). However, the composition of the air and consequently its molecular weight are constant only in the lower 80-100 km layer of the atmosphere which is termed the hoinosphere. Above this layer the so-called heterosphere...