Launches might influence the weather significantly on for short periods and on a small-scale, but are not expected to have any major large scale weather effects. The air quality is not expected to change noticeably, except for a slight increase in nitrogen dioxide. This increase might also cause a very slight and short lasting increase in the acidity of precipitation. The injection of carbon dioxide in the stratosphere is expected to be too small to cause any modification to the greenhouse effect. The injection of water in the stratosphere is expected to be too small to have any effects on the ozone layer, while the production of nitric oxide during re-entry of the second stage of rockets should cause a slight increase in the ozone density. In the mesosphere, water vapor should increase by a few percents at low altitude and by as much as a factor of 100 or more at high altitudes. This will cause an increase in the upward flux of hydrogen from the mesosphere to the thermosphere, which might then cause either an increase in the density in the thermosphere (by accumulation of hydrogen) or an increase in the escape rate of hydrogen. As noted in the “report of the workshop on the modification of the upper atmosphere by satellite power system (SPS) propulsion effluents”, the general humidity enhancement of the mesosphere might produce long-lasting contrails which might disturb remote sensing from satellites, while the potential hydrogen concentration enhancement in the thermosphere would increase the (frag on low altitude satellites. For various reasons, the plasma densities in the ionosphere might change. Due to the variety of effects involved, the sign of the change in the different layers is hard to assess, except in the F-region, where it is expected to decrease substantially. This decrease would perturb wave propagation and might also increase airglow. On the other hand, the NASA study previously mentioned expects the perturbation of wave propagation to be minimal. Effects on the magnetosphere are not well understood but cause concern since injected amounts of material and energy are large compared to natural occurring values. Possible effects include increased airglow, artificial currents similar to those caused by magnetic storms which would induce currents in power and telephone lines as well as plasma instabilities which would cause communication interferences. No corridor effect (changes in concentration of major constituents in a narrow latitude zone centered on the launch point) are to be expected. Effects on the Ocean Launches are responsible for water pollution because NOX is included in the rocket exhaust. Two main aspects must be considered. • the question of local, intermittent effects associated with individual launches • the question of regional, long-term contributions representing cumulative effects over the entire period of high-rocket-launch activity According to DOE's report of “ Environmental Assessment for the Satellite Power System-Concept Development and Evaluation Program-Atmospheric Effects “ published at Nov. 1980, the short term pH of rain will change to value ranging from 4.6 to 4.2 owing to HLLV launch. On the other hand, long-term effects owing to nearly 400 HLLV launches per year is negligible because of the change of the pH value is 0.07 and it would not be detectable. An increase of water acidity might also be caused by the possible acidification of precipitation. As we have mentioned abo ve, the HLLV launch center must be located by the beach. Therefore, a great deal of exhaust pollution would drop into the sea near the center. The cumulative effect of the pollutant must not be ignored. Moreover, there would be the possibility that the pollutant destroy the ecosystem in the sea.. Potential Launch Failure As the number of launches increase, the number of failures will also increase. The effects of launch failure will be similar to those of aircraft's accidents during take off and landing. Therefore a very important issue is the selection of launch site. A sufficient distance should be kept from the densely habituated regions. If the average rate of launch failure is 5%, which is lower than the present
RkJQdWJsaXNoZXIy MTU5NjU0Mg==