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Re: U.S. Standard Atmosphere 1976
From: Paul Hirose
Date: 2005 Sep 5, 13:05 -0700
From: Paul Hirose
Date: 2005 Sep 5, 13:05 -0700
Marcel E. Tschudin wrote: > > Comming back again to your kind offer. If the graphs should really be aout > of the U.S. Standard Atmosphere, it would be of particular interest to know > to what air pressure they relate to (at 0m height). Without this > information > the data are unfortunately useless. I now have the U.S. Standard Atmosphere 1976 book from the library. The only temperature vs. latitude graphs I see are for heights of 40, 60, and 80 km. I don't think these are very useful for computing refraction, since above 40 km the air is so rarefied that surely it can't have much effect. The book does say, "In the region 0 to 86 km, latitudinal and seasonal variations about the Standard are observed. In addition, both observation and inference show that extreme departures of considerable magnitude occur. This information is being developed in detail in a series of reference atmospheres which will extend to 90 km. "These reference atmospheres are being prepared under the direction of COESA to replace those described in the U.S. Standard Atmosphere Supplement, 1966. They will include mean monthly atmospheres for each 15° of latitude from Equator to pole. Winter models at 60° and 75°N will depict typical conditions over both North America and Europe. These data will provide information to scientists and engineers on latitudinal, longitudinal, seasonal, and day-to-day changes in atmospheric structure..." I don't know whether or not those reference atmospheres were ever completed. Try a search engine.