Earth density model (PREM):
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download
http://ds.iris.edu/spud/earthmodel/9991844

wikipedia
The preliminary reference Earth model (PREM) is a one-dimensional model representing the average Earth properties as a function of planetary radius. It includes a table of Earth properties, including elastic properties, attenuation, density, pressure, and gravity, as a function of planetary radius.

Atmospheric model (US76):
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data collected from http://www.braeunig.us/space/atmos.htm (especially for the density between 1000km - 36000km altitude)
