Atmosphere Attenuation [hlp]

Hello Everyone;
What is relation between atmosphere attenuation and frequency of the microwave wave? Is there any function or graph?

I suggest Radio Propagation topic at wikipedia.

Well, i may give you this relation: (suitable for atmospheric attenuation that affects radar range)

Γ=0.438M / λ2 [dB/km]

where is:
Γ - atmospheric attenuation
M - quantity of vapor in the air (measured in gr/m3)
λ - wave length in cm

This relation is empirical and stands for next conditions:
hidrometeors are relatively small size (clouds, fog, ...)
1/2 ≤ λ ≤ 10 cm
t = 18 °C

There is a relationship between atmospheric attenuation and frequency. Also there is a relationship between atmospheric noise and frequency due to water mosture.

There's plenty of charts on internet. Let me know if you need addresses.