Standard atmosphere

After searching quite a bit for practical formulae to do this job, I finally took the excellent work of Hugo Lorente, published by AMSAT Argentina in the proceedings of the 1er Simposio de Comunicaciones Satelitales y Digitales (22/23 de setiembre de 1990), and derived the ones that are below.
(Each case presents the theoretical formula, and then a version with all constants replaced by their values).

For those who are not interested in the formulas, I've published a an on-line calculator on another page.

OJO: All formulas use metric units! (like hectoPascal (hPa), g in m/s², height in meters (m), etc.

Presure > 226.3203 hPa
54.749 < Pressure < 226.3203 hPa
8.68 < Pressure < 54.749 hPa
Pressure < 8.68 hPa

---

To complete the list, I'll include the original (inverse) formulas below:

Height < 11000m
11000m < Height < 20000m
20000m < Height < 32000m
32000m < Height

Where:

T₀

Temperature at 0 m (288.15°K)

T₁₁

Temperature at 11000 m

T₂₀

Temperature at 20000 m

T₃₂

Temperature at 32000 m

a

Temperature at sea level

b

Temperature decrease per m altitude:

         0 - 11000m   -0.0065°K/m
     11000 - 20000m   Stable
     20000 - 32000m   +0.001°K/m
     32000 - 47000m   +0.0028°K/m

g

9.80665 m/s²

rho₀

Air density at 0 m (1.225 kg/m³)

P₀

Pressure at 0 m (1013.25 hPa)

---

(c) John Coppens ON6JC/LW3HAZ

mail