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Atmosphere Structure Explorer

Four modes covering atmosphere layers, temperature inversions, ozone distribution with UV absorption, and Earth's energy balance. Adjust altitude, surface temperature, albedo, and CO₂ levels to see how the atmosphere responds.

Atmosphere Profile

TroposphereStratosphereMesosphereThermosphere020406080100180 K220 K260 K300 KTemperature (K)Altitude (km)5.0 km — Troposphere255.6 K / 54.0 kPa

Controls

Altitude5.0 km
0 km50 km100 km
Surface Temperature288 K (15 °C)

Results

Troposphereat 5.0 km
T=255.6 KP=54.02 kPaT = 255.6 \text{ K} \quad P = 54.02 \text{ kPa}
Temperature
255.6 K
-17.5 °C
Pressure
54.02 kPa
Density
0.736 kg/m³
Gas Composition (% by volume)
N₂
78.08%
O₂
20.95%
Ar
0.93%
CO₂
0.04%
H₂O
0.58%
O₃
0%

Temperature vs Altitude

Pressure vs Altitude

Reference Guide

Lapse Rate

Temperature changes with altitude at a rate called the environmental lapse rate. In the troposphere, temperature decreases at roughly 6.5 K per kilometer.

T=T0ΓhT = T_0 - \Gamma \cdot h

where T₀ is the surface temperature, Γ is the lapse rate (K/km), and h is the altitude in km. The tropopause at 11 km marks the transition to the stratosphere where temperature increases due to ozone absorption of UV.

Barometric Formula

Atmospheric pressure decreases exponentially with altitude. The barometric formula accounts for temperature variation through the lapse rate.

P=P0(1ΓhT0)gMRΓP = P_0 \left(1 - \frac{\Gamma h}{T_0}\right)^{\frac{gM}{R\Gamma}}

where g = 9.81 m/s², M = 0.029 kg/mol (air molar mass), and R = 8.314 J/(mol·K). Pressure drops to roughly half every 5.5 km.

Air Quality Index (AQI)

The EPA Air Quality Index converts pollutant concentrations to a 0-500 scale using breakpoint interpolation.

AQI=IhiIloChiClo(CClo)+Ilo\mathrm{AQI} = \frac{I_{\mathrm{hi}} - I_{\mathrm{lo}}}{C_{\mathrm{hi}} - C_{\mathrm{lo}}} \left(C - C_{\mathrm{lo}}\right) + I_{\mathrm{lo}}

Temperature inversions trap pollutants near the surface by capping vertical mixing. The ventilation coefficient (mixing height × wind speed) determines how well pollutants disperse.

Energy Balance

Earth's energy budget balances incoming solar radiation against outgoing thermal emission. The greenhouse effect traps a fraction of the outgoing infrared.

Eout=σT4(Stefan-Boltzmann)E_{\mathrm{out}} = \sigma T^4 \quad (\text{Stefan-Boltzmann})

Albedo (reflectivity) determines how much sunlight is reflected back to space. Ice and clouds increase albedo, while forests and oceans decrease it. Doubling CO₂ increases greenhouse trapping by roughly 4 W/m².