Not to mention there is virtually no CO2 in the atmosphere.
You are correct:
Below is the composition of air in percent by volume, at sea level at 15 C and 101325 Pa.
Nitrogen — N2 — 78.084%
Oxygen — O2 — 20.9476%
Argon — Ar — 0.934%
Carbon Dioxide — CO2 — 0.04%
Neon — Ne — 0.001818%
Methane — CH4 — 0.0002%
Helium — He — 0.000524%
Krypton — Kr — 0.000114%
Hydrogen — H2 — 0.00005%
Xenon — Xe — 0.0000087%
Ozone — O3 — 0.000007%
Nitrogen Dioxide — NO2 — 0.000002%
Iodine — I2 — 0.000001%
Carbon Monoxide — CO — trace
Ammonia — NH3 — trace
Note they never talk about the temp, elevation, or pressure anytime they talk CO2. All 3 impact the %s.