/* Calculates the sea-level pressure (in hPa) based on the current altitude (in meters), atmospheric pressure (in hPa), and temperature (in °C) */
float pressureSeaLevelFromAltitude(float altitude, float atmospheric, float temp)
/* Calculates the sea-level pressure (in hPa) based on the current altitude (in meters), atmospheric pressure (in hPa), and temperature (in °C) */
float pressureSeaLevelFromAltitude(float altitude, float atmospheric, float temp)
{
  return atmospheric * (float)pow((1.0F - (0.0065 * altitude) /
          (temp + 0.0065 * altitude + 273.15F)), -5.257F);
}