Canavu Starline Posts The Invisible Force While we often perceive air as weightless, the atmosphere is a fluid that exerts a tremendous amount of pressure on everything it touches. At sea level, the average atmospheric pressure is approximately 1013.25 millibars (hPa). This “weight of the sky” is not static; it varies based on temperature, altitude, … Continue reading The Weight of the Sky: Atmospheric Pressure and the Gradient Force