- "Not only is it extremely hot out there, but for the last half an hour the barometric pressure has been dropping and the wind speeds have increased significantly."
- ―A Hologram of Rodney McKay[src]
Atmospheric pressure is the force per unit area exerted against a surface by the weight of air above that surface in the Earth's atmosphere. It is measured by a barometer, hence it is called Barometric pressure. In an alternate timeline, where Lt. Colonel John Sheppard traveled 48,000 years into the future, a Hologram of Dr. Rodney McKay told him that the barometric pressure outside had dropped and the winds were getting stronger indicating that a violent storm was coming. (SGA: "The Last Man")