Michel Vanhueghe,you were very helpful.Why do storm chasers use barometers?Does it vary depending on altitude?

Question

Michel Vanhueghe,you were very helpful.Why do storm chasers use barometers?Does it vary depending on altitude?

Answer 1

Indeed, the barometer varies with altitude! In my aircraft, I have a altimeter that shows my altitude. In fact, it is simply a barometer. But to work properly, I have first to adjust it to the local pressure, or more correctly, to the local pressure adjusted to sea level: what we call QNH in aviation.

But if storm chasers use barometers, it is simply to find the way to the lowest pressure since that's where there center of the tornado will be.

You wrote 'storm chasers' but I think you meant 'tornado chasers.' Tornadoes are simply very local, concetrated and strong low pressures; similar to a 'storm' but more local.

Tornadoes can happen anywhere in the world but it is most common in the US because of the size of the continent, the Rocky Mountains and the Gulf of Mexico. It makes it possible to have very warm air under very cold air when the polar front extends much south. Those are ideal conditions for extreme weather. Remember, the intensity of a storm in not due to the temperature but the difference of temperature between the surface and the top of the atmosphere.

Again, think of it as a chimney in a house. If it is very cold outside and the fireplace is very warm, then air will rise very fast in the chimney.