how to measure a barometer

Now for the fun part.

This mercury barometer was invented back in 1643 by a pupil of Galileo named Evangelista Toricelli.Meteorologists use "millibars" in charting atmospheric pressure and your barometer has a second scale or ring which reads in millibars (mb), or "hectopascals" (hPa). Your barometer is just as accurate a weather forecaster as the TV meteorologist you watch with the news.

Suppose I use a barometer to measure the atmospheric pressure on the ground floor of a building. Many measurements of air pressure are used within surface weather analysis to help find surface troughs, pressure systems and frontal boundaries.. 0-3000 ft., 3000-7000 ft. or 7000 ft and above).When you receive your barometer it must be adjusted before being put to use and a local weather broadcast will give barometric pressure for your approximate location. If the barometer goes up, then that means the weather is going to be fair. If you are using an analog barometer at home or a digital barometer on your cell phone in the U.S., the barometric reading will likely be reported in inches of mercury (inHg). The pressure is shown on your barometer's dial, usually expressed in "inches" referring to "inches of mercury" (inch Hg).

ThoughtCo uses cookies to provide you with a great user experience. These reported readings have already been "corrected" to sea level, thus eliminating any pressure differences due to elevation. The small screw on the bottom right edge is what’s used to calibrate the device; I had to use a small eyeglass screwdriver to do so. A rising barometer indicates increasing atmospheric pressure and a falling barometer indicates decreasing atmospheric pressure.Changes in air pressure are caused by differences in air temperature above the earth, and the temperature of an air mass is determined by its location. Generally the working altitude range covers only about 3000 to 4000 feet. For example, air masses above oceans are typically cooler than air masses above 17th-century French scientist and philosopher Blaise Pascal (1623–1662) discovered that air pressure decreases with height and that pressure changes at ground level can be attributed to the daily weather. This outside set hand will then serve as a reference marker so you can easily see if pressure is rising, falling or steady.Your barometer's reading may not exactly coincide with a broadcast due to difference in location, time of reading and other factors.Note that when using a weather barometer (usually with a scale range between 28 and 31 inches Hg) at a location above sea level, the reading must be corrected back to sea level. Pressure tendency can forecast short term changes in the weather. And while there are some differences in using an aneroid or digital barometer, the principles in measuring and analyzing pressure are the same. So be sure to choose a barometer that has a sensor range factory set for use at your elevation (e.g. As ride the elevator up, the atmospheric pressure decreases. Rachelle Oblack is a K-12 science educator and Holt McDougal science textbook writer.

The accurate measurement of atmospheric pressure is of fundamental importance in meteorology and has particular relevance for the safety of aircraft landing at airports. Its mission is to measure air or atmospheric pressure and indicate its rising or falling.The pressure is shown on your barometer's dial, usually expressed in "inches" referring to "inches of mercury" (inch Hg).

A barometer is a scientific instrument that is used to measure air pressure in a certain environment. These measurements are affected by air density, which changes based on temperature, and height above the Earth's surface.

This is automatically accomplished when you initially match your barometer's reading to that reported by local TV or radio weather forecast.