Barometer: What is it, what is it for, how it works and types

A barometer is a instrument used to measure atmospheric pressurewhich is the weight that air exerts on the surface of the earth. This device is key in meteorology, since changes in atmospheric pressure can indicate variations in the weather, such as storms or good weather.

A barometer mainly serves to predict changes in the climate by measuring atmospheric pressure. This information is valuable for meteorologists, navigators, pilots and any person who needs to anticipate climatic conditions.

• When atmospheric pressure increases, it is usually a sign of good weather or clear skies. On the contrary, a pressure drop indicates the possible arrival of bad weather, such as rains or storms. Therefore, barometers are useful for provide short -term climatic changes.
• In aviation, the barometer is necessary to Determine the altitude of aircraft. Airplanes use a variation of the barometer called aneroid altimeter, which measures air pressure and makes it a height reading. This helps pilots maintain the right altitude during the flight.
• In the sea, a sudden change in pressure can be a sign that a storm or bad weather is coming. Navigators can use a barometer to Plan your route safely and avoid dangerous conditions.
• They are also used in Scientific studies on climate and atmosphere. For example, researchers can analyze pressure patterns in different parts of the world to study more complex weather phenomena, such as hurricanes or cyclones.

The operation of a barometer depends on the type of instrument, but in general terms, they all measure atmospheric pressure, which is the weight of the air that surrounds us. Let’s see how the two main types of barometers work: Mercury and Aneroid.

Mercury barometer

The Mercury Barometer has a Glass tube closed by one end, which is filled with mercury and is invested in a container that also contains mercury. The open part of the tube is submerged in the container.

The Atmospheric pressure exerts strength on mercury in the containerpushing it up inside the tube. The higher the atmospheric pressure, the higher the level of mercury within the tube, and when the pressure decreases, the low mercury level.

The height of the mercury column, measured in millimeters or inches, indicates atmospheric pressure. For example, a typical value of normal pressure at sea level is approximately 760 mm of mercury (mm Hg). Changes in this height are used to anticipate climatic variations.

Aneroid barometer

The aneroid barometer has a small Metal capsule sealed and flexible called “Aneroid capsule”. This capsule is empty of air and is very sensitive to changes in atmospheric pressure. When air pressure increases, compress the capsule; When the pressure decreases, the capsule expands. This compression or expansion movement is very small, but enough to move a series of levers and gears inside the barometer.

The movement of these mechanical pieces is amplified and transferred to a Needle that moves on a graduated scale. Thus, the Aneroid barometer indicates atmospheric pressure without liquids.

There are several types of barometers, each with different mechanisms and applications. How we have already analyzed the main ones that are those of Mercury and the Aneroidswe will explain how the other types are:

Digital barometer

With the advance of technology, digital barometers have become increasingly common. These electronic devices use advanced sensors to measure atmospheric pressure already They are integrated into other devicessuch as mobile phones, smart watches or weather stations.

They use Electronic sensors that detect changes in air pressure and transform that information into a digital reading. Some digital barometers can also connect to networks to send or receive weather data.

Barograph

The baragraph is a variation of the aneroid barometer that not only measures atmospheric pressure, but also records its changes in time. A baragraph uses the same principle as the aneroid barometer (a capsule that deforms with the pressure), but is equipped with a rotating drum covered with paper. A pen connected to the capsule mechanism draws a line on paper, registering pressure changes over time.

Water barometer

It is a more rudimentary barometer that Use water instead of mercury. It is also known as Goethe Barometer, in honor of the German poet and scientist Johann Wolfgang von Goethe, who popularized this design.

It consists of a bottle with water and a sealed opening where a straw or tube is introduced. When atmospheric pressure increases, water in the tube descends; When the pressure decreases, the water level in the tube rises. The problem is that It is not very preciseand is used more as a scientific demonstration or decoration than as a serious weather tool.

Cubet or Siphon Barometer

This type is a less common variation of the mercury barometer. Use one Mercury column In an open tube at both ends, which gives it a simpler form, but less precise than the traditional mercury barometer.

It works similar to the mercury barometer, but with a simpler design that includes a siphon -shaped tube. The difference is that this barometer allows you to observe the level of mercury directly without the need for a sealed column. Is less accurate and has been replaced almost completely by more advanced versions.

Now that you know what a barometer is and what it is for, you may be interested in reading this article about the elements and factors of the climate.

If you want to read more articles similar to Barometer: What is it, what is it for, how it works and typeswe recommend that you enter our category of other environment.