Measuring air pressure is important both in weather forecasting and in many industrial applications.
In meteorology, air pressure and its changes relate to low and high-pressure fronts and their movements. A rapid drop in air pressure indicates an approaching storm or rain front, while increasing pressure brings the promise of clearer skies and sunshine.
In industrial applications, pressure is measured in laboratories and life science applications, for example.
Vaisala’s proprietary BAROCAP® micromechanical sensor uses dimensional changes in its silicon membrane to measure pressure. As the surrounding pressure changes, the membrane bends, thereby changing the height of the vacuum gap inside the sensor.
The opposite sides of the vacuum gap act as electrodes, and as the distance between the two electrodes increases or decreases, the sensor capacitance changes. The capacitance is measured and converted into a pressure reading. Read more about Vaisala’s BAROCAP® technology here.
The BAROCAP® sensor’s properties – good low temperature dependence and superior long-term stability – are the result of its single-crystal silicon material.
The capacitive structure gives the sensor its wide dynamic range, very fast response time and provides a built-in mechanism for overpressure blocking.
Vaisala’s pressure offering includes digital barometers and barometric pressure sensors for measuring both barometric pressure and process pressure in industrial applications. BAROCAP® barometers operate over a wide temperature range and perform reliably even in highly demanding applications such as professional meteorology and aviation.
Vaisala offers also multi-parameter products, combining pressure measurements with dew point, humidity and temperature data.
Barometric pressure measurement has a wide variety of applications within meteorology. It is commonly used in weather, aviation, hydrology, and agrology applications.
According to the World Meteorological Organization (WMO), analyzed pressure fields are a fundamental requirement of meteorology. It is one of the key parameters for numerical weather models as pressure data is required for defining the high and low pressure systems.
For numerical weather modeling it is imperative that these pressure fields are accurately defined as they form the basis for all subsequent preconditions of the state of the atmosphere. Typically a high pressure system indicates nice weather and low pressure system predicts precipitation or cloudy conditions. Thus, accurate atmospheric pressure measurements are crucial.
Barometric pressure is also a crucial parameter in aviation applications where it is used to set the aircraft altimeters. Therefore, it is used as operational safety instrument in aviation systems.
Barometric pressure data is also required in several industrial applications. It is measured in pressure-sensitive industrial equipment, such as laser interferometers and lithography systems, engine-testing benches, and in exhaust-gas analysis.
Metrological applications include laboratory pressure standard measurements and environmental monitoring in calibration laboratories.
Pressure measurements can be critical also in regulated life science and high technology cleanroom applications. In these applications, continuous, documented and redundant data is a required to meet regulations.