Weather instruments are used to give meteorologists information on the behavior of weather patterns and how they affect the atmosphere. They range from simple devices, such as thermometers and rain gauges that measure heat and rainfall, to more intricate instruments,such as the psychrometer, which uses a dry and wet thermometer to measure the relative humidity of the surrounding air. Because weather patterns are part of the heat, pressure and moisture systems of the atmosphere, measuring these variables can help scientists predict the weather.
Basic Principles
Weather instruments are all focused on one primary task measuring atmospheric conditions. Meteorologists are interested in all of the effects that cause different types of weather, including heat, pressure, moisture and wind. The instruments help them measure these variables quickly and precisely. By documenting atmospheric conditions and applying physical laws to their occurrence, scientists can observe and predict weather patterns. While many of their instruments are common and used for many different purposes, some are specific to meteorologists and have particular functions.
Thermometer
Thermometers measure temperature, more specifically, they measure the temperature of the surrounding air. To receive a full set of results, scientists usually take thermometer readings at a set of locations and altitudes. Pockets of air move up and down in the atmosphere, based on how much heat they have. Such movements produce most of the noticeable weather effects, including the movements of rainstorms and the creation of tornadoes. Of course, scientists can also find a wealth of information by measuring the heat of the oceans where weather patterns originate.
Anemometer
Anemometers measure the qualities of the wind that is blowing in the area. They measure wind strength and direction, giving scientists vital information on where and how fast storms are moving. Direction is easy to measure, but the anemometer also shows the pressure built up within the wind and the velocity at which it is traveling.
Barometer/Barograph
A barometer uses air or mercury to measure the pressure of the atmosphere. Atmospheric pressure shifts based on altitude and strong weather effects. Changes in pressure can show scientists what types of weather patterns are developing, providing early warnings signs for such destructive events as tornadoes and hurricanes. In aneroid barometers, the air outside is compared to a pocket of air at a stable pressure within the device, while mercury versions measure the change in mercury, which shifts based on the current pressure.
Psychrometer/Hygrometer
The psychrometer is just one example of how these and many other instruments can be combined to form a set of data on one given effect. Psychrometers use different sets of thermometers to measure relative humidity at a specific location. One device has a dry bulb, and the other has a wet bulb. By measuring the difference between these two thermometers, scientists can pinpoint how much moisture is in the air at the time. Hygrometer is the general name for these systems, and there are other kinds of hygrometers that use different methods to measure humidity, such as the dew point hygrometer.
Tags: weather patterns, atmospheric conditions, heat pressure, heat pressure moisture, measure relative