Types of Weather Instruments and Their Usage
Until the 18th century, people were utterly dependent on sensory observations for any weather data, i.e., they understood the wind direction through the movement of leaves or estimated the time of rain through the number of clouds in the sky.
Now, the time has changed. Today, we are blessed by modern technology which includes different weather instruments that help us to accumulate accurate weather data.
Meteorology is the science of atmosphere that includes both the weather and the climate. This study includes some methodological instruments that help to collect physical, dynamic and chemical state of the atmosphere.
Here, I am going to give a clear concept about some most important meteorological or weather instruments and their usage that will make you realize how blessed we are because of these instruments and how they help to collect accurate weather data.
Types of Weather Instruments
There are different types of instruments for measuring different parameters. For example, Atmospheric pressure is measured by the barometer, again the temperature is measured by thermometer, etc.
Jumping into the main topic, let’s talk about different individual instruments along with their usage.
Sometimes we feel hot, again occasionally cold. This occurs due to temperature change. Through the feeling of hot and cold, we can tell is it summer or winter but for knowing the exact temperature, a device is required and that is a thermometer.
The thermometer is a device that is used for measuring the temperature or the temperature gradient. This temperature can be used in industry, in meteorology, and even in medicine.
This device has two important things that help in measuring the temperature. The first one is a sensor that uses different physical parameters like the expansion of different states of matter for sensing the change and the second one is a converter that converts the change of temperature into a numerical number.
There are different types of thermometers considering through which liquid it is filled. In weather stations, mainly mercury-filled thermometers are used.
Mercury filled thermometers can measure the temperature from -35 to 40 degree Celsius. It has a scale division of 0.2 degrees. But if the temperature is less than -35 degree Celsius, then this thermometer cannot give an accurate result and becomes unreliable.
For measuring the temperature under -35 degree Celsius, alcohol-filled thermometers are used. This type of thermometers can measure from -65/-75 degree Celsius to 20/25 degree Celsius.
The thermometers use different physical parameters like the expansion of different states of matter for measuring the temperature.
A barometer is an instrument that measures the atmospheric pressure. It measures the pressure in measurement units called bars or atmospheres.
The earth is wrapped by layers of air which is called atmosphere. The air has weight, and it presses everything against gravity. A barometer measures this pressure.
When barometer shows low-pressure, it means that the weather is rainy, windy or cloudy and when the pressure is high, it means that the weather is fair.
There are different types of barometer like the mercury barometer, aneroid barometer, and the digital barometer. Among these three, the digital barometer is the latest one that gives the accurate data.
It is a device that measures the amount of water vapor in the air or the humidity. There are different types of hygrometer considering their different principles.
Hygrometer mainly can be divided into two types. They are dry and wet bulb psychrometer and a mechanical hygrometer.
Anemometer is a widespread instrument in the wind station. It is used to measure the speed of the wind.
The speed of wind gives a lot of information about the weather. Like; if the speed of the wind is high, it indicates a storm.
So through anemometer, we can determine the speed of the wind which helps us to protect ourselves from many natural disasters beforehand.
5. Wind Vane
A wind vane is also called a weather vane or a weathercock. This is an instrument that is used for showing the direction of the wind.
It has a similar feature like the traditional cockerel design with letters that indicate the points of the compass.
The tool is placed on top of a weather station that gives accurate result about the direction of the speed which provides a lot of information about the changes that takes place in the weather.
6. Rain Gauge
A rain gauge is an instrument used by meteorologists for measuring the amount of precipitation occurred over some time.
They are one of the instruments that are present in most of the weather stations. The rain gauge must be placed at an open place without any obstacle.
The amount of precipitation is measured either manually or by an automatic weather station. The instrument has some limitations. It is impossible for rain gauge to collect rain during a hurricane.
7. Campbell Stokes Recorder
This is a device that records the sunshine and is used for knowing how many hours there was bright sunshine.
It is designed with a glass sphere for focusing the rays coming from the sun. It concentrates into a beam enough for burning paper. If there is any break in the burn line, that indicates that the weather is cloudy.
The extinction coefficient of the atmosphere and the sea water is measured by transmissometer. It also determines the visual range.
This instrument is operated through passing a beam of energy through a propagation medium. A detector that is placed at a distant place receive the energy and measure the amount of it through which it says the coefficient of the atmosphere.
9. Stevenson Screen
A Stevenson screen also called thermometer screen is a shelter of the other weather instruments. It protects the instruments from rain, snow, high wind and even from animals and also from precipitation and direct heat radiation.
It is kept above the ground to avoid strong temperature gradient and encourage free passage of air. It is placed in such a way that it is not destroyed because of heavy wind.
10. Ceiling Projector
It is a device used to measure the height of the base of the cloud above the ground. The projector is normally set at an angle of 90 degree Celsius but sometimes 71 degrees 31 minute may also be used.
The instrument is made up of two components. Among which one is the sight of the spotlight, and the other is the alidade.
The spotlight is of 430 watts which are placed in a secure box where two mirrors are also present. These mirrors are set for producing a high-intensity beam of light that makes a light spot on the cloud base.
A radiosonde is an instrument that is battery powered and used for measuring atmospheric parameters. The parameters include temperature, pressure, wind direction as well as speed.
It is worked by using a rubber or latex balloon filled with helium or hydrogen gas that measures the parameters and transmit them to the receiver in the ground by radio.
The radiosondes can operate at a frequency 403 MHz to 1680 MHz. In most of the radiosondes, there are radar reflectors.
13. Ceiling Balloon
The ceiling balloon has a similar function as the ceiling projector. But there is a difference, and it is the ceiling balloon is the device that measures the height of the base of the cloud during the daytime.
A ceiling balloon is a rubber balloon which is red in color. The principle behind it is the time difference required for the balloon to climb from its release and the time required to disappear within the cloud tells the height.
14. Snow Gauge
A snow gauge is an instrument that is used for measuring the solid precipitation over some time.
The instrument is made of two parts. One of the components is a copper catchment container, and the other one is a gauge itself.
Once the snow is collected, the container is removed. The snow is melted in the tank, and then it is poured in a measuring cylinder that measures the amount of snow collected.
A barograph is a kind of barometer that represents its result in a graphical form. It is used for measuring the barometric pressure, i.e., the atmospheric pressure.
This instrument includes a computer that gives the accurate result of the pressure in a graphical form which will tell the changes that take place in the atmosphere.
A dropsonde is a different type of instrument that is dropped from the aircraft over water to get information about the condition of the storm.
It contains a GPS and pressure, temperature and humidity sensor to gather data on atmospheric profile and the information is passed to the aircraft through the radio transmission, and the data are visible in the computer.
17. Lightning Detector
This is an instrument that detects the lightning that is produced through thunderstorms.
There are three types of lightning detector considering the number of antennas present. They are a ground-based system, mobile-based system, and space-based system.
Lightning detectors don't work alone instead they work along with weather radars. The indicator shows the electrical activity, and the radar shows the precipitation, and together they give a complete result.
18. Automatic Weather Station
This is a digital version of the weather station that is automated. It reduces the human labor and can give much more accurate result than that of the weather station.
The areas where it is not possible for human beings to survive, an automated weather station is the one there that keeps updating the weather change and also awarding beforehand about any natural disaster.
The weather instruments like the thermometer, barometer, hygrometer, rain gauge are the essential instruments present in every weather station.
Through these instruments, we can get the accurate data on weather and can identify even the slightest change in the cold. It is also possible to become aware of any natural disaster.