Prediction of the future has always fascinated and excited people through horoscope, palmistry, Extra Sensory Perception (ESP), Tarot Reading and scrying etc, though a huge fraction of the population does not believe in it, are scared enough to know what is hidden in the future or find it as a joke and then, there are extremists who are completely against it and label it as obnoxious.
But as a matter of fact, even if we accept it or not, we are actually getting predictions of future daily and we also tend to believe it and rely on it too. Taken aback? Well, don’t we all regularly check the default weather widget to know the weather of today, tomorrow and the coming days and weeks? Weather Forecasting is nothing different than predictions of future. The word ‘forecast’ itself means predicting the upcoming event.
Though there are few differences, like firstly, weather forecasting is limited to estimating future weather only rather than life events. Secondly, the weather is predicted through weather instruments rather than through horoscopes or other ways.
Weather is comprised of temperature, pressure, wind, humidity, and precipitation, and these elements are measured differently through different measuring instruments.
Temperature is all about how hot or cold the weather is, and to measure temperature, the instrument used is a thermometer. A thermometer is a tube that consists of mercury or alcohol, which expands when the temperature is hot. We measure the temperature by comparing the expansion with the attached scale in the thermometer.
For the proper measure of the atmosphere’s temperature, a mercury thermometer is not enough. The advancement of technology has led to the invention of electronic thermometer which has led to the enhancement of the accuracy.
The second element, which is the air pressure, can be predicted by a barometer. Pressure is basically the force exerted on a surface. If the barometer is indicating high pressure then there would be a dry and sunny day, while a low pressure means cloudy, wet or snowy day.
Most of the time we say the weather is very humid if we feel too hot and sweaty, this is because there is moisture in the air. Moisture in the atmosphere means a high rate of water molecules in the air. Rate of humidity can be measured by the hygrometer. Hygrometer was basically invented two hundred years back and one if its type is Psychrometer, which measures humidity with the help of two thermometers.
When it comes to wind, two things are noted about it, its speed and its direction. An anemometer measures the speed of the wind so does it notes the wind’s direction. There are three to four cups attached on an anemometer that determine the speed of the wind, while the wind vane on the instrument finds out the direction of it.
Precipitation in simple words means rain fall and snow. Precipitation is measured by a rain gauge, which is basically a simple can and the water collected from the rain is measured by the depth of it with the help of a scale. However, a rain gauge lacks accuracy because the water can be collected more easily rather than snow. Also, if the temperature is high, the water may get evaporated from it even before it is measured, leading to wrong measures.
These five elements of the weather are measured with the help of different instruments and then do you find the present and the future forecasts of the weather on television news, websites and weather apps and widgets.