Have you ever wondered what the weather will be for your picnic or walk in the park? Oftentimes our outdoor activities can be ruined because of bad weather. Rain, storms and wind can spoil the fun and make us get inside. But with a barometer in hand, you now have a simple yet effective tool that can track sudden weather changes. This will help you decide if you’re going fishing or will go out in the garden to do some work.
What are Barometers?
Have you ever wondered what a barometer actually is? Well, this is a device or a scientific instrument that’s used to measure atmospheric pressure also known as barometric pressure. The atmospheric pressure is actually the layers of air around our planet. These layers have their own weight and due to gravity, that’s pulling it towards the ground, it weighs on everything it touches. Barometers measure this pressure.
When there are changes in the atmospheric pressure, there will be changes in the weather as well. That’s why meteorologists use barometers to predict any short-term changes in the weather. If there’s a rapid drop in atmospheric pressure, it means that you’ll face a low-pressure system. In most cases, this means rain, wind or cloudy weather.
High-pressured areas make the air move. This creates an area with cool and dry air and almost no clouds. The units of measurement are called atmospheres or bars. One atmosphere equals the average air pressure at sea level at a temperature of 15 degrees Celsius.
As altitude rises, there are fewer atmospheres because the air is less dense and under less pressure. The number of atmospheres and air density both rise as altitude decreases. If you want to get an accurate reading of the atmospheric pressure, you should adjust the barometer according to the changes in altitude. You can do this at home as well. You can choose from a wide variety of stylish and functional wall barometers and have your own prediction device.
Who Invented Barometers?
The person who invented the barometer was the Italian scientist Evangelista Torricelli in 1643. His inspiration was Galileo Galilei who invented the thermometer. It all started as an experiment by using a tube of water. However, water is very lightweight, and it needed a glass tube that was very long to measure the pressure right.
Torricelli had to define the characteristics of air pressure before he created the barometer. He created an experiment that demonstrated that water would stop rising when the forces acting on it were evenly balanced. This was inspired by Italian miners whose water pumps couldn’t raise the water after a certain height. The 2 main forces were the force of air pressure and water in the tube. But, many people in the scientific community couldn’t understand or accept this because they believed air didn’t have any weight.
In 1643 Torricelli added mercury at the bottom of a small glass tube (mercury is much heavier than water). So, when the atmospheric pressure increased, the mercury forced its way up the tube. There were markings on the side of the tube, and they showed how many atmospheres were needed to move the mercury up.
Types of Barometers
Mercury Barometer
A mercury barometer is a glass tube with one open end and a reservoir filled with mercury. This is also the oldest barometer ever created. The weight of the mercury will cause a vacuum at the top of the tube. This means this barometer works by balancing the atmospheric pressure and the mercury weight in the tube. The mercury levels will drop if its weight is heavier than the air pressure.
Aneroid Barometer
Lucien Vidi, a French physicist, created the aneroid barometer in 1844. This barometer has a metal chamber that’s sealed, and it expands and contracts in response to the surrounding atmospheric pressure. The chamber’s expansion is measured with mechanical tools. It looks a lot like a regular clock. One hand moves either clockwise or counterclockwise to give you the exact number of atmospheres at the moment.
This is a great example of wall barometers because there are words such as rain, fair, change, dry and stormy written around it, so that everyone can understand the barometer. Since their invention, these barometers replaced the mercury ones because they were simpler to use, cheaper and more convenient to carry around. There are aneroid barometers called barographs. They use a mechanical tool to monitor the changes. They’re connected to needles and these needles make marks on graph paper.
Water-Based Barometer
This is a barometer made of a glass container that’s half filled with water. There’s a narrow sprout that’s open to the atmosphere and it’s connected to the glass container below the water level. When the air pressure is high, the water level in the spout will fall below water level and vice versa.
Digital Barometer
This is the most accurate type of all of the weather barometers. It can measure complex data with great accuracy and speed. The barometer archives and stores this data, and it is also possible to download it to a computer for additional research. Scientists use it when they conduct experiments or when they want up-to-date information.
What is it Used For?
Metrologists are the ones who use barometers the most. They use it to predict short-term changes in the atmospheric pressure. When there’s low pressure, it means there will be a drop in temperatures and possible rainfall. But if the pressure rises, it’s usually a signal for good, clear weather. But you don’t have to be a meteorologist to be able to read barometers.
If you have one at home, you can check it the morning before your trip. This way you’ll know if it’s a good idea to get going or stay in the house for a while. Some people don’t want to get caught in storms on the road, so a barometer is a great prediction tool to have around the house. Plus, if a huge storm is coming, you’ll be able to see it and prepare for any possible outcome.
Having a barometer at home can also be beneficial if you’re a gardener. By monitoring it closely, you’ll know if some of your more fragile plants need protection from strong storms of high temperatures. You can also see if rain is coming and skip the watering today. Overall, they provide valuable insight into the weather locally.
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