[Physics Class Notes] on Lightning And Thunderstorm Pdf for Exam

One of the most spectacular elements of a thunderstorm is lightning. In fact, it defines thunderstorm, as the lightning causes thunderstorms. Lightning is the discharge of electricity. The single stroke of lightning heats the air around 30,000 degrees celsius. This heating causes the air in the atmosphere to expand very fast. A shock wave is created by this expansion that turns into booming sound waves: this is known as thunder. An ice crystal which is high within a thunderstorm, it flows up and down in the turbulent air then they crash into each other. Electrons that are the small negatively charged particles are knocked off the same ice as soon as they crash with each other.

Causes of Thunderstorm

An electric storm is also referred to as a thunderstorm or a lightning storm. It’s characterized by an acoustic effect which is known as thunder and the presence of lightning. Thundershowers are known as weak thunderstorms. Cumulonimbus is the clouds due to which weak thunderstorms occur. They are accomplished by strong winds and also they often produce heavy rain and sometimes snow, hail, and sleet. Whereas, some thunderstorms produce no precipitation or no precipitation.

Thunderstorms can become rain bands known as the squall lines and can line up in a series. The strong thunderstorms include one of the dangerous weather phenomena including strong winds, large hail, tornadoes etc, Supercells are one of the most persistent and severe thunderstorms, it behaves the same as the cyclones do. Many of the thunderstorms move with the mean airflow through the layers of the troposphere.  Their vertical wind share sometimes causes diversion at a right angle to the wind shear direction. When the movement of warm air is upward and which is sometimes along with a front causes thunderstorm. When this air rises, it cools and condenses and forms a cumulonimbus cloud that reaches a height of 20 km.

Safety Measures During the Calamity 

Thunder is frightening, and it roars loudly. But it cannot hurt anyone by itself. However, it’s two fearsome companions can be dangerous. Lightning kills on an average 31 people per year in 2006 and 2015, and it has injured 279 people. Hail is another factor that is very dangerous, the chunk of ice falls on the earth’s surface at the speed of 120 mph, and the size of them is from a pea to a grapefruit. So to protect ourselves we need to follow some rules like the 30-30 rule. When we see a lightning flash we should start counting, and if we don’t make it to 30 we should head indoors. Then we should stay indoors for at least 30 minutes after the last thundering sound. 

If we are already indoors, we should avoid using our mobile phones and electronic devices such as computers and power tools, because the electrical wires can conduct electricity. Do not get in contact with water too much like don’t wash clothes or dishes, or we should not take a shower or wash our hands repeatedly. The metal pipes which are usually present in the house can conduct electric currents. If the house has glass windows or doors, high-speed air can shatter them, so we should stay away from the windows and skylight and doors.

What Forms a Thunderstorm? 

A Thunderstorm is defined as a short-lived and violent weather disturbance that is always associated with the lightning effect, thunder, dense clouds, and heavy raining effects. When the layer of warm moist air is raised and gets cooler in the atmosphere then it’s known as a thunderstorm. In the atmosphere, the moisture updraft and it condenses and forms cumulonimbus clouds, which eventually precipitate. The columns of cold air come towards the earth and strike the ground with strong downdraft and strong horizontal winds. The electrical charges accumulate on the clouds at the same time. When the accumulated electrical charge becomes sufficiently large, lightning discharges. 

Shock waves are produced when the lightning heats the air through it, very intensely. These shock waves are heard as rolls of thunder or clapes. On occasions, the thunderstorm causes strong tornadoes also. 

Thunderstorms occur almost in every region in this world. However, in the polar regions, they are rare and infrequent at latitude higher than 50 degrees North and 50 degrees South latitude. Therefore the most prone area to thunderstorms in the temperate and tropical regions. The Florida peninsula is the area in the U.S.A where maximum thunderstorms occur, more than 90 thunderstorms per year. 

Large areas of ascending and descending air cause violent disturbance in earth’s wind system: thunderstorms are not expected to follow these patterns. Technically thunderstorms occur when the atmosphere becomes unstable to vertical motion. Such instability arises when light and warm air is overlain with the cold air. The cooler air sinks under such conditions the cooler air sinks, which raises the warmer air upward. If a sufficient amount of air raises upward, an updrift will be produced. The water will condense and form clouds when the updrift is moist, and the condensation process will create latent heat energy, further increasing the instability.