Home | Reference-and-education

Lightning - The Key To Thunder 

Understanding The Common Thunderstorm

Gaining a basic knowledge of the thunderstorm requires an understanding of the two parts of this common word. Thunder, a word that is very similar in several languages other than English, is closely associated with the mythical god Thor. At one time it was believed this being caused the loud sounds in the sky we know as thunder.

The word "thunder" actually means a loud noise caused by the expansion of air that is heated by lightning. Combined with the usual conditions of a storm, the thunderstorm can be one of the most impressive weather events we experience. A "storm" is basically a disturbance of the atmosphere, with winds of extreme force and direction. This is often accompanied by rain, hail, thunder or lightning.

These dramatic events occur thousands of times each year. Some estimates show 40,000 thunderstorms around the world annually. The necessary conditions for thunderstorms exist primarily near the equator and in the middle latitudes, such as in the U.S. Midwest and in the southern states.

If the correct mix of moisture, lift and instability are present, conditions are right for a thunderstorm. But a thunderstorm has a distinct life of its own, as it passes through three stages: a developing stage in which cumulus clouds play a large part; a mature stage, the actual "life" of a storm; and the dissipation stage, when the power of the storm grows weaker.

The first stage of a thunderstorm is characterized by the upward movement of moist, warm air. This mass of air moves into a cooler segment of air and cools. As the water vapor is condensed by cooling, cumulus clouds begin to form. These are the obvious signs of a developing storm that attract the attention of storm chasers.

As the storm goes into its mature stage, the rising air finds a barrier often known as the tropopause. The cloud begins to spread at the top, providing the anvil shape that is so characteristic of a major thunderstorm. In more severe conditions, the rising air may push through this barrier and enter the next level above the earth's atmosphere – the stratosphere. It is here that very small particles of water form into raindrops and may freeze. Should the storm's upward air movement be strong enough, these ice particles can be held until they form larger ice chunks that fall to earth as hail.

One of the key elements of a storm, of course, is lightning. Electrical discharge in the atmosphere produces visible light that also heats the air. The expansion of air may be sufficient to produce shock waves audible to the human ear – thunder. Scientists are still trying to uncover the secret behind the opposing electrical charges that cause lightning, but they are looking closely at the contribution of ice crystals and rain as "carriers" of these charges. If the electrical charge builds to the correct strength, a discharge can take place in the cloud or between clouds. The discharge from a cloud to the earth is what we see as a lightning bolt (actually a small percentage of all lightning activity). Thunder is produced when the air near a lightning bolt is heated enough to cause it to expand and contract rapidly.

Article Source: http://www.uberarticles.com/articles

Focusing on informating about lightning, Vince Paxton wrote predominantly for www.alicante-spain.com . On his site you can see his comments on weather in benidorm spain and lightning.

This article is licensed under a Creative Commons Attribution-No Derivative Works 3.0 Unported License, which means you may freely reprint it, in its entirety, provided you include the author's resource box along with LIVE VISIBLE links (without "nofollow" tags).