how does a tornado happen?
A tornado is a violent, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud. The formation of a tornado involves a complex interaction of atmospheric conditions, so let's break it down step by step:
1. Moisture and instability: A tornado typically forms in conditions where warm, moist air meets cool, dry air. This creates an unstable environment, with warm air wanting to rise rapidly.
2. Updrafts: If there are sufficient updrafts (rising air currents), a thunderstorm may develop. These updrafts begin to pull the warm, moist air upwards.
3. Organized rotation: As the updrafts continue to rise and accelerate, they can start to rotate horizontally due to wind shear. Wind shear refers to the change in wind direction and speed with height. This rotation can be enhanced by the presence of nearby weather systems or boundaries, such as fronts.
4. Tornado formation: If the rotating updraft becomes strong enough, it can begin to extend from the cloud base down toward the ground. This is known as a mesocyclone, which is often characterized by a rotating wall cloud.
5. Development of a funnel cloud: From the mesocyclone, a narrow, funnel-shaped cloud begins to descend vertically. This is called a "funnel cloud" and is not yet in contact with the ground.
6. Tornado touchdown: If the funnel cloud reaches the ground, it officially becomes a tornado. This can happen when it encounters a strong downdraft, which can push the rotating column of air all the way to the surface.
It's important to note that tornadoes are still not fully understood, and the precise mechanisms of tornado formation and intensity remain subjects of ongoing scientific research.