What Causes Tsunamis
A Hurricane event is a massive circulating storm of warm core, low pressure air masses, which forms upon tropical oceans. Tropical means, those areas of earth that exist between tropic of cancer and tropic of Capricorn. These storms are denoted in the south Asian region as cyclones, in the Asia pacific region as typhoon, while in the American region as hurricanes.
Tropical oceans, having received greater solar radiation than other regions of the world, warm up the most in summer. This results in evaporated, low pressure, moist air masses in the atmosphere.
We all know low pressure system is indicative of turbulent weather with lots of rainfall but, what is a warm core in a hurricane?
After the warm liquid water turns into gas and rises up into air it moves through a cool environment. It is a fact that for every 100 meter ascension, the temperature drops down to 0.7 c. The reason being, the earth surface absorbs more solar heat than atmosphere.
Upon reaching the dew point temperature, a threshold point where gas condenses to water droplets, moist air masses starts to form clouds.
A process called ‘latent heat of vaporization’ comes into play here, which is a cause of a warm core formation in the middle of a storm. When a substance changes its state from gaseous to liquid state it is natural for it to release lots of heat .This condensation/cloud formation process then warms up the surrounding air masses.
Another source of a warm core is adiabatic process, which is a pressure build up or compression on the hurricane system by nearby circulating air masses. According to laws of thermodynamics in physics, when a system is compressed, it warms-up gaining internal energy in the process.
So these two, latent heat and adiabatic processes build up a warm core in the center of a hurricane.
Also Read: What causes Earth Quakes?
Now we discuss hurricane cycle:
In the beginning up of a low pressure system, there is a tropical depression -if seen from a satellite image- which tends to be organised, circulating cloud system of winds reaching up to 30 miles/hour.
Between the 30 M/h and 70 M/h wind speeds, the storm is upgraded to a tropical cyclone and at this point, it is given a specific name by the climatologists.
If the air pressure slumps further down in the atmosphere, more organised and strengthened storm rotation cycle is noticed with winds blowing up to 74 M/h. This is the first phase of a hurricane, if seen from space, the central core in the hurricane would look like that of an eye.
According to Saffir Simpson intensity scale, hurricanes are characterized among 5 categories, with rank 1 storm having wind speed of 74M/h, while rank 5 storm wind reaching up to 140 M/h.
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