Breaking Down the Science of a Hurricane

Alexander-Lakhanpal-hurricane

Hurricane season has devastated communities this year along the Caribbean Sea. Puerto Rico, Florida, and even the Bahamas felt the wrath of these powerful storms. With the number of storms increasing during the season, paired with unprecedented wind strength, understanding the science of how these storms form and why they are so strong.

 

Hurricane 101

It takes various different circumstances for a powerful hurricane to form. If one small ingredient is missing, a storm that could destroy a city can be turned into a rainy day with big clouds. Tropical cyclones, which is an umbrella term for tropical depressions, storms, and hurricanes need the basic ingredients to form. A preexisting thunderstorm, warm water, humid air, and light winds must all be present to be the foundation for a hurricane. These mighty storms need fuel, and that fuel is heat from the ocean. When the surface of the ocean rises to 80°F, that is when trouble begins.

The moisture in the air is what fuels the thunderstorm needed and the winds cannot be strong enough to hinder the shaping of the hurricane. When all of these factors meet up perfectly is when a power thunderstorm is able to take off. Depressions are normally the spark of growing into something greater.

 

This 2017 Season

This hurricane season has proved to be one of the most aggressive in the history of weather. Not since 2005, the top busiest year for Atlantic hurricanes with 28 storms, has the U.S. been affected by this many storms. This season alone has had 13 identified storms so far. For this season to be put into the books for the top 15 hurricane years, it needs two more named storms by November 30th, 2017.

The true source, specifically, for this year’s intense season is due to the Multi-Decadal Oscillation (AMO). We are currently in the warm phase of the AMO which allows for a lack of vertical wind shear paired with increased surface temperatures on the ocean. This creates frequent storm developments. This warm AMO phase has been active since 1995 and prior to the was a cold phase the lasted between the years 1971 to 1994.

The other factor that is making this season so brutal is its ability to direct itself so well. An area of dominant subtropical high pressure, known as the “Bermuda High” is located above the Atlantic. It forces winds to turn clockwise and pushes them to directly hit towards the Caribbean, Gulf of Mexico and the east coast. It is essentially a steering wheel towards land.