Hurricane Season 2014: Predictions Call for Below Average Year
To borrow and mangle a quote from Groundhog Day, "Well, it's hurricane season...again." Beginning June 1, anyone who lives along the Gulf of Mexico, Caribbean Sea or Atlantic Ocean starts to cast a wary eye on the tropics. As the temperatures warm up through summer, so does most of the Atlantic Basin, generating the energy necessary to produce tropical storms and hurricanes. But there are many factors that influence the development of those storms, which leads to unpredictability. Still, every year, forecasters trot out their preseason predictions.
Could El Niño keep this hurricane season below normal?
Before getting too deep into those, it's important to note the factors that go into the development of hurricanes. If you live on the Gulf Coast, it is information worth knowing.
Hurricanes are formed when warm, moist air destabilizes the atmosphere and creates a small low-pressure area. This happens over the tropical waters of both the Atlantic and the Pacific. In the case of the Atlantic, that begins to occur in June and lasts until around October, though the season stretches out until December 1.
The primary factors influencing the development of storms include sea surface temperatures, upper level winds and wind shear, dry air, interaction with land and, believe it or not, Saharan dust.
In short, tropical storms need warm water below them and light winds as well as moist, unstable air above. The deeper the warm ocean temperatures go, the better. The more calm the winds, the better. The more unstable the air, the better. Storms also weaken over land, so any interference with land masses, particularly mountainous areas, can degrade or even dissipate storms. Finally, dust that blows off the coast of Africa from the Sahara Desert can block sunlight, cooling the air and preventing the development of storms.
We also happen to be in the middle of a period of increased hurricane activity that began in 1995 referred to as the Atlantic Multi-decadal Oscillation (AMO). This is an atmospheric cycle that leads to increased hurricane activity. It lasts for 25-40 years or more, so we have a ways to go before that changes.