It's Hurricane Season
If you reside anywhere in the Northern Hemisphere you are probably aware that we are currently in the midst of the hurricane season, which officially starts on June 1st and ends on November 30th, every year.
The hurricanes which originate from both, the Northern Atlantic Ocean and the Northeast Pacific Ocean, peak in late September before starting to taper off. In the Southern Hemisphere the season begins in late October and ends in May, peaking in Mid-February. In this article we go behind the scenes to examine how and why hurricanes happen and, if there is anything we can do to stop them.
While Scientists have been studying hurricanes for only the last one hundred years, there is evidence that these powerful storms have been going on for much longer. In fact, the name hurricane is thought to have evolved from the word 'Hurakan' - One of the gods of the ancient Mayan civilization that inhabited Mexicoaround 900 AD. The Mayans believed that Hurakan caused these storms by blowing his breath across the water. In 1400 AD the Carib Indians, who lived in the West Indies islands re-named the storms 'Hurican', or god of evil
What Are Hurricanes?
Hurricanes also known as cyclones in some parts of the world, are super powerful storms, which gain momentum from winds that help them blow in at speeds ranging from 75 to 225mph, resulting in massive destruction when they hit land.
How Do They Occur?
For hurricanes to occur, the ocean temperatures must be at least 80°Fahrenheit and the atmosphere around it, saturated with moisture. Also, the winds must be blowing in the same direction and the same speed to force the air upward from the surface of the ocean.
What Happens Then?
The warm water creates low-pressure air, causing it to rise. As the air rises, it collects moisture-forming thunderclouds. Meanwhile, cool air displaces the empty space created by the warm air that has risen. As the warm air condenses, it produces even more heat and rises even faster, causing more cold air to rush in. This increases the intensity of the storm. As the hurricane winds rotate, they accumulate water in the center of the storm. This water, called the storm surge, is the most deadly part of the hurricane, because it dumps into any landmass it hits, causing floods and devastation. The bigger the storm surge, the more powerful the hurricane.
The Corriolis Effect
When a hurricanes first begins, the rising winds blow in towards the center of the storm. However, as it grows, it gets impacted by what is known as the 'Corriolis Effect'. This is when a force, in this case the Earth's rotation around its own axis, deflects objects on one side. So, while the hurricane is attempting to going straight, the Earth's movement causes it to deflect to the right, forcing it to go counter-clockwise, in the Northern Hemisphere and clockwise in the Southern Hemisphere.
Why does each Hurricane have a name?
Hurricanes are given names, so that scientists can track the storms from start to finish. In the fifties, hurricanes were named after the phonic alphabet, like Able, Baker etc. From 1953-1979, the US Weather Bureau decided to shift to only women's names. Since then, they have alternated between male and female names and now have six different name lists that they alternate each year. If a hurricane causes real major devastation, like Katrina did to New Orleans in 2005 , the name is replaced with another name and never used again.
What can we do to stop them?
Unfortunately, not much. In the past, scientists have tried various inventions to weaken these storms. But they gave up in the 1960's after realizing that the weather patterns were too large to affect. Instead, they changed their focus to understanding how hurricanes form and move, so that they could predict their timing and intensity with greater accuracy. But like other acts of nature, this too remains an inexact science - One that is neither completely predictable nor controllable.
What do the hurricane categories mean?
The hurricane categories, which range from 1-5, are simply a way to gauge their intensity, with 5 being the worst.
The 2008 Hurricane Season
Scientists had predicted that the 2008 hurricane season would be 'well above average' - and as we get into the peak month of September, the forecasts are proving quite accurate, especially on the Gulf Coast. Last week Louisiana, which has barely recovered from the impact of hurricane Katrina was hit by hurricane Gustav, which is estimated to have caused about $2billion USD in damages. As we go to press, the towns of Galveston in Texas and Bridge City and Orange County, in Louisiana, as well as a number of other low lying coastal towns are all under water, thanks to Hurricane Ike. Further inland, more than 4 million people in Houston, Texas, are without power. While Ike has weakened from category 2 to 1 as it moves towards Arkansas, it is still carrying top winds at 90mph and moving north at 18mph. The good news is that thanks to accurate predictions of how severe Ike would be, thousands of people from these areas were evacuated in time, and are safe.
Sources: WeatherWhizkids.com, FEMA.com, Science Daily.com