Hurricane Alley
Encyclopedia
Hurricane Alley is an area of warm water in the Atlantic Ocean
stretching from the west coast of northern Africa to the east coast of central America
and Gulf Coast
of the southern United States
. Many hurricanes form within this area. The temperature of the Atlantic in Hurricane Alley has been steadily growing warmer over the past decades, which most climate scientists believe accounts for the increase in hurricane activity.
The area between 10° and 20°N create the most hurricanes in a given season because of the warmer temperatures. Hurricanes do not form outside this range because the Coriolis Effect
is not strong enough to create the tight circulation needed and above this range the temperatures are too cool. The waters are only at the necessary temperatures from July until Mid-October. In the Atlantic this is the height of the season
. Water takes longer to heat than land, which is why it takes so long for hurricane alley to be at the right temperature for hurricane development and lasts so late.
Since hurricanes rely on sea surface temperature, sometimes an active season in the beginning becomes quiet later. This is because the hurricanes are so strong that they churn the waters and bring colder waters up from the deep. This creates an area of the sea the size of the hurricane, which has cooler waters, which can be 5-10°C lower than before the hurricane. When a new hurricane moves over the cooler waters they have no fuel to continue to thrive, so they weaken or even die out.
The relationship of 'hurricane alley' to climate change
is a difficult topic. Recent scientific evidence suggests that hurricane intensity may be increasing due to warmer tropical sea surface temperature, but the connection to Atlantic hurricane frequency is less conclusive. There is a debate as to whether climate change is causing more severe storms, but more research is needed into hurricane dynamics.
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
stretching from the west coast of northern Africa to the east coast of central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
and Gulf Coast
Gulf Coast of the United States
The Gulf Coast of the United States, sometimes referred to as the Gulf South, South Coast, or 3rd Coast, comprises the coasts of American states that are on the Gulf of Mexico, which includes Texas, Louisiana, Mississippi, Alabama, and Florida and are known as the Gulf States...
of the southern United States
Southern United States
The Southern United States—commonly referred to as the American South, Dixie, or simply the South—constitutes a large distinctive area in the southeastern and south-central United States...
. Many hurricanes form within this area. The temperature of the Atlantic in Hurricane Alley has been steadily growing warmer over the past decades, which most climate scientists believe accounts for the increase in hurricane activity.
How hurricanes form
Hurricanes form over tropical waters in areas of high humidity, light winds, and warm sea surface temperatures. These areas which were described above are usually between the latitudes of 8° and 20° north. The perfect temperature for a hurricane is approximately 26 °C. This temperature has been set as a standard. If the water is colder the hurricane will most likely weaken, but if the waters are warmer rapid growth can occur.The area between 10° and 20°N create the most hurricanes in a given season because of the warmer temperatures. Hurricanes do not form outside this range because the Coriolis Effect
Coriolis effect
In physics, the Coriolis effect is a deflection of moving objects when they are viewed in a rotating reference frame. In a reference frame with clockwise rotation, the deflection is to the left of the motion of the object; in one with counter-clockwise rotation, the deflection is to the right...
is not strong enough to create the tight circulation needed and above this range the temperatures are too cool. The waters are only at the necessary temperatures from July until Mid-October. In the Atlantic this is the height of the season
Hurricane season
Hurricane season refers to a period in a year when hurricanes usually form. For more information see: Tropical cyclone#Times.* The Atlantic hurricane seasonFor a lists of past seasons, see:...
. Water takes longer to heat than land, which is why it takes so long for hurricane alley to be at the right temperature for hurricane development and lasts so late.
Since hurricanes rely on sea surface temperature, sometimes an active season in the beginning becomes quiet later. This is because the hurricanes are so strong that they churn the waters and bring colder waters up from the deep. This creates an area of the sea the size of the hurricane, which has cooler waters, which can be 5-10°C lower than before the hurricane. When a new hurricane moves over the cooler waters they have no fuel to continue to thrive, so they weaken or even die out.
The relationship of 'hurricane alley' to climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
is a difficult topic. Recent scientific evidence suggests that hurricane intensity may be increasing due to warmer tropical sea surface temperature, but the connection to Atlantic hurricane frequency is less conclusive. There is a debate as to whether climate change is causing more severe storms, but more research is needed into hurricane dynamics.
Further Reading
- http://www.nhc.noaa.gov/climo/
- http://csc.noaa.gov/hurricanes/#
- http://earthobservatory.nasa.gov/Features/DelicateBalance/balance.php
- http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MYD28M