African dust storms 'the size of continental us’ suppress hurricanes

African dust storms 'the size of continental us’ suppress hurricanes

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HURRICANE BARRY: MODEL SHOWS POTENTIAL DIRECT HIT FOR NEW ORLEANS The NOAA’s National Hurricane Centre (NHC) has closely monitored developing systems in the Atlantic and Pacific oceans this


year. Hurricane season started on June 1 in both regions, and will continue until November this year. Despite starting at the same time, however, they are wildly different in terms of


activity. In the Pacific, the number of storms has totalled at eight, but just two have developed in the Atlantic. RELATED ARTICLES A plume of dust from Africa has settled in the upper


atmosphere around the US east coast throughout the last month, preventing storms - which rely on humidity - from forming in the Atlantic ocean. Jason Dunion, a researcher for the NOAA and


Atlantic Oceanographic Meteorological Laboratory (AOML), explained dust storms from the African west coast often drift over to the US. These dust clouds prevent the humid conditions which


spark storms from developing, and can even “rip” systems apart. Talking to NASA, Mr Dunion said: “The Saharan Air Layer is essentially a huge dust storm that can be the size of the


continental United States.” READ MORE: HURRICANE TRACKER: 'PREPARE YOUR FAMILY' PEAK OF HURRICANE SEASON Hurricane track: African dust storms ‘the size of continental US’ suppress


Atlantic hurricanes (Image: GETTY) “Every three to five days during the summertime, these storms roll off of the African coast. “We think a dust storm has three main components that can


suppress a hurricane. One, it’s got super-dry air. “Hurricanes don’t like dry air in the middle parts of the atmosphere, and that’s exactly what the Saharan Air Layer has. “A Saharan dust


storm also has a very strong surge of air embedded within it, called the mid-level easterly jet, that can rip a storm apart that’s trying to develop.” READ MORE: HURRICANE WARNING: IS


ATLANTIC HURRICANE SEASON ABOUT TO KICK OFF? Dust from Africa has settled in the US upper-atmosphere (Image: GETTY) RELATED ARTICLES “We call that vertical wind shear. And then the third


piece is all this dust.” The dust will dissipate during the second half of August, with a “season within a season” of storms to follow. The US National Weather Service (NWS) has predicted


another 10 to 17 ‘named storms’ could form within the next six weeks. These storms pack winds of 39mph and stronger and can intensify towards 157mph in severe cases. READ MORE: HURRICANE


TRACKER: WHAT IS DIFFERENCE BETWEEN HURRICANES AND TYPHOONS? Hurricane Barry was the last system to form in the Gulf of Mexico (Image: ACCUWEATHER) Dan Kottlowski, the lead hurricane expert


with weather forecasters AccuWeather, said the Atlantic hurricane season will be “back-loaded” this year. He said: “A big change in the pattern over the Atlantic, going from a very


lacklustre quiet weather pattern to a much more active one. “We are thinking this season will be back-loaded.” If a backlog of storms were to pummel the US over the next month, some of the


country’s most valuable commodities would be at risk. More than 45 percent of the country’s refining capacity and 51 percent of its gas processing faces the Gulf of Mexico, where the


Atlantic hurricane season is most active. African dust will lift off from the east coast and could give way to major storms (Image: NASA) Forecasters are currently monitoring one tropical


disturbance over north Florida.  The disorganised area of cloudiness and thunderstorms extends from the Gulf of Mexico and through the state.  Over the next five days the National Hurricane


Centre (NHC) has given the disturbance a 20 percent chance of becoming a tropical storm or depression.  Forecasters mentioned the system could bring heavy rain as it moves offshore towards


Georgia and the Carolina coast.  A single tropical disturbance is looming in the Atlantic Ocean (Image: NHC) Dust isn't the only factor which prevents developing storms on the US east


coast, as sea temperatures are also important.  Hurricanes require at least 26.5C (79F) in the ocean at a depth of 50 metres to form, which means they can take much longer than the


"official" July 1 date to form.  The NOAA explains: "Oceans (water) have great heat capacity than landmasses because of something called specific heat.” “Specific heat is


defined as the amount of heat for some given unit mass that is required to increase temperature by 1 degree C. “Because of its higher specific heat, it takes water longer to heat up or cool


down than dry soil (land)."