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Yet, after Beryl struck the eastern Yucatán as a category 2 storm on July 5 and the Texas Gulf Coast as a category 1 storm on July 8 (see Saffir-Simpson hurricane scale), cyclone development slowed dramatically, with few storms threatening land and no named storms occurring between August 13 and September 3 (the beginning of peak hurricane season). According to some sources, it was the quietest such stretch since 1968.
Scientists attributed this lull to two factors. The first was a wetter-than-average West African monsoon, which sapped energy from atmospheric disturbances called easterly waves, which occur off the coast of Africa and from which most hurricanes develop. The second factor was dust plumes kicked up by the Sahara. These dust storms take place every three to five days from spring to early fall, and they travel westward (pictured below) across the tropical Atlantic as far as the Caribbean Sea. By September the dust had largely abated, but for much of the summer, dust aloft appeared to be thick enough and widespread enough to block much of the sunlight (and thus heat energy) needed for hurricanes to get organized.
Still, Helene’s origin story is also unusual. Instead of evolving from a disturbance off the African coast, Helene arose out of a low-pressure system near the Yucatán Peninsula. As it moved north over warm water into the Gulf of Mexico, the system rapidly intensified from a tropical depression to category 1 hurricane in only 30 hours.
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Despite its ties to the Internet, English-language fan fiction isn’t anything new; it traces back to the 18th century.
A groundbreaking musician and composer, her early use of the synthesizer blazed a trail in electronic music.
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This sweetener is used in a great variety of food and beverage products. But what is it and how is it made?
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