wearing the orange sky of the Caribbean Sea during the hot summer are caused by thin layers of dust from the African continent. High temperatures, low humidity and cloud cover of fog outside the season are indicative of the existence of fine dust particles (smaller than a hundred microns) carried over from the African continent into the Caribbean Sea.
The Sahara desert can be considered an "incubator" sandstorms that rise into the atmosphere large amounts of dust at altitudes of 5 to 7 km, forming a mass of hot air and humidity of just 3% which covers an area of \u200b\u200babout 800 km, affecting areas like the Islands Canary Islands, Spain, Portugal, Britain and the Caribbean islands.
Sandstorms are a product of the clash between the hot desert air with the cooler air of the Sahel region (south of the Sahara). The trade winds are responsible for this mass is transported across the Atlantic to reach the Caribbean. Although during the year are usually formed several dust storms in the African region, the frequency of fog Saharan increases between May and August, thus having the highest incidence peaks between June and July.
The Saharan dust is the main suspect in the high incidence of respiratory illness during the summer months. He is also credited to be responsible for the so called red tides (large concentrations of red algae due to increased salinity of the sea). However, not all effects of Saharan dust are negative.
The presence of dust reduces the size of raindrops and inhibits the formation of clouds of large vertical forming a dry climate. There has also been a reduction in sea surface temperatures due a cloud of dust that blocked sunlight before it hit the ocean. Research suggests such dust outbreaks may inhibit hurricane formation.
NASA satellites have provided evidence that the cooling effect of dust was responsible for one third of the drop in sea surface temperatures in the North Atlantic between June 2005 and 2006, possibly contributing to the difference in hurricane activity between the two stations. The heat stored in warm ocean surfaces is known that fuels hurricanes, creating stronger storms and more frequent.
Amato Evan, a researcher at the Cooperative Institute Meteorological Satellite Studies, University of Wisconsin-Madison, studied more than 25 years of data gathered by satellites from 1981 to 2006, and noticed the correlation. Found that during periods of intense hurricane activity, dust was relatively scarce in the atmosphere. On the other hand, in the years when dust storms rose up stronger, fewer hurricanes swept across the Atlantic.
If scientists conclusively prove that dust helps mitigate the hurricane, those responsible for weather forecasts could one day begin to track atmospheric dust and take it into account for the first time in their predictions.
scientists are increasingly devoting attention to the environmental impact of dust, having found that in some years, many millions of tons of sand rise from the Sahara Desert and float across the Atlantic Ocean, sometimes in just five days.
The new study's authors argue that the dusty layers of air probably help reduce hurricane activity in training because they need heat and moisture to feed. This effect could also mean that these dust storms have the potential to change the direction of a hurricane.
While the work of the University of Wisconsin-Madison that dust does not confirm that directly influence hurricanes, it does provide important evidence that both phenomena are related in some way. "We do not know if the dust affects the hurricanes directly, or whether both (dust and hurricanes) respond to the same global atmospheric changes of the tropical Atlantic."
remains then open the gap between those who believe that the Saharan dust is the main ingredient in the formation of hurricanes, because the genesis of these often happens in that region, and those who have recently discovered that this dense layer Traveling could be the shield against hurricanes.
MAP SATELLITE ON DENSITY OF DUST SAHARA:
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cimss.ssec.wisc.edu maps
cimss.ssec.wisc.edu maps
RELATED VIDEOS SAHARA DESERT:
HURRICANE RELATED VIDEOS
SOURCES:
CIMS.SSEC.WISC.EDU
METEORED.COM
GEOSALUD.COM
SOLOCIENCIA.COM
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