This latest video documentary from the USGS discusses the rapid decline in the health of Coral reefs and reports on the latest findings. In searching for a large scale process that could be contributing to the spread of coral disease they discuss the hundreds of millions of tons of dust carried from the arid desserts of Africa and weather microbes, contaminants or pollutants are being delivered with the dust. Obviously mankind plays a role in this decline as well with our global impact on marine life and water quality. Well worth the short 10 minutes it takes to hear about the latest findings.

FROM THE VIDEO TRANSCRIPT
Thus far, scientists have identified the causes of six coral diseases: Sea fan disease (or Gorgonian Aspergillosis), Black Band Disease, White Plague, White Pox, bacterial-induced bleaching, and pink-spot disease.

Why are the diseases on the increase? Why are they so wide spread? Why are reefs worldwide in decline? What large-scale processes could be at work?

Hundreds of millions of tons of dust are carried each year from the Sahara and Sahel regions of Africa to the Caribbean, the eastern United States, and beyond. At times, these dust air masses cover the tropical Atlantic and the entire Caribbean Sea. Is this large scale system having an effect on coral reefs throughout the Caribbean?

African desert locusts are known to be periodically carried along with the dust and arrive alive on several Caribbean islands. If a two-inch locust can survive the trip across the Atlantic, can smaller organisms such as disease causing microbes survive as well? Scientists at the U.S. Geological Survey are trying to determine whether downwind ecosystems are being harmed by nutrients, microbes, or chemical contaminants carried with African dust.

Source: http://gallery.usgs.gov/videos/223

See more images of the reefs and satellite images of dust storms from USGS