What a Difference a Day Makes!
Posted: Fri Oct 03, 2014 8:40 am
On island for this lowest of the low season, and for the most part, the weather has been excellent. No storms in an exceptionally quiet Atlantic hurricane season, and only one day in two weeks that was a rain-out (and even that began with on and off sun). As recently as yesterday, the visibility was excellent; on Thursday, Vieques and Culebra were easily seen from Gifft Hill (45 miles), and on Wednesday I could even make out the southern slope of El Yunque on Puerto Rico - 65 miles away!
We awoke today to an entirely different panorama, as I had expected from a look at the University of Athens dust forecast. Here is a view from the deck at Coconuts on Thursday; my lens isn't wide angle enough to capture the whole panorama in one image, so French Cap to Great St. James isn't visible, or Great Cruz Bay, but the scene from St. Thomas to Great Hans Lollik is really nice and crisp: Now here is the same view, taken this morning (Friday). The dust plume rolled in overnight. I had noticed during the evening that the stars were all pretty faint. And here are the respective dust forecasts from the great site at the University of Athens (http://forecast.uoa.gr/dustindx.php): By the end of October, dust such as this will have mostly tapered off. From April to now, however, it is a bit of a dice roll as to the clarity on any given day. Fortunately, dust plumes can depart as quickly as they arrive.
Edit: While it has been known for some time that most of the soil in the Amazonian rainforest was transported from Africa as Sahara dust, and that the dust plays a role in discouraging hurricane formation, Sahara dust has recently won a new kudo. It appears, from recent research at the University of Miami, that the Great Bahama Bank and the Bahama islands came about due to fertilization of the sea water with iron-rich Sahara dust, which led to massive cyanobacteria blooms, which in turn produced the carbonate that makes up the bank and islands. Cool!
http://rsmas.miami.edu/news-events/pres ... mas-great/
All the best,
Kevin
We awoke today to an entirely different panorama, as I had expected from a look at the University of Athens dust forecast. Here is a view from the deck at Coconuts on Thursday; my lens isn't wide angle enough to capture the whole panorama in one image, so French Cap to Great St. James isn't visible, or Great Cruz Bay, but the scene from St. Thomas to Great Hans Lollik is really nice and crisp: Now here is the same view, taken this morning (Friday). The dust plume rolled in overnight. I had noticed during the evening that the stars were all pretty faint. And here are the respective dust forecasts from the great site at the University of Athens (http://forecast.uoa.gr/dustindx.php): By the end of October, dust such as this will have mostly tapered off. From April to now, however, it is a bit of a dice roll as to the clarity on any given day. Fortunately, dust plumes can depart as quickly as they arrive.
Edit: While it has been known for some time that most of the soil in the Amazonian rainforest was transported from Africa as Sahara dust, and that the dust plays a role in discouraging hurricane formation, Sahara dust has recently won a new kudo. It appears, from recent research at the University of Miami, that the Great Bahama Bank and the Bahama islands came about due to fertilization of the sea water with iron-rich Sahara dust, which led to massive cyanobacteria blooms, which in turn produced the carbonate that makes up the bank and islands. Cool!
http://rsmas.miami.edu/news-events/pres ... mas-great/
All the best,
Kevin