In a previous blog I talked about the African dust or S.A.L. that has been one of the factors that limited the number of hurricanes this tropical season. But killing hurricane growth is not the only effect of this sand and dust transported from the Sahara and across the Atlantic to our shores.
Research published in the Journal of Geophysical Research and Proceedings of the National Academy of Sciences by University of Minnesota scientist Paul Glaser shows that at one time the dust from the Sahara nourished plant life in the Everglades. This occurred in the distance past, some 4,600 years ago, when global winds were favorable for transport of the dust. The research adds a new dimension to traditional thought that only man had influence on increasing nutrients into the ecosystem of the Everglades by way of runoff.
The study was conducted by use of examination of core samples taken form various locations in the Everglades.
The samples showed grains of sand consistent with African dust mixed with the pollen of aquatic plants. Dating of the sample showed the age to be about 4,600 years old. However, other samples taken from a time when the climate was drier and winds had shifted did not show either the dust or the pollen.
Glasers thinking is that the colocation of the nutrient rich dust and pollen suggests a fertile Everglades created by the African dust.
Around 2800 years ago climate change likely produced a shift in the location of the Bermuda High and changed the trans Atlantic wind pattern, making it more difficult for the dust to make the ocean journey.