Rio de la Plata, Argentina and Uruguay – January 29th, 2010 – EOSnap Celebrates its 2000th Post!34.6S 58.3W
EOSnap celebrates an important milestone – its 2000th post – with this comparative look at the land surrounding the Rio de la Plata, and would like to take the opportunity to thank our readers for their patronage. The right half of the main image is a true-color MERIS reduced resolution image, while the left half is a false-color FAPAR image.
In the MERIS image, it is possible to observe the true color of the landscape as well as the tan sediments carried by the Paraná River, running parallel to the left edge, and the Uruguay River, right of the former. These two great rivers converge to create the Rio de la Plata, a funnel-shaped indentation on the southeastern coastline of South America, extending 290 kilometres (180 mi) from the rivers’ confluence to the Atlantic Ocean.
The Rio de la Plata grows from 48 kilometres (30 mi) wide where the rivers meet to 220 kilometres (137 mi) wide to the southeast where it opens on the Atlantic Ocean. It forms part of the border between Argentina and Uruguay, with the major ports and capital cities of Buenos Aires on the southern banks and Montevideo on the northern banks. A phytoplankton bloom can also be seen southeast of the rivermouth, in the lower right corner (best seen in the full version of the MERIS detail).
The FAPAR image, on the other hand, provides information regarding the vegetation index of the area by indicating the amount of photosynthetically active radiation absorbed by vegetation canopies. FAPAR, in fact, stands for Fraction of Absorbed Photosynthetically Active Radiation. Such images are generated by a Chelys processor that processes and extracts the FAPAR index from raw data in just a few seconds.
In order to interpret the false colors of the image, one must be aware that the color spectrum over land runs from red (1.0), to green, to yellow and white (0.0). The green to red areas indicate zones for which there is a good to high degree of photosynthetic activity and thus much vegetation and/or agriculture. The yellow to white areas, on the contrary, are indicative of low to no photosynthetic activity and thus little or no vegetation.
Most of the land visible here in Argentina and Uruguay shows good to high activity, particularly in the area southwest of the Paraná River. The photosynthetic activity decreases as one moves southward towards Argentine Patagonia, which is for the most part a region of slike plains covered with an enormous bed of shingle almost bare of vegetation.