GLOBAL WARMING. The delta of the Amazon River is low and flat. Because it lies near the equator it is also warm and humid. It is teaming with life, most of it semi-aquatic. As the polar ice melts, and as the oceans themselves expand, sea levels will rise, backing up the Delta and flooding Amazonia.
WORLD'S LARGEST LAKE. The Delta is already the world's largest freshwater lake during the rainy season. Although covered by a canopy of jungle or filled in with pampa grassland vegetation, Amazonia is actually under standing water during the rains. As the seas move up the Delta, the water will not drain, it will merely convert to a shallow tidal basin over 2000 kilometers deep. The entire rain forest, as we know it, will not survive the briny intrusion.
THE PETRI DISH. Today, the Amazon is navigable by deepwater vessels as far as Manaus. However, the additional elevation of the highwater mark will not necessarily increase navigability because so much of the bed of the basin is flat and friable. Little or no "rock" compositions, or weak sandstones, characterize much of the basin. It is unlikely that this enormous estuary will be useful to humans or the jungle life forms presently inhabiting it. We note, of course, that the upper Amazon - near the confluences of the Beni, the Madre de Dios, and the Mamore -- has been identified as the most fecund and prolific spot on the Planet in terms of numbers of species. More kinds of life have been "found" here than anywhere else. Those freshwater "jungle" forms of life will not survive the brine, however, the warm wet incubating basin may see the emergence of new forms of life eventually launching into the Atlantic Ocean itself.
THE NEWFOUNDLAND FISHERY. As ocean rises, the "slope" of the Delta will reduce and the current will not "push" downstream with as much force. The alternating dyadic force of tide will engage and neutralize the current which now pushes the brown water thousands of miles into the Atlantic flowing North, and eventually feeding nutrients past the Carribean Sea up to the coast of Newfoundland. Since the discovery by the Bristol fisherman as a trade secret before Columbus, the Newfoundland fishery off the coast of America has been the richest saltwater fishery in the world. It is not a historical coincidence that the Whaling Industry was born in New England. However, the nutrient mass pushed into the sea from Amazonia will not only reduce, it will be "pushed" less deeply. The jungle will disappear, the brown waters clarify, and the run-off current will bow to tidal reverses. Very little nutrient will reach the fisheries of the North Atlantic.
CLARIFICATION. Over 2000 kilometers. I said "deep", referring to the vector into the interior. However this is not "deep" water -- the depth of the vast lake would be very shallow.
ReplyDeleteWe note that most of Florida and the ever-glades, and much of the lower delta of the Mississippi would also be submerged.
RIPARIAN LIFE. Most human habit extends along fresh-water channels, within what we refer to as the Fertile Crescent of river systems. What I am saying about the Amazon is geologically true about the deltas of the Yellow, Indus, Mississippi, and the Nile as well. The heavily-populated seaboard of China, and the Bangladeshi/Indus delta, all underwater with melted ice-cap sea rise.
ReplyDeleteJUNGLE CIVILIZATION. An Italian blogger using Google Maps and Google Earth spotted an image of rectangular shadows in the meander of an ancient riverbed. It was an undiscovered Roman ruin. www.quellidellabassa.org.
ReplyDeleteMany large circles, straight lines and cornerings can be discerned in the vast reaches of the Amazon delta. Particularly in the Brazilia area.
The Google images are not close enough to make out the ditch we found in Tumi Chucua. But that was really huge -- more than 500 metres.
Compare, David Grann, "The Lost City of Z" reporting for The New Yorker, 9/19/05 56, trekked the Mato Grosso and found what Colonel Harrison Fawcett (d. 1925) had at least searched and what Heckenberger is today finding -- cities.
To be done. Follow up, Kiukuros and Bakairi habitat, between the Tapajos and the Xingu tributaries--Xingu National Park. North of Cuiaba.