Daily Archives: September 27, 2013

Glaciation in Bolivia

Bernardo Ellefsen writes in Los Tiempos:

Glaciation in Bolivia

2013-09-26 10.32.41 amIn a previous article I stated briefly how glacial eras will behave and promised that I would give local examples. Glacial eras would be produced by the increase in precipitation, and areas in snow by the formation of layers of snow compacted into ice that would melt in summer, which would cool the entire geographical environment.

If it rains very much for days in a row in Cochabamba, it will likely snow in the mountains. In an ice age the rains should be quite intense; there will be layers of snow mountain range that will not melt. It was just by the action of glaciers that formed numerous gaps that exist in the plateau on the northern slope of the mountain ranges of Cocapata and Cochabamba, now given to call the Tunari.

In the Highlands, rainfall increased brought up the level of Lakes. As Lake Titicaca flows on the Desaguadero, it did not raise much, but still the Cattail halted its relief and the lake spread to the angostura de Callapa, Pacajes province. The largest lake of the past has been called Ballivian. In the South, a vast lake, which has been called Minchin was formed. When Lake Minchin dried out, left two large eyes of salt in its Fund, which are the current salt flats of Uyuni and Coipasa.

Lake Poopó is geologically of recent formation. It was formed because the sediments from the delta of the river Marquez have prevented the waters that make up the Poopó, to continue its course towards the Lake and salar de Coipasa. Federico Ahlfeld, geologist made an easy finding, to determine that the Lacajawira River, which goes from the delta of river Marquez to the Coipasa Lake, is only formed with waters of the river Marquez and not the Poopo Lake: tested the waters. The Lacajawira River is freshwater, while Poopo has salt water, for not having a drain. It is like a pot, if it is not drained, it becomes salty.

To this, it must be noted something interesting that has been clarified in recent decades. After the last glacial era, it was ensued an intensely dry period in the Sahara, with contraction of African tropical forests. That period was synchronous with one of intense drought in the Central Andes, with decrease in the level of the waters of Lake Titicaca that were not drained, they went on to form two comparatively small lakes.

Then back to rain substantially, in a period that has been called the Sahara “sub-pluvial Neolithic”, approximately the 7550 or 7000 to 3500 or 3000 before the common era in use. Then the region of the Sahara was once again a desert due to lack of rain, process which now intensifies noticeably. With that we have that we are currently in a period of a relatively dry climate, although much less that for 5 or 7 millennia. Is expected, but not with certainty, that the global warming produces an increase of evaporation from the seas and as a result an increase in the average rainfall. For the Bolivian Andean region that would mean more rain, more snow, and growth of the surfaces of the Altiplano Lakes, with the improvement of the vegetation.

The author is a writer