segunda-feira, 12 de setembro de 2011

More fresh water

Fresh water is a major issue that Humanity is facing. We use a lot of fresh water, most of the times, too much. And it is important that we preserve this valuable resource. But when very good news about fresh water arise, they are normally not valued by the alarmists.

This is what has happened in Brazil. Two major fresh water discoveries were made, but little has been said about it. The Verde blog brought it to my attention. Maybe, Al Gore will mention it from Rio de Janeiro, in his Climate Reality stunt?

The first discovery refers to an underground "river" that flows beneath the Amazons River, named the Hamza River. A visual representation can be seen on the image on the left, obtained here. The Hamza is a very slow flowing river, at around 10 to 100 metres/year, and is 6000 kilometres long. The flow rate is much lower that that of the Amazon, but it is much wider, at 400 kilometres. The discovery is the work of Elizabeth Pimentel, a PhD student supervised by Valiya Hamza, for whom the river was named. The good news were presented at the 12th International Congress of the Brazilian Geophysical Society, last Aug 17th.

The second discovery is related to the first, but is older. Milton Matta, and his team at LARHIMA (Laboratory of Water Resources and Environment), announced last year the discovery of the size of the Alter do Chão aquifer, believed to be bigger than the Guarani Aquifer, in terms of volume. Despite being smaller in size than the Guarani (both pictured left), the Alter do Chão aquifer is believed to have 86000 km3 of water, against Guarani's 45000 km3. This is due to a bigger thickness in Alter do Chão, which is also nearer the surface. There is enough water in this aquifer to fill Lake Superior, the third-largest freshwater lake by volume, seven times!