[Terrapreta] Dams & wetter air (Off topic, or not off topic. That is the question.)

[Duane Pendergast]

            Michael,

 

River lovers have been campaigning against dams for decades. Almost as soon
as the greenhouse gas issue came up heavily in the nineties, the issue of
decaying trees in dams was raised as a means of discrediting hydro as a
greenhouse gas free energy source. Terra Preta enthusiasts who have come
more recently could suggest that those trees should have been harvested and
turned into charcoal for terra preta soil above the waterline before the
reservoir was flooded. 

 

By the way, I once read a paper generated in Canada - with greenhouse gas
study funding - which evaluated the generation of greenhouse gases by beaver
dams. I wondered if the researchers had a good sense of humor and were
spoofing the funders - or maybe I was taken by an April Fools joke.

 

Fresh water supply is seen by some as a bigger issue that global warming by
some, and I doubt the long established practice of controlling river flows
for irrigation and other uses is going to stop.

 

I once  looked at using nuclear energy to establish a carbon sink here in
Alberta back in 2002. The idea contemplated was to pump fresh water from the
north up to the south to supplement our meager rainfall and grow CO2
absorbing crops. I suggested at the time that the crops grown could be
turned into charcoal and buried to make a sink. The sink was estimated to be
on order of that needed to meet Canada's commitment to Kyoto. At that time I
had no knowledge of terra preta but had an inkling repeated forest fires
over many centuries probably generated significant long lasting charcoal.

 

A few details are available from my presentation at
http://www.computare.org/Support%20documents/Fora%20Input/CIE/Computare%20We
b_CNA%20CIE%20Presentation_files/frame.htm

 

See Slides 21, 22, 23 and associated notes pages.

 

Duane

 

P.S. - I think I may have posted the link above before and apologize to
those who might have read it for the repetition. Still repetition is
somewhat of a virtue here.

 

 

 

 

-----Original Message-----
From: Michael Bailes [mailto:michaelangelica at gmail.com] 
Sent: November 8, 2007 8:08 PM
To: still.thinking at computare.org
Cc: Sean K. Barry; Terrapreta
Subject: Re: [Terrapreta] Dams & wetter air (Off topic,or not off topic.
That is the question.)

 

I found a better article on the topic
http://www.rivernet.org/general/dams/greenhouse.htm

In June, the World Commission on Dams warned that the problem extended
beyond rainforest reservoirs. It told UN climate-change negotiators that
greenhouse gases bubble up from "all 30 reservoirs for which measurements
have been made." The message was clear: "There is no justification for
claiming that hydroelectricity does not contribute significantly to global
warming." 


 

 

The Commission is a blue-chip assembly of scientists, engineers and
environmentalists, and is supported by the World Bank, the world's biggest
funder of large dams.


 

 

Its findings have been corroborated by researchers from Canada, home of some
of the world's largest hydroelectric projects. Vincent St Louis, of the
University of Alberta, has made the first ever calculation of the total
contribution of the thousands of reservoirs round the world to global
warming.


 

 

In the September issue of the journal BioScience, he says that they produce
a fifth of all the man-made methane in the atmosphere. Add in their
emissions of carbon dioxide, and they make up 7 per cent of the man-made
greenhouse effect. That is a bigger impact than, for instance, aircraft
emissions. 


I doubt that they take into account countless thousands of little farm dams.
When it used to rain here you could fly over parts of Australia and see
hundreds of round, silver, glistening farm-dams that looked like shiny coins
on the ground. 

Many wetlands are drying up.Certainly here. One reason- many believe -for
methane levels dropping over the last eight years.

*   *   *   

A little study for the GW sceptics( I was one too. Read "The Weather
Makers")
 http://www.moorlandschool.co.uk/earth/greenhou.htmOn 09/11/2007, 

*   *   *   

Natural lakes help too:-

Rwanda's underwater powerhouse 


By Adam Mynott 
BBC News, Rwanda 

  <http://newsimg.bbc.co.uk/shared/img/999999.gif> 


 Boat on Lake Kivu
<http://newsimg.bbc.co.uk/media/images/42885000/jpg/_42885259_boat203.jpg> 

The calm, blue waters of Lake Kivu hold huge amounts of 'green' energy

Africa is the continent which will suffer the worst effects of climate
change. 

It also has some of the answers. 

The calm, blue waters of Lake Kivu in the west of Rwanda belie the energy
powerhouse it stores deep underwater. 

Hundreds of metres down in the inky blackness, the lake is holding enough
unexploited energy to meet Rwanda's needs for 200 years. 

Rotting vegetation which has been deposited for millions of years at the
bottom of the lake is giving off a constant regenerating supply of methane
gas. 

Some of that gas bubbles to the surface where it is carried away and
dispersed on the wind, but much of it, under massive pressure, is dissolved
in the water at the bottom of the lake, which is in places more than 600m
deep. 

http://news.bbc.co.uk/2/hi/africa/6624395.stm

*   *   *   

 

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