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Big Dams = Big Drought? Ask China
Way way back in the late 70’s early 80’s I was working for Citi. One
role I had was related to the construction of the Guri Hydroelectric dam
in Venezuela (a minor involvement). The World Bank and Inter-American
Development Bank provided a big chunk of the financing. All the big
banks were lending money to the Venezuelan government and to the local
electric company EDELCA. There were foreign contractors
from every country involved. Money was moving in every different
direction. I handled some of the FX transactions. As I result I became
familiar/interested in this mega-construction project.
On paper, this was an absolutely beautiful project. A true
perpetual energy machine was being created. The hydro dam was being
located at what looked to be a perfect location. Two maps:
For millions of years the warm water of the Caribbean produced huge
quantities of moisture that rose into the air and drifted southwest over
Venezuela’s high plains. When that wet air runs into the Andes
mountains it creates rain. Lots of it. This pattern created big rivers
like the Orinoco that bring the water back to the ocean.
This endless cycle created an ideal condition for generating hydro
power. So Guri was built. A 10,200 MW facility that flooded an area of
1,641 square miles. That’s big.
The flooded area was greater than the state of Rhode Island. The lake was 25Xs the size of the District of Columbia, 70Xs the island of Manhattan.
Your average coal plant produces only 700MW. A big nuke like the two units at Diablo Canyon produce only 2,300MW. Fukushima Daiich (4 units. Top ten globally) produced at its peak 4,700MW, less than half of the capacity at Guri.
Anything you might read about Guri will say it was a successful project. But here is my side story:
Many years later I was wearing a different hat. I was on the ‘buy-side’. Investing in (very) distressed assets. Venezuela was in the crapper at the time and EDELCA
bonds (owner of Guri) were trading at 30 cents on the dollar with 5
years of interest coupons attached for free. So I took a look. I noticed
that the MW production was substantially below what had been projected.
I asked a guy I knew at the World Bank about it:
BK: Where’s the juice at Guri?
WB:
Bad question to ask. The rainfall that historically fed the region has
changed its pattern and annual flow. There are some who think that the
enormous lake that was created changed the way the rain fell. Less
water, less electicity.
Bad question to ask. The rainfall that historically fed the region has
changed its pattern and annual flow. There are some who think that the
enormous lake that was created changed the way the rain fell. Less
water, less electicity.
BK: Incredible! Has this been proven? It would create a big stink if this were to come out.
WB: There
will be no study. The dam has been built. No one wants to hear any bad
news about this project. There are too many others like it being built
around the world. The World Bank is promoting hydro power. We don’t want to tarnish what we build.
I was struck by this conversation. Man bites nature and nature bites back.
For years I have wondered about this. There has been plenty of
anecdotal evidence that big dams might cause changes in regional weather
patterns. For example:
Recently this very important story from China has been making headlines.
ZH story (Link)
The region below the Three Gorges Dam has been in severe drought ever
since the dam was opened. This headline had me looking again at the
correlation between big dams and weather changes. Sure enough,
just last February, a collaborative effort by Tennessee Tech, Purdue, U.
Georgia, U. Colorado, and Pacific NW Labs confirmed what I had heard 20
years ago. The existence of a dam is directly associated with regional
climate change according to the study: (Link)
From the article:
"This research shows you the smoking gun"
The study marks the first time researchers have documented large dams having a clear, strong influence on the climate around artificial reservoirs, an influence markedly different from the climate around natural lakes and wetlands.
"We know a lot about how climate change affects reservoirs, but what we didn't know a lot about was what a reservoir could do to the local climate. We
just reversed our thinking by saying that a reservoir and the
activities it supports are just as important a player for climate as the
larger climate is for the reservoir. Basically, it's a two-way street."
What are the conclusion(s) here? There is no energy creation mechanism
that does not have big risks? That we are not as smart as we think we
are when we build these giants? That China has lost a breadbasket
forever?
I conclude that if you mess with nature you’ll get messed back. Hard.
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So you're saying people love doing things without cross discipline expertise. Civil engineers know some of the affects of weather and "environment" on projects. They just don't get the big weather and hydrological cycle picture.
Big dams are big business, but the complexity of the projects always exceed the size, which is why developers always employ an army of experts from diversified disciplines.
Unfortunately, management often lacks leadership. Leadership, judgement, experience, and expertise are all required to assess and properly mitigate risks. Micro climate risks and their mitigation are beyond me, but in looking at Guri the risk jumps out at me first is actually production concentration risk for the energy sector. 70+% is putting too many of Venezuela's eggs in one basket.
Since Hugo Chavez loves spouting CIA conspiracy theories, it is funny that he is actually one HAARP earthquake from having his country plunged into the dark ages, and his regime probably overthrown in the ensuing chaos.
In 2002 and 2003, a group I worked with looked at financing and finishing the Bekhme dam on the Zab river in Iraq. The project had some serious issues and challenges. However, completing the Bekhme would have increased local hydro electrical generation from 400 to 2000 MW and allowed the reservoir at the Mosul Dam on the Tigris to be systematically and substantially lowered, thereby eliminating the threat of a man-made tsunami reaching all the way to Baghdad and killing hundreds of thousands in the event of the well established risk of a dam failure.
One of the senior guys on the Iraq project had been offered an extremely prestigious executive position on the Three Gorges project a decade earlier, and had turned it down because of a number of concerns about project design. Dams are extremely capital intensive to construct. If done right, they can be extremely beneficial to the local economy and the negative impacts to the environment more than offset by benefits. However, when a project is not done right the first time, the costs of correcting the situation later can be astronomical- financially, environmentally, and in terms of human life.
Dams - damned if you do, damned if you don't, so do the dam(n) thing right the first time.
Fascinating post Bruce.
An additional factor comes to mind:
Land clearance is known to effect rainfall patterns:
http://www.nasa.gov/centers/goddard/news/topstory/2004/0603amazondry.html
Weaker anecdotal evidence also suggests an influence:
http://www.farmradio.org/english/radio-scripts/54-1script_en.asp
The construction of a large dam necessarily involves a great deal of land clearance, not just in the area of the dam, but also in the catchment for the dam. Presence of vegetation in the catchment prevents inflows to the dam, so clearance is required. Empirical evidence demonstrates that land clearance alters local rainfall patterns.
Then there is the influence of a large body of water stored inland (storing heat and evaporating) that should, in fact, be out to sea. The study you linked to seems to confirm there is an effect here.
My semi-informed guess is that natural systems buffer weather in the lower troposphere by regulating the hydrological cycle and by emitting gaseous metabolic products (ethylene, etc), some of which may effect rainfall. When considering water flows, it makes sense that vegetation serves to dampen extremes of release as rainfall that must proceed through a pathway of root absorption followed by leaf transpiration returns to the atmosphere by a different course (and timing) than water simply evaporating from an open water surface or exposed soil. That change probably translates into altered rainfall patterns.
Anyway, just speculation. Be good if someone could actually dig up scientific studies.
Great Post Bruce, as always, thanks.
Interestingly I do have a similar experience.
15 yrs ago, i went to a ski resort in Eastern Turkey-Erzurum, Palandoken mountain with my friends. The resort area is very famous with its longest ski season, heavy snow, cold weather. Time was end of march, where there is supposed to be at least 1m (40") of snow, but there was a thin layer of snow and it melted quickly, then lifts were closed and we couldn't ski anymore. During a conversation with a Taxi driver, he told us that after they built the Ataturk dam( which is close ), the weather in Erzurum area had changed dramatically, No more few meters of snow. I guess it happens in all dams.
Great deduction.
Wind is very fragile but very powerful.
No one considers that anything that alters the natural terrain also alters the way wind travels over it. Even buildings have an effect. Many buildings have a larger effect and a small effect over a long period of time has a cumulative effect. We all want to think that solar panels and wind farms are "zero impact", but no matter how negligible this cannot be the case.
Even farther out there on the fringe is "Air Conditioning". Nothing exists in a vacuum. When you artificially cool and simultaneously suck the moisture out of the air then we really get into the discussion about "the butterfly effect" of a 100 trillion wings.
IF you want to see how hydrodams destroy the environment you don't have to look any farther than the Pacific Northwest. There hasn't been a "natural" born Salmon in twenty three years because of the 14 dams end to end of the Frasier and Snake river, the fish tend to get chewed up or die of exhaustion. 90% of all the pink sockeye Salmon every eaten today is farm raised and is more than likely one of the Chimeras mixed with "something" else (pig, horse, monkey, who knows).
Boring!
This is going to be one long, slow trendless summer.
At least put up a few of your favorite porn links.
For something most of you have never seen before try zoo tube for cross species sex. Now I truly have seen everything.
Hey Bruce, another good article.
Check this out: Tropical Atlantic Water Vapor Loop
http://www.ssd.noaa.gov/goes/east/tatl/flash-wv.html
As an east coast hurricane watcher, this is very strange.
As someone who is unfamiliar with how things would look normally, could you please explain what is [very strange] about what I am seeing in the link?
thank you :)
At this time of the year, the equatorial trough is shifting north. This is a region where little horizontal airflow should be occurring (hence sailors call it the doldrums). Air flow is instead vertical, being the closest point of the earth's surface to the sun and hence the warmest. Moisture carried up from the equator spreads north and south.
So what's a bit odd about this picture is the rapid motion of water vapour to the east at high speed (I estimate about 200km/hr just by eye). The direction isn't strange, but the speed is. Jet streams typically operate above 30 degrees of latitude. That's where you'd normally expect to see rapid lateral flows.
Still, it's just one observation, which doesn't indicate much in isolation. Northern hemisphere Rossby waves do occasionally "drop" down to lower latitude, bringing high lateral airflows with them. If you look at a 7 day animation of the sub-tropical jet stream over north america, that appears to be what happened here:
http://squall.sfsu.edu/scripts/namjetstream_modelsml.html
Note the way the jet dampens, drops and reforms, sending a residual down towards the SE of the USA. I think that's probably what was responsible for this squeeze of moisture east.
Thank you.
The movement along the eastern seaboard is moving backwards. I can only wonder what this means for the Gulf Stream and the Atlantic Conveyor. If it keeps up, the UK could be frozen over in thirty years.
:?
Thank you ma'am
Well, I don't know, actually. It was just a supposition. Like you, I was wating for the poster to return and explain what he/she meant.
I do know that, normally, the Gulf Stream carries water vapor north to Great Britain and now there is a mass moving south along the US coast. How unusual is it? Is it really that "strange"? I don't know.
It would be helpful to know because I am in Texas and we are prone to getting severe Gulf weather.
Careful with your terms, the Gulf Stream is an ocean current, not an atmospheric current. It carries water, not water vapour. I think you meant to say "jet stream".
Atmospheric events don't effect ocean currents much (if at all), it's the other way around. So if atmospheric observations are looking weird, it might be indicative of something odd going on in the oceans, and THAT, as you suggest, is trouble.
Here's a nice link for you, I know you like links :-p
http://www.sciencedaily.com/releases/2008/03/080320181838.htm
Nice to see you again.
No, I meant Gulf Stream, not jet stream and, to tell the truth, I don't much care for links. :) But I'll read yours because I know they have some substance...
Well, have a look at the water vapor pattern in the Atlantic basin. Why is that storm moving down the coast instead of north, as it usually does?
That was the ony thing I saw "strange" but maybe you can see what the previous poster was talking about.
:D
P.S. The article seems to contradict what you said about ocean v. atmospheric currents. But I guess what I meant was that storms tend to follow along the Gulf Stream toward the UK.
Hello Orly. You have noticed the same things I have. I live on the NC coast and yesterday I noticed that the clouds were moving in from the north east...which is unusual unless there is a low pressure system off the coast. I checked out the water vapor and was very confused to see a storm moving from North to South and spinning in a strange way. I've never seen this happen before. It's now showing up on the National Hurricane Center as a 30% chance of tropical cyclone formation (place cursor over orange circle). Weird.
http://www.nhc.noaa.gov/
Good post. Makes me wonder about wind power. Seems to me that conservation of energy would indicate that if you use windmills to extract power from the environment, then that power is no longer in the environment to do whatever it was doing previously. I wonder what effect that will have over time. Same with proposals for capturing tidal energy. To use Bruce's terminology, it will be interesting to see how nature will mess us back hard in these areas.
great post Bruce. always thought it would be the three gorges that would stop China dead in its tracks in its march towards Empire. what they destroyed in building the dam was such a wonderful harmony between man & nature. Mother wasn't pleased that's for sure.
Very interesting. great research, thanks. More subtle than the ethanol and food price increase connection.
PS. Bruce, where did you get that cool tree?
Google search: "Don't fuck with nature"
It comes up in the images for this phrase.
Sinnnnngggggginnnnnggg in the rain, just sing-ing in the rain, what a glorious feeling I'm happy again......
Die you commie brownshirts...... dat dat dat dat dat......
Very interesting. So cities and reservoirs can alter weather patterns.
You might be interested in reading John McPhee's "The Control of Nature"...especially in light of the recent Mississippi River flooding.
http://www.johnmcphee.com/controlofnature.htm
Yow. When have the "best laid plans of mice and men" ever worked?
Recently I read that the earth's rotational axis shifted slightly the filling of the Yangtze Dam reservior. Apparently the laws of physics had to cope with the presence of a new super massive object where previously only atmosphere was present.
It seems this in turn would cause additional climate changes. God help us.
Thanks Bruce. A large body of water is basically a heat sink, which moderates the temp around it. I live close to one such natural lake. The winters are more moderate and summers cooler close to the lake than than outlying areas.
Another great post BK!