Claim: Dams are major driver of global environmental change

From the UNIVERSITY OF WATERLOO

Lake Orovile Dam

Water reservoirs created by damming rivers could have significant impacts on the world’s carbon cycle and climate system that aren’t being accounted for, a new study concludes.

The study, conducted by researchers at the University of Waterloo and the Université libre de Bruxelles, appears in Nature Communications. It found that man-made dam reservoirs trap nearly one-fifth of the organic carbon moving from land to ocean via the world’s rivers.

While they can act as a significant source or sink for carbon dioxide, reservoirs are poorly represented in current climate change models.

“Dams don’t just have local environmental impacts. It’s clear they play a key role in the global carbon cycle and therefore the Earth’s climate,” said Philippe Van Cappellen, a Canada Excellence Research Chair in Ecohydrology at Waterloo and the study’s co-author. “For more accurate climate predictions, we need to better understand the impact of reservoirs.”

There are currently in excess of 70,000 large dams worldwide. With the continuing construction of new dams, more than 90 per cent of the world’s rivers will be fragmented by at least one dam within the next 15 years.

The study’s researchers used a novel method to determine what happens to organic carbon traveling down rivers and were able to capture the impact of more than 70 per cent of the world’s man-made reservoirs by volume. Their model links known physical parameters such as water flow and reservoir size with processes that determine the fate of organic carbon in impounded rivers.

“With the model used in this study, we can better quantify and predict how dams affect carbon exchanges on a global scale,” said Van Cappellen, a professor in Waterloo’s Department of Earth and Environmental Sciences.

In similar recent studies, the group of researchers also found that ongoing dam construction impedes the transport of nutrients such as phosphorus, nitrogen and silicon through river networks. The changes in nutrient flow have global impacts on the quality of water delivered to wetlands, lakes, floodplains and coastal marine areas downstream.

“We’re essentially increasing the number of artificial lakes every time we build a dam,” said Taylor Maavara, lead author and a PhD student at Waterloo. “This changes the flow of water and the materials it carries, including nutrients and carbon.”

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Gerry, Engliand
May 17, 2017 11:40 am

Well since carbon doesn’t play a key role in Earth’s climate we have another pointless study.
Anyone else have an issue with the statement that over 90% of the World’s rivers will have a dam in 15 years time? That seems completely way over the top to me.

wws
Reply to  Gerry, Engliand
May 17, 2017 12:59 pm

File this study under “When we change the world, the world changes.”
Wow, what a concept!
In relation to the surface area of the oceans, all the lakes we have made are a rounding area, so there’s not going to be a significant global change in water vapor in the atmosphere due to evaporation. However, there could by large local changes, probably allowing many things to grow and thrive in areas where they otherwise would not. Imagine that.

Bryan A
Reply to  wws
May 17, 2017 2:20 pm

What did the Fish say when it swam into the Concrete Wall??
DAM

george e. smith
Reply to  wws
May 20, 2017 10:20 pm

The heck they say ! you build a dam and something changes.
I never would have guessed that. Do they really think building Boulder Dam actually changed anything ?
What about Grand Coulee Dam; did building that change anything at all other than just leave a whole lot of concrete laying around, that wasn’t there before.
I wonder if building the City of New York changed anything.
I think I could use some grant money to see if building anything, changes anything.
g

Mike
Reply to  wws
May 21, 2017 5:38 pm

right on WWS!
Also there’s a bunch of dry land below sea level, the Qatara depression in Egypt/Libya, The Afar depression in Ethiopia/Eritrea, Death valley California, the Dead sea, Lake Clare Australia to name a few. Filling them with sea water would: a). ‘Fight’ sea level rise. b). Cool the planet through increased evaporation c). Increase humidity / rainfall in desert areas. and d). Offer Investment opportunity for an international chain of BSL* Yacht Clubs. Any Punters out there?
* Below Sea Level.

Reply to  Mike
May 23, 2017 9:31 am

Imperial Valley is also BSL

Ben of Houston
Reply to  Gerry, Engliand
May 17, 2017 1:25 pm

If they are meaning river systems from source all the way to the sea, that seems right. Almost every river has a dam somewhere along its length. While you can’t dam the whole Amazon or Mississippi, some of the tributaries are dammed.

Richard Bell
Reply to  Ben of Houston
May 18, 2017 12:13 pm

While you ***could*** build a dam across the mouth of the Amazon river. By ‘***could***’, I mean that it is possible to put in enough temporary diversion pipelines, the pumps to move the water, the prime movers to run the pumps, and get the water around the construction site, but if you have the power to drive the pumps, what do you need the dam for?
While the Chinese Communist Party would bankroll this in a heartbeat to make it look like there was real growth in their economy [overproduction in almost every category, so they need the appearance of high demand], the reason that there is no dam at the mouth of the Amazon is that there is no reason for a dam at the mouth of the Amazon.
Damming the Mississippi would so complicate transcontinental movement in the US, that it is a non-starter, even if The State could displace everyone on the flood plain with zero compensation.

Reply to  Gerry, Engliand
May 17, 2017 2:43 pm

Possibly 89% of the world’s rivers already have at least one dam?
I was really surprised that it wasn’t 97%.

george e. smith
Reply to  Retired_Engineer_Jim
May 20, 2017 10:23 pm

Well if you build the All Amazon Dam way upstream, you could get by with a smaller dam. Seems pretty silly to build a dam across the mouth. Just build it right up in the head waters where its only a few yards across.
g

Roger Dewhurst
Reply to  Gerry, Engliand
May 17, 2017 3:24 pm

That could be true if your definition of a river is a stream with a dam in it!

JohninRedding
Reply to  Gerry, Engliand
May 17, 2017 5:50 pm

My thoughts exactly. You have to assume (better yet, prove) that carbon is a major player in earth’s climate. Based on the last 20 years of no temperature increase that puts in question the significance of carbon impact on earth’s climate.

crackers345
Reply to  Gerry, Engliand
May 18, 2017 12:26 am

of course carbon plays a key role
in earth’s climate.
denying that is denying
basic physics.

Reply to  crackers345
May 18, 2017 7:47 am

High school physics. When you dive deeper, it gets more complicated.

ferdberple
Reply to  crackers345
May 18, 2017 10:24 am

without carbon dioxide there would be no life. life modifies the local climate to maintain life. those life forms that could not went extinct long ago. something the climate models have ignored.

higley7
Reply to  Gerry, Engliand
May 18, 2017 6:24 am

This study is also pointless because it is not science, but uses fatally flawed models and cobbles onto them. Possibly good science layered onto bad or junk science results in bad science every time. A real waste of time and money.

Latitude
May 17, 2017 11:41 am

The study’s researchers used a novel method….
pop…….the sound of my head exploding

Bryan A
Reply to  Latitude
May 17, 2017 12:29 pm

Perhaps they read it in a Novel

Reply to  Bryan A
May 17, 2017 3:01 pm

Aren’t most novels fiction?

Mark from the Midwest
Reply to  Latitude
May 17, 2017 1:28 pm

Was a typo, supposed to be NAVEL method, as in gaze at their navel

Not Chicken Little
Reply to  Latitude
May 17, 2017 2:10 pm

So they didn’t really determine what was happening by experiment and observation, but used a computer model…so yes, it was a novel method, and the novel is a work of fiction…

Jay Turberville
Reply to  Not Chicken Little
May 17, 2017 6:07 pm

Everybody knows that you need at least a 528 gallon aquarium to properly do this kind of study.

JEM
Reply to  Latitude
May 17, 2017 3:21 pm

I thought the rule for attorneys was that when you see the word ‘novel’ in something coming from a judge, you’re in trouble.

Biggg
Reply to  JEM
May 18, 2017 5:51 am

Come on everyone knows it is 528.6 gallons for a proper study.

Ian Magness
May 17, 2017 11:42 am

Dams trap water and thus anything in that water.
Shock!

Coeur de Lion
May 17, 2017 11:44 am

Well I never!

Nozza
May 17, 2017 11:46 am

Hahaha! What a useless piece of research. 90% my “arse”!

May 17, 2017 11:47 am

I guess Dams are now Fossil fuels. And of course Nuclear (newclar for Jimmah Cawtaw fans) is verbotten. Which leaves just wind and sun.
Yea, that will run the world.

Tim
Reply to  philjourdan
May 17, 2017 12:07 pm

You left the ‘i’ out of ruin.

Bryan A
Reply to  philjourdan
May 17, 2017 12:30 pm

Thought it was Nucular

Tom Halla
Reply to  Bryan A
May 17, 2017 1:18 pm

Nucular was George W. Bush.

Reply to  Tom Halla
May 18, 2017 7:30 am

Before your time. Cawtaw did it first.

Tom Halla
Reply to  philjourdan
May 18, 2017 8:46 am

The difference between a Georgia and a Texas accent. I do remember Jimmy boy

Reply to  Bryan A
May 17, 2017 1:22 pm

You are probably correct. I never could spell southern.

Bryan A
Reply to  Bryan A
May 17, 2017 2:21 pm

You’re right Tom
Nucular was Bush…and Bush II

Joe Shaw
Reply to  Bryan A
May 17, 2017 4:01 pm

And Jimmy Carter who was a actually trained Naval Nucular Engineer.

RACookPE1978
Editor
Reply to  Joe Shaw
May 17, 2017 5:08 pm

Well, not so much. He was more highly qualified asa USN officer than I thought, but most definitely NOT as a nuclear engineer, nor as a nuclear power plant operator/engineer/designer.
This from a letter relating the details:

Dear Mr. Fialka ..
One myth correction, however. President Carter was a submarine officer, but he was not a nuclear engineer.
He graduated from the US Naval Academy in June 1946 (he entered in 1943 with the class of 1947, but his class was in a war-driven accelerated 3 year program) with an undesignated bachelor of science degree. Even if the Naval Academy had offered a majors program for his class, it is unlikely that it would have included Nuclear Engineering as a option – after all, the Manhattan Project was a dark secret for most of his time at Annapolis.
After graduation, Jimmy Carter served as a surface warfare officer for a two years and then volunteered for the submarine force. He served in a variety of billets, including engineer officer of diesel submarines and qualified to command submarines.
In November 1952, he began a three month temporary duty assignment at the Naval Reactor branch. He started nuclear power school (a six month course of study that leads to operator training) in March, 1953. In July 1953, his father passed away and he resigned his commission to run the family peanut farm. He was discharged from active duty on 9 October, 1953. According to an old friend of mine who served as Rickover’s personnel officer at Naval Reactors, LT Carter did not complete nuclear power school because of the need to take care of business at home.
The prototype for the USS Nautilus was completed in Idaho in May 1953, so LT Carter might have had some opportunity to see it in action before leaving the Navy. However, the USS Nautilus did not go to sea until January 17, 1955, so there is no possibility that he ever qualified to stand watch on a nuclear powered submarine.
He never experienced the incredible gift of being able to operate a power plant that was so clean that it could run inside a sealed submarine, so reliable that it could power that submarine even deep under the Arctic ice, and so energy dense that the submarine could operate for years without new fuel.
When I think about the 1976 campaign and the importance of the energy issue at that time, I cannot help but wonder why Jimmy Carter’s promoters made such a big deal about his nuclear expertise. My wonder turns to cynicism when I think about the policies that his administration imposed and the damage that they did to the growth of the industry just at a time when we most needed a vibrant new energy industry player.
Best regards,
Rod Adams
Editor, Atomic Insights
http://www.atomicinsights.com

https://atomicinsights.com/picking-on-the-jimmy-carter-myth/
And some more details on Carter’s “enhanced resume” as a “nuclear engineer” …
https://seekerblog.com/2009/08/27/resume-inflation-how-a-peanut-farmer-became-a-nuclear-engineer/

It is embarrassing how much rubbish we acquire that accumulates the varnish of truth. Until I read Rod Adams today I carried around the belief that Pres. Jimmy Carter was a Navy-trained nuclear engineer and a former nuclear officer. He was neither. What is dangerous about this sort of resume-buffing and credentials-inflation is that Carter was able to destroy the entire US nuclear industry – in part because people thought he “must know about that nuclear stuff”.
If Lovins’s article did influence the 1976 election, it helped to elevate another man whose resume has received some inflation. That inflation may have been done by political handlers, but there is something slightly questionable about allowing someone to create a life story that is simply not true. I would guess that somewhere north of 90% of the people who know who Jimmy Carter is would tell you that he was a nuclear submarine officer. Some who have watched a PBS show called The Presidents: Jimmy Carter might even say that he served as the engineer officer of the USS Seawolf, the second US nuclear submarine. If the person being questioned is a real buff who has taken a Pentagon tour and seen the wall displays that celebrate the presidents who have served as Naval Officers, he might even tell you that President Carter received a Master of Science in Nuclear Engineering from Union College in Schenectady, New York.
The problem with each of those descriptions of Jimmy Carter’s nuclear experience is that they are wrong, something one can figure out with a calendar that has accurate historical dates.
Jimmy Carter could not have been a nuclear engineer based on his college degree program; he graduated from the US Naval Academy in 1946 with a general Bachelor of Science, before that school offered any designated degree programs.
According to the Naval Historical Center, LT Carter was honorably discharged from the US Navy on October 8, 1953 so that he could return home to care for the family farm. He had only started his nuclear power training on March 1, 1953. The training, in those very early days of the Navy’s nuclear program before the start up of Navy training courses, was conducted at civilian colleges, and Union College was one of the locations. However, it was definitely not a place where one could earn a master’s degree in nuclear engineering in just 7 months. That is especially true when you understand a bit about the Navy and realize that LT Carter probably did not do too much studying after he found out that his father had passed away in July 1953. (Leaving the Navy is not as simple as walking out the door.)
The PBS documentary is quite misleading with regard to Carter’s service, since it states that he served as the engineer of the USS Seawolf, the second US nuclear submarine. That statement is made with a backdrop of the USS Seawolf in operation. Unfortunately, that would have been impossible. The keel laying for the Seawolf took place in September 1953. That means that the construction process started just one month before Carter left the Navy to return to Plains. His service record indicates that he was assigned to the crew that would eventually man the USS Seawolf, but that is certainly not the same as serving as the engineering officer of an operating submarine in terms of the opportunity to absorb nuclear technical knowledge.
It is possible, but unlikely that LT Carter ever watched a nuclear plant in operation. S1W, the prototype for the USS Nautilus, the first nuclear propulsion plant that the Navy constructed, started operating in March 1953, but it would be unusual to have nuclear power school students visiting the prototype during their first six months of training. After Carter left the Navy, there is no evidence of his having had any nuclear related employment; he was too busy growing and selling peanuts and serving as a Georgia state senator and later as Georgia’s governor.
President Carter’s exaggeration of his nuclear experience had an impact on the way that the public viewed his cautious statements about nuclear energy and the way that political leaders accepted his efforts to restrict its growth. When he issued an energy policy that emphasized the use of coal as a way to reduce American dependence on foreign oil, there were many who expressed the view that he must know what he is doing, after all, he was a “nuclear engineer”

Michael darby
Reply to  Bryan A
May 17, 2017 5:14 pm

One good thing about Carter, he didn’t have any bone spurs in his feet.

Reply to  Michael darby
May 18, 2017 12:02 pm

Or grey cells in the head.

Darrin
Reply to  Bryan A
May 18, 2017 10:26 am

FYI concerning Jimmy Carter and the Nautilus. In Idaho there’s an area designated as INEL where testing is done on various reactor designs. One of test areas held a working reactor/engine room of what was to be built into the Nautilus. It was built to be in a pool so they could test the impact of pitching and yaw on the system. When I was in the USN as a nuclear machinist mate, this is reactor system (designated S5G) I qualified on for my “C” school back in the late ’80’s. It’s also what showed me that someone who is 6’3″, 210# doesn’t belong on subs. Yes I knocked myself out once, came close many more times and had a hard time squeezing into some of the areas.
So Ladies and Gentlemen, Technically Carter might of gone to school and actually worked with/on the same design as the Nautilus while not actually serving on the Nautilus. I don’t know if he did or not but if he did could see him using “I trained on the Nautilus” rather than go into detail of what he really did. Could of even been at that time he wasn’t allowed to talk about what was going on at INEL.
Of note, that’s also where the first test reactor was for the Army. It had a very nasty accident, killed several people and the Army wasn’t allowed to play with reactors again.

Reply to  philjourdan
May 17, 2017 2:45 pm

Note that environmentalists have been opposed to dams for decades now. This paper will just give them another “data” point.

Cyrus P Stell
Reply to  Retired_Engineer_Jim
May 17, 2017 4:36 pm

Oh the cognitive dissonance jangles from here. Of course the Green Mob will glom onto this declaring it as “proof” that not only should ALL dam construction cease NOW, but of course we should set about deconstructing (can I blow one up? That would be fun!) all existing dams regardless of how many people die as a result, and never acknowledge this is one more data point proving their beloved Climate Change models are so full of errors and omissions as to be worthless in forecasting anything!

seaice1
Reply to  Retired_Engineer_Jim
May 18, 2017 5:26 am

“Oh the cognitive dissonance jangles from here”
It certainly does.Cyrus P Stell demonstrates one of Scott Adams’s indicators for cognitive dissonace. “An absurd absolute”, which is a restatement of the other person’s reasonable position as an absurd absolute.

Tom Halla
May 17, 2017 11:47 am

What would seem to be the real effect is the change in biological use of the sediments from not reaching the ocean or staying in the natural river bed. It would seen to change mostly the rate and location of the use of the nutrients, not their eventual use.

MarkW
Reply to  Tom Halla
May 17, 2017 1:00 pm

The depth of the water could influence how quickly the nutrients are recycled.

Roger Dewhurst
Reply to  Tom Halla
May 17, 2017 3:36 pm

All dams will silt up eventually. As they do there will be much wringing of hands and gnashing of teeth. When a dam ceases to provide electricity because its storage volume has been filled with silt or sand is it abandoned and the new soil left for agriculture or is a section blasted away to allow the accumulated silt and sand to be washed downriver to the next dam or the sea? I think that the most likely outcome is the removal of the turbines allowing the river to flow free, freeing up some some land for farming. The question then is where is the power that the country requires? Finally it will come back to nuclear power because there will be nothing else. So we might as well start on that now.

MarkW
Reply to  Roger Dewhurst
May 18, 2017 6:44 am

Since the power for the turbines comes from falling water, I don’t see how the reservoir silting up will prevent it from generating electricity.
Of course the lack of storage means that the amount of electricity generated will have to come from the flow of the water directly, with minimal ability to modulate output based on demand.

Logoswrench
May 17, 2017 11:48 am

Note: The novel method in no way mirrors reality and will be used to determine all future policy.

Bruce Cobb
May 17, 2017 11:54 am

Well dam. There we go again, changing the environment to suit us. With environuts, we’re dammed if we do, and dammed if we don’t.

Louis
May 17, 2017 12:00 pm

“We’re essentially increasing the number of artificial lakes every time we build a dam.”
So what’s the difference between an “artificial” lake and a natural one? And why are artificial lakes worse?
Are Beaver dams artificial or natural? Should beaver be exterminated to benefit the environment? If preventing a new lake is good, why isn’t draining an old lake good for the environment? Would it help to drain all the lakes in the world? Inquiring minds want to know.

Clyde Spencer
Reply to  Louis
May 17, 2017 12:23 pm

My thought exactly, Louis. However, the beaver population has been reduced considerably after beaver-felt hats became popular. Farmers aren’t too fond of the critters flooding their fields, either.

Reply to  Louis
May 17, 2017 12:54 pm

Artificial lakes use Aspertame.

Robert Anthony DUNCAN
Reply to  philjourdan
May 17, 2017 1:52 pm

Hehehe. 🙂
Nice one 😉

MarkW
Reply to  Louis
May 17, 2017 1:01 pm

At least the summary did not imply that new lakes were good or bad, just not fully understood.

Louis
Reply to  MarkW
May 17, 2017 1:42 pm

They may not have said it outright, but they certainly implied it by their tone. When you use loaded terms, such as saying that new dams have “significant impacts,” or “ongoing dam construction impedes the transport of nutrients…,” does that imply something good to you?

MarkW
Reply to  MarkW
May 17, 2017 2:16 pm

No, it sounds like they are stating facts.

Reply to  Louis
May 17, 2017 2:22 pm

>>
Should beaver be exterminated to benefit the environment?
<<
Good point. They also cut down trees without the proper permits.
Jim

Reply to  Jim Masterson
May 17, 2017 3:42 pm

Here in Mill Creek, Wa,, beavers are causing trouble with flooding (https://www.heraldnet.com/news/troublesome-dams-in-mill-creek-fixed-by-the-beaver-deceiver/). The city is spending up to $6 million dollars to fix the problem. A couple of bullets would be far cheaper. Even trapping and moving would be cheaper. Nope, environmentalists like spending money on stupid and costly solutions (even if the “beaver deceivers” work).
Jim

Crispin in Waterloo
Reply to  Jim Masterson
May 17, 2017 8:45 pm

Jim
There are hilarious stories about beaver dams on the Alaska highway during construction in the book ‘Six War Years, the sequel to the well known Ten Lost Years about the Depression in Canada.
The local Canadians made money blowing up beaver dams for the American contractors being careful never to kill the beavers. That made beavers cash cows.

May 17, 2017 12:01 pm

Carbon cycle, my ass!
The inland ponds and lakes created by dams change the water vapor content in the air in the area. Since water vapor is a stronger greenhouse gas than CO2, the study should have been about the water vapor concentration in different heights above the dams.

Keith J
Reply to  Steinar Jakobsen
May 17, 2017 1:36 pm

Drop in a bucket. Yes, lakes increase evaporative losses but compared to oceans..
The net effect of water vapor is negative through latent heat effect bypassing half of the atmosphere and through albedo increase.

Roger Dewhurst
Reply to  Keith J
May 17, 2017 3:39 pm

I think that evaporation from a free water surface may well be less than evapotranspiration from fast growing vegetation!

tadchem
May 17, 2017 12:08 pm

The water trapped behind dams on earth covers 258,570 square kilometres: https://www.currentresults.com/Environment-Facts/number-reservoirs-in-world.php
“… approximately 360 million square kilometers (140 million square miles), or 71 percent, are represented by the oceans and mariginal seas.”
http://hypertextbook.com/facts/1997/EricCheng.shtml
258,570 square kilometers / 360 million square kilometers = 0.000718, or 0.072%.
A drop in the proverbial bucket…

Bryan A
Reply to  tadchem
May 17, 2017 12:33 pm

About twice CO2’s relative atmospheric concentration
Must be Trace Water

Crispin in Waterloo
Reply to  Bryan A
May 17, 2017 8:51 pm

Water vapour? It is up to 40,000 ppm.
Typical measurements are in the 10,000 range but it is highly variable. It radiates in the IR band like crazy. If you had IR vision, water would look as black as oil.

tty
Reply to  tadchem
May 17, 2017 12:54 pm

The Great Lakes are about 244,000 square kilometers. Throw in Lake Winnipeg (24,000 square kilometers) and you have topped all those 70,000 dams.

Samuel C Cogar
Reply to  tty
May 18, 2017 5:08 am

Then throw in the Caspian Sea, ……. 371,000 km2 (143,000 sq mi). …
The Caspian Sea, located in Kazakhstan. Russia, is the largest enclosed inland body of water on Earth by area.

Neil Jordan
May 17, 2017 12:08 pm

I am shocked, shocked at this research. The climate authorities insisted that the science was settled.

Bryan A
Reply to  Neil Jordan
May 17, 2017 2:24 pm

But it has settled…settled to the bottom of the effluence barrel

commieBob
May 17, 2017 12:10 pm

Dams have a big effect on the surrounding climate. link Because there are a lot of dams, they have an effect on the global climate. The irrigation resulting from dams also has an effect on the climate. link I’m guessing that the direct and indirect effects of the impounded water dwarf the effect of any CO2 dissolved in that water.

Louis
Reply to  commieBob
May 17, 2017 12:19 pm

“Dams have a big effect on the surrounding climate.”
But are such effects on the climate net positive or negative? Just because something has an effect on the climate, doesn’t mean it’s bad. That goes for CO2 as well. Why is it always assumed that any effect or any change has to be bad?

MarkW
Reply to  Louis
May 17, 2017 1:03 pm

That’s why they need to be paid to study the impact. To find out if it is good, bad or just different.

May 17, 2017 12:11 pm

Trap 1/5. Which means they don’t trap 4/5. Ditto other nutrients, as is related to water release thru hydro turbines and navigation locks. Much ado about very little. Another hyped pretty useless PhD thesis.

Rick C PE
Reply to  ristvan
May 17, 2017 1:51 pm

Apparently all the good subjects for a climatology PhD thesis were already used. They’ve been scraping the bottom of the barrel for years.

Crispin in Waterloo
Reply to  ristvan
May 17, 2017 8:55 pm

A PhD thesis doesn’t have to be useful good, it has to be novel. I’d say the story finds a few novel things, but hardly unexpected.
Dams are net warming and that is a good thing. They help stabilise the temperature in continental climate regions.

mikewaite
May 17, 2017 12:12 pm

Perhaps this work can provide ammunition for those sceptical of the proposed Swansea tidal lagoon to be built between the outlets of rivers Neath and Tawe in south Wales .
The mean depth of the water at full tide, from the diagram in the link below , appears to be about 3m . Still for some of the time, easily warmed by the sun , a breeding ground for algae and mosquitos?
http://subseaworldnews.com/wp-content/uploads/2014/05/Wales-Directors-Form-Swansea-Bay-Tidal-Lagoon-Advisory-Group.jpg
I know that corn mills have been driven by tidal power in the past , but this is a vastly different scale .
Have this group looked at tidal lagoons to allay my fears at a project too politically loaded to be turned down on economic grounds .

tty
Reply to  mikewaite
May 17, 2017 12:18 pm

Mosquitoes breed in fresh water.

Neil Jordan
Reply to  tty
May 17, 2017 1:39 pm

Except for the black salt marsh variety:
http://entnemdept.ufl.edu/creatures/AQUATIC/aedes_taeniorhynchus.htm
They have been found in CA coastal marsh areas, too.

pbweather
Reply to  tty
May 18, 2017 8:13 am

Not true. I have seen plenty of them in brine water in stagnant rock pools near the ocean in Australia.
http://medent.usyd.edu.au/arbovirus/mosquit/saltwet.htm

Roger Dewhurst
Reply to  pbweather
May 18, 2017 1:32 pm

And carry the Ross River virus.

bitchilly
Reply to  mikewaite
May 17, 2017 3:23 pm

i have a hard time believing the swansea tidal lagoon will ever be built.

John
May 17, 2017 12:14 pm

I see. Pick your favorite subject and either blame it on “climate change”, or say that it causes it. Then study it using confirmation bias to prove it.

Joel Snider
May 17, 2017 12:14 pm

I told you dams have been on the Greenie demolition list for decades now… although pretty much everything is, anymore.

Dave
May 17, 2017 12:14 pm

I wonder what the environmental impact of installing wind farms or solar arrays is? Seems like solar arrays reduce the ability to grow vegetation that could be a carbon sink, and wind farms cut down carbon sinks…

Bryan A
Reply to  Dave
May 17, 2017 12:37 pm

At least Land Mounted Solar Arrays can provide shade for the Desert Tortise during the Mid Day Sun (about the most they really can do)

Crispin in Waterloo
Reply to  Dave
May 17, 2017 8:58 pm

A two megawatt wind turbine has about 250 tons of materials that must be sourced, processed and transported. They have a huge environmental impact. They must also be backed up by, preferably, hydro power stations which require large dams.

Samuel C Cogar
Reply to  Crispin in Waterloo
May 18, 2017 6:03 am

Is it not a fact that the aforesaid 250 tons of materials, per each wind turbine location, an increase in the total “Heat Island” infrastructure …. and thus a potential cause that exacerbates increases in near-surface air temperatures (AGW)?

Bulaman
May 17, 2017 12:15 pm

Personally I think that the area of land under irrigation is probably responsible. H2O is numero uno in the greenhouse and the massive expansion of land area with added H2O looks to correlate well with the (natural) changes occurring. No water = no food dilemma for the watermelons..

Bryan A
Reply to  Bulaman
May 17, 2017 12:38 pm

Not really a delima at all. Watermellons want fewer seeds anyway and would probably prefer all but themselves to be seedless

MarkW
Reply to  Bryan A
May 17, 2017 1:05 pm

Doctor’s have developed a procedure that can make guys seedless.

MarkW
Reply to  Bryan A
May 17, 2017 1:06 pm

and every guy in the room winces.

Bryan A
Reply to  Bryan A
May 17, 2017 2:25 pm

We’re talking about watermellons not seedless grapes

Hats off...
May 17, 2017 12:18 pm

“…reservoirs are poorly represented in current climate change models.”
I always knew climate models discriminated against dams. “Ribbons for everyone!” I say.

tty
May 17, 2017 12:21 pm

If reservoirs are so important, how about lakes. How any dams does it take to equal The Great Lakes? Or Lake Baikal? Are those less “poorly represented” in climate models?

Svend Ferdinandsen
Reply to  tty
May 17, 2017 1:23 pm

I wonder if wind turbines and solar cells are also badly represented in climate models?
I believe they are, so here you have a new study.

Crispin in Waterloo
Reply to  tty
May 17, 2017 9:00 pm

In South Africa there are only about five tiny lakes. The biggest would be barely a pond in Ontario. They do however have Great Dams instead. Massive ones. They definitely affect the local climate very positively.

Don K
May 17, 2017 12:23 pm

Well that’s that then. Those damn dams have to go.
To think… we might have saved the planet if we’d just let the Feather River take out that climate destroyer at Oroville.

May 17, 2017 12:29 pm

Gee another X causes climate change story.
Lets control/limit/remove X.
Oh teh stupidity of it all.
Andrew

Resourceguy
May 17, 2017 12:33 pm

So FDR did it, along with George Bush…..on whatever it is.

tty
May 17, 2017 12:37 pm

To put those 70,000 reservoirs into proportion.
Finland has 190,000 lakes larger than 1 hectare (2.5 acres), Sweden has about 100,000. Canada has 32,000 lakes larger than 3 km2 (about 1.2 square miles) while the number of smaller lakes is about 2,000,000. Russia has 2,750,000 lakes of which about 50,000 are larger than 1 km2. The US has 120,000 lakes larger than 10 acres.

MarkW
Reply to  tty
May 17, 2017 1:07 pm

Doesn’t Minnesota have 10,000?

tty
Reply to  MarkW
May 17, 2017 1:46 pm

Very likely. Recently glaciated areas always have lots and lots of lakes. Quite likely North Dakota has even more if you count “prairie potholes”.

Crispin in Waterloo
Reply to  MarkW
May 17, 2017 9:02 pm

Minnesota has 10,000 and Manitoba has 100,000, but who’s counting?

May 17, 2017 12:38 pm

Irrigation, especially spray irrigation, puts about 100 times as much water vapor into the air as everything else combined.

Crispin in Waterloo
Reply to  Dan Pangburn
May 17, 2017 9:03 pm

Thanks for that Dan
Quite right. Irrigation, often provided by dams, is a major source of the most important GHG.

May 17, 2017 12:41 pm

Doubtless, yet another study undertaken by recently graduated scientist’s, with no life skills whatsoever, at the behest of their all seeing, all knowing green professor, focussing on one single, tiny element of a massive, social, engineering, environmental, beneficial, genuinely clean, energy producing project that will last for hundreds of years (well OK, submerging entire Welsh or Chinese communities isn’t exactly social).
My point being, is that it seems to me that the research into a great many of these studies is done by kids who are wet behind the ears.
There’s a saying I can’t quite remember, but it goes something like – If you’re not a socialist before you’re 30, you have no heart. If you’re a socialist after you’re 30, you have no sense.
With senseless educators, these impressionable kids are led down the path of green socialism, indoctrinated, and blinded by political idealism they don’t understand.
Am I talking out my a*se? Well possibly, other than my wife runs a University department with 50 or 60 lecturers including Phd qualified staff, and her observation is that the most sensible amongst them are the second/third generation immigrants (so not immigrants at all) who actually maintain touch with reality, having relatives overseas.
The real whacko, nut job, green socialist fanatics, are the indigenous white characters who enjoy their holiday to a Spanish multiplex hotel every year, and maintain they are seasoned travellers.

Warren Blair
May 17, 2017 12:41 pm

An accomplished Scholarship fiend . . . wow!
https://uwaterloo.ca/ecohydrology/people-profiles/taylor-maavara
Taylor Maavara’s fantasy World ultimately paid for by us.

blcjr
Editor
May 17, 2017 12:43 pm

About that 90% figure…
Around half of the world’s rivers now have one or more large dams on them and the total amount of water stored in the world’s reservoir is around 7000 km3, which amounts to nearly a sixth of the total annual riverflow in the world. Nearly two-thirds of the world’s 227 largest rivers are dammed.”
J.A.A. Jones, Water Sustainability: A Global Perspective, Routledge, 2014, p. 117.

tty
Reply to  blcjr
May 17, 2017 12:58 pm

7,000 km3 is less than a third of the water in The Great Lakes (or Lake Baikal for that matter).

Ron Williams
May 17, 2017 12:51 pm

Good thing they didn’t declare that the increased surface area of dammed reservoirs caused more evaporation of water vapor to the atmosphere and therefore more ‘artificial’ H2O in the atmospheric systems. Water bodies globally on average evaporate about one ton per sq m2 per year so this additional water vapor in the atmosphere is a ‘new’ GHG (H2O) had the dam never impounded the water to begin with. Good thing they don’t consider H2O water vapor a GHG, otherwise it would really mess up their accounting of CO2 in the warming budget. Obviously this additional water vapor turns to precipitation at some point, so might also be part of the increased rainfall in flood prone regions.
With tens of thousands of square miles of new reservoirs the last 100 years, I see no accounting for this fact of increased water vapor in the atmosphere directly as a manmade cause, and that the impounded water behind the dams would add an inch of water to the ocean sea level rise. I know, this is probably an inconvenient truth to the skeptics, but I am just being skeptical here. My point being, is that there are many other causes to the so called AGW theory (which hasn’t provided very much warming by the way) so how can CO2 be responsible for all AGW climate change issues?

tty
Reply to  Ron Williams
May 17, 2017 1:11 pm

“the impounded water behind the dams would add an inch of water to the ocean sea level rise.”
7,000 km3 is equal to slightly less than 3/4 of an inch, and it is probably balanced by draining of natural lakes and wetlands in any case.
“Obviously this additional water vapor turns to precipitation at some point, so might also be part of the increased rainfall in flood prone regions.”
Also, since evapotranspiration is more important for transporting heat away from the Earths surface than infrared radiation it will also cool the global climate a bit.
.

Ron Williams
Reply to  tty
May 17, 2017 1:36 pm

I guess it depends where we source the info from. Some of the results I got were as high as 1.25″ for the additional SLR so I averaged it to 1″. Even 3/4″ of water over the entire ocean is a slug of water. If natural SLR has been about 6″ in the last 100 years or so, then the impoundment of 3/4″ to 1″ water is a good thing and represents about 20% of that increased oceanic water, although a lot of the SLR is thermal expansion.
The additional evapotranspiration would be from the increasing plant growth as a result of the additional greening of the planet due to rising CO2. Good point. I think you are meaning that just plain old evaporation would transport latent heat away resulting in local cooling. But more water vapor in the atmosphere will mean more precipitation, somewhere. The point being that increased rain caused flooding is all the fault of CO2 induced warming they say, although we are proving that there are multiple causes to AGW so CO2 can’t be the sole source of all the perceived problems with man made CAGW.

tty
Reply to  tty
May 17, 2017 1:58 pm

“The additional evapotranspiration would be from the increasing plant growth as a result of the additional greening of the planet due to rising CO2. Good point. I think you are meaning that just plain old evaporation would transport latent heat away resulting in local cooling.”
No. Any water evaporated, whether from plants, lakes, dams or oceans is relatively quickly transported to high altitude by convection. There it condenses and the freed latent heat is radiated away into space. This is a considerably more important heat transport mechanism than IR radiation, though you have to dig into the physics to find out, because it is never ever mentioned explicitly by “climate scientists”. And, yes, any water evaporaten anywhere always comes back down as rain/snow somewhere.

Reply to  tty
May 17, 2017 3:06 pm

Also, since evapotranspiration is more important for transporting heat away from the Earths surface than infrared radiation it will also cool the global climate a bit.

*more important* than IR?? HA!
…except for all that cooling that happens at night due to infrared radiation

Reply to  tty
May 17, 2017 3:17 pm

tyy:

No. Any water evaporated, whether from plants, lakes, dams or oceans is relatively quickly transported to high altitude by convection.

The absolute term of “any water evaporated” (implying all water evaporated) is a poor choice of words because if you look at global IR satellite imagery, deep convection I relatively rare so that statement is false

freed latent heat is radiated away into space.

1) that ‘freed latent heat’ is internal to the cloud and only abt 3F warmer than surrounding atmosphere with the equivalent dry parcel being lifted so…no, that is not correct either.
2) tops of the clouds are cold not hot (this is obvious from Skew-T charts & satellite imagery) and if you see hot bare ground next to a cold cloud top in that imagery, it is obvious clear sky is a better radiator of heat than any cold cloud top…especially tall cumulonimbus clouds which can be as cold a -80C.

This is a considerably more important heat transport mechanism than IR radiation

Obviously it’s not.

tty
Reply to  tty
May 17, 2017 3:22 pm

“*more important* than IR?? HA!”
It is. IR transports away 66 W/m2, Evapotranspiration 78 W/m2, Thermals (=warm air) 24 W/m2
Those are IPCC figures, though their image is carefully contrived so as to hide this embarrasing fact:
http://wg1.ipcc.ch/publications/wg1-ar4/faq/fig/FAQ-1.1_Fig-1.png

tty
Reply to  tty
May 17, 2017 3:42 pm

JKrob
I’m sorry to have to say this, but you are ignorant of basic atmosphere physics.
“The absolute term of “any water evaporated” (implying all water evaporated) is a poor choice of words because if you look at global IR satellite imagery, deep convection I relatively rare so that statement is false”
If the statement was false water vapour would be continuosly accumulating in the atmosphere. It isn’t. All evaporated water comes back down, and fairly quickly too. Ten days is the figure usually given.
“tops of the clouds are cold not hot (this is obvious from Skew-T charts & satellite imagery) and if you see hot bare ground next to a cold cloud top in that imagery, it is obvious clear sky is a better radiator of heat than any cold cloud top”
Nope. Ever heard of greenhouse gases? They largely prevent LWIR from the ground reaching space. And the reason those cloud-tops are cold are because they are at an altitude where most LWIR is free to radiate away into space (which is at 3 K). At about 5-6 km altitude they are at Earth’s equilibrum temperature, i e 255 K. Of course this is an average figure, it varies with season and geographically.

Retired Engineer John
Reply to  tty
May 17, 2017 5:13 pm

The temperature of lake water does not exceed 31C. This does not depend upon if the sky is clear or cloudy. All temperature scales for lakes end at 31C. Why, have you ever noticed when walk on a lake bottom where the water is not flowing, you kick up a grey cloud. That cloud is calcium carbonate. When water gets near 28C, it starts releasing carbon dioxide and that carbon dioxide combines with calcium to from calcium carbonate. In the processes, energy is taken from the water to complete the chemical bonds. This removal of heat is sufficient to limit water temperature to less than 31C.

Wayne Delbeke
Reply to  tty
May 17, 2017 5:57 pm

Ron Williams: Sources for the 1″ lower sea level or whatever? Curious. A dam attenuates the peak flow. There is additional evaporation and probably infiltration but overall close to the same amount of water gets to the ocean, it just gets there with a bit of lag – at least in temperate zones. I keep seeing people inferring that reservoirs cause less water to get to the ocean (which might be ever so slightly true in desert regions) but generally they just reduce the peak flow. Of course I studied hydrology 50+ years ago so maybe there is something new I don’t know about. Even much of the infiltrated or evaporated water finds its way back to another water basin and eventually to the ocean.
Here is a sample of flood routing (which includes through the Oroville Dam):
http://www.damsafety.org/media/Documents/FEMA/TS22_DambreachModeling/20_PRESENTATION.pdf
Others, just references to routing.
http://ce531.groups.et.byu.net/syllabus/homework/hw27/index.htm
http://www.ce.utexas.edu/prof/mckinney/ce374k/Overheads/16-ReservoirandRiverRouting.pdf

Reply to  tty
May 17, 2017 6:42 pm

“I’m sorry to have to say this, but you are ignorant of basic atmosphere physics.”
and I’m sorry to say you are ignorant of basic meteorology…and you trust IPCC images which, with your example, is what is referred to as a gross oversimplified model (with some errors, I might add).
“All evaporated water comes back down, and fairly quickly too”
but not solely through deep convection as you claim. There are a variety of other precipitation processes (as well as the formation of dew, which *also* removes water vapor from the air without convection). If you knew anything about meteorology, you’d know that.
“Ever heard of greenhouse gases? They largely prevent LWIR from the ground reaching space.”
now that is just ignorant. I never said or implied water vapor does not impact IR radiation to space but it is not as much as you claim because nights still cool down under a clear sky even with water vapor present. Also, if water vapor was as big effect as you claim, not heat would be reaching the satellites to detect which it obviously does. Water vapor only occupies a portion of the total IR spectrum. It’s not all or nothing.
“And the reason those cloud-tops are cold are because they are at an altitude where most LWIR is free to radiate away into space…”
Now that is just laughable. Cloud tops reflect the temperature of the level of the atmosphere they are at (Equilibrium Level – look it up) and it is colder than the surface solely due to the atmospheric laps rate present at that location (look that up too). You obviously have no clue about meteorology.
You obviously have no references to back up your claims & I have around 100 years operational meteorology references to draw from so…I guess they are all wrong & your right.

tty
Reply to  tty
May 18, 2017 2:17 am

“ There are a variety of other precipitation processes (as well as the formation of dew, which *also* removes water vapor from the air without convection). If you knew anything about meteorology, you’d know that.”
Yes, and they all liberate the same amount of latent heat, but convective precipitation is a very large part of all precipitation, particularly in the tropics around the ITCZ (where most rain falls):comment image
Here you can watch the convection cells swell and collapse every day
https://www.smhi.se/vadret/nederbord-molnighet/satellit-jorden
“Now that is just laughable. Cloud tops reflect the temperature of the level of the atmosphere they are at (Equilibrium Level – look it up) and it is colder than the surface solely due to the atmospheric laps rate present at that location (look that up too). You obviously have no clue about meteorology.”
Actually I have a degree in meteorology, but that is neither here nor there. However, have you never wondered why there is a lapse rate, and why it happens to be almost exactly equal to the amount of energy needed to lift air of the local relative humidity against the local gravitational field? Yes, I know it varies a bit around that figure, and that this variation is a large part of what meteorologists do for a living.
d know that.”
“I never said or implied water vapor does not impact IR radiation to space but it is not as much as you claim because nights still cool down under a clear sky even with water vapor present. ”
They do indeed, and they would no matter how much GHG are around, because that big yellow thing in the sky isn’t there. If the night was long enough (and heat didn’t transfer from the day side) temperature would ultimately sink to a little above 3 K. By the way, have you noticed how much faster the temperature falls at night in deserts and arctic areas where there is little water in the atmosphere?

Ron Williams
Reply to  tty
May 18, 2017 10:57 am

Wayne Delbeke May 17, 2017 at 5:57 pm The 1″ of additional sea level is the amount of water that is stored and impounded behind the dam. If all dams released the entire water volume then all those tens of millions of acre feet storage would increase the ocean level by the amount of water behind the dam which is calculated to be .75″ to 1.25″. Most dams are operated at FSL (Full Supply Level) for maximum efficiency such as electricity generation. That is considered ‘dead storage’ for the water that is stored behind the dam under the FSL. After the dam is full of water, then what you say about the river eventually flowing to the ocean is correct. It is delayed storage that is stored behind the dam that we are talking about regarding what the ocean level would have been had no dams ever been built. Pretty straight forward logic, so wonder how you arrive at a different conclusion?

May 17, 2017 12:56 pm

“It found that man-made dam reservoirs trap nearly one-fifth of the organic carbon moving from land to ocean via the world’s rivers.”

I have a feeling (like many studies) this is a way to phrase the study in a way which makes it sound more significant than it is.
I suspect that the amount of organic carbon moving from land to ocean is significantly less than the amount of carbon dioxide emitted from energy sources. It’s probably orders of magnitude less.
It other words, it makes the scientists feel good about the importance of their study (and I’m sure there are impacts in the river), but it does not make the results significant.

Louis
Reply to  lorcanbonda
May 17, 2017 1:47 pm

Do old lakes formed by natural dams trap carbon or nutrients differently than man-made dams? How is one different from the other?

tty
Reply to  Louis
May 17, 2017 2:07 pm

The water level usually changes faster and more erratically in dams. This probably makes them less efficient sediment traps. Occasionally dams are built specifically for trapping sediments (e. g. from old mines or contaminated landfill sites upstream). In such cases one always tries to keep the water-level as constant as possible to encourage plant growth in the dam and enhance sediment capture.

Peta from Cumbria - now Newark
May 17, 2017 12:58 pm

I know you’ll find this hard to believe but, recently I’ve been studying the role of fluff in my navel. Quelle horreur that even without a superduper mega willy enhancer computer that because I am the Key researcher, I have found out what a Key role this Key fluff plays in my Key navel.
It is simply gobsmackingly Key what a Key role it plays.
At least its a bit of fun and I try to positive about it, unlike these Key researchers. Why so relentlessly negative.
These lakes behind dams are massive sediment traps and as such should be regarded as a fantastic resource.That stuff, muddy, dirty, smelly and generally yuk is the concentrated goodness from large areas of land, farmland, forest whatever. It is all the trace elements and micronutrients plants need to grow – despite the assertions from many parties that CO2 is the only thing plants seem to need.
That smelly dirty yuk should be dredged out of the lakes, taken back up the hill it washed down and put/spread/dispersed across the land it originally came from
Dams are a brilliant things for doing that because otherwise all this goodness goes out into the sea and is lost, pretty well, forever.
Why don’t these supposedly educated people know this?

MarkW
Reply to  Peta from Cumbria - now Newark
May 17, 2017 1:09 pm

My wife is my key researcher. Every day I’m asking her, “Honey, do you know where I left my keys?”

Ron Williams
Reply to  Peta from Cumbria - now Newark
May 17, 2017 1:16 pm

Many dams have been designed with low level conduits to not only release sediments at freshet/high water flows, but also to release lower temperature water into the river to try and simulate what natural water temps would be if not for the dam.
Great idea on using the sediment from the bottom of the reservoirs. Probably the best pre-fertilized soils on earth. The Nile is one good example of the river silt being blocked. Having said all this about dams, I still think dams are very net positive to humans, although perhaps we can be smarter on how we use them and the precious fresh water they store.

Dinsdale
May 17, 2017 1:06 pm

WTF is “organic carbon”? Organic chemistry is a chemistry subdiscipline involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.
And when did silicon become a “nutrient”? Silicon is much more abundant than any other element, apart from the oxygen. It constitutes over 25% of the solid Earth’s crust.
Apparently no rational editor looked at this.

tty
Reply to  Dinsdale
May 17, 2017 1:16 pm

I guess diamonds and possibly graphite might be classed as “inorganic carbon”. The carbon in (natural) diamonds has probably never been part of organic compounds, graphite is more doubtful, it might well be highly modified organic materiel in some cases.

tty
Reply to  Dinsdale
May 17, 2017 1:21 pm

And, yes, dissolved silicon is a nutrient. Ask any diatom or radiolarian (or even grass for that matter). They all take up dissolved silica from water and use it as a structural material, just av we do with calcium.

Reply to  Dinsdale
May 17, 2017 7:30 pm

“Inorganic carbon” is probably carbonate or bicarbonate. These are in solution, so they won’t get trapped behind dams. “Organic carbon” is presumably plant debris. which will get trapped. So there is some sense and logic there; don’t be too quick to dismiss everything just because it’s “green”.
Previous enviro-gripes about dams have focused on methane from trees and stuff buried by reservoirs. Also organo-mercury compounds allegedly leached from flooded soils and vegetation. These people have invented a whole new class of environmental destruction – “interrupting the carbon cycle”. Oh the humanity!

seaice1
Reply to  Smart Rock
May 18, 2017 3:44 am

Organic chemistry is the study of carbon containing compounds. However, some carbon containing compounds are considered inorganic.
From wikipedia: “For historical reasons discussed below, a few types of carbon-containing compounds, such as carbides, carbonates, simple oxides of carbon (for example, CO and CO2), and cyanides are considered inorganic.[3] The distinction between organic and inorganic carbon compounds, while “useful in organizing the vast subject of chemistry… is somewhat arbitrary””
Whilst arbitrary, the distinction between organic and inorganic carbon is common and useful.

Rick K
May 17, 2017 1:07 pm

DAM!

Bruce Cobb
May 17, 2017 1:12 pm

Dams – the new fudge factor for GCMs. The more they tweak them, the more they fail.

J Mac
May 17, 2017 1:16 pm

Glacial Lake Missoula had verifiable and enduring environmental impacts on both Montana and Washington states, but that was a result of global warming 15,000 years ago!
http://www.glaciallakemissoula.org/story.html

tty
Reply to  J Mac
May 17, 2017 1:31 pm

Glacial Lake Missoula at 2,100 km3 was small fry. Glacial Lake Agassiz was 15,000-40,000 km3 and the West Siberian ice-dammed lake during the penultimate glaciation was 75,000 km3.
Now that is what i call a dam. And all three drained catastrophically due to global warming. Must have been all those damn neanderthalers with SUVs.

Keith J
Reply to  tty
May 17, 2017 1:42 pm

Barney and Fred ? Yabba dabba do!

Catcracking
May 17, 2017 1:25 pm

Does this mean things are better or worse than they thought re the impact to Carbon Dioxide. Are the models even much worse than we already know?
“The study, conducted by researchers at the University of Waterloo and the Université libre de Bruxelles, appears in Nature Communications. It found that man-made dam reservoirs trap nearly one-fifth of the organic carbon moving from land to ocean via the world’s rivers.
While they can act as a significant source or sink for carbon dioxide, reservoirs are poorly represented in current climate change models.”

tty
Reply to  Catcracking
May 17, 2017 1:39 pm

Very likely they don’t have the faintest idea whether they are net sources or sinks.
On balance I think more likely sinks. Lakes (and dams) trap organic sediment which, if it continued to the sea would probably get eaten and metabolized into CO2. On the other hand they also trap some nutrients that would otherwise be used by marine autotrophs, thereby absorbing CO2, but then most of those autotrophs would get eaten and metabolized back into CO2….

Sandyb
May 17, 2017 1:29 pm

If I could use the bullshit from one of these “studies” in my garden I could feed my entire neighborhood.

May 17, 2017 1:50 pm

Torpedo the dams! Full speed reverse!!

RWturner
May 17, 2017 1:52 pm

A measureable effect from reducing the DOC, silica, and phosphorus nutrients delivered to the ocean via rivers? I doubt it, especially since there is fertilizer runoff these days and iron is the limiting factor for most ocean primary production. However, there is certainly a measureable effect from reduced sediment load in general, and nowhere is it more noticeable than the Mississippi Delta.

RWturner
Reply to  RWturner
May 17, 2017 1:55 pm

Perhaps some of the energy produced by hydroelectric should go into dredging the trapped sediments and sending them downstream.

tty
Reply to  RWturner
May 17, 2017 2:09 pm

“and nowhere is it more noticeable than the Mississippi Delta.”
The Nile Delta is in at least as much trouble as the Mississippi Delta.

H. D. Hoese
Reply to  RWturner
May 17, 2017 3:48 pm

Limiting phytoplankton nutrients off the Mississippi Delta have been reported as nitrogen, phosphorus, and silica. There is lots of organic matter and production there. The Aswan dam collapsed the Israel sardine fishery, because the Mediterranean current off the Nile delta goes north.
Is increased carbon dioxide indirectly slowing erosion, therefore sediment and nutrient export, some collected by dams? HMMM?

Roger Knights
May 17, 2017 1:58 pm

I read here in the past that the water behind dams in Siberia catches the cold snow-melt water in the spring and gradually releases it over the summer and fall, during which time it’s warmed in the sun. This warmer water might be a major cause of the decline in arctic sea ice.

tty
Reply to  Roger Knights
May 17, 2017 2:19 pm

Oddly the opposite seems to be the case:
http://onlinelibrary.wiley.com/doi/10.1029/2006JG000370/full

Walt
May 17, 2017 2:14 pm

Is this supposedly news? The consequences of changes down stream are an open question. How do the changes measure up against what happened when steam flows were unobstructed?

Ron Clutz
May 17, 2017 2:35 pm

A previous study sought to raise alarms about dams by claiming methane emissions will rise from the reservoirs. Serious researchers found otherwise.
Over the last 30 years, CH4 in the atmosphere increased from 1.6 ppm to 1.8 ppm, compared to CO2, presently at 400 ppm. So all the dam building over 3 decades, along with all other land use was part of a miniscule increase of a microscopic gas, 200 times smaller than the trace gas, CO2.
Studies are here: https://rclutz.wordpress.com/2017/02/27/reservoirs-and-methane-facts-and-fears/

Editor
May 17, 2017 2:43 pm

The bottom line of the paper is a no-brainer:

“We’re essentially increasing the number of artificial lakes every time we build a dam,” said Taylor Maavara, lead author and a PhD student at Waterloo. “This changes the flow of water and the materials it carries, including nutrients and carbon.”

Of course dams change flow. How could they not? I see nothing in the above (press release?) that tells me that this is thus important, that it meets any standard of Minimal Climatically Important Difference.
It might — but nothing above shows that it is or even more than “might be”.

toorightmate
Reply to  Kip Hansen
May 17, 2017 5:31 pm

Taylor Maavara has proven that the attribute required to be a PhD student at Waterloo is a total absence of brain cells.

crowcane
May 17, 2017 2:44 pm

1) What is the effect of removing all of those acres of carbon sink which results when the reservoirs behind the newly constructed damns are filled?
2) How much additional carbon sink would be created by the removal of the damns ?
3) Is the difference too small to bother including its effects in the calculations of the models?
4) Has anyone actually performed the necessary calculations to make such determinations?

charles nelson
May 17, 2017 3:03 pm

Forget the Carbon…these things are pumping vast quantities of ‘Water Vapour’ into the atmosphere! We all know that WV is a potent ‘greenhouse gas’!
Throw in the extra WV being pumped into our atmosphere from irrigation and you’re looking at a nightmare, tipping point catastrophic situation.

crowcane
Reply to  charles nelson
May 17, 2017 5:18 pm

I am aware of the difference between CO2 and H2O but I was just wondering if anyone had any idea of the difference. The alarmist seem to emphasize CO2 so much especially when their remarks are intended for the public in general and for the MSM.
I decided several months ago that the only way that I would be able to get at the facts was to take it upon myself to look up and read the various papers and articles and that I could not rely upon anyone else. This site has been a God send in that regard and I am always interested in the comments section for each item posted.

charles nelson
Reply to  crowcane
May 18, 2017 12:50 am

One of the most obvious differences between CO2 and H2O is that CO2= 1/25th part of ONE percent of the atmosphere whereas H2O = >4%<….and is in LIMITLESS supply. I think that's what scientists call 'an order of magnitude'!!

seaice1
Reply to  crowcane
May 18, 2017 5:11 am

crowcane. In this context the big difference is that water drops out of the atmosphere rapidly whereas CO2 does not. If you emit lots of water vapor it does not change the level of water in the atmosphere except locally over a short period.
Imagine a chimney emitting water vapor and CO2. The water vapor would increase humidity. When RH reaches 100% the water vapor condenses and falls to Earth. Quite soon all this added water will be removed from the atmosphere due to increased RH.
In contrast, the CO2 will never condense and fall to Earth but is removed by much slower processes. In a week or so all that water has been removed, but essentially all the CO2 is still there. This is why we are not concerned over water emissions. Emissions make essentially no difference to the level of water in the atmosphere.
We have measured the levels of CO2 in the atmosphere and they have risen by 40% or so – the Keeling curve. The amount of water in the atmosphere has not (substantially) changed over this period.
Whether you think the increase in CO2 is from fossil fuels or some other process, it is undeniable that CO2 is behaving totally differently from water in the atmosphere.

Ron Williams
Reply to  crowcane
May 18, 2017 11:10 am

Seaice 1. Humans are causing additional water vapor 24/7 into the atmosphere that is a much stronger GHG overall than CO2 ever will be. Plus the additional water vapor that does turn to rain is over and above what natural rainfall would have been if not for the anthropogenic water vapor and can be considered responsible for more intense flooding events. Trying to say that human caused water vapor is a non issue is said only so that CO2 can be further demonized according to your religion.

Chimp
Reply to  crowcane
May 18, 2017 11:18 am

Seaice,
It doesn’t matter that water vapor rains out more quickly than CO2 leaves the air. The fact is that there is on the order of 100 times more H2O in the air than CO2. If you believe the pack of lies perpetrated by IPCC and its consensus imps, then more CO2 also means more H2O, which is the only way they can gin up worrisome warming.
CO2 isn’t a pimple on the posterior of H2O. Most of their absorption bands overlap anyway, so any possible effect from CO2 is already swamped by the far more important GHG.

seaice1
Reply to  crowcane
May 18, 2017 3:12 pm

Ron. Humans are adding water, which just as quickly falls out of the atmosphere. It is a condensing vapor. Otherwise we would have something like the Keeling curve for water, showing a steadily increasing level of water in the atmosphere. We clearly do not see this. This is because the extra water falls out of the atmosphere when it condenses. The extra rainfall due to human emissions of water is miniscule compared to the amount of water that evaporates naturally.
Water in the atmosphere is about 15,000GT. Water flux (evaporation and precipitation, which are the same aount) is 505,000GT per year. The flux is much greater than the reservoir. Small additions from humans make no difference to the reservoir
CO2 in the atmosphere is about 710GT. CO2 flux is about 220GT per year. The flux is much smaller than the reservoir. The small additions of CO2 to the atmosphere remain in the atmosphere, resulting in a steadily increasing level. This has been measured and is pretty much solid – unless you wish to question these measurements?
You argue that human emitted water is responsible for more intense flooding events. This sounds like nonsense to me, but perhps you can back this up with some evidence?
Chimp.
“It doesn’t matter that water vapor rains out more quickly than CO2 leaves the air. The fact is that there is on the order of 100 times more H2O in the air than CO2. ”
Nothing I said disputes the relative levels of CO2 and water in the atmosphere. My point is that water we add through emissions does not increase the amount of water in the atmosphere becase it condenses out, whereas the CO2 we emit does increase the level in the atmosphere. Do you disagree with this?
If you do disagree with this,, can you explain why we do not have something like the Keeling curve for water, showing steadily increasing levels of water in the atmosphere that humans have emitted?
No, of course you can’t, because all that extra water has simply condensed out.

Mark Lee
May 17, 2017 3:06 pm

I don’t think the trapped carbon, etc. is the major impact of the dams. Free flowing rivers deposit a lot of dirt, sand, silt, rocks, etc., which act as a counter to beach erosion caused by tides, storms, etc. There can also be a reduction of organic materials that are food to fish and shell fish in the area. I think that dams serve a very useful purpose, but if you’re going to look at a potential negative impact, I don’t think it is carbon.

Michael Jankowski
Reply to  Mark Lee
May 17, 2017 3:41 pm

So urbanization allegedly has a teenie-tiny influence on global temps…but dams certainly do?

michael hart
May 17, 2017 3:49 pm

What they appear to be insinuating is that of the organic carbon (i.e. not CO2 but higher molecules up to and including twigs and leaves) has a different chemical fate if some of it gets stuck for a while behind a damn. I just don’t buy that it will be significantly different in the long term or that the amount is significant on a global scale, even if they were talking about 100% of it and not 20%.

ROM
May 17, 2017 4:21 pm

When those pseudo scientists turn on a tap they expect, demand even that water will flow out of that tap in a never ending stream.
I bet they never ever think of where that water they so depend on for so many things that make their lives so easy compared to those who have no such taps, comes from.
When those pseudo scientists reach for a food and vegie item off the shelves in the super markets I bet they never ever think of where the immense volumes of water that is needed and enables those vegies and food items to grow so prolifically and to be supplied in such quantities and at such low prices, ever comes from.
When they flush their waste down the toilet, I doubt that any of them ever think of or consider their own beliefs and understandings of where the immense volumes of water come from that enables such a huge waste disposal system to operate so efficiently and so unnoticed by the millions of those city’s inhabitants.
A human waste disposal system that is the ultimate key to being able to live in mankind’s cities, cities that are clean and healthy and relatively free from major diseases, cities that now house hundreds of millions of mankind’s numbers,all due to the availability of water in immense volumes from the dams that mankind has built on the rivers of Earth.
Gross hypocrisy and arrogance and ignorance and condescension does not sit well with those elitists who would preach to us on how we proles are ruining the planet by our desire to have a few life sustaining essentials such as water and food made cheaper and more easily available to the human race by building dams and power stations and sewerage systems that use lots of water from dams on river, dams and their waters that make life in mankind’s immense cities habitable and healthy for the billions who now live in those cities.

seaice1
Reply to  ROM
May 18, 2017 5:17 am

This one comes under Scott Adam’s “The Psychic Psychiatrist Illusion”, where the loser of the argument imaginings they can discern the inner thoughts and motives of strangers.

Dr. S. Jeevananda Reddy
May 17, 2017 5:22 pm

Dams and the associated irrigated agriculture increase the evaporation and evapotranspiration locally and regionally [if they are large]. This is known as cold-island effect that counters the heat-island effect. These cause direct impact on climate [like land ocean temperature differences] — though they are local/regional in nature through summation it goes in to global climate. In fact this lead satellite data forming less than half of the ground based data.
With regard to other factors as reported in the article, even with the dams large part of flows join seas/oceans during flood years and protect the environment in less floods years. For example the two mighty rivers of India, Ganga & Brahmaputra are the examples.
The whole process is not as simple as that of the article author thinks.
Dr. S. Jeevananda Reddy

toorightmate
May 17, 2017 5:28 pm

I watched a TV program on beavers last night.
It was the best dam program I have ever seen.

RoHa
May 17, 2017 5:41 pm

Damn!

Bill Illis
May 17, 2017 5:57 pm

Lakes are BAD.
That is why humans like them so much.
I guess the BAD fish also like them and the birds and the reptiles/mammals that congregate around them and the insects and the plants that grow next to them.
All lakes and all life is therefore BAD. Water and wildlife are not environmentally sustainable.

Kurt
May 17, 2017 7:15 pm

What is it that saps critical reasoning skills from climate scientists? Can’t this “department chair” and “co-author” see the utter contradiction between these two sentences, quoted in same paragraph no less:
(1) “Dams don’t just have local environmental impacts. It’s clear they play a key role in the global carbon cycle and therefore the Earth’s climate,”
(2) “For more accurate climate predictions, we need to better understand the impact of reservoirs.”
If you need a better understanding of the “impact of reservoirs” on climate (the plea for research money), how can you already have reached the conclusion that reservoirs play a “key role in . . . the Earth’s climate (the promise of how your research will turn out if you do get the money)?”

seaice1
Reply to  Kurt
May 18, 2017 3:30 pm

There is no contradiction. I do not understand what you are thinking to believe there is a contradiction.
It is obvious that one can identify something as an important contibutor to an effect but also understand that you do not know the exact magnitude of that contribution. Therefore there is no contradiction between identifying a key role and saying better understanding is needed for more accurate predictions.
That is the logical argument, but to illustrate we can use an analogy. You see an army marching towards your border. It would be true to say that the approaching army could play a key role in your countries immediate future.
For a more accurate prediction on the effect on your country, it would be true to say that a better understanding of the approching army is needed.
Please note that the analogy is for illustrative purposes only and does not form part of the actual argument.

hunter
May 17, 2017 8:50 pm

Iimnology is the area of study concerning fresh water bodies and systems. They apparently cycle as much carbon as an ran despite freshwater being tiny fraction of the oceans. They act as net sinks or we would hear about it.

crackers345
Reply to  hunter
May 18, 2017 1:03 am

It’s “Limnology,” not “Iimnology.”

willhaas
May 17, 2017 9:29 pm

Because they might adversly affect climate we must immediately get rid of all devices and structures that hold water or affect its natural flow in any way. That means no more hydroelectric power or any form of indoor plumbing. All streets and roads artificially affect the flow of water so they should be removed as well including all other structures made by Man. You’r not even allowed to cup water in your hands for drinking because it may adversley affect global climate. This is in addition to the idea that we all need to stop making use of any goods and services that make use of fossil fuels in any way. I am sure that if we all abide by what I am saying here we will have a better world.

seaice1
Reply to  willhaas
May 18, 2017 5:22 am

This one comes under Scott Adam’s “An absurd absolute”, where the loser of the argument restates the other person’s reasonable position as an absurd absolute.

Julian Flood
May 18, 2017 3:08 am

Anthony, your site gives me the update Chrome spam.

Patrick MJD
Reply to  Julian Flood
May 18, 2017 6:30 am

WordPress…

seaice1
May 18, 2017 5:19 am

Forrest refuses to engage with science that is not settled.

seaice1
Reply to  seaice1
May 18, 2017 7:57 am

Science is about exploring what could be. If all you want is what we already know is, you are not interested in science.

seaice1
Reply to  seaice1
May 18, 2017 3:17 pm

I will quote you: ” I look forward with keen interest to reading what IS, not what COULD BE.”
When you read what could be, you stopped reading. When someone interested in science reads what could be, they continue because they are interested in what could be.

Reasonable Skeptic
May 18, 2017 9:30 am

Now who am I to pick on respected scientists…. but here goes anyways.
This is from the article:
“Dams don’t just have local environmental impacts. It’s clear they play a key role in the global carbon cycle and therefore the Earth’s climate,” said Philippe Van Cappellen, a Canada Excellence Research Chair in Ecohydrology at Waterloo
Now one of my fervent beliefs is that people will always overstate the importance of their work and this is a primary drive in alarmism. This is a perfect example.
What is a dam? It is simply a barrier that changes a river into a lake. Now, to state the obvious, there are a shit load of lakes out there already and dams have only added a tiny fraction of lakes.
So are dams really a “key” player in the global carbon cycle? Of course not. They may be key in the unknown portion of the global cycle though.
Has anybody ever heard of a scientist stating “This work is a tiny sliver of new information that we can use to help understand nature”. Nope, I didn’t think so.

Gary Pearse
May 18, 2017 10:34 am

Probably alarmed it will also reduce SLR and recharge aquifers. I’ve suggested using selected impoundment to recharge large reservoirs like the Ogallala (world’s largest?) that stretches from Iowa to Texas and San Joaquin Valley, CA. I’ve often wondered why damage designs didn’t include lifting silt sufficient to maintain the river’s burden of silt downstream – a self cleaning system operating hydraulically. Silt is no good for a dam either.

Gary Pearse
Reply to  Gary Pearse
May 18, 2017 10:37 am

‘dam designs’ (illiterate #*¿§¶ language benders).

Wharfplank
May 18, 2017 11:24 am

Why do Leftists hate reliable electricity? Yeah, rhetorical.

May 21, 2017 4:55 am

Let me get this straight. We turn countless square miles of desert into lakes and they conclude that man just changed the climate? No kidding…but what does that have to do with CO2?

May 21, 2017 9:24 pm

Seeing the Forest Through the Trees; Political Ideology and Federal Grants are Blinding Climate “Scientists” From Seeking the Truth
Really? Changes in the carbon in rivers vs lakes is the important factor when building a dam and measuring its impact on climate change? The claim is so absurd it is laughable, and highlights just how corrupt and wasteful Federal spending on climate research truly is. Yes, I know that particular study was paid for by the Canadians, but the same thing happens in the US.
https://co2islife.wordpress.com/2017/05/22/seeing-the-forest-through-the-trees-political-ideology-and-federal-grants-are-blinding-climate-scientists-from-seeking-the-truth/

CRS, DrPH
May 22, 2017 8:53 pm

Thanks, Anthony! Unbeknownst to many, the reservoirs associated with dams are a substantial source of methane produced from microbial digestion of the organics in the sediment. https://www.washingtonpost.com/news/energy-environment/wp/2016/09/28/scientists-just-found-yet-another-way-that-humans-are-creating-greenhouse-gases/?utm_term=.9b535b4cfdf1