Reservoirs play substantial role in global warming

September 30, 2016 by Eric Sorensen
A recent photo of a reservoir on the Snake River in Washington. Credit: Shelly Hanks, WSU Photo Services

Washington State University researchers say the world's reservoirs are an underappreciated source of greenhouse gases, producing the equivalent of roughly 1 gigaton of carbon dioxide a year, or 1.3 percent of all greenhouse gases produced by humans.

That's more production than all of Canada.

Writing in next week's journal BioScience, the WSU researchers say are a particularly important source of , a greenhouse gas that is 34 times more potent than carbon dioxide over the course of a century. Reservoir methane production is comparable to rice paddies or biomass burning, both of which are included in emission estimates of the Intergovernmental Panel on Climate Change, the leading international authority on the subject.

John Harrison, co-author and associate professor in the WSU Vancouver School of the Environment, last month attended a meeting in Minsk, Belarus, to discuss including reservoir emissions in a planned 2019 IPCC update of how countries report their greenhouse gas inventories.

Methane accounts for 80 percent

"We had a sense that methane might be pretty important but we were surprised that it was as important as it was," said Bridget Deemer, WSU research associate and lead author. "It's contributing right around 80 percent of the total global warming impact of all those gases from reservoirs. It's a pretty important piece of the budget."

The BioScience analysis, which drew on scores of other studies, is the largest and most comprehensive look to date at the link between reservoirs and , Harrison said.

"Not only does it incorporate the largest number of studies," he said. "It also looks at more types of greenhouse gases than past studies."

Acre per acre, reservoirs emit 25 percent more methane than previously thought, he said.

The researchers acknowledge that reservoirs provide important services like electrical power, flood control, navigation and water. But reservoirs have also altered the dynamics of river ecosystems, impacting fish and other life forms. Only lately have researchers started to look at reservoirs' impact on greenhouse gases.

"While reservoirs are often thought of as 'green' or carbon neutral sources of energy, a growing body of work has documented their role as greenhouse gas sources," Deemer, Harrison and their colleagues write.

Gases from decomposing organic matter

Unlike natural water bodies, reservoirs tend to have flooded large amounts of organic matter that produce carbon dioxide, methane and nitrous oxide as they decompose. Reservoirs also receive a lot of organic matter and "nutrients" like nitrogen and phosphorous from upstream rivers, which can further stimulate greenhouse gas production

In 2000, BioScience published one of the first papers to assert that reservoir greenhouse gases contribute substantially to global warming. Since then, there has been a nine-fold increase in studies of reservoirs and greenhouse gases. Where earlier studies tended to be confined to reservoirs behind power stations, the newer studies also looked at reservoirs used for flood control, water storage, navigation and irrigation.

The WSU researchers are the first to consider methane bubbling in models of reservoir greenhouse gas emissions. Also, while previous papers have found that young, tropical reservoirs emit more methane than older, more northern systems, this study finds that the total global warming effect of a reservoir is best predicted by how biologically productive it is, with more algae and nutrient rich systems producing more methane.

The authors also report higher per-area rates of methane emission from reservoirs than have been reported previously. This means that acre-for-acre the net effect of new reservoirs on atmospheric greenhouse gases will be greater than previously thought. Reservoir construction around the globe is expected to proceed rapidly in coming decades.

Largest study of reservoir greenhouse gas emissions

"There's been a growing sense in the literature that methane bubbles are a really important component of the total emissions from lake and reservoir ecosystems," said Deemer. "This study revisited the literature to try and synthesize what we know about the magnitude and control on methane emissions and other greenhouse gases—carbon dioxide and nitrous oxide."

The result is that, in addition to being the largest study of reservoir to date, it is the first to comprehensively look at the flow of all three major greenhouse gases—carbon dioxide, methane and nitrous oxide—from reservoirs to the atmosphere.

The work is in keeping with WSU's Grand Challenges, a suite of research initiatives aimed at large societal issues. It is particularly relevant to the challenge of sustainable resources and its themes of supplying food, energy and water for future generations.

Funding sources include the U.S. Army Corps of Engineers Climate Preparedness and Resilience Programs, the National Science Foundation and the U.S. Environmental Protection Agency. None of the funders had a role in the design of the research or the interpretation of its results.

Explore further: A new global warming culprit: Dam drawdowns

More information: bioscience.oxfordjournals.org/lookup/doi/10.1093/biosci/biw117

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Shootist
1.8 / 5 (19) Sep 30, 2016
When will it be warm enough to grow wheat and raise dairy cattle on the island of Greenland? Add 400 years to that date and you'll find that the Medieval Climate Optimum was a good time for humans and other growing things.
Oriondestiny
1.6 / 5 (14) Sep 30, 2016
I really think these IPCC people have it all backwards. The warming is causing more CO2 and methane, not the other way around. Longer summers will make for more growth, farther north, more plant matter to die, rot, and release CO2 and methane. But again, another article blaming human beings for what is nothing more than natural variation. This claim of 80% of the warming being caused by methane is obviously unprovable as the IPCC's many other claims. Another thing. A few degrees average swing up or down over a century is not climate changing by any means. It's the same ole spring, summer, fall and winter with the same ole variable unpredictabe weather where I live as there has always been. Nothing has changed. I honestly wish it was warming.
Crucialitis
3.7 / 5 (9) Sep 30, 2016
Oriondestiny, do you have a specific argument against methane being produced from decomposition due to flooding for reservoirs, as mentioned in the article?
TogetherinParis
1 / 5 (7) Oct 01, 2016
Reservoirs are a small but important addition to the buffer between us and global warming because of water's capacity to absorb and reflect heat.
greenonions
5 / 5 (7) Oct 01, 2016
Nothing has changed. I honestly wish it was warming.
So data means nothing to you? We just broke 16 months of heat records - in a row. http://phys.org/n...nth.html USDA plant zones are moving north - http://www.npr.or...ng-north Spring is coming earlier than it used to - http://www.climat...-earlier The data says otherwise - http://www.global...y-data-0 But you really wish it was warming.........
rrrander
1.7 / 5 (11) Oct 01, 2016
Hmmmm. Reservoirs for people so they have water and increased growing seasons in the north thanks to rising temps. Gee, that sounds terrible.
antialias_physorg
5 / 5 (7) Oct 01, 2016
When will it be warm enough to grow wheat and raise dairy cattle on the island of Greenland?

At exactly that time when droughts and rain variability induced by climate change will make argriculture nearly impossible everywhere else (i.e. when all the people from asia, africa and india will start piling into your back yard because they can't feed themselves at home)
antigoracle
1.3 / 5 (13) Oct 01, 2016
Nothing has changed. I honestly wish it was warming.
So data means nothing to you? We just broke 16 months of heat records - in a row. http://phys.org/n...nth.html But you really wish it was warming.........
-- onion retard
The onion jackass brays. Tell us jackass, what the data meant to you, when you went on that 2 day, 1200 mile, CO2 spewing jaunt, in which you emitted over a tenth of the US annual average.
harb123
1 / 5 (6) Oct 01, 2016
canada has lotsa new reservoirs since 60's. they also have nuke power that uses regular u235 and can convert spent usa nuc material since they use heavy water to cool.
but people and farms need the dams and power can be made or the dams can be refilled for water or power storage as needed
bring back the auburn dam and others as it was a good concept killed for ngr.
the water pumped back up can hit the reservoir to swirl out the stagnent growth ea night.
MR166
1.8 / 5 (10) Oct 01, 2016
Yea, drain all the reservoirs. Yea, drain all of the swamps for that matter. End the horror of hydro-electric power. Academia, they very group that should be insuring our future is busy selling hand tailored research to the highest bidder instead of doing useful work.

It is this counter productive squandering of our educated minds that will soon lead to financial disaster and the real Armageddon.
TheGhostofOtto1923
2.7 / 5 (7) Oct 01, 2016
Huh. Yet another big factor not included in climate models.

And I thought this stuff was all figured out.
optical
Oct 01, 2016
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optical
Oct 01, 2016
This comment has been removed by a moderator.
ab3a
4 / 5 (4) Oct 01, 2016
I wonder if there is some way to capture that methane and use it for energy?
ExIowan
1 / 5 (5) Oct 01, 2016
I don't understand the issue. When plants grow, they absorb carbon, when they die, they release carbon (and some methane). If you could have an ecosystem that had no plants, then CO2 and no methane production as a result of plant decomposition would be zero.. Problem solved!
We are told that marshes (with lots of algae) are essential parts of ecosystems, yet are not those same marshes just as prolific in their production of methane and CO2 as reservoirs? And if the reservoirs did not catch the water, might not those same plants, decomposing matter and fertilizer runoff just go into the oceans and create the same problem there?
Someone tell me where I'm wrong.
billykiller5050
3.4 / 5 (5) Oct 01, 2016
Right exlowan; get rid of those plants and that pesky oxygen with them.
guyjohn123
2.2 / 5 (5) Oct 01, 2016
In reality, the earth's greenhouse effect is a good thing. If not for the greenhouse effect, earth's average surface temperature would be -18°C (Celsius), or -40°F (Fahrenheit). Instead, our planet exists at a livable 15°C, or 59°F.

In spite of the enormous transfer of The Sun's energy infused into the Earth atmosphere each 24 hours, the Earth maintains a constant temperature because, as a whole, there is no net gain or loss. The Earth receives 164 Watts per square meter over a 24 hour day , So the entire planet receives 84(84000000000000)Terrawatts of Power each 24 hours.
subdolphin
1.7 / 5 (6) Oct 01, 2016
Just a matter of time before living humans and any system that supports the lives of humans are identified as "problems" that need to be corrected.
ExIowan
2 / 5 (3) Oct 01, 2016
Question: Is the heat generated by oxidation significant?

The earth radiates a lot of heat into space, but doesn't the heat released during combustion/oxidation raise the temperature of the atmosphere slightly? There is a lot of heat coming from the world's radiators, tailpipes, smokestacks and fires. I never see that heat mentioned when people are complaining about global warming. Is the amount of heat released too small to be of consequence, or not?
Zzzzzzzz
3.7 / 5 (6) Oct 01, 2016
The article says that 80% of warming caused by reservoirs is from the methane that they release. Deniers cannot comprehend what they read. A delusional existence exacts a price.
Zzzzzzzz
3.7 / 5 (6) Oct 01, 2016
Exlowan - the warming is caused by atmospheric change that increases the atomshere's ability to hold heat, not the generation of heat. I think the first sentence of your earlier post above is quite accurate - you don't understand the issue. Unless of course you are among those whos ability to understand is pre-empted by their delusions. There are plenty of those around.
Zzzzzzzz
3 / 5 (4) Oct 01, 2016
This claim of 80% of the warming being caused by methane is obviously unprovable as the IPCC's many other claims
It just means, that the burning of fossil fuels contributes only with some 20% to global warming - and I'm quite comfortable with such conclusion.
I really think these IPCC people have it all backwards. The warming is causing more CO2 and methane, not the other way around. Longer summers will make for more growth, farther north, more plant matter to die, rot, and release CO2 and methane.
Nope, this is exactly what follows from the above study. The carbon dioxide concentrations follows the global temperatures evolution, it does not advances it. On the contrary, the IPCC people finally got it right... ;-)

No, it means that the warming contribution of reservoirs has an 80% methane cause component.
MR166
1.8 / 5 (5) Oct 01, 2016
"The article says that 80% of warming caused by reservoirs is from the methane that they release. Deniers cannot comprehend what they read. A delusional existence exacts a price."

We have had dams and hydro-electric for how many years? And, how warm is it now? How many people would die with out these dams? Does Zzzzz stand for someone who is really that much asleep?
tblakely1357
2.3 / 5 (3) Oct 01, 2016
For Gaia's sake let's reduce the human population by 95% (in an environmentally sensitive fashion of course), ban technology and mandate a return to a hunter/gatherer lifestyle. Or just to be on the safe side let's just exterminate humanity.
ExIowan
3.3 / 5 (7) Oct 01, 2016
I certainly understand the chemistry of greenhouse gasses and how the shorter wavelengh IR makes it to the earth from the sun and the longer wavelength IR radiated from the earth gets reflected by C02, methane et. al. contributing to global warming.

According to Wikipedia, the total solar insolation is about 90-130 terawatts, while the total energy needs by humans is about 18 terawatts (which means they are releasing this amount of heat). I realize that to be accurate, both would need to be converted to TeraWatt Hours, but you get the idea. Virtually all energy consumed on earth gets converted to heat sooner or later.

My point is that an awful lot of heat is being produced by burning fossil fuels, and by low-temperature oxidation of nearly everything else on earth. It would seem that all this extra heat is significant - even in the face of C02, methane and other greenhouse gasses. If it isn't significant, OK, but I'm thinking it just might be.
TrollBane
3.7 / 5 (3) Oct 02, 2016
Exlowan, It might be locally significant, with a secondary effect on greenhouse gas emissions. Consider the urban heat island effect plus idling engines, hot exhausts and such in cities, which causes more demand for air conditioning, which demands more electricity, which may come from dirty sources. I'm not saying it's a huge effect, but it isn't a completely silly idea and the question is a reasonable one.
thingumbobesquire
1 / 5 (3) Oct 02, 2016
Gauss' Higher Arithmetic and the Mythology of Climate Change http://thingumbob...ogy.html
tscati
5 / 5 (4) Oct 02, 2016
Really the article doesn't say that this is a good or a bad thing, and no-one suggests that reservoirs should be emptied. It's just quantifying one factor in the whole complex system, so that models can be made that are a bit more accurate.
mbee1
5 / 5 (2) Oct 03, 2016
It would be nice if the article at least brought up the subject reservoirs are on water sources like rivers so all those decomposing things in the reservoirs will be there in the rivers and give off methane gas as well. It would seem to me you have to subtract that release before you can claim reservoirs are a new source or at least imply that. NASA measured CO2 warming effect and found it to be 0.080F expressed as 2/10ths of a watt per square meter. I am pretty sure that means we will not get much heating ever from CO2 as that heating is 340 times less than NASA estimates from changes in earths tilt and orbit for the next 25000 years.
hightreason
2 / 5 (4) Oct 03, 2016
Perhaps we just have to get rid of dams, along with over 90% of humans to reduce the greenhouse gas emissions which may or may not make a major difference on temperatures/climate. Unless we are to get rid of dams and humans, we can not be fully green.
Perhaps it is time to step back, take a very deep breath and consider the lunacy of demonising dams to fulfil the green apocalyptic fantasy. Take note, claims that the "science is settled" and "the debate is over" are NOT proof of what was always a far-fetched hypothesis (that a less than 50% increase in the atmospheric concentration of a minor trace gas - .04% is the chief driver of climate/temperature for the entire planet, capable of destroying the planet through uncontrollable warming, defying normal feedback mechanisms. )
Time to wake up-we have been deceived. If we continue swallowing the climate rubbish, we , as a species will choke and probably die.
MR166
2.3 / 5 (6) Oct 03, 2016
The real fact is that ANY human influence on the planet is frowned upon by the green movement.

This influence must be negated regardless of how many lives are lost in the process!
Windchaser
2.7 / 5 (7) Oct 03, 2016
Nope, this is exactly what follows from the above study. The carbon dioxide concentrations follows the global temperatures evolution, it does not advances it.


This requires that we throw out about a century of known physics. Not just the relationship governing CO2's dissolution in water, which tells us that the warming we've seen would not cause anywhere this much CO2 increase, but it also requires that we reject CO2's role as a greenhouse gas, which is a foundational part of our understanding of climate. And that science dates back to the 1800s.

I mean, plus we humans have dug up and burned about 2x as much carbon than what we see in the atmospheric increase. And the isotopic pattern matches that it's fossil fuel carbon. Etc., etc.

No, humans are responsible for the increase in atmospheric CO2, and since CO2 is a greenhouse gas, this has caused warming.
Windchaser
2.6 / 5 (5) Oct 03, 2016
Question: Is the heat generated by oxidation significant?

The earth radiates a lot of heat into space, but doesn't the heat released during combustion/oxidation raise the temperature of the atmosphere slightly? There is a lot of heat coming from the world's radiators, tailpipes, smokestacks and fires. I never see that heat mentioned when people are complaining about global warming. Is the amount of heat released too small to be of consequence, or not?


In this context, yeah. There's roughly 10,000x as much energy from sunlight hitting the Earth as we use from fossil fuels.

So if the Earth is keeping just 1% of more of the energy from sunlight, that's still about 100x as much energy as we produce from fossil fuels.
Windchaser
2 / 5 (4) Oct 03, 2016
According to Wikipedia, the total solar insolation is about 90-130 terawatts, while the total energy needs by humans is about 18 terawatts (which means they are releasing this amount of heat). I realize that to be accurate, both would need to be converted to TeraWatt Hours, but you get the idea. Virtually all energy consumed on earth gets converted to heat sooner or later.


"The Earth receives 174,000 terawatts (TW) of incoming solar radiation (insolation) at the upper atmosphere."
https://en.wikipe...r_energy

...maybe you compared the *hourly* energy from the Sun with the *annual* energy from fossil fuels? 12-18 terawatt-hours would be about right for the hourly solar energy hitting the surface.
ExIowan
2 / 5 (4) Oct 03, 2016
After working through the numbers, I realize that the problem is with Wikipedia - they incorrectly equate Watts and Watt-Hours, something that too many do. Hmm. maybe we need a new term for Watt-Hours to help end the confusion.
It would appear that the total heat released by burning fossil fuels is, in fact, much smaller than I originally thought, and is less than 1% of the total solar insolation.
MR166
2.5 / 5 (6) Oct 03, 2016
Exlowan the problem is that the green movement claims that the earth is a finely balanced instrument and that ANY extraneous input from man is enough to tip the ecology of the earth into an unrecoverable downward spiral. Only ceding our rights and freedoms to those in charge can save us from this Armageddon.
leetennant
5 / 5 (4) Oct 03, 2016
Exlowan the problem is that the green movement claims that the earth is a finely balanced instrument and that ANY extraneous input from man is enough to tip the ecology of the earth into an unrecoverable downward spiral. Only ceding our rights and freedoms to those in charge can save us from this Armageddon.


Boy you like your strawman, don't you? I love how you refer to doubling the amount of GHG in our atmosphere and increasing global temperatures between 4-7 degrees (when 4 is human extinction) as though it's some sort of minor byproduct. The Earth's global ecosystem has an incredible capacity to absorb human impacts. Otherwise we'd already be fucked.

I just don't understand how anyone could be so deluded at this stage of the game. You are paying attention, aren't you? Because shit is going down right now. And if we hit 2 degrees by 2050 then we have 1 billion refugees to contend with. One. Billion. Wake up.
Mike_Massen
2 / 5 (4) Oct 04, 2016
FWIW. Its not understood one bit by the physics lazy agw denier lobby re radiative transfer.

Thats the IR absorbed/emitted from greenhouse gases is Exactly the same as if the sun increased its energy output by a whopping 1.5 Watts/sq meter - this is a constant flux which amounts to a massive
amount of heat exactly like turning up the suns energy control for more visible light !

As ExIowan correctly observed & I restate/clarify for deniers. Sol's energy output that affects earth is mostly visible light (VL) when it hits earth's surface some small amount absorbed by plants to produce proteins/carbs/lignin/cellulose etc

Bulk converted to Infra Red (IR) by the oceans with remaining on land. Greenhouse gases absorb/re-emit IR not just as is but, also added to from collisions re greater atmospheric energy, unfortunately IR also evaporates water adding a +ve feedback. Also N2O is even worse than CO2 eg ~290 times.

We've been lucky with oceans with high specific heat

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