Trolltunga, Troll's tongue rock above lake Ringedalsvatnet, Norway

Fjords Emit as much Methane as All the Deep Oceans Globally

Peer-Reviewed Publication


Waves beating

During heavy storms, the normally stratified layers of water in ocean fjords get mixed, which leads to oxygenation of the fjord floor. But these storm events also result in a spike in methane emissions from fjords to the atmosphere.

Researchers from the University of Gothenburg have estimated that the total emissions of this climate-warming gas are as great from fjords as from all the deep ocean areas in the world put together.

The world’s fjords were created when the inland ice receded, and are a relatively rare natural feature, constituting only 0.13 per cent of all the oceans on Earth. However, according to researchers from the University of Gothenburg, emissions of methane from the surface of fjords are comparable to the emissions of this gas from global deep oceans which account for 84 per cent of the global sea surface area. These results were presented in an article in the prestigious science journal Limnology and Oceanography Letters.

“It’s been known for some time that many fjords have anoxic environments closest to the bottom and that methane forms in the bottom sediment. Usually, only a small portion of this gas ever reaches the atmosphere because it gets broken down as it ascends through the more oxygen-rich waters closer to the surface. But in our research, we recorded large emissions of methane when the water in the fjord was mixed during storm events, for example,” says Stefano Bonaglia, researcher in marine geochemistry at the Department of Marine Sciences at the University of Gothenburg.

Anoxic environments produce methane

Detecting and budgeting methane emissions to the atmosphere is essential to be able to model the future climate. Researchers estimate that methane emissions cause about 30 per cent of the greenhouse effect. The contribution of the oceans to methane emissions is budgeted as significantly smaller than from land areas. But human activity has increased eutrophication in coastal areas, and this has created larger areas of anoxic waters on the sea floor. This is particularly apparent in fjords, and although they constitute only 0.13 per cent of the global sea surface area, they account for about half of all methane emissions to the atmosphere.

“This is because in fjords, carbon-rich sediment is deposited from marine plants and animals as well as from materials entering the fjords from the surrounding land via streams that flow into them. As fjords are relatively protected from ocean currents, the water tends to remain stratified in layers at different temperatures and with different concentrations of salt and oxygen. The layers closest to the fjord floor are anoxic regions where methane gas forms as the material in the sediment decomposes,” says Stefano Bonaglia.

Agriculture drives eutrophication

The researchers from the University of Gothenburg studied By Fjord near Uddevalla during the period 2009–2021 and conducted field studies to measure methane production in the fjord. By Fjord is hypoxic and affected by eutrophication. The Bäve River flows into the fjord, bringing with it high concentrations of nutrients from agriculture in the region. It was clear that during mixing events in the fjord, emissions of methane to the atmosphere rose. During these events, anoxic water from the bottom is lifted rapidly to the surface, taking the methane with it, which can then be emitted into the atmosphere.

1 million tonnes methane

“The methane emissions were high, and American researchers have seen the same types of events in fjords in Canada. We estimate that emissions from all the world’s fjords are of the same magnitude – around 1 Teragram (Tg) or 1 million tonnes per year – as the budgeted emissions from global deep oceans. This is because the distance from the bottom to the surface of a fjord is much shorter than in deep oceans. This results in more organic matter being deposited in the sediment, and not enough time for the methane to be broken down on its way up to the surface,” says Stefano Bonaglia, and adds that if climate change leads to more extreme weather events, methane emissions may rise, but only up to a certain point.

“If we were to see a sharp rise in the number of heavy storm events, methane emissions would be reduced, because the anoxic environments at the bottom of fjords would disappear if the water are mixed frequently.”

Article: High methane emissions from an anoxic fjord driven by mixing and oxygenation

Contact details: Stefan Bonaglia, Associate Senior Lecturer in marine chemistry at the Department of Marine Sciences at the University of Gothenburg. Telephone: +46(0) 737-41 24 97, E-mail


Limnology and Oceanography Letters




Observational study


Not applicable


High methane emissions from an anoxic fjord driven by mixing and oxygenation



From EurekAlert!

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May 30, 2022 2:04 pm

Okay… who farted?

(It’s the fjords wot dunnit, you say? Oh, suuuuure… Whatever you say. Fjords… yeah, that’s the ticket… fjiords… yeah…)

Reply to  H.R.
May 30, 2022 2:33 pm

Whale, you would be surprised to learn.
Whale-watching is undoubtedly one of the most interesting and fantastic outdoor activities, says Norway tourist office.
The most commonly spotted whales in Norway are sperm whales, orcas (killer whales), and humpback whales, but you may very well see other species.
Forget your common garden cow or sheep, have you any ideas how large are these methane exuding devils ?

Reply to  Vuk
May 30, 2022 4:51 pm

Well, Vuk, I used to be a Fjiord man but last year I bought a RAM.

Clyde Spencer
Reply to  H.R.
May 30, 2022 8:04 pm

You are just trying to Dodge answering his question.

Reply to  Clyde Spencer
May 31, 2022 4:25 am

Oh, my, now _I’m_ pining for the Fjords!

Reply to  Vuk
May 31, 2022 4:29 am

Captain: “Phones, what was that? It sounded like an underwater A-10!”
Sonarman: “No, sir. Just a whale, Sir.”

Reply to  Joe
May 31, 2022 9:57 am


Reply to  Vuk
May 31, 2022 9:56 am

Old joke warning: What is the difference between a cocktail lounge an elephant’s fart?
One is a barroom.
The other is a “Barroom!”.
Huge whales are something else again.
Methane–oh the horror.

Reply to  Vuk
May 31, 2022 11:47 pm

Q: What is the climate connection between whales, oil, beef, and fishing/fisheries?
A: “Whale Oil Beef Hooked!”

Reply to  H.R.
May 31, 2022 4:22 am

The dead-parrot-sketch somehow springs to mind. “I wish to make a complaint!”

Tom Halla
May 30, 2022 2:05 pm

As if methane matters?

Reply to  Tom Halla
May 31, 2022 4:26 am

All the cattle on Earth could be abducted by aliens tomorrow, and Earth would still be happily generating methane, FWIW.

May 30, 2022 2:09 pm

Dam the fiords and pump all the water out.

Reply to  Opus
May 30, 2022 3:11 pm

I would nuke them

Reply to  Pauleta
May 30, 2022 3:31 pm

Thanks, Pauleta, that made me laugh.


Reply to  Opus
May 30, 2022 9:52 pm

No, No, No, fill the Fjords in, there is pleanty of hills and mountains surrounding the Fjords. And with all the hydro power in Norway battery powered earth moving equipment could be used.

Trying to Play Nice
Reply to  Opus
May 31, 2022 4:56 am

I guess Canada and the Scandinavian countries aren’t going to meed their Paris targets.

May 30, 2022 2:19 pm

Send the bill to the Norway Sovereign Wealth Fund.

Government Pension Fund of Norway – Wikipedia

Pete Bonk
May 30, 2022 2:20 pm

On can imagine long ago, a fjord undisturbed for millennia, being riled up by a storm, CH4 released in a mad rush, and a well timed lightning bolt igniting the mix; with the resulting chaos and drama. There’s a Norse legend for ya, by Odin!!

Rud Istvan
May 30, 2022 2:34 pm

This new paper omits a BIG fact.

It is true that methane is a potent GHG in the laboratory, when measured by itself in dry air. About 64x more potent than CO2.

But is is NOT true that CH4 has any GHE in the real world where atmospheric water vapor averages about 2% (range near zero to over 4%). That is because methane IR absorption bands are completely overlapped by the much more abundant water vapor absorption bands.

So the beautiful Norwegian fjords have no climate impact whatsoever, no matter how stormy fjord weather might get in the future with dreaded climate change. And I am pretty sure Norwegians won’t stop producing their oil and natgas because of this new paper—despite its erroneous methane fear mongering.

Reply to  Rud Istvan
May 30, 2022 3:24 pm

Whack-a-mole continues.


I agree that methane is a small player, but not for the reasons you stated. The first thing you need to understand is that gases that nearly saturate absorption in a short distance result in the last absorption and emission (to space) to occur at very high altitude. It is the effective average altitude of emission to space that sets the energy balance and thus temperature at that (average) effective altitude, and also via the lapse rate, govern the greenhouse effect. However, as the atmosphere cools with increasing altitude (from the lapse rate), almost all of the water vapor condenses out, first as clouds at moderate altitudes, and most of the remainder as ice crystals at higher altitudes. The CO2 and methane are not condensed out at the temperatures encountered. Thus the relative fraction of water vapor to CO2 and methane decreases sharply as you approach the TOA, where the action is very important. This is the reason that CO2 and methane have a very large effect at small concentrations. However, due to their small concentrations, the effect is not totally dominate.

Curious George
Reply to  Loydo
May 30, 2022 4:19 pm

The standard atmosphere has a temperature of 15 oC at the surface, a lapse rate of 6.5 oC km–1 from 0 km to 11 km, a zero lapse rate from 11 km to 20 km, and a lapse rate of –1 oC km–1 from 20 km to 32 km in the stratosphere (i.e., temperature increases with height).

Boff Doff
Reply to  Loydo
May 30, 2022 4:20 pm

Any chance you could quantify the warming at the TOA and how it impacts temperatures at the surface?

Reply to  Loydo
May 30, 2022 4:37 pm

So, the incoming IR from the sun is a different enough spectrum from the outgoing IR from earth at night?….resulting in a larger amount of IR atmospheric warming at night than the warming that CO2 and CH4 prevent during the day?

Reply to  Anti_griff
May 31, 2022 1:46 am

I always wondered about that! Even if the solar light has a peak in the yellow, it still seems that it produces much more IR than that re-emitted by the Earth.

Reply to  Loydo
May 30, 2022 7:48 pm

“decreases sharply as you approach the TOA, where the action is very important”

Yep, it allows the outward radiation , ie atmospheric cooling , to be more effective.

Reply to  Loydo
May 31, 2022 1:43 am

How can the co2 and methane at the top of the atmosphere be important if water vapour has already absorbed and remitted the heat from the ground so many times that there is no ir left by the time it reaches the upper atmosphere? Isn’t that what is meant by a particular band being saturated? No increase in water vapour or other ghg would have any effect, right?

William Wilson
Reply to  Rud Istvan
May 31, 2022 2:58 am

The 64x more potent thing is for the artificial constraint of releasing equal amounts of methane and carbon dioxide into the atmosphere. It can be shown that the mass of CO2 in the atmosphere is about 3300 billion tonnes. Similarly the mass of methane is about 5.5 billion tonnes. So release equal masses of two gases which are present in a ratio of about 600:1 and which is going to show the bigger effect? Time these guys were called out on their GWPs. You are totally correct about the ir stuff. Methane is not a threat to global temps. These guys are lying or ignorant or stupid.

Sweet Old Bob
May 30, 2022 2:34 pm

“Researchers estimate that methane emissions cause about 30 per cent of the greenhouse effect”


Oh , ignoring water vapor ….again.

Reply to  Sweet Old Bob
May 30, 2022 3:13 pm

I was thinking water vapor accounted for at 80% of our wonderfully useful greenhouse effect. Are they trying to account for to 150 – 200% of the gases responsible? Ove inflating methane’s importance is a good way to do it.

Clyde Spencer
Reply to  Sweet Old Bob
May 30, 2022 8:15 pm

It seems that the COP26 meeting resolved to do something about the methane leaking from oil and gas wells. Even though almost all methane is natural, it makes it look like methane leakage is another evil resulting from the use of fossil fuels, and it gives the impression that they are doing something to address global warming/climate change, whatever.

Reply to  Clyde Spencer
May 31, 2022 1:48 am

Almost all CO2 is natural too, so the IPCC is definitely sticking with the playbook.

Steve Case
Reply to  Sweet Old Bob
May 31, 2022 12:13 am

Exactly the fact free assertion I copied out to comment on.

Roy W Spencer
May 30, 2022 2:52 pm

….Nessie fart jokes in 3, 2, 1…

ray g
May 30, 2022 3:20 pm

Silly me, but if methane is a gas wouldnt it just rise to the top without the storms.
Like farting in the bath,no storm needed.

Curious George
Reply to  ray g
May 30, 2022 4:11 pm

It stays at the bottom as a methane hydrate, also known as a methane ice.

Mike Smith
May 30, 2022 4:07 pm

I blame Slartibartfast.

Clyde Spencer
Reply to  Mike Smith
May 30, 2022 8:17 pm

If he had had his way, there would be more fjords. Job security!

H. D. Hoese
May 30, 2022 4:14 pm

I have seen gas bubbling up in a Louisiana marsh, quite associated with high organic production. Citation of the first two authors, Breitburg and Boesch is interesting, two biologists with a background of exceptional credible work that I know a lot about. Boesch especially led the development of a process to reduce nitrogen in the Mississippi River, became an activist about nutrients, nitrogen of which was called “demonized” in 2002 by a now deceased student (Scott Nixon) of the process in many places. Like carbon dioxide, river nitrogen is still called the driver, which is clearly now shown to be stratification, important as a complicated and still poorly understood amplifier. The not so “dead zone” off the river is press certified as a dying process in the Gulf of Mexico, but the fisheries didn’t know it. Models until recently were 2 dimensional in their analysis, fish didn’t know that either.

There is nothing new about this, L. V.Worthington, 1954. A preliminary note on the time scale in North Atlantic circulation. Deep Sea Research. 1(4):244-251, showed evidence of a reduction, with a suggestion that oxygen formation required a “catastrophic” process. It is difficult to believe that we have enough data, especially since sampling in the last few decades has been biased toward looking for low oxygen.
Nixon, S. W. and B. A. Buckley. 2002. “A strikingly rich zone”–Nutrient enrichment and secondary production in coastal marine ecosystems. Estuaries. 25(4b):782-796.

From the paper—“Ebullition accounts for 0–84% of methane fluxes in shallow tidal systems (Borges and Abril 2011), but no ebullition data are available for fjords.” Hmmm! ”

Bill Parsons
Reply to  H. D. Hoese
May 30, 2022 5:44 pm

There’s two references to “fish” in this thread as of 6:30 pm mst. Your post has both of them. But I’ll bet that the north atlantic, “fjord-dwelling” fish around Norway are well-adapted to this condition and may even require it. I offer this unencumbered by any actual knowledge, but I think the global warmers should be reminded of aquatic life before they do something stupid to save the rest of the planet.

Reply to  Bill Parsons
May 31, 2022 1:53 am

“but I think the global warmers should be reminded of aquatic life before they do something stupid to save the rest of the planet.”

I wish I could upvote you 100x for that comment – warmunists seem to always want to jump on the next band wagon, to be seen saving the environment, and are very reckless about the damage they do.

William Wilson
Reply to  H. D. Hoese
May 31, 2022 3:03 am

Yup, which is why methane was known as marsh gas.

May 30, 2022 4:18 pm

Methane in the deeper oceans of the world is being held as methane hydrates due to the cold temp and pressure……also held in the tundra.

Frank S.
May 30, 2022 4:48 pm

Greta Thunberg’s from Sweden. Sounds like the little lady is “blame shifting”.

Bruce Cobb
Reply to  Frank S.
May 31, 2022 5:12 am

Turns out she can also “see methane”.

May 30, 2022 6:22 pm

A new market for Norway, bagging methane.

Peta of Newark
May 30, 2022 6:32 pm

Yet more garbled rubbish..
As usual, blame the farmers. Hang on, what significant amount of farming is there in Norway apart from tree farming.i.e. Forestry
If Norway didn’t have its offshore oil and onshore forests, Norway would be nothing, a complete zero.
At which point we might recall how the UK beat itself up about Acid Rain, coming off UK coal burning power stations some 20 and 30 years ago.
Sorry no, the acid in Scandinavian rivers and lakes was coming from Scandinavian foresters draining ancient peat bogs, marshes and swamps so as to be able to get their trees in and out, baby trees in, grown up trees out.

Apart from the very acidic water that came off that process, so did vast amounts of organic material that would have settled out in the fjords,
Large amounts will still be there and while the forestry continues, so will the flow of organic material feeding the hypoxic fjord floors

Next storms.
So what. A storm in a fjord would be the equivalent of a disease outbreak running through a population of critters.
Yes, during the outbreak, many more critters will die than normally would – same with the storm = more Methane will be released.

But when the disease outbreak abates, less critters will be dying – the pox/bacteria/virus took out ‘the easy ones’
Same with the storm. It will take out the easy to remove Methane but when the storm abates methane output will fall.
So over a long time span, the total number of critters that died will be the same and also the total methane output will be the same.
Storms don’t make extra methane (to release) any more than viruses make extra people (to kill)

It gets worse…
Going back many millions of years, dinosaur times for example, earth’s land surface would have been covered with very dense forest – that forest would have had immense stores of organic material in the soils underneath it.
We know that, its where oil, coal gas came from.

That is not the case now, 38% of all land surface is inorganic sandy desert. (50 yrs ago it was 33%, that’s ‘never better’ progress for ya)
33% is frozen ice and the rest is used for intensive agriculture (growing sugar mostly) and soon will be = sandy desert.
Thus Norway’s forests releasing all the organic material (and thus Methane) they do are typical of how the entire world was, or should be if us humans hadn’t chopped all the trees.

A globe covered in forest, as it was, represents an immense amount of Methane release – the entire ocean would have been producing methane at the rate Norwegian fjords now are.

So if methane is such a potent climate destroying force, how come we are all here now discussing it?

May 30, 2022 8:58 pm

It seems, surprisingly, NOAA has figured out a solution to this problem.
What is eutrophication?Harmful algal blooms, dead zones, and fish kills are the results of a process called eutrophication—which begins with the increased load of nutrients to estuaries and coastal waters.

After the usual homage to the CAGW gods, they continue,

…In recent years, NOAA’s National Centers for Coastal Ocean Science (NCCOS), in collaboration with NOAA’s Northeast Fisheries Science Center, has enlisted estuaries’ indigenous residents, namely, bivalve mollusks, to help slow and, in some cases, reverse the process of eutrophication, since they efficiently remove nutrients from the water as they feed on phytoplankton and detritus.
A groundbreaking modeling project in Long Island Sound showed that the oyster aquaculture industry in Connecticut provides $8.5 – $23 million annually in nutrient reduction benefits. The project also showed that reasonable expansion of oyster aquaculture could provide as much nutrient reduction as the comparable investment of $470 million in traditional nutrient-reduction measures, such as wastewater treatment improvements and agricultural best management practices.
The NOAA scientists used aquaculture modeling tools to demonstrate that shellfish aquaculture compares favorably to existing nutrient management strategies in terms of efficiency of nutrient removal and implementation cost. Documenting the water quality benefits provided by shellfish aquaculture has increased both communities’ and regulators’ acceptance of shellfish farming, not only in Connecticut but across the nation. In Chesapeake Bay, for example, nutrient removal policies include the harvesting of oyster tissue as an approved method, and in Mashpee Bay, Massachusetts, cultivation and harvest of oysters and clams are part of the official nutrient management plan.

Bjarne Bisballe
May 30, 2022 10:03 pm

In one day atmospere breakes down 1,60 Megatons of methane, while 1,65 Megatons are emitted, so 0,05 Megatons are accumulated every day (0,07 ppm in a year). Methane is a 85 times more potent greenhouse gas than CO2 (mass/mass) so 0,05 Megatons are as potent as 4,5 Megaton CO2. The accumulation of CO2 in one day is 50 Megaton (2,3 ppm in a year). Methane influence is then less than 10 percent of CO2.

Steve Case
Reply to  Bjarne Bisballe
May 31, 2022 12:49 am

The question to ask is how much will methane run up global temperature by say 2100? The so-called mainstream media doesn’t ask and most certainly NEVER says how much global temperature increase will methane cause.

By the end of the century it’s less than 0.01°C. Does that comport with less than 10% of CO2?

Reply to  Bjarne Bisballe
May 31, 2022 1:59 am

Whoa you can’t go talking math to climate scientists, it’s racist!

Just stick to feelings and signalling, like the IPCC.

gary pate
May 30, 2022 11:31 pm

It’s worse than we thought!!!! Give us more money to study it more.

May 31, 2022 1:35 am

Does this mean that methane can be classed as a renewable energy source? Seems like it’s production from decaying life in the sea never ends.

Bruce Cobb
May 31, 2022 4:29 am

A little-known fact is that the Great Norwegian Blue Parrot thrives on that methane, which is one reason why one should never take them away, and why if you do, they tend to die from Pining for the Fjords Syndrome (PFS). Of course, one could always get a dog, and hang up lots of pictures of the fjords, but it’s not quite the same, is it. They will still tend to be sad and sickly.

May 31, 2022 4:52 am

I nominare University of Gothenburg for the annual “Rent Seekers Award.”

Bob Smith
May 31, 2022 8:58 am

A few comments…

  • Note the end of the article…

“…says Stefano Bonaglia, and adds that if climate change leads to more extreme weather events, methane emissions may rise, but only up to a certain point.“

If we were to see a sharp rise in the number of heavy storm events, methane emissions would be reduced, because the anoxic environments at the bottom of fjords would disappear if the water are mixed frequently.”

The article states that this methane emission is effectively a non-issue. Peak fjord methane emission is limited by the fact that storm mixing of the fjord water will remove the source of methane generation.

  • Is the comparison between ocean and fjord methane emission based on storm mixing in the fjord or is it averaged over a year?
  • In the referenced paper, the standard error for the average global methane emission is on the same order as the average global emission
michael hart
May 31, 2022 1:00 pm

About the only thing I believe about methane emissions (other than release from long stored deposits) is that the well-understood processes at the base of the food chain pyramid must necessarily be far greater than that from occasional belching ruminants.

May 31, 2022 3:43 pm

“I grow old … I grow old …I shall wear the bottoms of my trousers rolled.
Shall I part my hair behind? Do I dare to eat a peach?I shall wear white flannel trousers, and walk upon the beach.I have heard the mermaids farting, each at each.
I hope to heck they will not fart at me…

May 31, 2022 10:09 pm

So the climate botherers can go ahead and ban fjords now. Ban Norway.

May 31, 2022 11:23 pm

I blame Slartibartfast.

Last edited 11 months ago by druid144
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