Louisiana wetlands struggling with sea-level rise four times the global average

Louisiana wetlands struggling with sea-level rise 4 times the global average
A swamp-to-marsh transition near Houma, Louisiana shows dead trees that are most likely the result of saltwater intrusion. Credit: Torbjorn Tornqvist

Without major efforts to rebuild Louisiana's wetlands, particularly in the westernmost part of the state, there is little chance that the coast will be able to withstand the accelerating rate of sea-level rise, a new Tulane University study concludes.

The study by researchers in Tulane's Department of Earth and Environmental Sciences and published in the open-access journal Nature Communications shows that the rate of in the region over the past six to 10 years amounts to half an inch per year on average.

"In the Mississippi Delta, about 65 percent of study sites are probably still keeping pace, but in the westernmost part of coastal Louisiana, more than 60 percent of sites are on track to drown," said Tulane geology professor Torbjörn E. Törnqvist, a co-author of the study.

Törnqvist conducted the research with lead author and PhD candidate Krista L. Jankowski and co-author Anjali M. Fernandes, a former postdoc in Törnqvist's group who is now at the University of Connecticut.

The researchers used an unconventional method to measure that integrated information from different data sources. They analyzed measurements of shallow subsidence rates at 274 sites across the coast and combined these with published GPS-measurements of deeper subsidence rates. Adding published satellite observations of the of the sea surface in the Gulf of Mexico, they were able to calculate how rapidly sea level is rising with respect to the coastal wetland surface.

"The bottom line is that in order to assess how dire the situation is in Louisiana, this new dataset is a huge step forward compared to anything we've done before," Törnqvist said.

Justin Lawrence of the National Science Foundation, which provided funding for the study, agreed.

"These researchers have developed a new method of evaluating whether coastal marshes in Louisiana will be submerged by rising sea levels," Lawrence said. "The findings suggest that a large portion of coastal marshes in Louisiana are vulnerable to present-day sea-level rise. This work may provide an early indication of what is to occur in coastal regions around the world later this century."


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Rising Sea Greater Danger to Louisiana than Sinking Land

More information: Nature Communications, DOI: 10.1038/NCOMMS14792
Journal information: Nature Communications

Provided by Tulane University
Citation: Louisiana wetlands struggling with sea-level rise four times the global average (2017, March 14) retrieved 22 May 2019 from https://phys.org/news/2017-03-louisiana-wetlands-struggling-sea-level-global.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
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Mar 14, 2017
Nonsense;
they are measuring APPARENT sea level, not actual; the whole area is subsiding so yes the area will drown.
"they were able to calculate how rapidly sea level is rising with respect to the coastal wetland surface"

Many reasons for subsidence…mainly oil & water extraction.

Mar 14, 2017
Luke 21:25
"There will be signs in the sun and moon and stars, and on the earth dismay among the nations, bewildered by the roaring of the sea and the surging of the waves.
26 Men will faint from fear and anxiety over what is coming upon the earth..."

Seems like it's going to be rising a lot sooner and a lot faster than anticipated. The scientists will once again be very surprised and baffled at the speed, intensity and severity at which these things happen.

Mar 14, 2017
"26 Men will faint from fear and anxiety over what is coming upon the earth..."

Well that is easy to believe. Just mention CO2 and most college students become ill.

Mar 14, 2017
BTW could the headline be more misleading? When I was a child we used to laugh at Pravda and the state controlled propaganda that they published. Little did I know then that our media and science community would soon be doing the same thing.

Mar 14, 2017
Well it looks like from the comments that Global Warming denial is alive and well in the US. They deserve to go under the soonest. They're the largest polluters and with "the Donald" in office, it's only going to get worse. You guys deserve everything you get. The crappy part is that we all live on the same planet so with the US denial and the Chinese attitude of "we have to catch up", we will all perish sooner than you think. A great parallel most can relate too is "we're all peeing in the pool" and don't care, the water will stay clean enough.

Mar 14, 2017
Louisiana voted for polluters.

South Carolina did too, and their subsidence is also high.

Irony.


Mar 14, 2017
"The study by researchers in Tulane's Department of Earth and Environmental Sciences and published in the open-access journal Nature Communications shows that the rate of sea-level rise in the region over the past six to 10 years amounts to half an inch per year on average."

Exactly what part of that quote is not propaganda?

It is physically impossible for one area to have a sea level rise of 5 inches and not the whole world.

Mar 14, 2017
When I was a child we used to laugh at Pravda and the state controlled propaganda that they published. Little did I know then that our media and science community would soon be doing the same thing.

In another thread you claimed that: -
100s of billions of your and my money are being diverted to people like Al Gore and big corporations.

and
Our universities are willing co-conspirators to this misuse of public funds. People need to be indited and jailed for this scheme!

Propaganda?

Why is it that some people think that they can make any outlandish accusations they want and not be expected to provide evidence?

Mar 14, 2017
"Exactly what part of that quote is not propaganda?"
------------------------------------

The part which is measurement.

Mar 14, 2017
"Why is it that some people think that they can make any outlandish accusations they want and not be expected to provide evidence?"

Steve, how can one part of a coastline have a sea level that is 5 inches higher than the rest of the coast. Now if they were claiming that increased flow from the Mississippi was creating the higher levels that would be reasonable. To infer that this increase is due to sea level change is disingenuous. As I said, this is pure unadulterated propaganda.

Mar 14, 2017
Here you go Steve, https://phys.org/...ara.html

Have some more propaganda.

The scientific community should be ashamed of itself!

Mar 14, 2017
"The scientific community should be ashamed of itself!"
----------------------------------------

There won't be one, if the Trumpistas and Putin have their way. They are quickly dismantling the foundations of our government and society.

Maybe they think they are creating inland shoreline in Louisiana.

The loss of the EPA would be a real blow to civilization, I think.

Mar 14, 2017
Time to invest in future shorefronts!

Mar 14, 2017
"The loss of the EPA would be a real blow to civilization, I think."

Well they brought it on themselves by over regulating. If a little is good a lot is not necessarily better.

They will not be eliminated since they do serve a valuable purpose but their powers will be more limited. For instance, regulating CO2 emissions on the grounds that it is a "Pollutant" and then refusing to show scientific proof of the reasoning behind the regulations is just a giant political power grab.

Mar 14, 2017
Why do you keep on impugning the motives of professional scientists?

Are you in politics? Religion? Sales?

Mar 14, 2017
Here you go Steve, https://phys.org/...ara.html

Have some more propaganda.

The scientific community should be ashamed of itself!


More accusations and still no evidence. To paraphrase somebody else, you are FAKE news.

https://www.googl...r?&*

Mar 14, 2017
Why do you keep on impugning the motives of professional scientists?

Are you in politics? Religion? Sales?
Why do you keep pretending to be one?

Mar 14, 2017
Get over your fixation on me.

I did not ever say I was a scientist. And I never held a position called such.

Outgrow it.

Mar 14, 2017
Fake News Alert!!!

there is little chance that the coast will be able to withstand the accelerating rate of sea-level rise

Nowhere in the study do the authors make a claim about an "accelerating rate of sea-level rise". In fact, in their Supplementary Data 1 table they show sea level rise as 2 mm per year and acknowledge that:
the mean rate of sea-level rise in the Gulf of Mexico appears to have remained below the global mean over the past few decades

However, due to widely varying rates of land subsidence and uplift the surface elevation changes measured as much as -41 and +46 mm per year. That's to be expected from a wide river delta inundated with marshes.

The tide gauge records in that area show no acceleration in sea level rise, which is consistent with global sea level rise data. See, for example, here:

https://tidesandc...=8771450

and global rate here:

http://sealevel.colorado.edu/

Mar 14, 2017
I did not ever say I was a scientist
"Environmental managers play a scientific and administrative role in an organization."

-Oh but wait...

"It is required for them to have a bachelor's degree... A bachelor's degree is required in a field such as environmental science."

-So I guess youre right. Youre not a scientist just like youre not an engineer.

One thing to keep in mind...

"Environmental managers are responsible for making sure an organization is compliant with environmental regulations in areas such as air quality, waste, clean water, and pollution."

-And since we know youre ignorant of such things as CFR regs and stack emissions opacity and the def of volatile solids, we know it takes more than writing a popsci article on cow farm design to make you one.

Dug
Mar 15, 2017
Any article that does not cogently and clearly separate the two problems it attempts to address, but rather marries them as one - in this case "subsidence" and "sea level rise" - is suspect regarding its agenda, intent and scientific competence. It in fact only reduces the ability to recognize and or determine the seriousness of either problem.

Mar 15, 2017
Nonsense;
...
Many reasons for subsidence…mainly oil & water extraction.


Any article that does not cogently and clearly separate the two problems it attempts to address, but rather marries them as one - in this case "subsidence" and "sea level rise" - is suspect regarding its agenda

And where exactly does the article (or the original paper) say anything about the reasons for this sea level rise? Hint: Nowhere.

So before you claim 'nonsense' about a statement or claim it has an agenda make sure someone is even making that statement. Otherwise you're the one talking nonsense and pushing an agenda.

Mar 15, 2017
"And where exactly does the article (or the original paper) say anything about the reasons for this sea level rise? Hint: Nowhere."

That statement implies that you believe that the "Sea Level" has increased by 5 inches during the last 10 years in that area. Can you explain why this rise is not reflected in the entire Gulf of Mexico?

Mar 15, 2017
Can you explain why this rise is not reflected in the entire Gulf of Mexico?
@MR
before you go any further... did you know that the tides can be very different dependent upon where you are in a state, let alone some area as large as the Gulf of Mexico?

gravity is only part of the equation for tides... there are three separate bodies involved (Sun, Earth, Moon), there is rotation of the earth and there is terrain, or currents, or...

so all of that affect the amplitude and time, because there are times where tides happen more than once a day (semi-diurnal)

now, taking that into consideration... now can you see why the sea level can rise with a global average but not seem to rise locally?

i am hoping you are going to check facts and actually do some homework, hence my refusal to give links this time... plus, it's tiring b/c you are so literate in science but only when it's something other than climate science - which you have no capacity for logic

Mar 15, 2017
Capt. I really doubt that gravity has changed all the much in 10 years. I really don't think that changes in the amplitude of the tides qualifies as sea level change.

Mar 16, 2017
Capt. I really doubt that gravity has changed all the much in 10 years
@MR
wasn't the point
was i being too subtle?
point is: you're literate in science and even try to learn about stuff, but you completely refuse to accept the exact same level, or even better levels of validated science in climate science

and that doesn't strike you as being odd in any way?
i mean... do you really think there is some global conspiracy?
hells bells man, people can't agree on the tastiness of bacon between cultures and you think they somehow came together to get rich on AGW?

& if that is the case, why are the only people making sh*t tons of $$ the ones who are anti-AGW?

think about it for a moment...

i aint asking you to believe everything... only validated science
from source material - not articles even
no scaremongering... just studies man. studies!
and not even singular studies!
validated studies!
things we can say "we know that", like Lacis et al...

Mar 16, 2017
and you think they somehow came together to get rich on AGW?

Which, for some reason, I'm not seeing anyone actually accomplishing. Least of all scientists who are on a fixed salary. So they couldn't care less - from a salary point of view - if climate chage was real or not.
(Note also that being a scientists is something you definitely don't do for the salary. With much less effort you can rake in a lot more in the industry. Heck, I'm currently getting pay-raises that are almost as large as the entire salary I was getting when I was a scientists)

Mar 16, 2017
Science is easily corruptible by popular opinion. There is funding to be had by being politically correct. As an example look how many papers were written on the benefits of the low fat diet when in truth fats and oils should be the main source of calories and high glycemic index carbs should not be eaten at all.

Mar 16, 2017
I will admit that my opinions are based on articles like this and not the original papers. Thus the biases in the choice of words and the presentation of the findings could be those of the author of the article and not the findings the scientists producing the articles. If this is the case then the scientific press must be taken to task.

Mar 16, 2017
You see English is a very precise language and sometimes the choice of words is the difference between propaganda and true science.

Oops I meant to say "and not the findings of the scientists producing the papers".

Mar 16, 2017
Look at all the papers that were written about the demise of the polar bears. In reality they are doing just fine and populations are growing significantly. I think that the motives of "Researchers" like this need to be questioned when their findings are that wrong.

Mar 16, 2017
What is going to happen when you realize you are wrong?

Mar 16, 2017
"What is going to happen when you realize you are wrong?"

Well I hope that I will be man enough to admit it. Oops, is that hate speech? Are we allowed to use gender specific words anymore?

Mar 16, 2017
Science is easily corruptible by popular opinion.

No. Because if you follow popular opinion instead of the scientific method then you're risking your career (which you spent at least 10 years to build).
This would be dumb. Scientists - at least the overwhelming majority - aren't dumb. Your findings must be reproducible and pass peer review. 'Opinion' holds no stake in peer review - nor in science in general.
Moreover: in peer review you don't know who reviews your stuff (so you couldn't even collude with a reviewer - let alone 3 or 4 - if you wanted to)

There are hot topics in science for which there is more funding (As it should be. Research of matters of intense interest should be funded). But even if you fail to nab a grant - that doesn't change your salary.

To put it plainly: Getting a billion dollars or zero dollars grant changes your salary by zero cent. All you get are more toys to play with (and more PhD students....basically the same thing)

Mar 16, 2017
rs. In reality they are doing just fine and populations are growing significantly

You will find that anyone who claims this is basing their numbers on anecdotal evidence from the 50's. Not any kind of study that would pass even semi-serious scrutiny.
If the habitat disappears the species will disappear (or at the very least will be in trouble). There's no rocket science level thinking needed to understand this.

In the end polar bears aren't the issue because human survival is not dependent on polar bear survival. Polar bears were chosen because they are easy to see. The stuff that will cause real trouble for human survival (low availabity of fish due to increasing dead zones because warm water cannot retain as much oxygen as cold water) is not easy to see.

Uneducated people need to be given things they can see.

There's no amount of "infotainment" thet will make them understand what a deadzone is and how it will affect their avaiability of food.

Mar 16, 2017
Science is easily corruptible by popular opinion.

And then, of course, there are scientists who actually look at the data and check whether it's biased by opinion.
https://phys.org/...ate.html
Turns out it's not.

Is that going to change your opinion?
(Note the word 'opinion' which you hate so much. The hypocrisy would be thick as anything if it didn't).

Mar 16, 2017
Science is easily corruptible by popular opinion
@MR
no, it isn't - science fiction is.
I will admit that my opinions are based on articles like this and not the original papers
this is true - for AGW and for diets
If this is the case then the scientific press must be taken to task
why? they studied communication, or english, or journalism, not science (typically)
the problem (in articles) is the influence of "popular opinion" as you put it... which in turn causes bias due to ignorance or political/religious affiliation

so if you get your science from source material, you will understand... but so long as you get your material from articles you will never get the full story, even if you read it on a science site
You see English is a very precise language
no, it really isn't. it can be, especially when you use a specialised lexicon, but in general it's very imprecise

i mean, english borrows from everyone - that isn't precision

2Bcont'd

Mar 16, 2017
@mr cont'd
Look at all the papers that were written about the demise of the polar bears
1- when you say papers, are you talking articles or studies, because a study is supported by evidence whereas an article isn't

2- what about the studies regarding polar bears? do you have some factual evidence based arguments against them?
that should be published in a journal, not on some biased political site sans peer review, don't you think?
In reality they are doing just fine and populations are growing significantly. I think that the motives of "Researchers" like this need to be questioned when their findings are that wrong
1- prove it wrong

2- don't forget to differentiate between local populations and whole populations
remember, the population of a breeding farm of rare birds is not the same thing as the total global population of the same bird

and that is where you're making your mistake WRT bears... see AA_P post above


Mar 16, 2017
"Your findings must be reproducible and pass peer review. 'Opinion' holds no stake in peer review - nor in science in general. "

Exactly what is reproducible in the computer climate models? So far AGW has morphed into climate change and every event is non-falsifiable.

Mar 16, 2017
The climate models are used as proof of an eventual outcome but their failures are never recognized. The government's historical temperature data is highly suspect due to "Adjustments". This data is used to prove the correctness of the models. The whole system reeks of political influence.

Mar 16, 2017
Exactly what is reproducible in the computer climate models?
@MR
the exact same thing as what is reproducible in physics models
So far AGW has morphed into climate change and every event is non-falsifiable
blatantly false claim due to ignorance of science
ALL science is falsifiable - if it aint then it aint science, it's religion... kinda like your political arguments above

here's the thing: if you can prove something, then do so, with evidence that is equivalent to the scientific method

don't keep making the same tired debunked claims you always make RE: AGW just because you want to believe them to be true
The climate models are used as proof of an eventual outcome but their failures are never recognized
blatant double false claim
1- climate models make a prediction of probabilities
2- you can't make a prediction of probabilities without stating the likelihood of the event, which means there has to be evolution of data (IOW - mistakes)

Mar 16, 2017
@mr cont'd
The government's historical temperature data is highly suspect due to "Adjustments"
epic false claim yet again
no, the adjustments are due to reasons - and those reasons were spelled out in a 9th grade reading level to you, specifically, more than once

Not only that but i linked the studies that gave the justifications for said adjustments

you can't have it both ways - you complain because it was adjusted due to known issues
you complain because no one is adjusting data due to known issues

are you just looking to complain because you don't like it or are you wanting to follow the evidence?
(don't answer - you've already demonstrated the former)
The whole system reeks of political influence
then prove it and become Trumps next cabinet appointment and rich beyond your wildest dreams - because that is what the deniers have been trying to prove from the beginning

no one has ever succeeded

ever

because science isn't about belief

Mar 16, 2017
https://tidesandc...ends.htm

Look I don't know what the original paper claimed but the article is ludicrous! Unless the papers author/s were misquoted he/she et all have seriously tried to mislead the public by claiming a fictitious sea level rise. Now why would the do that other than for political reasons?

Mar 16, 2017
https://tidesandc...=8764311

OK I don't know everything!!! It seems that coastal LA does have a 10MM/year sea level change vs 2 or so MM/year for the rest of the Atlantic and most of the Gulf of Mexico. How this could be possible is beyond my knowledge but I stand corrected. I am assuming here that land subsidence is being excluded from this measurement.

Mar 16, 2017
I have to believe subsidence is involved.

Mar 16, 2017
Looking at the charts it seems that during the last 100 years the sea level of Eugene Island has risen .7 meters more than the sea level of Pensacola Florida. The 2 are seperated by only 400 miles. How is that physically possible?!?! Both rates of increase appear to be quite linear.

Mar 16, 2017
Gkam if that were true then the correct term would be sea depth not sea level. I cannot believe that NOAA would confuse the two.

Mar 16, 2017
I have to believe subsidence is involved.


That is part of it, but not the big part of it. It has more to do with the loss of wetlands and barrier islands. The wetlands go because of saltwater encroachment because of the canals and channels being cut for the gas wells and pipelines.

The barrier islands have always moved around for hundreds of millions of years, the problem is caused by the couyons who think they can make them stay in one place by dredging up sand (cutting channels in the sea floor that wreaks havoc on the barrier islands and the wetlands) and "replenishing" the islands that are just going to keep doing what they always done,, move.

One other thing adds to it too. The levees that keep certain places dry? To do that they have to add water to the other side of the levee,,,, rocket surgery, eh?

Mar 16, 2017
Uncle Ira I do not see how the existence or non-existence of inland channels can affect the sea level near Eugene Island.

Mar 17, 2017
Uncle Ira I do not see how the existence or non-existence of inland channels can affect the sea level near Eugene Island.

remember what i was saying about tides above? (MAR 15)
well check this out from your NOAA link
https://tidesandc...ymap.htm

please note that just because we don't understand why [x] happens doesn't mean we won't even know, so don't assume this means anything special or that it falsifies anything


Mar 17, 2017
Capt., in reality I am just asking what the real scientific definition of sea level change is. Does this measurement include subsidence in any manner?

Mar 17, 2017
Now if this difference in sea level between the two points were due to say a change in wind patterns or currents I really doubt that the changes in both locations would be so linear over the past 100 years. AskDad's link to Galveston Tx also showed a very linear graph.

Mar 17, 2017
Uncle Ira I do not see how the existence or non-existence of inland channels can affect the sea level near Eugene Island.


I don't understand that either. That is why I did not say it did. I was talking about the wetlands and barrier islands. Those channels allow salt water infiltration that kills off marsh, and wetlands, which you lose. When you lose that, then the currents can erode more of the shore, which kills more marsh and wetlands, which allows more erosion, which kills off more marsh and wetlands.

Those channels for the pipelines and wells are also pipelines for wetland poisons (salt water). If the wetland foliage is gone, if the marsh is gone, when the swamp foliage is gone there is nothing to hold the ground in place. No shelter from the tides, currents and storms.

And levees are major contributors to the problem too them.

Mar 17, 2017
Wetland destruction:

The Army Corps of Engineers has been at war with the Mississippi for a century. The massive levees it built along the river have helped keep middle America dry. But this war on nature had unintended consequences, choking off the river's natural land-building process. The straitjacketed Mississippi no longer carried as much silt from its banks and its floodplain down to its delta, so it no longer created as many of the coastal wetlands that served as natural hurricane protection for New Orleans. The city was now safe from the river, but dangerously exposed to the gulf; 25 square miles of protective wetlands vanished every year. Since the huge silt infusions that had shored up the city's foundations no longer arrived, New Orleans began to appear to sink.

The whole problem is a loss of land mass to the surrounding area causing Gulf water to encroach on the delta waterways. This is not actually subsidence of the surface area in the delta.


Mar 17, 2017
Capt., in reality I am just asking what the real scientific definition of sea level change is. Does this measurement include subsidence in any manner?
@Mr
it's an increase in global mean sea level ( https://www.merri...%20level )

also- on the NOAA site there is a glossary for terminology - all gov't sites will have this somewhere
https://tidesandc...vel(MSL)

you can also find international definitions - World Meteorological Organization (WMO)

as well as evidence from international sources: https://scholar.g...ea+level

Mar 17, 2017
AskDad's link to Galveston Tx also showed a very linear graph.
@MR
i would ask you to not keep focusing on a singular small point or area for the simple reason that you will not be able to understand what a global mean sea level rise is when you concentrate on the specific levels around Galveston, TX....

that was my point about tides and other stuff above

example from another area: we think the Earth is rugged and full of hills and mountains and deep oceans, but that is because, very specifically, our scale

if you look at the overall changes based upon the percent of change from the Earth as a whole, it's not really all that "rugged"

a relief globe is therefore misleading in that it's exaggerated

the same thing about focusing on TX when the problem is a global one... it is no different than focusing on the temperature in [pick a location] during a single storm on a single year when talking global climate (IOW- the "it's cold outside" defense)

Mar 17, 2017
Capt. I understand your point about a world view but I also like to think that I am capable of understanding a simple chart or data point. Thus when two readings are in direct conflict I want to know if it is my misunderstanding or if it is a problem with the data.

Mar 17, 2017
.. I also like to think that I am capable of understanding a simple chart or data point. Thus when two readings are in direct conflict....
@MR
if you were talking about straightforward numbers, you would have a point b/c you know that comparing 8 people to 7 people means the 8 ppl group has more people

also consider that longer term measurements are going to be a lot more accurate than shorter term measurements (error bars show this and explain it in one graph linked above)

consider also any mitigating factors - this would be the whole "data manipulation argument" you brought up earlier... for instance- measurement twice a day at noon and midnight will show something completely different than measurements at high and low tide

then there is the bias angle- you're looking for a reason to believe [x] over [y]

lastly, what does the science say about it?
https://scholar.google.com/

not watts, but real peer reviewed science - the studies

Mar 17, 2017
Capt. I understand your point about a world view but I also like to think that I am capable of understanding a simple chart or data point. Thus when two readings are in direct conflict I want to know if it is my misunderstanding or if it is a problem with the data.


If I am not miss understanding you. You are asking why the sea level rise would be higher in Louisiana then it is in Texas? You think it should be the same, right?

I did not explain him good enough, I will try again. If you lose wetlands, the marshes and swamp, then there is nothing there to ask like a buffer, a geological shock-absorber, more water gets in during any one tide. It's like nature's seawalls.

Oh yeah, I almost forget. Bennie-Skippy is 100% correct about the levees, in fixing one problem they create another problem.

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