Support the Arctic Sea Ice Forum and Blog

Author Topic: Ocean temperatures  (Read 25154 times)

Hefaistos

  • Guest
Re: Ocean temperatures
« Reply #50 on: August 23, 2020, 12:46:40 AM »
...
So what the hell are you doing bringing this guy as an authoritative source to this forum?


Geron, as I said in my original post 2018, this was percieved to be a Very Important Paper: "This is a really important research paper with enormous policy implications."
It was also picked up a lot in mass media!
It was published in Nature!

Then came Nic Lewis and in essence destroyed their results. It turns out that they didn't do their calculations correctly.
Paper was RETRACTED by Nature.
After retraction came recalculations, and now their results are basically in line with previous research, as there is no statistical significance to their claim that oceans are heating faster. "...after correction, the Resplandy et al. results do not suggest a larger increase in ocean heat content than previously thought"

Geron, do you have anything to say about the science here? About the critical analysis?
Seemingly not, You prefer to just throw your petty pebbles at the messenger, who actually did a great service to the science community here.

Why don't you want to discuss the science?

We should also mention the mass media. That research was big climate news, reported in I'd say all major mass media, here are some examples:
https://www.bbc.co.uk/news/science-environment-46046067
https://www.nytimes.com/2018/10/31/climate/ocean-temperatures-hotter.html https://www.washingtonpost.com/energy-environment/2018/10/31/startling-new-research-finds-large-buildup-heat-oceans-suggesting-faster-rate-global-warming/ https://www.scientificamerican.com/article/the-oceans-are-heating-up-faster-than-expected/ https://edition.cnn.com/2018/11/01/australia/ocean-warming-report-intl/index.html http://www.latimes.com/science/sciencenow/la-sci-sn-oceans-study-climate-change-20181031-story.html
https://www.usatoday.com/story/news/nation-now/2018/11/01/oceans-more-heat-study-global-warming-climate-change-nature/1843074002/
https://www.independent.co.uk/environment/climate-change-global-warming-ocean-temperature-heat-fossil-fuels-science-research-a8612796.html

How many have published the news about the retraction and that results are now in line with previous research?

Hefaistos

  • Guest
Re: Ocean temperatures
« Reply #51 on: August 23, 2020, 12:49:30 AM »
Agreed gerontocrat.
Nic Lewis is well known for hand waving away any research that finds global warming a risk.
Some suggested reading for those so inclined.
 https://andthentheresphysics.wordpress.com/2014/02/01/understanding-lewis-2013/
http://www.realclimate.org/index.php/archives/2016/02/marvel-et-al-2015-part-iii-response-to-nic-lewis/

And who is doing the hand waving here?

Do you have anything to say about the science here?
About the critical analysis?

KiwiGriff

  • Nilas ice
  • Posts: 1614
    • View Profile
  • Liked: 710
  • Likes Given: 372
Re: Ocean temperatures
« Reply #52 on: August 23, 2020, 01:43:32 AM »
I never bother following links to whack fringe sites as it gives them  traffic they dont deserve .
Nic Lewis is not an authority and his blog posts are not science so do not need examination.
I did follow your links to the MSM.
According to you
Quote
How many have published the news about the retraction and that results are now in line with previous research?
From your first two links.
Quote
Errors have been found in a recent study suggesting the oceans were soaking up more heat than previously estimated.

The initial report suggested that the seas have absorbed 60% more than previously thought.

But a re-examination by a mathematician showed that the margin of error was larger than in the published study.

The authors have acknowledged the problem and have submitted a correction to the journal.
https://www.bbc.com/news/science-environment-46046067
Quote
Editors’ Note: November 14, 2018

An earlier version of this article included a conclusion from a study about ocean warming that is now in doubt. The researchers are working to revise their study because of errors detected in their calculations and it appears unlikely that they will be able to support their original conclusion that the oceans have warmed an average of 60 percent more per year than the current official estimates by the Intergovernmental Panel on Climate Change. The sections of the article dealing with that conclusion have been removed and the headline has been updated.

Update: Sept. 26, 2019: Nature, the journal which initially published the study last year, announced on Wednesday that it was retracting the paper.
https://www.nytimes.com/2018/10/31/climate/ocean-temperatures-hotter.html

You have just been publicly Pawned for gibbering nonsense.
I will bet your list came unchecked from some fringe crank site and like many deniers you never bothered to check what your links actually said  instead believed your crank source unconditionally.

Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
Notebooks of Lazarus Long.
Robert Heinlein.

kinbote

  • New ice
  • Posts: 17
    • View Profile
  • Liked: 14
  • Likes Given: 27
Re: Ocean temperatures
« Reply #53 on: August 23, 2020, 03:19:04 AM »
...
Then came Nic Lewis and in essence destroyed their results. It turns out that they didn't do their calculations correctly.
Paper was RETRACTED by Nature.
After retraction came recalculations, and now their results are basically in line with previous research, as there is no statistical significance to their claim that oceans are heating faster. "...after correction, the Resplandy et al. results do not suggest a larger increase in ocean heat content than previously thought"
...
High-profile ocean warming paper to get a correction
https://www.sciencemag.org/news/2018/11/high-profile-ocean-warming-paper-get-correction

The overall conclusion that oceans are trapping more and more heat mirrors other studies and is not inaccurate, but the margin of error in the study is larger than originally thought, said Ralph Keeling, a professor of geosciences at Scripps and co-author of the paper.

"These problems do not invalidate the methodology or the new insights into ocean biogeochemistry on which it is based, but they do influence the mean rate of warming we infer, and more importantly, the uncertainties of that calculation," said Keeling in a statement on RealClimate.org.

"The more important message is that our study lacks the accuracy to narrow the range of previous estimates of ocean uptake," Keeling said in an email. He thanked Lewis for pointing out the anomaly.

In the past, scientific debates about climate science have prompted skeptics to attack mainstream climate science generally. Some climate scientists said they are concerned that could happen again in this case and the outcome wildly misinterpreted.

When asked about the response of skeptics, climate scientist Michael Mann of Pennsylvania State University in State College said, "We can't worry about that."

"We have to just call it as we see it, do good science, put it out there, defend it and, when necessary, correct it. That's the legitimate scientific process, and it stands in stark contrast to the tactics employed by the forces of pseudoscience and antiscience," Mann said.

This morning the website Climate Depot, which frequently targets mainstream climate science, sent out an email with the headline, "Skeptic review dismantles study."


----

Sounds familiar. Also, I'm not sure I understand the argument that Mass Media ignored the retraction and resubmission of this Very Important Paper, particularly when I checked the first three links you shared and all had updates on the retraction, and two had links to updated stories with more information.


Hefaistos

  • Guest
Re: Ocean temperatures
« Reply #54 on: August 23, 2020, 08:20:17 AM »
I never bother following links to whack fringe sites as it gives them  traffic they dont deserve .
Nic Lewis is not an authority and his blog posts are not science so do not need examination.

In this case he is, as it is only due to Nic Lewis' critical review that this Seemingly Very Important Paper got retracted from Nature, one of the leading science journals. On top of that Prof. Keeling himself taking the blame. At least he had the manners to thank Nic Lewis for his help in finding the faults in that research

Quote
I did follow your links to the MSM.

The links were just a sample to show how the results of the paper were widely published. The list was from Nic Lewis site.
In addition, I asked a question, how many of them that published a retraction notice. Yes, some of them did. Some of them certainly didn't.

Quote
You have just been publicly Pawned for gibbering nonsense.
I will bet your list came unchecked from some fringe crank site and like many deniers you never bothered to check what your links actually said  instead believed your crank source unconditionally.

Please, Kiwigriff. We are not in the Forum Decorum sandpit thread now! We are in the Science section, discussing a major scientific paper that has been retracted from a top notch journal due to the researchers not being able to make some rather basic calculations correctly. It's pretty scandalous what has happened, not least due to how widely publicized those results were!

You, however, have totally nothing substantial to say about the issue itself. You say that it is "nonsense". Indeed?
Your major quest seems to be to try to scandalize me for bringing this up.
That's pretty sad.
I think that there should be room for scientific discussions in the Science forum of ASIF?

Finally, you accuse me of being a 'denier'. No, I'm not a 'denier', I'm just a realist. I have my Ph.D. and my critical mind, and I don't believe in climate alarmism any more.

Simon

  • New ice
  • Posts: 56
    • View Profile
  • Liked: 22
  • Likes Given: 192
Re: Ocean temperatures
« Reply #55 on: August 23, 2020, 08:44:21 AM »

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #56 on: August 23, 2020, 09:51:42 AM »
So Lewis is a denier but he did play a role in the retraction of this paper.

I will remove the link to his site from the post above but i will leave the pdf attached.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Hefaistos

  • Guest
Re: Ocean temperatures
« Reply #57 on: August 23, 2020, 01:35:49 PM »
So Lewis is a denier but he did play a role in the retraction of this paper.

I will remove the link to his site from the post above but i will leave the pdf attached.

The inquisitor came up with the verdict, and poor Nic's head is chopped. Why does this make me think about the queen of hearts in the Alice in wonderland fairytale?

Seriously, I don't think it's correct to define Lewis as a 'denier'. He has never denied AGW and the effect of GHG, afaik. He is a skeptic when it comes to how strong the climate feedbacks are, e.g. as measured by the ECS or the TCR, where he claims values are likely in the lower end of the ranges set by IPCC.
E.g. in this youtube talk, where he assigns ECS values somewhere around 1.7. Does that make him a denier?

I find everything he says in that presentation perfectly reasonable, and very interesting.

I don't think it should qualify anyone to be labeled a denier who just disputes the strength of feedbacks, when the discussion is still well within the limits set by the IPCC. At least as long as the IPCC is unable to narrow down the ECS range, and no-one in the science community can be very sure about the correct values.

So, what exactly is it that makes Nic Lewis a 'denier'?

Hefaistos

  • Guest
Re: Ocean temperatures
« Reply #58 on: August 23, 2020, 02:14:40 PM »
....
You can add American Enterprise Institute and and and and..

So what the hell are you doing bringing this guy as an authoritative source to this forum?


While in the Science (!) forum, maybe it should also be mentioned that poor head-chopped Nic also had a paper published in a VERY well renowned climate science journal:

" An Objective Bayesian Improved Approach for Applying Optimal Fingerprint Techniques to Estimate Climate Sensitivity"
Nicholas Lewis
J. Climate (2013) 26 (19): 7414–7429.
https://doi.org/10.1175/JCLI-D-12-00473.1

« Last Edit: August 23, 2020, 02:20:22 PM by Hefaistos »

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #59 on: August 23, 2020, 05:17:11 PM »
So Lewis is a denier but he did play a role in the retraction of this paper.

I will remove the link to his site from the post above but i will leave the pdf attached.
I find everything he says in that presentation perfectly reasonable, and very interesting.

So, what exactly is it that makes Nic Lewis a 'denier'?

His link to the Global Warming Policy Foundation.

The YT talk is questioning if going zero carbon by 2050 is needed.

His general career.

Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Neven

  • Administrator
  • First-year ice
  • Posts: 9470
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 1333
  • Likes Given: 617
Re: Ocean temperatures
« Reply #60 on: August 23, 2020, 06:13:26 PM »
Nic Lewis is a climate risk denier. There is no doubt about it. He believes there are no serious risks to global warming. He's not stupid, though.

Hefaistos is not a climate risk denier. He made his point, but there's absolutely no need to turn Nic Lewis into Galileo.

Does that about sum it up?
The enemy is within
Don't confuse me with him

E. Smith

Tom_Mazanec

  • Guest
Re: Ocean temperatures
« Reply #61 on: August 23, 2020, 07:35:42 PM »
If you say there are no risks to AGW then I guess you are a denier.
On the other hand, I deny Sam Carana's projection of 18° C warming by 2026 and human extinction, but that does not make me a Denier.

KiwiGriff

  • Nilas ice
  • Posts: 1614
    • View Profile
  • Liked: 710
  • Likes Given: 372
Re: Ocean temperatures
« Reply #62 on: August 23, 2020, 08:10:01 PM »
<Snip. Let's not make Hefaistos the centre of attention and stay on-topic; N.>
« Last Edit: August 23, 2020, 08:33:03 PM by Neven »
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
Notebooks of Lazarus Long.
Robert Heinlein.

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #63 on: September 20, 2020, 11:12:43 AM »
Climate change: Earthquake 'hack' reveals scale of ocean warming

Scientists have found a clever new way of measuring ocean warming, using sound waves from undersea earthquakes.

The researchers say the "hack" works because sound travels faster in warmer water.

The team looked at sonic data from the Indian Ocean emitted by tremors over a 10-year period.

As the seas have warmed due to global heating, the scientists have seen the sound waves increase in speed.

Their new method shows the decadal warming trend in the Indian Ocean was far higher than previous estimates.

...

The scientists examined data from over 4,000 tremors that occurred in the Indian Ocean between 2004 and 2016.

...

The team then looked for pairs of "repeaters", earthquakes with almost identical origins and power.

By measuring how long these slow-moving signals took to travel across the waters from Indonesia to a monitoring station on the island of Diego Garcia, they were able to work out the changes in temperature for the whole of the ocean over the 10-year period.

"It takes sound waves about half an hour to travel from Sumatra to Diego Garcia," lead author Dr Wenbo Wu from the California Institute of Technology told BBC News.

"The temperature change of the deep ocean between Sumatra and Diego Garcia causes this half-hour travel time to vary by a few tenths of a second.

"Because we can measure these variations very accurately, we can infer the small changes in the average temperature of the deep ocean, in this case about a tenth of a degree."

...

In their research, the scientists showed that warming in the Indian Ocean over the decade that they studied was greater than previously estimated.

However, the paper has some important caveats.

"It is important to emphasise that this is a result that applies to this particular region and this particular decade," said Dr Wu.

"We need to apply our method in many more regions and over different time frames to evaluate whether there is any systematic under- or over-estimation of the deep-ocean trend globally.

"It is much too early to draw any conclusions in this direction."

https://www.bbc.com/news/science-environment-54193334
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

vox_mundi

  • Multi-year ice
  • Posts: 10153
    • View Profile
  • Liked: 3510
  • Likes Given: 745
Re: Ocean temperatures
« Reply #64 on: September 25, 2020, 06:51:24 PM »
Major Wind-Driven Ocean Currents Are Shifting Toward the Poles
https://phys.org/news/2020-09-major-wind-driven-ocean-currents-shifting.html


"Satellite observational sea surface temperature anomaly during the last five years (2015-2019), reference to the first five years (1982-1986)". Credit: Alfred-Wegener-Institut/Gerrit Lohmann

The severe droughts in the USA and Australia are the first sign that the tropics, and their warm temperatures, are apparently expanding in the wake of climate change. But until now, scientists have been unable to conclusively explain the reasons for this, because they were mostly focusing on atmospheric processes. Now, experts at the AWI have solved the puzzle: the alarming expansion of the tropics is not caused by processes in the atmosphere, but quite simply by warming subtropical ocean.

To date, experts assumed that processes in the atmosphere played a major role—for instance a change in the ozone concentration or the aerosols. It was also thought possible that the natural climate fluctuations that occur every few decades were responsible for the expansion of the tropics. For many years researchers had been looking in the wrong place, so to speak.

"Our simulations show that an enhanced warming over the subtropical ocean in both the Northern and Southern Hemispheres are the main drivers," says Hu Yang, the study's lead author. These subtropical warming patterns are generated by the dynamic of subtropical ocean gyres, measuring several hundreds of kilometers in diameter, which rotate slowly. These currents are especially well-known in the Pacific, because the majority of floating marine litter is concentrated in them. "Because the currents in the region bring together the surface warming water masses particularly intensely, it's easier for the subtropical ocean surface to accumulate warmth than in other regions—and the same applies to plastic," says Lohmann. As a result of this warming of the subtropical ocean, the tropical warm ocean regions are expanding. According to his calculations, this phenomenon is the catalyst for the tropics expanding to the north and south. "Previous researchers had been taking an overly complicated approach to the problem, and assumed it was due to complex changes in the atmosphere. In reality, it's due to a relatively simple mechanism involving ocean currents."

What led the experts to explore this avenue: data on ocean gyres that they happened to come across five years ago—data on ocean temperatures and satellite-based data, freely available on databases. Both sources indicated that the gyres were becoming warmer and more powerful. "That's what led us to believe that they might be a decisive factor in the expansion of the tropics," explains Hu Yang.

The AWI experts were right: their findings perfectly correspond to actual observations and the latest field data on tropical expansion. Just like in reality, their climate model shows that the tropics are now stretching farther to the north and south alike. In the Southern Hemisphere, the effect is even more pronounced, because the ocean takes up more of the overall area there than in the Northern Hemisphere.



Hu Yang et al, Tropical Expansion Driven by Poleward Advancing Midlatitude Meridional Temperature Gradients, Journal of Geophysical Research: Atmospheres (2020)
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JD033158
« Last Edit: September 26, 2020, 08:58:39 AM by vox_mundi »
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

morganism

  • Nilas ice
  • Posts: 1690
    • View Profile
  • Liked: 215
  • Likes Given: 124
Re: Ocean temperatures
« Reply #65 on: October 19, 2020, 01:00:25 AM »
"The SST changes in the mid- and high-latitudes of the northern Hemisphere during the past 10 years have been dramatic. Just a random sample today looking at other moderate (or stronger) #LaNina events, and it is stunning to compare Oct 2010 to 2020."

https://twitter.com/EricBlake12/status/1317578721226784771

oren

  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: Ocean temperatures
« Reply #66 on: October 19, 2020, 05:44:25 AM »
Thanks morganism, just posting the images. 2020 top, 2010 bottom.




kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #67 on: January 13, 2021, 06:08:51 PM »
Upper Ocean Temperatures Hit Record High in 2020

...

The most recent data indicate that the OHC in the upper 2000 m layer of the world’s oceans has increased with a mean rate of 5.7 ± 1.0 ZJ yr−1 for the 1958−2020 period (IAP/CAS) (Fig. 1). There is a more rapid increase in OHC that began ~1980s and has continued unabated since then (Fig. 1). Since 1986, the average annual increase is 9.1 ± 0.3 ZJ yr−1 (1986 to
2020), almost eight times larger than the linear rate from 1958~1985 (1.2 ± 0.6 ZJ yr−1). Further, the uncertainty has decreased as improved instruments (e.g., Argo) and analysis methods have become available (Cheng et al., 2017; Argo,
2020) (Fig. 1). Moreover, each decade has been warmer than its preceding decade.
The 2020 OHC value is higher than the last year’s value, by 20 ± 8.3 ZJ using the IAP/CAS data, and by 1 ± 3.5 ZJ
using NOAA/NCEI. Both are the highest on record (Table 1). Differences between the OHC analyses reflect the uncertainties in the calculation due to method and data coverage. OHC values herein are preliminary and will be augmented by ocean
profile data which are not immediately available at the end of the year (but added later), and by calibration and quality control processes which also occur on longer time scales. Further quantification of the uncertainties in OHC will help to better
specify the confidence in OHC assessment.

...

https://link.springer.com/article/10.1007/s00376-021-0447-x
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Tom_Mazanec

  • Guest
Re: Ocean temperatures
« Reply #68 on: January 20, 2021, 10:41:34 PM »
Climate change pushed ocean temperatures to record high in 2020, study finds
https://www.abc.net.au/news/2021-01-18/ocean-temperatures-reached-record-high-in-2020-study-finds/13062628
Quote
Last year the world's oceans absorbed 20 zettajoules of heat
Higher ocean temperatures can lead to an increase in extreme weather
Seas are warming at twice the global average in Australia's south-east

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #69 on: January 23, 2021, 05:23:00 PM »
Antarctica: The ocean cools at the surface but warms up at depth

Scientists have concluded that the slight cooling observed at the surface of the Southern Ocean hides a rapid and marked warming of the waters, to a depth of up to 800 meters. These results were obtained thanks to unique data acquired over the past 25 years.

...

The study points to major changes around the polar ice cap where temperatures are increasing by 0.04°C per decade, which could have serious consequences for Antarctic ice. Warm water is also rising rapidly to the surface, at a rate of 39 metres per decade, i.e. between three and ten times more than previously estimated.

Published in Nature Communications on 21 January 2021, these results were obtained thanks to unique data acquired over the past 25 years on board the French Antarctic resupply vessel L'Astrolabe. This is the longest series of temperature records in the Southern Ocean covering north to south.

https://www.sciencedaily.com/releases/2021/01/210121131818.htm

Southern Ocean in-situ temperature trends over 25 years emerge from interannual variability

Abstract
Despite playing a major role in global ocean heat storage, the Southern Ocean remains the most sparsely measured region of the global ocean. Here, a unique 25-year temperature time-series of the upper 800 m, repeated several times a year across the Southern Ocean, allows us to document the long-term change within water-masses and how it compares to the interannual variability. Three regions stand out as having strong trends that dominate over interannual variability: warming of the subantarctic waters (0.29 ± 0.09 °C per decade); cooling of the near-surface subpolar waters (−0.07 ± 0.04 °C per decade); and warming of the subsurface subpolar deep waters (0.04 ± 0.01 °C per decade). Although this subsurface warming of subpolar deep waters is small, it is the most robust long-term trend of our section, being in a region with weak interannual variability. This robust warming is associated with a large shoaling of the maximum temperature core in the subpolar deep water (39 ± 09 m per decade), which has been significantly underestimated by a factor of 3 to 10 in past studies. We find temperature changes of comparable magnitude to those reported in Amundsen–Bellingshausen Seas, which calls for a reconsideration of current ocean changes with important consequences for our understanding of future Antarctic ice-sheet mass loss.

https://www.nature.com/articles/s41467-020-20781-1
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

vox_mundi

  • Multi-year ice
  • Posts: 10153
    • View Profile
  • Liked: 3510
  • Likes Given: 745
Re: Ocean temperatures
« Reply #70 on: March 04, 2021, 11:25:15 PM »
Apparent Atlantic Warming Cycle Likely an Artifact of Climate Forcing
https://phys.org/news/2021-03-apparent-atlantic-artifact-climate.html

Volcanic eruptions, not natural variability, were the cause of an apparent "Atlantic Multidecadal Oscillation," a purported cycle of warming thought to have occurred on a timescale of 40 to 60 years during the pre-industrial era, according to a team of climate scientists who looked at a large array of climate modeling experiments.

The result complements the team's previous finding that what had looked like an "AMO" occurring during the period since industrialization is instead the result of a competition between steady human-caused warming from greenhouse gases and cooling from more time-variable industrial sulphur pollution.

"It is somewhat ironic, I suppose," said Michael E. Mann, distinguished professor of atmospheric science and director, Earth System Science Center, Penn State. "Two decades ago, we brought the AMO into the conversation, arguing that there was a long-term natural, internal climate oscillation centered in the North Atlantic based on the limited observations and simulations that were available then, and coining the term 'AMO.' Many other scientists ran with the concept, but now we've come full circle. My co-authors and I have shown that the AMO is very likely an artifact of climate change driven by human forcing in the modern era and natural forcing in pre-industrial times."

The researchers previously showed that the apparent AMO cycle in the modern era was an artifact of industrialization-driven climate change, specifically the competition between warming over the past century from carbon pollution and an offsetting cooling factor, industrial sulphur pollution, that was strongest from the 1950s through the passage of the Clean Air Acts in the 1970s and 1980s. But they then asked, why do we still see it in pre-industrial records?

Their conclusion, reported today (Mar. 5) in Science, is that the early signal was caused by large volcanic eruptions in past centuries that caused initial cooling and a slow recovery, with an average spacing of just over half a century. The result resembles an irregular, roughly 60-year AMO-like oscillation.

"Some hurricane scientists have claimed that the increase in Atlantic hurricanes in recent decades is due to the uptick of an internal AMO cycle," said Mann. "Our latest study appears to be the final nail in the coffin of that theory. What has in the past been attributed to an internal AMO oscillation is instead the result of external drivers, including human forcing during the industrial era and natural volcanic forcing during the pre-industrial era."

The researchers looked at state-of-the-art climate models both for preindustrial times over the past thousand years where external factors such as solar and volcanic drivers were used, and unforced, "control" simulations where no external drivers were applied and any changes that happen are internally generated. When they looked at simulations for the short, 3- to 7-year El Niño Southern Oscillation (ENSO) cycles, they found that these cycles occurred in the models without adding forcing by climate change, volcanic activity, or anything else.

However, when they looked for the AMO, it did not occur in the unforced model and only appeared in modern times using climate change variables as forcing and in preindustrial times with forcing by volcanic eruptions.

... "What we know is an oscillation like El Niño is real, but the AMO is not."

M.E. Mann el al., "Multidecadal climate oscillations during the past millennium driven by volcanic forcing," Science (2021).
https://science.sciencemag.org/content/371/6533/1014
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

gerontocrat

  • Multi-year ice
  • Posts: 20370
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Ocean temperatures
« Reply #71 on: November 03, 2021, 10:26:04 PM »
Published 28 September 2020, this paywalled paper indicates that stratification of the oceans has increased. This, as time goes by, could have a significant impact on distribution of the increases in heat energy absorbed from Global heating throughout the various depths of the ocean?

https://www.nature.com/articles/s41558-020-00918-2?from=article_link
Increasing ocean stratification over the past half-century
Quote
Abstract
Seawater generally forms stratified layers with lighter waters near the surface and denser waters at greater depth. This stable configuration acts as a barrier to water mixing that impacts the efficiency of vertical exchanges of heat, carbon, oxygen and other constituents.

Previous quantification of stratification change has been limited to simple differencing of surface and 200-m depth changes and has neglected the spatial complexity of ocean density change. Here, we quantify changes in ocean stratification down to depths of 2,000 m using the squared buoyancy frequency N2 and newly available ocean temperature/salinity observations.

We find that stratification globally has increased by a substantial 5.3% [5.0%, 5.8%] in recent decades (1960–2018) (the confidence interval is 5–95%); a rate of 0.90% per decade. Most of the increase (~71%) occurred in the upper 200 m of the ocean and resulted largely (>90%) from temperature changes, although salinity changes play an important role locally.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Juan C. García

  • Young ice
  • Posts: 3359
    • View Profile
  • Liked: 1279
  • Likes Given: 1127
Re: Ocean temperatures
« Reply #72 on: January 12, 2022, 02:16:39 AM »
The Guardian article makes a big noise about ocean heat content (0-2000 metres) rising by 14 zettajoules in 2021. The recent 10 year average is about 11 zettajoules. NOAA has the highest annual gain @ +28 zettajoules (2017) and the lowest at -16 zettajoules (2016)
La Nina & El Nino are big influences.

Note:-A zettajoule is 10^21 joules (i.e. 10 with 21 zeroes after it)

https://www.theguardian.com/environment/2022/jan/11/oceans-hottest-temperatures-research-climate-crisis
Hottest ocean temperatures in history recorded last year

Ocean heating driven by human-caused climate crisis, scientists say, in sixth consecutive year record has been broken

Quote
Last year saw a heat record for the top 2,000 meters of all oceans around the world, despite an ongoing La Niña event, a periodic climatic feature that cools waters in the Pacific. The 2021 record tops a stretch of modern record-keeping that goes back to 1955. The second hottest year for oceans was 2020, while the third hottest was 2019.

As the world warms from the burning of fossil fuels, deforestation and other activities, the oceans have taken the brunt of the extra heat. More than 90% of the heat generated over the past 50 years has been absorbed by the oceans, temporarily helping spare humanity, and other land-based species, from temperatures that would already be catastrophic.

The amount of heat soaked up by the oceans is enormous. Last year, the upper 2,000 meters of the ocean, where most of the warming occurs, absorbed 14 more zettajoules (a unit of electrical energy equal to one sextillion joules) than it did in 2020. This amount of extra energy is 145 times greater than the world’s entire electricity generation which, by comparison, is about half of a zettajoule.

Paper @ https://link.springer.com/content/pdf/10.1007/s00376-022-1461-3.pdf
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #73 on: February 04, 2022, 03:11:53 PM »
Warm ocean temperatures driven by climate change are the new normal

Climate change exposes marine ecosystems to extreme conditions with increasing frequency. More than half of the ocean has experienced extreme heat for the last seven years.

A new study by the Monterey Bay Aquarium reveals that excessively warm ocean temperatures driven by climate change are the new normal. This increases the risk of collapse for crucial marine ecosystems.

For the study, scientists mapped 150 years of sea surface temperatures. They wanted to determine a fixed historical benchmark for marine heat extremes. Scientists then observed how often and how much the ocean surpassed this point. They found:

The year 2014 was the first, in which more than half of the ocean experienced heat extremes.
A similar trend was observed in subsequent years.
In 2019, 57 percent of the ocean experienced heat extreme.
Using this benchmark, scientists confirmed- just two percent of the ocean surface was experiencing extremely warm temperatures at the end of the 19th century.

Dr. Kyle Van Houtan, who headed the research team during his tenure as chief scientist for the aquarium, said, “Climate change is not a future event. The reality is that it’s been affecting us for a while. These dramatic changes we’ve recorded in the ocean are yet another piece of evidence that should be a wake-up call to act on climate change. We are experiencing it now, and it is speeding up.”

... more

https://www.techexplorist.com/warm-ocean-temperatures-driven-climate-change-new-normal/44481/

The recent normalization of historical marine heat extremes

Abstract
Climate change exposes marine ecosystems to extreme conditions with increasing frequency. Capitalizing on the global reconstruction of sea surface temperature (SST) records from 1870-present, we present a centennial-scale index of extreme marine heat within a coherent and comparable statistical framework. A spatially (1° × 1°) and temporally (monthly) resolved index of the normalized historical extreme marine heat events was expressed as a fraction of a year that exceeds a locally determined, monthly varying 98th percentile of SST gradients derived from the first 50 years of climatological records (1870–1919). For the year 2019, our index reports that 57% of the global ocean surface recorded extreme heat, which was comparatively rare (approximately 2%) during the period of the second industrial revolution. Significant increases in the extent of extreme marine events over the past century resulted in many local climates to have shifted out of their historical SST bounds across many economically and ecologically important marine regions. For the global ocean, 2014 was the first year to exceed the 50% threshold of extreme heat thereby becoming “normal”, with the South Atlantic (1998) and Indian (2007) basins crossing this barrier earlier. By focusing on heat extremes, we provide an alternative framework that may help better contextualize the dramatic changes currently occurring in marine systems.

https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0000007
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #74 on: April 21, 2022, 09:47:14 AM »
Global warming is speeding up ocean currents. Here’s why

Excess heat constricts water flow in shallow surface layers


Two years ago, oceanographers made a surprising discovery: Not only have oceans been warming because of human-driven climate change, but the currents that flow through them have accelerated—by some 15% per decade from 1990 to 2013. At the time, many scientists suspected faster ocean winds were driving the speedup. But a new modeling study fingers another culprit: the ocean’s own tendency to warm from top to bottom, leading to constricted surface layers where water flows faster, like blood in clogged arteries. The study suggests climate change will continue to speed up ocean currents, potentially limiting the heat the ocean can capture and complicating migrations for already stressed marine life.

“This mechanism is important,” says Hu Shijian, an oceanographer at the Chinese Academy of Sciences’s Institute of Oceanology, who was the lead author on the 2020 paper. “[The new paper] links directly the surface warming and acceleration of upper ocean circulation.”

Currents like the Atlantic Ocean’s Gulf Stream are highways for marine life, ushers of heat, and drivers of storms. Driven in large part by wind, each of them moves as much water as all the world’s rivers combined. And, despite the fact that the ocean absorbs more than 90% of the heat caused by global warming, until 2020, there had been little evidence that these currents were changing.

When Shang-Ping Xie, a climate scientist at the Scripps Institution of Oceanography, saw Hu’s study, he immediately suspected that the structure of the ocean—not winds—played a leading role in the speedup. He knew the excess warmth from climate change is not distributed evenly through the ocean but is instead concentrated at its surface. This causes surface waters to grow more buoyant—and more reluctant to mix with waters below. The shallower surface layers created by this process have been seen across the world’s oceans.

Xie and his colleagues also realized that, in shallower layers, currents would naturally have to speed up: In effect, the winds were pushing the same amount of water through a narrower pipe. “If you assume the total transport can’t change, your stuff is going to accelerate,” Xie says.

To test that hypothesis, Xie’s team turned to a climate model of all the world’s oceans. The researchers increased either winds, saltiness, or surface temperatures, while holding all other variables steady. Increasing temperatures alone caused currents to speed up more than 77% of the ocean’s surface. That was by far the largest increase, they found in a new study published today in Science Advances. One notable exception was the Gulf Stream, which is likely slowing for an unrelated reason: As Arctic ice melts, it dilutes the sinking, salty water in the North Atlantic that pulls the current northward.

“This is an interesting study with a provocative finding,” says Sarah Gille, a physical oceanographer at Scripps. “We usually assume that if you uniformly warm the ocean, there will be no major impact on ocean circulation.” Accounting for the top-down nature of ocean warming changes that picture, she adds.

The new findings also suggests that in much of the ocean, lower waters, some 400 meters or so down, would slow as warm upper waters take up more and more of the movement, Xie says. Hu is not so certain of that, however. Unpublished measurements of the speed of Argo floats, a fleet of robotic instruments that have been drifting through the ocean for nearly 20 years, show a significant acceleration in surface currents—and a modest increase at lower depths. “I trust what the observations tell us,” Hu says. The new finding, he adds, “might not be the total story.”

But if ocean currents are indeed becoming faster and shallower, there are many implications for the planet. For example, the shallow, speedy currents could ultimately limit how much heat the ocean can absorb, causing more of that excess heat to remain in the atmosphere. Marine microbes and wildlife could be subjected to shallower, hotter, and faster surface waters. And given that the speedup is driven by the steady drumbeat of warming, it means these trends are likely to continue in the future—as long as human emissions of greenhouse gases continue.

https://www.science.org/content/article/global-warming-speeding-ocean-currents-here-s-why

This is a very interesting discovery. 
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

vox_mundi

  • Multi-year ice
  • Posts: 10153
    • View Profile
  • Liked: 3510
  • Likes Given: 745
Re: Ocean temperatures
« Reply #75 on: May 06, 2022, 09:51:51 PM »
World's Ocean Is Losing Its Memory Under Global Warming
https://phys.org/news/2022-05-world-ocean-memory-global.html

Using future projections from the latest generation of Earth System Models, a recent study published in Science Advances found that most of the world's ocean is steadily losing its year-to-year memory under global warming.



Declining ocean memory between the present and the end of the 21st century--blue indicates decline, red indicates increase in memory. Credit: Shi, et al. (2022)

Compared with the fast weather fluctuations of the atmosphere, the slowly varying ocean exhibits strong persistence, or "memory", meaning the ocean temperature tomorrow is likely to look a lot like it does today, with only slight changes. As a result, ocean memory is often used for predicting ocean conditions.

Ocean memory decline is found as a collective response across the climate models to human-induced warming. As greenhouse-gas concentrations continue to rise, such memory decline will become increasingly evident.

"We discovered this phenomenon by examining the similarity in ocean surface temperature from one year to the next as a simple metric for ocean memory," said Hui Shi, lead author and researcher at the Farallon Institute in Petaluma, California. "It's almost as if the ocean is developing amnesia."

Ocean memory is found to be related to the thickness of the uppermost layer of the ocean, known as the mixed layer. Deeper mixed layers have greater heat content, which confers more thermal inertia that translates into memory. However, the mixed layer over most oceans will become shallower in response to continued anthropogenic warming, resulting in a decline in ocean memory.

"Other processes, such as changes in ocean currents and changes in the energy exchange between the atmosphere and ocean, also contribute to changes in ocean memory, but the shoaling of the mixed layer depth and resulting memory decline happens in all regions of the globe, and this makes it an important factor to consider for future climate predictions," said Robert Jnglin Wills, a research scientist at University of Washington in Seattle, Washington, and co-author of the research.



Global averaged ocean memory under different warming scenarios with low to high emissions. Credit: Shi, et al. (2022)

Along with ocean memory decline, the thinning mixed layer is also found to increase the random fluctuations of the sea surface temperature. As a result, although the ocean will not become much more variable from one year to the next in the future, the fraction of helpful signals for prediction largely reduces.

"Reduced ocean memory together with increased random fluctuations suggest intrinsic changes in the system and new challenges in prediction under warming," said Fei-Fei Jin, an atmospheric sciences professor at the University of Hawai'i at Mānoa School of Ocean and Earth Science and Technology, and co-author of the research.

Ocean memory loss doesn't just impact the prediction of physical variables, but could also influence the way we manage sensitive marine ecosystems.

"Reduced memory means less time in advance for a forecast to be made. This could hinder our ability to predict and prepare for ocean change including marine heatwaves, which are known to have caused sudden and pronounced changes in ocean ecosystems around the world," said Michael Jacox, a research scientist at NOAA Fisheries' Southwest Fisheries Science Center in Monterey, California, and co-author of the research.

In fisheries management, the biological parameters used for stock assessment are estimated assuming a stable environment represented by the recent past. Reduced ocean memory might render such estimation inaccurate and calls for new approaches in ecosystem-based fisheries management to include real-time ocean monitoring and other efforts alike. Ocean memory decline also likely exerts impacts on populations of biological resources. Depending on whether the species are adapted to constant or more variable environmental conditions, future changes in their population can be better estimated and predicted by taking ocean memory loss into consideration.

Besides ocean prediction, forecasting land-based impacts on temperature, precipitation as well as extreme events might also be affected by ocean memory decline due to their dependence on the persistence of sea surface temperature as a predictability source. As ocean memory continues to decline, researchers will likely be challenged to search for alternative predictors for skillful predictions.

Hui Shi et al, Global decline in ocean memory over the 21st century, Science Advances (2022).
https://www.science.org/doi/10.1126/sciadv.abm3468
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

vox_mundi

  • Multi-year ice
  • Posts: 10153
    • View Profile
  • Liked: 3510
  • Likes Given: 745
Re: Ocean temperatures
« Reply #76 on: June 21, 2022, 04:40:26 PM »
Systematic Warming Pool Discovered In the Pacific Due to Human Activities
https://phys.org/news/2022-06-systematic-pool-pacific-due-human.html



In a study just released in the journal Communications Earth and Environment, Dr. Armineh Barkhordarian confirms that this systematic warming pool is not the result of natural climatic variations—but of human influences instead.

"This warming pool will continue to increase the water temperature in the future, increasing both the frequency and intensity of local marine heatwaves. The sharp increase in average water temperature is pushing ecosystems to their limits," explains Barkhordarian, an expert on atmospheric science and member of Universität Hamburg's Cluster of Excellence "Climate, Climatic Change, and Society" (CLICCS).

Barkhordarian and her team show how the long-term warming pool has promoted local marine heatwaves in the past. One of these phenomena gained notoriety as the deadly "Pacific Ocean Blob," which had devastating consequences between 2014 and 2015: marine productivity faltered, toxic algal blooms formed, and seabirds and marine mammals died in droves. In addition, the event led to severe droughts on the west coast of the U.S..

The most recent marine heatwave continued for three years, from 2019 to 2021, producing water temperatures up to six degrees Celsius above average. Barkhordarian's team have now proven that increased anthropogenic greenhouse-gas emissions were directly responsible for the extreme event. The probability of such a heatwave arising without human influences is less than one percent; there is a 99-percent probability that increased greenhouse-gas emissions were also required.

In addition, the study shows that the water temperature over the warming pool in the northeast Pacific increased by an average of 0.05 degrees Celsius per year over the past 25 years. Overall, the region cooled less in winter and the summer was 37 days longer on average. As a result, over the past 20 years there have been 31 marine heatwaves in this region alone, compared to just nine between 1982 and 1999.

Armineh Barkhordarian et al, Recent marine heatwaves in the North Pacific warming pool can be attributed to rising atmospheric levels of greenhouse gases, Communications Earth & Environment (2022)





“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

vox_mundi

  • Multi-year ice
  • Posts: 10153
    • View Profile
  • Liked: 3510
  • Likes Given: 745
Re: Ocean temperatures
« Reply #77 on: August 21, 2022, 10:09:12 PM »
Fast-Warming, Ailing Mediterranean Sea May Be a Sign of Things to Come
https://phys.org/news/2022-08-fast-warming-ailing-med-sea.html



From Barcelona to Tel Aviv, scientists say they are witnessing exceptional temperature hikes ranging from 3 degrees Celsius (5.4 Fahrenheit) to 5 degrees Celsius (9 Fahrenheit) above the norm for this time of year. Water temperatures have regularly exceeded 30 C (86 F) on some days.

Extreme heat in Europe and other countries around the Mediterranean has grabbed headlines this summer, but the rising sea temperature is largely out of sight and out of mind.

... About 50 species, including corals, sponges and seaweed, were affected by 'mass mortality effects' (MME) along thousands of kilometers of Mediterranean coasts, according to the study, which was published in the Global Change Biology journal.

Despite representing less than 1% of the global ocean surface area, the Mediterranean is one of the main reservoirs of marine biodiversity, containing between 4% and 18% of the world's known marine species.

Some of the most affected species are key to maintaining the functioning and diversity of the sea's habitats. Species like the Posidonia oceanica seagrass meadows, which can absorb vast amounts of carbon dioxide and shelters marine life, or coral reefs, which are also home to wildlife, would be at risk.

... The situation in the eastern Mediterranean basin is particularly dire.

The waters off Israel, Cyprus, Lebanon and Syria are "the hottest hot spot in the Mediterranean, for sure," said Gil Rilov, a marine biologist at Israel's Oceanographic and Limnological Research institute, and one of the paper's co-authors. Average sea temperatures in the summer are now consistently over 31 C (88 F).

These warming seas are driving many native species to the brink, "because every summer their optimum temperature is being exceeded," he said.

What he and his colleagues are witnessing in terms of biodiversity loss is what is projected to happen further west in the Mediterranean toward Greece, Italy and Spain in the coming years.



Garrabou and Rilov said that policymakers are largely unaware of the warming Mediterranean and its impact.

According to the most recent scientific papers, the sea surface temperature in the Mediterranean has increased by 0.4 C (0.72 F) each decade between 1982 and 2018. On a yearly basis, it has been rising by some 0.05 C (0.09 F) over the past decade without any sign of letting up.

The affected areas have also grown since the 1980s and now covers most of the Mediterranean, the study suggests.

Joaquim Garrabou et al, Marine heatwaves drive recurrent mass mortalities in the Mediterranean Sea, Global Change Biology (2022).
https://onlinelibrary.wiley.com/doi/10.1111/gcb.16301
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

vox_mundi

  • Multi-year ice
  • Posts: 10153
    • View Profile
  • Liked: 3510
  • Likes Given: 745
Re: Ocean temperatures
« Reply #78 on: August 23, 2022, 12:47:46 AM »
Paleoclimatologist Uncovers Ancient Climate Feedback Loop That Accelerated Effects of Earth's Last Warming Episode
https://phys.org/news/2022-08-paleoclimatologist-uncovers-ancient-climate-feedback.html

... One way to assess the role and impact of climatic feedback processes is to use modeling studies to look into the likely future based on what we know now. Climate projection models, for instance, are the tools behind the 1.5° C global warming threshold adopted by the Intergovernmental Panel on Climate Change.

Alternatively, you can look into the past to see what happened at a time when the Earth was up to 1-1.5°C warmer than today. That is what UC Santa Barbara's Syee Weldeab did in a paper published in the Proceedings of the National Academy of Sciences. The professor of paleoclimatology found feedback processes that have concerning implications for our modern, ongoing warming.

To get a paleoclimate perspective on global warming, Weldeab and his colleagues went back some 128,000 to 125,000 years ago to the peak Eemian warm episode. Oceans were up to 1-1.5°C warmer than during the Holocene (our current geological epoch). The authors examined marine sediment from the tropical Atlantic and found exceptionally strong warming of the intermediate water column during a brief interval within the peak Eemian warm episode.

"Remarkably, a substantially diminished Greenland Ice Sheet was capable of producing enough meltwater to perturb the density-driven circulation of the Atlantic Ocean," Weldeab said. "This contributed significantly to the large warming of the intermediate waters we reconstructed."

Typically, warm, salty water travels north from the tropics along the surface of the ocean and cools as it reaches northern mid and high latitudes. At this point, the now colder, denser water drops to the deep sea and travels back down toward the tropics. This interplay of density differences results in the currents that we're familiar with today.

"What happens when you put a large amount of fresh water into the North Atlantic is basically it disturbs ocean circulation and reduces the advection of cold water into the intermediate depth of the tropical Atlantic, and as a result warms the waters at this depth," he said.

While previous studies have discussed the disruption that meltwater caused to currents and temperatures at intermediate depths, the new paper reveals that this warming was "larger than previously thought."

"We show a hitherto undocumented and remarkably large warming of water at intermediate depths, exhibiting a temperature increase of 6.7°C from the average background value," Weldeab said.

This exceptionally strong warming has serious consequences, as the warm water impinges on marine sediment that contains abundant methane hydrates—a mixture of frozen water and methane. These deposits are not far below the surface of the seafloor.

Weldeab explained that at high pressure and low temperatures, the introduction of unusually warm water heats the seafloor sediment, and the ice-encapsulated gases begin to dissolve, releasing methane. Weldeab and colleagues used carbon isotopes (13C/12C) in the shells of microorganisms to uncover the fingerprint of methane release and methane oxidation across the water column.

"This is one of several amplifying climatic feedback processes where a warming climate caused accelerated ice sheet melting,"
he said. "The meltwater weakened the ocean circulation, and as a consequence, the waters at intermediate depth warmed significantly, leading to destabilization of shallow subsurface methane hydrates and release of methane, a potent greenhouse gas."

It is not known for sure whether this feedback cycle will play out in the current round of global warming, though anthropogenic activity has created a higher rate of warming than the one that occurred in the Eemian period.

Syee Weldeab et al, Evidence for massive methane hydrate destabilization during the penultimate interglacial warming, Proceedings of the National Academy of Sciences (2022)
https://www.pnas.org/doi/full/10.1073/pnas.2201871119
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

gerontocrat

  • Multi-year ice
  • Posts: 20370
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Ocean temperatures
« Reply #79 on: October 09, 2022, 05:08:40 PM »
Ocean Heat and AGW

The paper described here may cause some ruffles in the climate science community - not yet peer-reviewed

A draft manuscript submitted to Geophysical Research Letters concludes that ‘ocean heat uptake efficiency’ - the amount of energy transferred into the ocean per degree of global warming - has increased by about 25% from 1970-2021.  This translates roughly into a few years’ delay until global warming temperature targets, such as 2C warming, are exceeded

The paper suggests a 3.5 year delay for AGW to hit +1.5C, and 4.6 years to reach +2C

https://www.essoar.org/pdfjs/10.1002/essoar.10511803.1
Ocean heat uptake efficiency increase since 1970
Quote
B. B. Cael National Oceanography Centre, Southampton, UK.

- Ocean heat uptake has increased from 0.55±0.06 to 0.7±0.02 W/m2K since 1970
- This content has not been peer reviewed.

Abstract

The ocean stores the bulk of excess anthropogenic heat in the Earth system.  The ocean heat uptake efficiency (OHUE) – the flux of heat into the ocean per degree of global warming – is therefore a key factor in how much warming will occur in the coming decades.

In climate models, OHUE is well-characterised, tending to decrease on centennial timescales; in contrast, OHUE is not well-constrained from Earth observations.  Here OHUE and its rate of change are diagnosed from global temperature and ocean heat content records. OHUE increased from 0.57±0.06W/m2K to 0.7±0.02W/m2K over the past five decades. This increase is attributed to steepening heat content gradients in the ocean, and corresponds to ∼4 years’ delay until temperature targets such as 1.5◦C or 2◦C are exceeded.

Plain Language Summary
Human activity causes extra energy to be radiated to Earth’s surface.  Much of this extra energy accumulates in the ocean as heat.  Based on records of global warming and the ocean’s heat content over the past 50 years, here it is shown that the efficiencyof the transfer of this energy into the ocean has increased in recent decades.  This ‘ocean heat uptake efficiency’ is the amount of energy transferred into the ocean per degree of global warming, and has increased by about 25% from 1970-2021.  This translates roughly into a few years’ delay until global warming temperature targets, such as 2◦C warming, are exceeded.

Introduction
Global warming can be understood in terms of conservation of energy of the Earth’s surface.  The amount of warming corresponds to the difference between the extra energy radiated to the Earth’s surface via anthropogenic and natural factors, i.e.  the radiative forcing, versus the amount of that energy that is exported elsewhere (Sellers, 1969). A key reservoir for the export of this excess energy is the ocean, which contains almost all of the anthropogenic excess heat in the Earth system (Cheng et al., 2017; Levitus et al.,312012; Domingues et al., 2008; JMA, 2022; Cheng, 2022; JMA, 2022).  This ocean heat content (OHCH, [ZJ]) has increased by hundreds of zetajoules over the past several decades of sustained ocean observations (Figure 1), during which time Earth’s global mean surface temperature anomaly (T, [K]) has increased by about 1◦C (Figure 1) (Morice et al.,352021; Hersbach et al., 2020; Rohde & Hausfather, 2020; Cowtan & Way, 2014; Hansen36et al., 2006; Lindsey & Dahlman, 2020).

More important than OHC for future climate change is the ocean heat uptake efficiency (OHUE,κ[W/m2K], Materials and Methods (MM)) (Gregory & Mitchell, 1997;, Newsom et al., 2020), that is, how much energy Earth’s surface exports downwards into the ocean per degree of global warming......

...... OHUE is fairly well-characterised within Earth System Models (ESMs).  This is mostly via experiments where atmospheric CO2is increased by 1% per year for 70 years, after which time it has doubled; OHUE can then be defined as the ratio of HandTafter about 70 years, for instance (Gregory & Mitchell, 1997; Kuhlbrodt & Gregory, 2012).  Notably,54–2–ESSOAr | https://doi.org/10.1002/essoar.10511803.1 | CC_BY_4.0 | First posted online: Wed, 6 Jul 2022 03:57:19 | This content has not been peer reviewed.

When these experiments are run for 140 years to the point that that atmospheric CO255quadruples, OHUE almost always decreases between∼70 and∼140 years (Gregory et al., 2015; Watanabe et al., 2013).

In contrast, OHUE is poorly constrained for the real climate system, hindering efforts to validate ESMs’ predictions of climate change in coming decades.  Here a method is presented to diagnose OHUE from observations of ocean heat content and tempera-60ture alone (MM). OHUE has increased from 0.57±0.06 W/m2K to 0.70±0.02 W/m2K61over the past five decades.  This is attributed to the steepening of heat content gradients in the ocean, rather than ocean circulation changes, and corresponds to a few years’ delay in when the temperature targets laid out in the Paris Agreement are exceeded (Adoption of the Paris Agreement FCCC/CP/2015/L.9/Rev.1, 2015)

(Delay in) Years to 1.5 or 2◦C:
To estimate the difference in years taken to surpass 1.5◦C or 2◦C,the transient climate sensitivityTCS=F2×CO2/(λ+κ) is calculated, where F2×CO2∼N(4.0,0.3) W/m2 is the radiative forcing associated with a doubling of CO2 andλ∼N(1.3,0.44) W/m2K is the climate feedback (Sherwood et al., 2020).  Note that the TCS is closely related to the arguably more relevant metric of the transient climate response (Winton et al., 2010); the TCS is preferred in this context, however, as the TCR would require a specification of the surface boundary layer’s heat capacity, a term that is less certain than those that comprise the TCS. The TCS analysis is equivalent to TCR under the plausible assumption that the surface boundary layer’s heat capacity is on the order of 30 ZJ or less, equivalent to roughly the top 10m of the global ocean.  The year of crossing a temperature threshold of Cdegrees is then defined as y= 70C/TCS; 70 is the number of years that is required for atmospheric CO2concentrations to increase at 1% per year until the concentration doubles, which corresponds to a linear increase in radiative forcing under the assumption of logarithmic CO2 forcing (Bloch-Johnson et242al., 2021).  For each (κ1970,δ) pair, a random value of F2×CO2 and λ are sampled from the distributions above, and y is calculated for C= 1.5 and 2◦C, and for κ1970and κ2021=244κ1970(1 + 51δ).   

The difference y(C= 2,κ2021)−y(C= 2,κ1970) is 4.6±1.5 years;
the difference y (C=  1.5,κ2021)−y(C=  1.5,κ1970) is 3.5±1.1 years. 


Note that this is a heuristic metric and is only intended to illustrate the potential impact of the change diagnosed herein.(Morice et al., 2021)248–8–ESSOAr | https://doi.org/10.1002/essoar.10511803.1 | CC_BY_4.0 | First posted online: Wed, 6 Jul 2022 03:57:19 | This content has not been peer reviewed.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #80 on: October 09, 2022, 11:03:03 PM »
Quote
‘ocean heat uptake efficiency’ - the amount of energy transferred into the ocean per degree of global warming - has increased by about 25% from 1970-2021
Interesting metric. Of course that will happen when you push a climate to a warmer climate via a warming atmosphere. I would not mind the delays although they are tiny.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

FishOutofWater

  • Nilas ice
  • Posts: 1088
    • View Profile
  • Liked: 696
  • Likes Given: 332
Re: Ocean temperatures
« Reply #81 on: October 10, 2022, 02:12:26 AM »
The peak intensities of storms over the ocean are increasing. The strongest hurricanes are getting stronger and rapid intensification of cyclones is increasing the danger. Increasing ocean heat uptake efficiency has major climate impacts beyond air temperatures.

interstitial

  • Young ice
  • Posts: 2867
    • View Profile
  • Liked: 567
  • Likes Given: 96
Re: Ocean temperatures
« Reply #82 on: October 10, 2022, 02:26:42 AM »
All they are saying is when the difference between atmospheric and ocean temperatures are greater the energy moves from the atmosphere to the ocean faster.  Best not to think of it as a delay but as an acceleration of dumping heat into the ocean because the air is getting hotter.

The Walrus

  • Young ice
  • Posts: 2827
    • View Profile
  • Liked: 149
  • Likes Given: 484
Re: Ocean temperatures
« Reply #83 on: October 10, 2022, 04:08:53 AM »
The peak intensities of storms over the ocean are increasing. The strongest hurricanes are getting stronger and rapid intensification of cyclones is increasing the danger.

All evidence to the contrary.

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #84 on: October 10, 2022, 02:52:42 PM »
You did forget to add it though.
Any discussions of this can go into the storms thread.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #85 on: October 10, 2022, 03:18:26 PM »
Winds Of Change Drive “Alarming” Rate Of Ocean Warming

Researchers from UNSW Sydney say changes to strong, large-scale wind patterns are causing western boundary currents in the Southern Hemisphere to rapidly warm — transforming weather and habitats across the world.

The western boundary currents of the ocean — which includes the East Australian Current — transport large amounts of heat towards Earth’s poles. These currents are crucial in moderating global coastal climates. In the past few decades, their poleward extension regions have warmed two to three times hotter than the global average, creating ocean “hotspots” — but no one knew why these regions were warming so fast.

In a study published in Nature Climate Change this past week, UNSW Sydney researchers from the School of Biological, Earth and Environmental Sciences uncover the mystery behind the warming.

“We discovered the rapid warming is driven by climate change causing the easterly winds at mid-latitudes to shift south,” said lead author Dr Junde Li.

Dr Li said this was causing an increase in the number of eddies in the western boundary current poleward extensions — large whirlpools in the ocean that retain and transport warm ocean waters.

https://cleantechnica.com/2022/10/07/winds-of-change-drive-alarming-rate-of-ocean-warming/
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

FishOutofWater

  • Nilas ice
  • Posts: 1088
    • View Profile
  • Liked: 696
  • Likes Given: 332
Re: Ocean temperatures
« Reply #86 on: October 10, 2022, 11:05:56 PM »
The interactions between the ocean and atmosphere are very complicated as CO2 levels rise. Ninety percent plus of the energy imbalance caused by increasing ghg levels goes into heating the oceans. That said, the changes in the radiation patterns are complex and couple with the uptake of ocean heat and changes in atmospheric dynamics. Here's a link to a recent paper that agrees with the conclusions above about the warming of the southern ocean.

https://www.nature.com/articles/s41612-022-00287-x

In particular, the amplification is much more pronounced for the southern compared to the northern HC in response to MLAT forcing (Fig. 4e). This hemispheric asymmetry arises because a larger increase in ocean heat uptake takes place in the southern compared to the northern extratropics (Fig. 5e), potentially due to a greater ocean fraction and continental geometry, so that the HC strengthening from ocean heat uptake is 4.8 times larger for the southern than the northern cell (Fig. 4e).


P-maker

  • Frazil ice
  • Posts: 389
    • View Profile
  • Liked: 72
  • Likes Given: 0
Re: Ocean temperatures
« Reply #87 on: October 28, 2022, 12:03:26 AM »
Howcome, none of you clever guys ever came across this new research article?

https://www.google.dk/search?q=gambio+arctic+seaice+elnino&ie=UTF-8&oe=UTF-8&hl=da-dk&client=safari or here: https://phys.org/news/2022-09-arctic-sea-ice-loss-frequent.html or here: https://news.mongabay.com/2022/10/arctic-sea-ice-loss-to-increase-strong-el-nino-events-linked-to-extreme-weather-study/

It shows a terrifying connection between the loss of Arctic sea ice and more extreme El Nino events.
« Last Edit: October 28, 2022, 12:12:58 AM by P-maker »

vox_mundi

  • Multi-year ice
  • Posts: 10153
    • View Profile
  • Liked: 3510
  • Likes Given: 745
Re: Ocean temperatures
« Reply #88 on: October 28, 2022, 12:36:58 AM »
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

P-maker

  • Frazil ice
  • Posts: 389
    • View Profile
  • Liked: 72
  • Likes Given: 0
Re: Ocean temperatures
« Reply #89 on: October 28, 2022, 07:52:51 AM »
Vox_mundi, my bad.

Sorry to have missed your post. It must have slipped under my radar in the middle of the night. I somehow knew that I could count on you.

Cheers P

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #90 on: October 28, 2022, 04:58:08 PM »
Quote
Before running the simulations, they directly fixed Arctic sea ice cover during three time periods—1980–99, 2020–2039 and 2080–99. The simulations were generated using the National Center for Atmospheric Research's Community Climate System Model, a global climate model that provides state-of-the-art computer simulations of the Earth's past, present and future climate states.

...

By comparing the simulations, the researchers found no significant change in the occurrence of strong El Niño events in response to moderate Arctic sea-ice loss, which is consistent with satellite observations to date. However, as the ice loss continues and the Arctic becomes seasonally ice-free, the frequency of strong El Niño events increases by more than one-third.

and from the abstract:

Quote
In the tropical Pacific, the response to the moderate reduction in Arctic sea ice of ICEp1 shows a very weak basin-wide SST warming and minimal changes in zonal winds (Supplementary Fig. 2a) and the thermocline across the equatorial Pacific. In contrast, the seasonally ice-free Arctic of ICEp2 induces pronounced changes in the mean state of the tropical Pacific that are reminiscent of El Niño. A greatly enhanced warming is observed in the equatorial Pacific with much larger anomalies of 0.8–1 °C in the east, which are associated with pronounced westerly wind anomalies in the central and eastern equatorial Pacific (Supplementary Fig. 2b). The weakened trade winds reduce the zonal tilt of the equatorial thermocline23 and weaken the meridional ocean circulation (the so-called tropical cell), particularly on the south side of the equator (Supplementary Fig. 3). Both changes contribute to the intensified eastern warming in the upper ocean.

Two short preview bits. It does not directly mention ocean temperatures and the rise is for modelling late century conditions. It is also in the ENSO thread albeit a few days later then the WNITA version.

Bottom line: asking did you miss this or did i miss it is slightly safer.  ;)
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

gerontocrat

  • Multi-year ice
  • Posts: 20370
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Ocean temperatures
« Reply #91 on: June 02, 2023, 11:16:33 PM »
Climate reanalyzer produces graphs of daily World and North Atlantic SSTS. But it is hard to extract trens from a forest of lines on the graph.

But they also allow download of the data. Here is my 2nd attempt. The first two graphs show the decadal trends (only 9 years for the 1980s) and recent years, which showed me that the years 2020 to date are all very high.

So the next two graphs show the variation from the +2SD variation from the 1982-2011 mean.

The World Graph shows that daily SSTs for the years 2020 to 2022 are mostly between 0.1 and 0.2 degrees celsius above the +2SD level, while 2023 is already at more than +0.3.

The North Atlantic daily SSTs show a similar pattern, with SSTs for the years 2020 to 2022 are mostly between 0.0 and 0.2 degrees celsius above the +2SD level, but with one major difference.
In June and July there is a big dip in SSTS relative to +2SD, in early Julu as much as 0.3 degrees below the +2SD value.

Will 2023 SSTs, currently at 0.3 degrees above the +2SD value, also show a similar dip?

click images to enlarge
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

  • Multi-year ice
  • Posts: 20370
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: Ocean temperatures
« Reply #92 on: June 09, 2023, 10:34:00 PM »
https://climatereanalyzer.org/clim/sst_daily/

Graphs to June 8 - the only way is up.....
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

kiwichick16

  • Grease ice
  • Posts: 906
    • View Profile
  • Liked: 87
  • Likes Given: 35
Re: Ocean temperatures
« Reply #93 on: June 10, 2023, 10:32:03 AM »
with apologies to Peter Benchley..... you are going to need a bigger graph

Freegrass

  • Young ice
  • Posts: 3825
  • Autodidacticism is a complicated word...
    • View Profile
  • Liked: 951
  • Likes Given: 1251
Re: Ocean temperatures
« Reply #94 on: June 10, 2023, 11:43:42 AM »
Can this ocean temp thread - that's out of place in science - be closed or merged? Like Gero said, it's confusing...
90% of the world is religious, but somehow "love thy neighbour" became "fuck thy neighbours", if they don't agree with your point of view.

WTF happened?

kassy

  • Moderator
  • First-year ice
  • Posts: 8234
    • View Profile
  • Liked: 2041
  • Likes Given: 1986
Re: Ocean temperatures
« Reply #95 on: June 10, 2023, 02:44:17 PM »
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.