Claim: World’s Ocean Is Losing Its Memory Under Global Warming


Peer-Reviewed Publication

UNIVERSITY OF HAWAII AT MANOA

Global map of declining ocean memory
IMAGE: DECLINING OCEAN MEMORY BETWEEN THE PRESENT AND THE END OF THE 21ST CENTURY–BLUE INDICATES DECLINE, RED INDICATES INCREASE IN MEMORY. view more  CREDIT: SHI, ET AL. (2022)

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. 

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.

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.

The research is a collaboration among scientists at:
●    Farallon Institute 
●    University of Hawaii at Manoa
●    University of Washington 
●    NOAA Southwest Fisheries Science Center
●    NOAA Physical Sciences Laboratory 
●    University of Arizona 
●    NOAA Pacific Islands Fisheries Science Center


JOURNAL

Science Advances

DOI

10.1126/sciadv.abm3468 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Global decline in ocean memory over the 21st century

ARTICLE PUBLICATION DATE

6-May-2022

COI STATEMENT

The authors declare that they have no competing interests

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May 8, 2022 1:04 pm

Someone watched Moana too many times. The ocean has memory…

Richard Page
Reply to  stinkerp
May 8, 2022 3:03 pm

That’s what happens when morons use critical race theory instead of science.

Bruce Cobb
May 8, 2022 1:20 pm

The oceans are pretty old so some memory loss is to be expected.

Marcus
May 8, 2022 1:34 pm

“Using future projections from the latest generation of Earth System Models”

Models that have the brain power of Brandon !

May 8, 2022 1:58 pm

” World’s Ocean Is Losing Its Memory Under Global Warming ”
Phosphorus is essential for not losing memory.

May 8, 2022 2:15 pm

That’s better than “climate scientists” losing their minds over ~1°C warming.

Old Cocky
May 8, 2022 2:19 pm

The full paper must have been too long, so it’s been split into parts. They publish the models first, to be followed by the observations and comparison.

dmacleo
May 8, 2022 2:55 pm

‘member when the oceans did this?

Pepperidge Farm remembers.

May 8, 2022 3:14 pm

Male bovine excrement, by the ton.

Doug
May 8, 2022 7:39 pm

How absolutely stupid can a person be …a non sentient entity has no memory to lose or use . Anthropology run amuck.
No wonder only the terminal ignorant fall for this crap.

Clyde Spencer
May 8, 2022 8:58 pm

It strikes me that alarmists must have brain storming events to see if they can invent any more possible negative effects by humans on Earth. As the more obvious ones are trotted out the remaining ones become even more of a stretch. Referring to auto-correlation as “memory” would seem to be an attempt to appeal to empathy by anthropomorphizing the oceans. Are they getting desperate?

MarkMcD
May 8, 2022 9:38 pm

Using future projections from the latest generation of Earth System Models

Translation: Using prophecy from the latest made-up GIGO junk…

Alt translation: Ze misty, crystal ball iz clearing unt zose who haf passed wish to speak wit you.

Mr David Guy-Johnson
May 8, 2022 10:20 pm

Rarely have I read such a load of rubbish

jono1066
May 9, 2022 4:42 am

while talking about the uppermost layer of the ocean, they state “Deeper mixed layers have greater heat content”
I need to learn something here as I thought it got colder (less heat content) lower down
?

Old Cocky
Reply to  jono1066
May 9, 2022 2:04 pm

Lower temperatures, but greater volume.

kwinterkorn
May 9, 2022 6:42 am

Once again, “scientists” who wrote this article confuse the output of theoretical climate with physical evidence. They write as if they had discovered some facts about the real world.

Instead, they have only added to quantification of their theories. Only real world measurements can confirm or deny theory or projections of theory. Scientists used to understand this.

The language in the article should be only in the “if….,then….” mode, not the “We find…” mode.

This article is not science.

Duane
May 9, 2022 7:54 am

My gawd, this sounds exactly like something a so-called “scientist” from a non-science background would say, turning the oceans into mental patients who are suffering alzheimers.

A real scientist would never resort to using such goggledygook bullshit terms.

The real scientific terms include concepts like the specific heat capacity of liquid water, and the comparative mass of the oceans to the mass of the atmosphere. And the various laws of thermodynamics.

Reply to  Duane
May 9, 2022 8:41 am

….that’s all too difficult. It involves math.

May 9, 2022 9:02 am

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.

Sounds like an issue with the models; I don’t see anywhere claiming this behavior occurs in the real oceans. We’ve had 3,000 operational ARGO buoys since late 2007. You’d think if there was a trend in year-to-year temperature you could find it in almost 15 years of reasonably comprehensive data. Instead, they examine model outputs.

If models are all you have then we can discuss what they purport to show. But if you ignore real data to consider only models, you might as well be reading Tarot cards.

May 9, 2022 9:40 am

Title of above article:

“Claim: World’s Ocean Is Losing Its Memory Under Global Warming”

Heck, that’s nothing . . . most of industrialized Western nations, the IPCC, the Biden administration, and the MSM have lost their collective minds over Global Warming.

May 9, 2022 10:20 am

they made a big mistake! They used nice cool blue on there graphic, it doesnt look menacing like a nice dark red does.

Robert of Ottawa
May 9, 2022 3:59 pm

Ocean losing its memory? Research grant seekers losing their minds.