Hokkaido University
Even though the deeper layers of the ocean are warming at a slower pace than the surface, animals living in the deep ocean are more exposed to climate warming and will face increasing challenges to maintain their preferred thermal habitats in the future.
Reporting in the journal Nature Climate Change, an international team of scientists, led by the University of Queensland in Australia and involving Hokkaido University, analyzed contemporary and future global patterns of the velocity of climate change across the depths of the ocean. Their metric describes the temporal rate and direction of temperature changes, as a proxy for potential shifts of marine biota in response to climate warming.
Despite rapid surface warming, the team found that global mean climate velocities in the deepest layers of the ocean (>1,000 m) have been 2 to nearly 4-fold faster than at surface over the second half of the 20th century. The authors point to the greater thermal homogeneity of the deep ocean environment as responsible for these larger velocities. Moreover, while climate velocities are projected to slow down under scenarios contemplating strong mitigation of greenhouse gas emissions (RCP2.6), they will continue to accelerate in the deep ocean.
“Our results suggest that deep sea biodiversity is likely to be at greater risk because they are adapted to much more stable thermal environments,” says Jorge Garci?a Molinos, a climate ecologist at Hokkaido University’s Arctic Research Center, who contributed to the study. “The acceleration of climate velocity for the deep ocean is consistent through all tested greenhouse gas concentration scenarios. This provides strong motivation to consider the future impacts of ocean warming to deep ocean biodiversity, which remains worryingly understudied.”
Climate velocities in the mesopelagic layer of the ocean (200-1000 m) are projected to be between 4 to 11 times higher than current velocities at the surface by the end of this century. Marine life in the mesopelagic layer includes great abundance of small fish that are food for larger animals, including tuna and squid. This could present additional challenges for commercial fisheries if predators and their prey further down the water column do not follow similar range shifts.
The authors also compared resulting spatial patterns of contemporary climate velocity with those of marine biodiversity for over 20,000 marine species to show potential areas of risk, where high biodiversity and velocity overlap. They found that, while risk areas for surface and intermediate layers dominate in tropical and subtropical latitudes, those of the deepest layers are widespread across all latitudes except for polar regions.
The scientists caution that while uncertainty of the results increases with depth, life in the deep ocean is also limited by many factors other than temperature, such as pressure, light or oxygen concentrations. “Without knowing if and how well deep ocean species can adapt to these changes, we recommend to follow a precautionary approach that limits the negative effects from other human activities such as deep-sea mining and fishing, as well as planning for climate-smart networks of large Marine Protected Areas for the deeper ocean,” says Garci?a Molinos.
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So they have to adjust the distance to keep from the black smokers?
This crap is also being pushed by the intellectually challenged Graham Readfearn at the Guardian.
“Climate change in deep oceans could be seven times faster by middle of century, report says
Uneven heating could have major impact on marine wildlife, as species that rely on each other for survival are forced to move”
https://www.theguardian.com/environment/2020/may/26/climate-change-in-deep-oceans-could-be-seven-times-faster-by-middle-of-century-report-says
Another climate change activist with a media keyboard.
“Our results suggest that deep sea biodiversity is likely to be at greater risk because they are adapted to much more stable thermal environments,”
I have not read the study but I expect this conclusion has little scientific support, i.e., it just sounds good. Do they have references where unstable thermal environments have been studied and bad outcomes documented? My guess is that this is considered consensus opinion rather than documented science.
But it contains lots of deep red Danger! graphics.
The study is paywalled, but nothing in the figures appears to be quantifying the biological impact if the marine wildlife just doesn’t move. A number of the references appear to be actual impact studies from their titles; but given the tiny amount of warming experienced, the error in measuring actual local temperature, and the difficulty of studying marine life in fraction-of-degree differentials inside the ocean, I’d be flabbergasted if there were any impact studies in existence that are both solid science and show significant effects. Please correct me if there’s any such non-paywalled study to examine.
Still, judging from the abstract *this* paper is about the *relative* speeds of climate velocity between layers of the ocean (current and projected future), which has nothing at all to do with whether the observed/predicted climate velocity actually matters biologically at all. It would be appropriate for them to see how well the models used to project the future did at projecting the past, but I see no hint of that in the figures either.
The good news is that it’s too late to do anything about “climate velocity”, even under RCP 2.6, so the abstract is calling for different policies instead of aggressive mitigation: “To optimize opportunities for climate adaptation among deep-ocean communities, future open-ocean protected areas must be designed to retain species moving at different speeds at different depths under climate change while managing non-climate threats, such as fishing and mining.” (Of course, I’m sure the authors are all in favor of aggressive mitigation as well….)
The idea that marine biology is incapable of adapting to temperature increases that are both very very tiny and very very slow goes against everything I’ve ever heard or read about natural selection. Advocating specific policy proposals, as the abstract does, isn’t science at all.
Jim
Ocean temperature at all depths is changing all the time, and life changes with it.
For instance 2.6 million years ago the Pleistocene began with the connection of North and South Americas. A major oceanic rearrangement and cooling followed. Up to 40% of whale species went extinct as did the Megalodon shark which predated on whales. However whales then got much larger as the polar seas became extremely productive of plankton due to the strong vertical mixing and nutrient upwelling caused by the cold temperatures.
https://youtu.be/BTPcq2HczVY
“Uneven heating could have major impact on marine wildlife, as species that rely on each other for survival are forced to move”
Follow the food!
Every freshman oceanographer knows that vast populations of aquatic organisms move toward better conditions all the time (daily is common). The “vastness” of their numbers tells us that not all make it to the better conditions…but because of the big numbers…enough do remain in existence. That is the way this world works. If a species doesn’t do things to survive variations in conditions that happen with regularity on this planet, that species ceases to exist.
Every species in existence today has passed the test of surviving temperature variations an order of magnitude greater than is possible (from CO2 effects) in the next several centuries.
If climate change is not halted soon, sin waves will turn into sawtooth waves.
toorightmate
No, sin has always been with us, and probably always will be.
Clyde this person is truly ambitious, they want to stop climate change and sin too? Good luck with that, though they could appease somewhat by scrapping the sin that is renewables. Conflict of interests?
While the “uncertainty of the results increases with depth“ the certainty that we are all gonna fry and destroy the biosphere increases the more superficial the analysis. According to the type of logic supporting this and other similar papers there should be no life on Earth having been wiped out long ago by much more substantial and natural changes in climate. What gives?
That was natural change over millennia. Now it is due to humans all at once.
Sarc off. And yes, I have heard this excuse.
“… the team found that global mean climate velocities in the deepest layers of the ocean (>1,000 m) have been 2 to nearly 4-fold faster than at surface over the second half of the 20th century.”
The above statement appears to be in opposition to previous studies:
“Scientists at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, analyzed satellite and direct ocean temperature data from 2005 to 2013 and found the ocean abyss below 1.24 miles (1,995 meters) has not warmed measurably.”
https://scitechdaily.com/nasa-data-show-earths-deep-ocean-warmed/
Another news article has the lead author stating, ““We calculated the climate velocity throughout the ocean for the past 50 years and then for the rest of this century using data from 11 climate models.” It doesn’t mention which models were chosen. More importantly, it doesn’t mention if the Russian model was one of the eleven.
Good lord, not only the future but also the past is purely modelled?
The scariest, most evil and dangerous heat of all though, is the “hidden heat”. See, it’s the heat you can’t see that gets you. At least one gazillion hiroshimas worth of heat has gone AWOL, into the oceans without so much as a by-your-leave. We know this because of highly accurate models known as GCMs. These have been developed and fine-tuned over the years by thousands of scientists using state-of-the-art technology processing literally trillions of data points, so we know they can’t be wrong.
/sarcnado
B.S.
100% of the Deep sea species were around during the last several (if not all of) glaciations. During that span of time, the oceans have been a lot warmer (sea level 100 m higher) and a lot colder (sea levels 100’s of m lower).
What scientist would assume that these creaturs would not adapt to a quarter of a degree temperature variance? And it is not likely that the Deep oceans will ever see 1/4 degree change in the next 4 centuries.
“Despite rapid surface warming, the team found that global mean climate velocities in the deepest layers of the ocean (>1,000 m) have been 2 to nearly 4-fold faster than at surface over the second half of the 20th century. The authors point to the greater thermal homogeneity of the deep ocean environment as responsible for these larger velocities.”
Huh? Heat transport in an homogeneous media like the ocean is almost all conduction, especially at depth. Have none of the AGW alarmists ever heard of the Law of Conduction?
if u = u(x, y, z, t) then the partial of u with respect to the partial of t (i.e. the rate of change of temperature) gives the velocity of change of u at any point.
If you make the following assumptions:
1. the ocean is an infinite plane of infinite depth
2. the ocean surface is a constant temperature in x and y.
3. the ocean is a homogeneous medium
Then the partial of u with respect to the partial of t is:
A(the second partial derivative of u with respect to the second partial derivative of z. )
where A is the thermal conductivity of the medium.
I know this is simplistic but I can’t find my thermodynamic textbook from 50 years ago right now. Simplistically, however, this basically says a point x below the surface of the ocean changes in a direct relationship to the surface of the ocean.
(please – I understand that there are lots of other factors such as colder, denser water sinks. It’s why I made the simplifying assumptions. But it is still a fact that the deep water cannot just change its temperature on its own, it has to be driven by heat being transported from the surface according to the conduction equation. There is no Star Trek transporter somewhere out in space.)
Tim
My suspicion is that your remarks will go right over the heads of most of those (Nick Stokes excepted, he has other issues.) who are acolytes of the religion of Gaia. As an example, where is Loydo? Is he/she criticizing your statement? Crickets!
So what???????????????????????????????????????