Botanist claims to overturn established ocean phytoplankton theory – cites global warming as a concern for new theory

Via Eurekalert: “A new study concludes that an old, fundamental and widely accepted theory of how and why phytoplankton bloom in the oceans is incorrect. The findings challenge more than 50 years of conventional wisdom about the growth of phytoplankton, which are the ultimate basis for almost all ocean life and major fisheries. And they also raise concerns that global warming, rather than stimulating ocean productivity, may actually curtail it in some places.”

I’m skeptical of the claim made about GW “stratifying the oceans, resulting in less mixing” because as we’ve been told many times, A Warming World Means More Destructive Storms.

So, which is it? AGW means more storms? Less storms? A storm free Arctic?

On the plus side, they included the actual paper with the press release at OSU, unlike many universities that hide it behind a paywall from the public, making them pay for taxpayer funded research twice. Kudos to OSU. – Anthony

Phytoplankton by Oregon State University.

A north Atlantic Ocean view of the spring phytoplankton bloom, as seen from a satellite image. (Image courtesy of Oregon State University)

Media Release

Findings overturn old theory of phytoplankton growth, raise concerns for ocean productivity

The journal publication the story is based on is available online: http://bit.ly/aTUM3V

CORVALLIS, Ore. – A new study concludes that an old, fundamental and widely accepted theory of how and why phytoplankton bloom in the oceans is incorrect.

The findings challenge more than 50 years of conventional wisdom about the growth of phytoplankton, which are the ultimate basis for almost all ocean life and major fisheries. And they also raise concerns that global warming, rather than stimulating ocean productivity, may actually curtail it in some places.

This analysis was published in the journal Ecology by Michael Behrenfeld, a professor of botany at Oregon State University, and one of the world’s leading experts in the use of remote sensing technology to examine ocean productivity. The study was supported by NASA.

The new research concludes that a theory first developed in 1953 called the “critical depth hypothesis” offers an incomplete and inaccurate explanation for summer phytoplankton blooms that have been observed since the 1800s in the North Atlantic Ocean. These blooms provide the basis for one of the world’s most productive fisheries.

“The old theory made common sense and seemed to explain what people were seeing,” Behrenfeld said.

“It was based on the best science and data that were available at the time, most of which was obtained during the calmer seasons of late spring and early summer,” he said. “But now we have satellite remote sensing technology that provides us with a much more comprehensive view of the oceans on literally a daily basis. And those data strongly contradict the critical depth hypothesis.”

That hypothesis, commonly found in oceanographic textbooks, stated that phytoplankton bloom in temperate oceans in the spring because of improving light conditions – longer and brighter days – and warming of the surface layer.  Warm water is less dense than cold water, so springtime warming creates a surface layer that essentially “floats” on top of the cold water below, slows wind-driven mixing and holds the phytoplankton in the sunlit upper layer more of the time, letting them grow faster.

There’s a problem: a nine-year analysis of satellite records of chlorophyll and carbon data indicate that this long-held hypothesis is not true. The rate of phytoplankton accumulation actually begins to surge during the middle of winter, the coldest, darkest time of year.

The fundamental flaw of the previous theory, Behrenfeld said, is that it didn’t adequately account for seasonal changes in the activity of the zooplankton – very tiny marine animals – in particular their feeding rate on the phytoplankton.

“To understand phytoplankton abundance, we’ve been paying way too much attention to phytoplankton growth and way too little attention to loss rates, particularly consumption by zooplankton,” Behrenfeld said. “When zooplankton are abundant and can find food, they eat phytoplankton almost as fast as it grows.”

The new theory that Behrenfeld has developed, called the “dilution-recoupling hypothesis,” suggests that the spring bloom depends on processes occurring earlier in the fall and winter. As winter storms become more frequent and intense, the biologically-rich surface layer mixes with cold, almost clear and lifeless water from deeper levels. This dilutes the concentration of phytoplankton and zooplankton, making it more difficult for the zooplankton to find the phytoplankton and eat them – so more phytoplankton survive and populations begin to increase during the dark, cold days of winter.

In the spring, storms subside and the phytoplankton and zooplankton are no longer regularly diluted.  Zooplankton find their prey more easily as the concentration of phytoplankton rises. So even though the phytoplankton get more light and their growth rate increases, the voracious feeding of the zooplankton keeps them largely in-check, and the overall rise in phytoplankton occurs at roughly the same rate from winter to late spring. Eventually in mid-summer, the phytoplankton run out of nutrients and the now abundant zooplankton easily overtake them, and the bloom ends with a rapid crash.

“What the satellite data appear to be telling us is that the physical mixing of water has as much or more to do with the success of the bloom as does the rate of phytoplankton photosynthesis,” Behrenfeld said. “Big blooms appear to require deeper wintertime mixing.”

That’s a concern, he said, because with further global warming, many ocean regions are expected to become warmer and more stratified. In places where this process is operating – which includes the North Atlantic, western North Pacific, and Southern Ocean around Antarctica – that could lead to lower phytoplankton growth and less overall ocean productivity, less life in the oceans. These forces also affect carbon balances in the oceans, and an accurate understanding of them is needed for use in global climate models.

Worth noting, Behrenfeld said, is that some of these regions with large seasonal phytoplankton blooms are among the world’s most dynamic fisheries.

The critical depth hypothesis would suggest that a warmer climate would increase ocean productivity. Behrenfeld’s new hypothesis suggests the opposite.

Behrenfeld said that oceans are very complex, water mixing and currents can be affected by various forces, and more research and observation will be needed to fully understand potential future impacts. However, some oceanographers will need to go back to the drawing board.

“With the satellite record of net population growth rates in the North Atlantic, we can now dismiss the critical depth hypothesis as a valid explanation for bloom initiation,” he wrote in the report.

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71 thoughts on “Botanist claims to overturn established ocean phytoplankton theory – cites global warming as a concern for new theory

  1. Warming means more storms which means more nutrients and more mixing, so theory FAIL.
    NEXT!!!

  2. Depending on which measurement you use, ocean temperatures are cooling, flat, or warming. No clear trend yet. (Right?)

  3. ‘That’s a concern, he said, because with further global warming, many ocean regions are expected to become warmer and more stratified.’
    Is this actually happening? Or is it just the hook for more grant money?

  4. Not having a PhD in anything I am probably not the right person to interpret this research. I find the Professor’s reasoning difficult to follow:
    1.) ‘As winter storms become more frequent and intense, the biologically-rich surface layer mixes with cold, almost clear and lifeless water from deeper levels. This dilutes the concentration of phytoplankton and zooplankton, making it more difficult for the zooplankton to find the phytoplankton and eat them – so more phytoplankton survive and populations begin to increase during the dark, cold days of winter.’
    a. The first sentence is quite clear; the second sentence seems to be contradicting itself, if there’s less, the more it grows.
    b. I have always been led to understand that Phytoplankton is so named because it needs light to live and multiply. What mechanism does the Professor propose the light dependant plankton use to live and multiply in the dark and cold?
    2.) ‘Zooplankton find their prey more easily as the concentration of phytoplankton rises.’
    a.) Yet again I cannot follow his logic: if the zooplankton find the phytoplankton more easily and devour them with speed, how come the phytoplankton increase so fast?

  5. ““The old theory made common sense and seemed to explain what people were seeing,” Behrenfeld said……..There’s a problem: a nine-year analysis of satellite records of chlorophyll and carbon data indicate that this long-held hypothesis is not true. The rate of phytoplankton accumulation actually begins to surge during the middle of winter, the coldest, darkest time of year.”

    But there was a consensus. The consensus is correct surely!!!

  6. So if phytoplankton are the base of the oceanic food chain and they don’t do well in warm water then how does the good professor explain how the Gulf of Mexico is one of most productive fisheries in the world? Non sequitur.

  7. I am embarrassed to say it but this is my field.
    Whens zoos are abundant, it’s because their food is abundant, not the other way around.
    They obviously need to get new books, they are reading Chemical Oceanography by Frank Millero. That book is an embarrassment to everyone in this field and people that do not know any better claim it’s the bible.
    This is just another re-hash of the same old ‘currents are going to stop’ BS. One week global warming makes more storms, and the next week global warming makes less storms.
    No wonder people are getting sick and tired of this.

  8. “….with further global warming, many ocean regions are expected to become warmer and more stratified.”
    “Behrenfeld said that oceans are very complex, water mixing and currents can be affected by various forces, and more research and observation will be needed to fully understand potential future impacts.”

    According to the IPCC

    “Nonetheless, clear evidence exists for increases in category 4 and 5 storms globally since 1970 along with increases in the PDI due to increases in intensity and duration of storms. The 2005 season in the North Atlantic broke many records.” Source IPCC Summary

    What a croc!!!

  9. “I’m skeptical of the claim made about GW “stratifying the oceans, resulting in less mixing” because as we’ve been told many times, A Warming World Means More Destructive Storms. ”
    I don’t know much about how TCs start up. But I don’t immediately see why a more stratified ocean means less destructive storms, as Watts seems to be implying here. Spell it out a bit?
    REPLY: I recalled this story for example: http://www.nasa.gov/vision/earth/lookingatearth/giovanni.html
    “Strong cyclonic surface winds of hurricanes are known to mix ocean surface waters, a process which brings nutrients and dissolved organic matter (carbon-based material created by biological activity in the oceans) to the sea surface from the lower depths of the ocean. With enough sunlight and the right temperatures and nutrients, phytoplankton, or free-floating unicellular aquatic algae, can grow quickly after a hurricane passes.”
    Not just there. subtropical cyclone tracks often end up at higher latitudes where they dissipate. So they stir water over a long track, and currents further disperse. – Anthony

  10. I start to feel like a boxer slugged groggy with misinformation, halftruths, assumptions, selfcontradictory theories, proof that proves proof isn’t proof.
    All what is clear: No prediction made about AGW has come to fruition. We are now in the ‘wait for it’ holding pattern. It doesn’t happen now, but oh boy it will and when it does…..
    I guess i’ll live out my remaining years in about the same climate i’ve been living in since birth. And then, apres moi la deluge.

  11. Even assuming that the “CO2 with water vapor feedback” global warming is taking place in the atmosphere, i doubt that this will have much effect on ocean temperatures. LWIR doesn’t penetrate water; we don’t use hairdryers to cook water and we don’t use fans to cool water. The density of air is too low to warm or cool big amounts of water. The oceans can only get their heat from visible sunlight. So why should a GHG effect have any measurable effect on the oceans? Is there any paper trail by the AGW scientists that shows a link? Do they automatically assume that slightly higher global atmospheric temperature averages have any impact on oceanic temperatures or is that a consequence of GCM’s ? And even if the oceans were getting warmer, does this automatically lead to more “stratification”? Can that be observed in warmer parts of the oceans?

  12. “Behrenfeld said that oceans are very complex, water mixing and currents can be affected by various forces, and more research and observation will be needed to fully understand potential future impacts.”
    Yes, of course. More funding is needed. Why didn’t they say so in the first place, and skip all that other nonsense?

  13. carrot eater:

    I don’t know much about how TCs start up. But I don’t immediately see why a more stratified ocean means less destructive storms, as Watts seems to be implying here. Spell it out a bit?

    No, you’re inferring that. What is implied is that this “stratification” of the ocean can’t take place if there are more intense storms. More storms means more mixing, not less. If warming causes more storms then it cannot also cause more stratification.

  14. I am amazed at th authors not seeing the lack of logic in two statements, the first of which is:
    “As winter storms become more frequent and intense, the biologically-rich surface layer mixes with cold, almost clear and lifeless water from deeper levels.”
    Then a bit later, is this:
    ” . . because with further global warming, many ocean regions are expected to become warmer and more stratified.”
    OK, if winter storms are to become more frequent and intense, resulting in deeper mixing, then how is the ocean to become more stratified, assuming both are from global warming? Ya can’t have it both ways . . .

  15. “So, which is it? AGW means more storms? Less storms? A storm free Arctic?”
    Probably whichever validates their meme this week.
    I found this article to be very interesting.

    New findings have revealed that massive amounts of carbon are converted into “inedible” forms of organic carbon that remain out of circulation for thousands of years, effectively sequestering the carbon by removing it from the ocean food chain. According to Jiao Nianzhi, a microbial ecologist here at Xiamen University, the amount stored is tremendous: “It’s really huge. It’s comparable to all the carbon dioxide in the air.”

  16. Oh dear, a theory that was accepted by 100% of the discipline for over 50 years has turned out to be wrong. There must have been at least one blacklisted oceanographer in the 1950s who disagreed with the consensus – Hey you oceanographers must know who he/she was – make a good post.
    Re the progression of global warming, check out DMI -temps above 80 degrees N appear to be plunging a month and a half early – its going to be a cold winter (Steve G take note):
    http://ocean.dmi.dk/arctic/meant80n.uk.php
    Oh and annoyingly, the color-coded temp map of intelliweather is miscolored again. It shows Toronto cool at 86F and Atlanta hot at 84F:
    http://www.intelliweather.net/imagery/intelliweather/tempcity_nat_640x480.jpg

  17. Nick Luke, I too am not a PhD, but I think I can explain what was said:
    1. The winter storms mix “lifeless” cold water from below to the top.
    2. The top water now is relatively spread out with regard to zoo and phyto plankton.
    3. Spread out, the zoo can’t find the phyto as easily, so the phyto can grow while being eaten more slowly, and there’s a bloom.
    4. The bloom makes it easier for the zoo to locate phyto, and they do, crashing the bloom.

  18. OK, I’m only an Engineer.
    But wouldn’t the good professor have made his thesis a little clearer if his nice North Atlantic ocean view used the cool colours for more phytoplankton and the warm colours for less phytoplankton?
    But perhaps he swiped the illustration from a paper showing the previous hypothesis?
    Worse than we thought! (academia).

  19. I’m not expert on this subject, far from it.
    It does make sense to me that phytoplankon can bloom in February and March — sure, it’s darker, but there’s still considerable available light, and the proof seems to be that the phytoplankton actually do grow at that time.
    But it doesn’t make intuitive sense to me that increased mixing means that zooplankton can’t find their prey. Plankton can travel considerable distances. In parts of the Pacific, I’ve read, plankton come near the surface by day and sink several hundred feet at night, on a diurnal basis. But perhaps zooplankton aren’t as active in the coldest weather. Many plants and animals as a survival strategy breed or emerge when predators aren’t yet abundant, so that could be happening.
    Why do the blooms fade out? Nutrient depletion seems to be key, because the phytoplanton keep on blooming in the spring, when the zooplankton graze on them. And the lack of vertical mixing may be key to the fading of the blooms.
    The North Atlantic is quite different from the Southern Ocean. Down there, you NEED mixing to bring iron up to the surface, to create a plankton bloom, because iron is the limiting nutrient. But it appears from this Science Daily article that perhaps nutrient limitation due to lack of mixing occurs in the North Atlantic as well:
    http://www.sciencedaily.com/releases/2009/07/090707111711.htm
    So will we see less vertical mixing in the future, in a slightly to somewhat warmer world?
    There are a couple of parts to this argument (at least).
    One is that the North Atlantic will become less stormy. Tropical storminess and storminess in the North Atlantic have different origins, I would think, so it wouldn’t make sense to make a parallel with tropical cyclones in a warmer world. If the world is 1 to 2 degrees warmer, F, on average, will the North Atlantic be less stormy? I don’t know the reasoning for why it would be, I’m just unknowledgeable, other than to say that it doesn’t have much to do with hurricane formation and intensity.
    Another part is to ask whether there was both increased stratification AND less nutrient availability when the earth was much warmer. The Eocene, when crocodiles and were near the north pole, would be a good test case.
    Latitude, can you tell us anything about stratification and nutrient availability in the Eocene? Anyone else?

  20. Archonix,
    Thank you. I suppose I took the cause-and-effect intended in Anthony’s statement exactly backwards, and thus I was confused.
    Though I don’t think there’s an inconsistency there. Climate change can bring about changes in the thermocline, even if individual storms brings some mixing between surface and the deeper waters. How long do you expect such effects from a single storm to last, after all?

  21. It’s plausible to think that preditor and prey abundances as well as limiting physical factors (light and nutrients) are important regulating factors of plankton blooms. In fact, it’s not a very new idea at all. But when the global warming *IF* gets tacked on, ecological science drifts off into the realm of psychic speculation.

  22. So sad; once again good science polluted with a forced AGW tie-in. The paper was really good until the end. The nice thing about this theory, is that it is testable.

  23. DR, if nothing else this is perfect example of why the entire peer review process is a total crock……
    “This dilutes the concentration of phytoplankton and zooplankton, making it more difficult for the zooplankton to find the phytoplankton and eat them – so more phytoplankton survive and populations begin to increase during the dark, cold days of winter.”
    There is so much wrong with this one sentence.
    A grade school science project, and it passed peer………………
    No I take that back, don’t want to insult grade schoolers

  24. latitude
    July 17, 2010 at 10:14 am
    Is zooplankton metabolism more dependent on temperature then phytoplankton, that is could a decrease in activity of the zooplankton in mid winter while phytoplankton activity remains more constant be an explanation for the increase in abundance? Have you read the paper, what do you think? I scanned it pretty fast as I do not really have the time to dig into it yet. It looked like the authors were more interested in the measured depth of the mixing layer rather then attributing a cause for the mixing, until the last obligatory for the press AGW reference. On the other hand, I did not see any discussion of the effects of temperature on zooplankton.

  25. Whether or not this paper is correct, I get the feeling that the government is trying to find as many bad things from AGW as possible. Goldman Sachs must be getting antsy at not having those cap-and-trade profits.

  26. As for ocean stratification in the past. Yes, it has happened, but only rarely, for relatively short periods, and when the climate was vastly warmer than now. The last time was about 100 million years ago in the mid-Cretaceous. The Paleocene-Eocene Thermal Maximum (PETM) was apparently not warm enough and/or not long enough to cause stable stratification, despite sommer SST:s about 20 degrees centigrade near the North Pole.

  27. In my personal view, the credibility of any scientific study takes a big nose-dive if those results are cited as a reason for being concerned about anthropogenic global warming/climate change — especially if that was the primary justification for conducting the investigation in the first place.
    I believe, however, there is a possibility that our medium scale climate fluctuations — Little Ice Age and Medieval Warming — might be the result of natural predator-prey, global-population cycles between zooplankton and phytoplankton. Other than contributing to the CO2 cycle, I speculate that the quantity of these creatures may have a direct effect on the amount of solar energy absorbed by or reflected off the ocean.

  28. As winter storms become more frequent and intense, the biologically-rich surface layer mixes with cold, almost clear and lifeless water from deeper levels.
    Oh, noes! All the benthic fauna has gone extinct?
    “It’s worse than we etc…”

  29. Someone, or some entity, is certain to fund this professor, whom I am sure has made it clear that accurate conclusions on this subject require at least 20 years of intensive study of the data, which should take him comfortably through to retirement.
    If he succeeds in convincing people that his unfounded scare story about linking increased winter storms to the possible collapse of the phytoplankton population, and blaming it on global warming, then good luck to him – give him full marks for knowing how to milk the system with BS. Just don’t forget to pity the poor guys who have to pay for his studies, which is all of us.

  30. Archonix says:
    July 17, 2010 at 10:53 am
    “If warming causes more storms then it cannot also cause more stratification.”

    This is why I called it a crock! We have been told about increased INTENSITY and FREQUENCY of future storms under AGW. Now we are being led to believe that it will not be enough to prevent stratification!!!!!
    I have no issue with the first part of the press release. However, they then tack on AGW in order to secure future funding. Now let’s spot the weasle words relating to ‘future warming’ assumptions.
    “expected to become warmer” “could lead” “suggests”
    The appeal more for funds are here:
    “more research and observation will be needed”
    Had the bit about global warming not been added he would have struggled to get more funding.

  31. @latitude: Don’t be so reticent. Let us know how you really feel about this theory. Be a latitude with attitude.

  32. DesertYote says:
    July 17, 2010 at 11:44 am
    Is zooplankton metabolism more dependent on temperature then phytoplankton
    ==========================================================
    no
    Without using words I can’t spell any more, they made the stupidest grade school mistake.
    What zoo?
    What phyto?
    They act like no one knows that phyto “surges” in the winter, then don’t say what phyto, and don’t say if it’s the same one in summer – it’s not.
    Most of the zoo population reproduces seasonally, but they don’t define what zoo they are talking about either. rotifers? baby jellyfish? what? most are temperature dependent, and again, the zoo population will consist of vastly different zoos different times of the year.
    This paper went through the peer process, which means most of the spelling and punctuation was corrected…
    …that’s all.

  33. tty says:
    July 17, 2010 at 11:57 am
    “As for ocean stratification in the past. Yes, it has happened, but only rarely, for […]”
    Thanks, tty!

  34. carrot eater says:
    July 17, 2010 at 11:13 am
    “How long do you expect such effects from a single storm to last, after all?”
    AGW state and increase in frequency and intensity of storms. I hope you can see the contradiction in the report. For most here it was glaring. Or is everything possible under global warming!!!! AGW is on spindly legs and its proponents are bending over backwards to keep it upright.

  35. Following tty’s hinat at the Cretaceous, i looked it up on the wikipedia, and following a link to the “Cool tropics paradox” – poles were ice-free and GCM’s computed very hot tropical temps in the Cretaceous. Proxies OTOH pointed to cooler tropics.
    Well, they fixed that by adjusting the proxies.
    Watch in horror:
    http://en.wikipedia.org/wiki/Cool_tropics_paradox
    If only these people would just do their thing silently and not constantly open their mouths talking about the future…

  36. tty says:
    July 17, 2010 at 11:57 am
    As for ocean stratification in the past. Yes, it has happened, but only rarely, for relatively short periods, and when the climate was vastly warmer than now. The last time was about 100 million years ago in the mid-Cretaceous.
    ========================================================
    tty, look at a map of where they think the continents were during the Cretaceous.
    Look at the map and see where we would still be able to find records of stratification.
    And then think about why we would believe that.
    hint – Mississippi river

  37. latitude says:
    July 17, 2010 at 10:14 am
    I am embarrassed to say it but this is my field.

    We all have our crosses to bear…
    Whens zoos are abundant, it’s because their food is abundant, not the other way around.
    This makes sense. To me at least. Though that’s not to suggest that makes it a concensus.
    They obviously need to get new books, they are reading Chemical Oceanography by Frank Millero. That book is an embarrassment to everyone in this field and people that do not know any better claim it’s the bible.
    They don’t seem to cite this anywhere – what gives it away?

  38. This cycle is like the wolf/rabbit boom and bust which I observed in Alaska around 1970 although that cycle was not an annual cycle.
    The zooplankton consume the blooming phytoplankton and increase in numbers. By the end of the summer the zooplankton run out of phytoplankton, the zooplankton stop reproducing, and die off. The few remaining phytoplankton begin to increase again in the fall and winter. By the spring the phytoplankton are blooming and the zooplankton begins the cycle again.
    Does there have to be a mixing of warm and cold water?

  39. Z says:
    July 17, 2010 at 1:30 pm
    They don’t seem to cite this anywhere – what gives it away?
    ===================================================
    “That hypothesis, commonly found in oceanographic textbooks”
    Z, this is a ‘trick’ paper.
    First they try to give the impression that the “Critical Depth Hypothesis” is an excepted theory – it is not – and then they go on to take 9 years to try and explain it away. Which they do not even do that.
    The “Critical Depth Hypothesis” is over a 1/2 century old.

  40. Warren, you almost got it all.
    Add phototoxicity, heat stress, nutrient upwellings, through in some biorhythms, and you’re there.

  41. Jimbo,
    “AGW state and increase in frequency and intensity of storms.”
    Even if that were true (and I’m not sure it is, on the frequency), I don’t think it necessarily has the implications you guys are invoking.
    The observed thermocline and halocline are going to fluctuate with conditions, but I don’t see that some increase in hurricane intensity should necessarily play a huge role in those, beyond the area in and around the storm path, and beyond the time period the storm happens to be there.
    If you’re trying to craft some sort of gotcha or claim of inconsistency here, it’s going to take some more work to demonstrate, I think.

  42. DoctorJJ says:
    July 17, 2010 at 9:42 am
    Warming means more storms which means more nutrients and more mixing, so theory FAIL.
    NEXT!!!
    __________________________________________________________
    While I read the article the same “wait a minute” occurred to me in that the basic mantra of AGW is, and I believe always has been ever increasing storms.
    Now a subtle nudge in the opposite direction seemingly suggesting us to ignore the “tidal waves” behind the curtain?
    Okay, with my head hurting, whether GW or AGW, OSU sees a decrease in storms, though not the only mechanism, but surely a major mechanism, as decreasing.
    Got it…………….I think………..indoctrination is really hard on me.

  43. Maybe he’s wrong, maybe he’s right.
    Only really 2 things to do:
    1) Write up a counterexample, debunking the theory.
    2) Support the theory with additional experimentation.
    Not sure what all the armchair science is about here.

  44. “Behrenfeld said that oceans are very complex, water mixing and currents can be affected by various forces, and more research and observation will be needed to fully understand potential future impacts. However, some oceanographers will need to go back to the drawing board.”
    I strongly suspect most of them need to do that including Dr. Behrenfeild. The critical depth hypothesis is not dead and the “dilution-recoupling hypothesis,” has not replaced it. Both appear to be over simplified. What this paper does illustrate is how little the oceanographers know. I suspect they know even less then the climatologists and we know how good their knowledge base is.
    He is absolutely correct in saying “oceans are very complex” and more research is needed. It is not that I do not like remote sensing, it is simply that uncalibrated by real empirical data it is noting short of speculation. Time to get out the “Nanson Bottles” and get to work.

  45. I would like someone with expertise in this field work out for us the ramifications of this theory for specific geographical locations. How far north is Behrenfield looking? Does his theory explain the separation of zooplankton and phytoplankton in Hudson’s Bay, with its highly stratified hydrographic profile? How does his theory work out in relation to the well-mixed waters of the Bay of Fundy and adjacent waters in the Gulf of Maine? The Bay of Fundy’s waters get thoroughly mixed via extreme tides, while Hudson’s Bay is highly stratified due to a brackish surface layer from the many rivers that empty into this body of water. So one does not even need ‘global warming’ to test his hypothesis. Would not phytoplankton and zooplankton go through population cycles independent of the time of year and other factors if extreme stratification occurred? And would not limiting nutrients be an even bigger concern than zooplankton blooms if such stratification persisted?

  46. Scott Basinger says:
    July 17, 2010 at 3:45 pm
    Maybe he’s wrong, maybe he’s right.
    Only really 2 things to do:
    1) Write up a counterexample, debunking the theory.
    2) Support the theory with additional experimentation.
    ======================================================
    Scott, this paper was obviously written by someone that has never been out of a school environment of some kind. This is what is taught in school, from text books that schools use.
    There is nothing to debunk. This paper is trying to debunk a theory that is not an accepted theory in the first place.

  47. Why would mixing of water that does not contain Zs and Ps with water that does contain Zs and Ps make it harder for the Zs to find the Ps? The volume of the water does not change, so they are not swimming across greater distances. Why would mixing not push the Ps and Zs together instead of separating them? Reminds me of Star Wars. Remember the first movie and the explosion of the first Death Star? It went up like a big firework, perfectly symmetric. Then there was the Challenger explosion and we all got an education in what a real explosion looks like. Following that education, when the second Death Star goes up in Star Wars 3 the explosion is asymmetric with big pieces dominating the screen. I wonder if someone is suffering from a failure of imagination?

  48. latitude says:
    July 17, 2010 at 2:05 pm
    Warren, you almost got it all.
    ===================================
    Tank you very much fur yur appraisal, latituude.
    I didn’t tink dat you ver truing in some of dooss biorhythms, but I had to look long and hart to see dat you ver trowing ’em in.
    Varren in Minnisoda (ver ve are gneiss)

  49. This guy has it backwards, the nutrient-rich water is deep within the ocean, and upwelling in the spring enriches the surface, stimulating phytoplankton growth. Global warming has nothing to do with it. Here:
    “What the water samples do tell us is that nutrient availability in the water column changes with the seasons. Winter mixing brings nutrients up from below, concentrating them near the surface. Spring warming creates a surface layer that floats on top, halting the supply of nutrients brought to the surface. As spring turns to summer, nutrients in the surface layer are consumed by phytoplankton, reducing nutrient availability at the surface. As summer sets in, phytoplankton die and drift to the bottom, taking the nutrients they ingested with them. Surface waters are now left with few nutrients available.”
    http://serc.carleton.edu/eet/phytoplankton/primer.html
    ———
    God, I just HATE bad science!!! Grrrr!!!

  50. crosspatch says:
    July 17, 2010 at 10:58 am
    “So, which is it? AGW means more storms? Less storms? A storm free Arctic?”
    Probably whichever validates their meme this week.
    I found this article to be very interesting.
    New findings have revealed that massive amounts of carbon are converted into “inedible” forms of organic carbon that remain out of circulation for thousands of years, effectively sequestering the carbon by removing it from the ocean food chain. According to Jiao Nianzhi, a microbial ecologist here at Xiamen University, the amount stored is tremendous: “It’s really huge. It’s comparable to all the carbon dioxide in the air.”
    ______________________________________________________________
    So Mankind NEEDS to burn inorganic carbon to return carbon to the life cycle as bio-accessible CO2. I always thought so but it is nice to have a “scientist” say so.

  51. DirkH says:10:46 am
    “Even assuming that the “CO2 with water vapor feedback” global warming is taking place in the atmosphere, i doubt that this will have much effect on ocean temperatures.”
    Ah, but the models assume that the CO2 caused warming will cause more clouds to evaporate so the oceans will see more sunlight and the oceans will warm. Of course the warmer ocean will not evaporate more water causing more clouds because um, um, then the carefully tweaked models would not match the historic temperatures. All this is so obvious that warming will cause droughts because it will be like a desert with sunshine all day and we’re all going to cook! The ice core data shows this. The ice layers from cold periods have much more dust from all the deserts showing that cold times were dryer and warm times were wetter with few deserts and therefore the wetter times had fewer clouds because they all turned to rain and you can’t have storms without clouds and then…um. Oh my…. Nevermind.
    Excuse me, I need to go and make some more stuff up. Can I have me some grant money?

  52. No one has mentioned ocean acidification yet. Surely we can get CO2 into the discussion somehow.

  53. Someone needs to pull out the data from the Deep Sea Drilling Program. I am almost certain that we have historic data from sea floor cores that contradict this clowns wothless conjecture that higher global temps means lower bioproductivity in the oceans

  54. [snip – off topic, we have a post cover both the pro and con side of this story, comment there ~mod]

  55. Notice how the …… cold, almost clear and lifeless water from deeper levels.
    provides abundant nutrients for the Anchovy fisherfolk off Peru when the Humboldt current carries nutrient rich deep cold southern water to the surface at Christmas time during La Nina events.

  56. @Keith Minto (July 17, 2010 at 9:29 pm) The upwelling of deep nutrients benefiting the anchovy fishery was my first thought when reading this too.
    Also, large areas of the surface oceans have low productivity due to lack of nutrients – areas of the Pacific – unrelated to temperature as far as I know. On the other hand the paper is assuming the deeper layers are devoid of nutrients because there is less life, when in fact in productive regions productivity at depth is probably light and not nutrient limited. Vertical mixing will then tend to be beneficial IF there is any relative nutrient depletion in the surface layers.
    The top 100 metres sunlit (euphotic) zone where 70% of the world’s photosynthesis takes place is the most productive zone for phytoplankton . Zooplankton are well known to have a Diel Vertical Migration within that zone – rising at night to access the more phytoplankton-abundant layer.
    It is well known also that many marine plants (from phytoplankton to seaweeds) actually start their growth cycle in the winter.

  57. “And they also raise concerns that global warming, rather than stimulating ocean productivity, may actually curtail it in some places.”
    http://www3.interscience.wiley.com/journal/118811203/abstract?CRETRY=1&SRETRY=0
    There was a discovery in the last few of years of a newly found type of phtoplankton, which they estimated to be responsible for at least 60% of uptake of co2 in the carbon cycle.
    Winter storminess in the English records show more gales at a rise in temperature in winter months, but as this is to do with short term temeperature diffentials, it has not a lot to do with longer term temperature trends.
    http://booty.org.uk/booty.weather/climate/histclimat.htm

  58. Both theories are partly wrong.
    1. The winter storms mix deep ocean water, biologically poor but nutrient rich, with the biologically rich and sun lit but nutrient poor surface waters. Light levels are less important than nutrients. This is why up-welling pumps and fertilisation produce blooms.
    2. Some of the phytoplankton are also zooplankton depending on the stages of their life.
    3. The theory also does not deal with the vertical mobility of most planktons. They can move many meters in a day. So mixing should not have a diluting effect longer than a few days.
    4. Most phytoplankton are viable reducers feeding on dead things so they can survive in the darker depths but don’t reproduce fast.
    5. Storms also oxygenate the water so blooms can grow faster and bigger with out stripping the surface water of oxygen and causing Oxygen starvation and the crash of the bloom to a dead zone goop. Note because of point 4 the goop is not always dead. Unfortunately digestive agents used by these reducer algae make the goop toxic.
    6. 90% of the rain in both hemispheres is seeded by dimethyl sulphide secreted by phytoplankton in the mid and upper latitudes. the chemical protects the organisms from salt. Because its a response to salt production rates decrease in fresher waters. I.E. after rain has freshened the surface waters. There’s probably another feed back there.
    All this was taught in High School in the late 1970’s. Why was it on the Australian curriculum then and is unknown today?

  59. “90% of the rain in both hemispheres is seeded by dimethyl sulphide secreted by phytoplankton in the mid and upper latitudes.”
    So more co2 and more iron in the oceans feeding blooms, makes more DMS?

  60. Interesting but data heavy site on phytoplankton blooms http://oceancolor.gsfc.nasa.gov/cgi/image_archive.cgi?c=CHLOROPHYLL
    Note the first image with the caption
    A break in the clouds over the Barents Sea on August 1, 2007 revealed a large, dense phytoplankton bloom to the orbiting MODIS aboard the Terra satellite. The bright aquamarine hues suggest that this is likely a coccolithophore bloom. The visible portion of this bloom covers about 150,000 square kilometers (57,000 square miles) or roughly the area of Wisconsin.

    The coccolithophores are linked to DMS/cloud production.
    I just like pretty pictures.

  61. “I’m skeptical of the claim made about GW “stratifying the oceans, resulting in less mixing” because as we’ve been told many times, A Warming World Means More Destructive Storms. ”
    Storms aren’t the major driver of oceanic turnover, they’re not powerful and constant enough. It’s the thermohaline circulation originating at the polar regions that does it, which weakens in a warmer world.
    Stratified ocean have occurred in past Greenhouse worlds and palaeontologists love them: the fossil record from the seafloor is awesomely preserved because not even bacteria survive in the anoxic oceans below a few hundred meters.
    Obviously nothing that dramatic will happen in the near furture, but even a slight reduction in ocean turnover can have a significant impact on the food web.

  62. ginckgo says:
    “because not even bacteria survive in the anoxic oceans below a few hundred meters.”
    Nonsense. Haven’t you heard of anoxic and anaerobic bacteria which positively thrive without oxygen? Bacteria that grow in such conditions, some of which produce methane from decaying organic material, include some of the oldest organisms on Earth, evolving before there was oxygen in the atmostphere.

  63. ginckgo says:
    July 18, 2010 at 11:02 pm
    Storms aren’t the major driver of oceanic turnover, they’re not powerful and constant enough. It’s the thermohaline circulation originating at the polar regions that does it, which weakens in a warmer world.
    There seems to be some confusion here – thermohaline circulation is not a factor in the mixing of the water column in the shallow coastal continental plate seas where the most productive fisheries are located. The mixing that Behrenfeld is referring to is driven by winter storm driven winds. His reference to “cold, almost clear and lifeless water from deeper levels” is however misleading and unhelpful, the adjective he forgot to include is nutrient-rich. Without replenishment of nutrients from deep waters the it is the surface layer that becomes clear and lifeless.
    Behrenfeld’s offering can be divided into two parts: firstly, the hypothesis about food particle density and zooplankton grazing dominating the bloom dynamics. Secondly, the AGW epilogue about CO2 and the drearily inevitable warning of warming catastrophe. The author’s AGW epilogue sounds rather perfunctory, he knows it is needed for politics and funding but his heart is not really in it. He is certainly no physical oceanographer / “climatologist” although a very good biological oceanographer.
    His “part 1” hypothesis about zooplankton grazing and food particle density sounds plausible. Although it is perhaps over-ambitious to try to support such a proposed model from satellite data alone. You need to get your hands wet and do some detailed plankton sampling to address these questions of food particle density. This brings back nostalgic memories of my postgraduate research project aboard a “research ship” (recently converted from a French fishing boat) jointly run by marine biology establishments in Plymouth, UK and Roscoff in France. We criss-crossed the boundary of the continental shelf in the Celtic Sea to study makerel larva (Scomber scomber) first feeding and survival, by trying to assess food particle density in the vicinity of the larvae. We deployed the torpedo-like ‘UOR” (undulating oceanographic recorder) which moved vertically in a sine-wave through the water column and automatically sampled plankton in nets at different depths. This was a 24-hour operation – being the student on board I got the “dead man’s shift” i.e. midnight – 4am.
    Fish larval survival is very closely tied to density of food particles near the larva. As fish larvae and all zooplankton get smaller, their foraging range gets less and the water becomes effectively more viscous, requiring more energy to travel through it. So for the smallest zooplankton such as heterotrophic microflagellates which account for a large part of phytophankton grazing, the diatoms and other algae need to be quite close to be an available food item. Larger zooplankton such as the copepods do indeed engage in vertical migrations, but they are not primary phytoplankton feeders, their diet also includes smaller zooplankton.
    So some more detailed water column sampling would be needed to confirm Behrenfelds hypothesis.
    If it is true – as the AGW establishment asserts – that more heat in the climate results in more energy for wind and storms, then this could point to another negative feedback – the increased winds would cause increased water column mixing, bringing more cooler deep water to the surface and opposing the warming effect.

  64. @phlogiston says:
    July 19, 2010 at 4:40 am
    “If it is true – as the AGW establishment asserts – that more heat in the climate results in more energy for wind and storms,”
    In a given month yes, as a trend over decades no, the opposite it would seem by this measure; http://www.aoml.noaa.gov/hrd/hurdat/ushurrlist18512009.txt
    On Jupiter storms are around 400mph, on Neptune they are near the speed of sound.

  65. The author seems to have presented the critical depth hypothesis as a cut-and-dried consensus. But it wasn’t difficult to find articles that addressed short-comings and expanded the theory to critical depth, critical turbulence, community composition, water density and salinity, etc.
    http://aslo.org/lo/toc/vol_44/issue_7/1781.pdf
    http://science-mag.aaas.org/cgi/content/abstract/296/5568/730
    It is hard to tell without looking at this new paper, but it seems a little presumptuous to be claiming that he has overturned anything.
    I am also highly skeptical of the “dilution” idea. If the cold, upwelling water is diluting the plankton concentration, then that must mean that a portion of plankton (zoo and phyto) are being displaced. Where could they go, except further down in the water column, which, especially for the phytos, would mean death?

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