Guest Post by Willis Eschenbach
Following on from Anthony’s article, here are my thoughts about the phytoplankton paper “Global phytoplankton decline over the past century”, by Daniel G. Boyce, Marlon R. Lewis & Boris Worm.
I started to write about this earlier, but I decided to wait until I had the actual paper. The paper in question is behind a paywall at Nature Magazine, but through my sub-oceanic channels (h/t to WS) I have obtained a copy. The paper makes two main claims, that: a) the numbers of phytoplankton have been cut by more than half since 1900, and b) the general warming of the global oceans is the reason for the declining numbers of phytoplankton.
First, what are phytoplankton when they are at home, and where is their home? Plankton are the ubiquitous soup of microscopic life in the ocean. Phytoplankon are the plant-like members of the plankton, the ones that contain chlorophyll and feed on sunshine. Phytoplankton are to the ocean what plant life is to the land. Almost all oceanic life depends on phytoplankton. Other than a thin strip of seaweeds and sea grasses along the coasts, phytoplankton are the microscopic plants that are the foundation of the vast entire oceanic food chain. Without phytoplankton there would be no deep water oceanic life to speak of. Figure 1 shows where you find phytoplankton:
Figure 1. Global distribution of phytoplankton. Lowest concentration is purple and blue, middle concentration is green, highest concentration is yellow and red. Source http://www.nasa.gov/vision/earth/environment/0702_planktoncloud.html
So where did the Nature paper go wrong?
The short answer is that I don’t know … but I don’t believe their results. The paper is very detailed, in particular the Supplementary Online Information (SOI). It all seems well thought out and investigated … but I don’t believe their results. They have noted and discussed various sources of error. They have compared the use of Secchi disks as a proxy, and covered most of the ground clearly … and I still don’t believe their results. Here’s exactly why I don’t believe them.
This is their abstract (emphasis mine):
In the oceans, ubiquitous microscopic phototrophs (phytoplankton) account for approximately half the production of organic matter on Earth. Analyses of satellite-derived phytoplankton concentration (available since 1979) have suggested decadal-scale fluctuations linked to climate forcing, but the length of this record is insufficient to resolve longer-term trends.
Here we combine available ocean transparency measurements and in situ chlorophyll observations to estimate the time dependence of phytoplankton biomass at local, regional and global scales since 1899. We observe declines in eight out of ten ocean regions, and estimate a global rate of decline of ~1% of the global median per year. Our analyses further reveal interannual to decadal phytoplankton fluctuations superimposed on long-term trends. These fluctuations are strongly correlated with basin-scale climate indices, whereas long-term declining trends are related to increasing sea surface temperatures. We conclude that global phytoplankton concentration has declined over the past century; this decline will need to be considered in future studies of marine ecosystems, geochemical cycling, ocean circulation and fisheries.
The first clue to where they went wrong is visible in Fig. 1. Although as you can see there is more phytoplankton in the cooler regions of the north, the same is not true in the corresponding regions in the south despite the ocean temperatures being very similar. In addition, there are many places where the ocean is warm (e.g. tropical coasts) that have lots of phytoplankton, while in other warm areas there is very little phytoplankton.
The rude truth of phytoplankton is this: phytoplankton growth is generally not limited by temperature. Instead, it is limited by nutrients. Where nutrients are plentiful, the phytoplankton grow regardless of temperature. Nutrients are more common along the coastline, where sub-oceanic currents come to the surface bringing nutrients from the deep ocean floor, and rivers bring nutrients from inland. For example, in Fig. 1 you can see the nutrients from the Amazon river causing the red area at the river mouth (north-east South American coast).
Indeed, the fact that phytoplankton are generally nutrient limited rather than temperature limited has been demonstrated in the “ocean fertilization” experiments using rust. If you spread a shipload of rust (iron oxide) out into the tropical ocean, you generally get an immediate bloom of phytoplankton. Temperature is not the problem.
So to start with, the idea that increasing temperature automatically leads to decreasing phytoplankton is not generally true. There are vast areas of the ocean where higher temperatures are correlated with more phytoplankton. For example, the warmer deep tropics generally have more phytoplankton than the cooler adjacent subtropics.
The paper’s most unbelievable claim, however, is their calculation that since 1899, the density of phytoplankon has been decreasing annually by 0.006 milligrams per cubic metre (mg m-3). They give the current global density of phytoplankton as being 0.56 mg m-3. Thus they are claiming that globally the concentration of phytoplankton has dropped by more than 50% over the last century.
Now, a half century ago I learned to sail on San Francisco Bay. Since then I’ve spent a good chunk of my lifetime at sea, as a commercial fisherman from California to the Bering Sea, as a sailboat delivery crewman, as a commercial and sport diver, and as a surfer. And call me crazy, but I simply don’t believe that the sea only has half the phytoplankton that it had in 1900. If that were true, it would not take satellites and complex mathematical analysis to show it. People would have noticed it many years ago.
I say this because phytoplankton are the base of almost the entire mass of oceanic life. They are what almost all other life in the ocean ultimately feeds on, predators and prey as well. The authors of the study do not seem to realize that if the total amount of phytoplankton were cut by more than half as they claim, the total mass of almost all living creatures in the open ocean would be cut about in half as well. No way around it, every farmer knows the equation. Half the feed means half the weight of the animals.
And I see no evidence of that having happened over the last century. It certainly does not accord with my own extensive practical experience of the ocean. And I see no one else making the claim that we only have half the total mass of deep-water oceanic life that we had a century ago..
The other thing that makes their claimed temperature/phytoplankton link very doubtful is that according to the HadISST dataset, the global ocean surface temperature has only increased by four tenths of a degree C in the last hundred years.
Four tenths of a degree … an almost un-noticeable amount. Yet their paper says (emphasis mine):
Our analyses further reveal interannual to decadal phytoplankton fluctuations superimposed on long-term trends. These fluctuations are strongly correlated with basin-scale climate indices, whereas long-term declining trends are related to increasing sea surface temperatures.
These kinds of claims drive me nuts. Is there anyone out there that truly believes that a change of global average ocean temperature of four tenths of a degree C over the last hundred years has cut the total mass of phytoplankton, and thus the total mass of all oceanic creatures, in half? Really?
So that’s why I say I don’t know where their math went wrong, but I don’t believe their results. I don’t believe we’ve lost about half the total mass of all oceanic creatures. Half the planet’s open ocean dwellers? Where is the evidence to support that outrageous claim? And I don’t believe that an ocean temperature change of four tenths of a degree over a century has made much difference to phytoplankton levels, as they grow at all temperatures.
Why don’t I know where their math went wrong? Unfortunately, they have not posted up the data that they actually used. Nor have they shown any of their data in the form of graphs or tables. Instead, they have shown model results, and merely pointed to general websites where a variety of datasets are maintained. So we don’t know, for example, whether they used the 1° grid version or the 2.5° grid version of a given dataset. Nor have they posted the computer code that they used in the analysis. Plus, the very first link in their paper to the first and most important data source is dead.
Grrrr … but dead link or not, pointing to a website as the data source in their kind of paper is meaningless. To do the analysis, they must have created a database of all of the observations, with the meta data, and the details for the type etc. for each observation. If they would include that database and their code in the SOI, then someone might be able to figure out where their math went wrong … my guess is that it may be due to overfitting or misfitting of their GAM model, but that’s just a wild guess.
It is a shame that they did not post their data and code, because other than the lack of data and code it is a fascinating analysis of a very interesting dataset. I don’t accept their analysis of the data because it doesn’t pass the “reasonableness” test, but that doesn’t mean that the dataset does not contain valuable information.
[Update] An alert reader noted that the image in Figure 1 was of a particular month and not a yearly average. So I’ve made a short movie of the variations in plankton over the year.
Figure 2. Monthly movie of plankton concentrations. Click on image to see animation.
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dh7fb says:
August 1, 2010 at 1:03 am
I’m glad it’s a typo. For a second there, I thought Elmer Fudd had become a warming alarmist.
In the above-mentioned transcript of interview in radio
http://www.dradio.de/dlf/sendungen/forschak/1236178/
the author ascribes diminishing phytoplankton to lesser mixing of the ocean water layers – the surface layer with plankton is a bit warmer due to global warming and suchlikes, therefore it mixes less with the colder lower layer containing nutrients (due to bigger temp difference between them). Apparently he thinks that the lower layer does not get any of this warming and stays as cold as it always was. Does that make sense in physics? When we are told that the missing GW heat lurks hidden somewhere deep in the oceans in a pipeline?
Wow, is this a can of worms.
Reverse causation. Does the plankton change albedo and hence temperature?
(Classically I quote http://dnacih.com/SILVA.htm)
Predator-prey maths. Examples of cyclic food supplies abound in the literature.
A random pick, http://www.math.unl.edu/~jlogan1/PDFfiles/BMBpaper2008.pdf
Nutrition. It’s not just iron. Phosphate can be limiting also. Probably half a dozen more nutrients. Note the higher abundance of plankton globally at the edges of continents, especially near heavy habitation, especially where soil runoff adds nutrients to the ocean. Dare one say that rising sea levels will meet fresh and more nutrients?
etc etc.
Ziiex Zeburz says:
August 1, 2010 at 3:16 am
A little unclear. Do you mean the underground temperature hardly changes? As an aside, this has implications dor dendroclimatology, because people don’t often report temperature changes in the root zone of plants, a zone that can influence tree rings.
Willis,
You show once again, the collapse of the “Peer-Review” system. Must be hard up to sell magazines without tanted science.
The problem is that governments and individuals use this garbage science as leverage for whatever policy they dream up and also for grant monies. Look at IPCC (peer-reviewed science).
Need an FBI type system:
Facts mam, nothing but the facts.
Friends:
I have an interest in this.
In the 1980s there was an ‘acid rain’ scare in Northern Europe. It was claimed that sulphurous and nitrogenous emissions from coal-fired power stations (notably in the UK and Germany) were increasing the acidity of rain with resulting waldsterben (i.e. forest death) especially in Scandinavia and Germany.
This was extremely unlikely for several reasons. For example, the highest atmospheric concentrations of the emissions must be adjacent to the power stations, and the emitted oxides of sulphur and nitrogen (SOx and NOx) are very soluble in water. Therefore, the asserted increased sulphur deposition in rain (and damage to plants) should be greatest near the power stations, but there was no significant increase to sulphur deposition near power stations (and there was no discernible damage to plants adjacent to the power stations).
However, France had converted its electricity supply industry to be mostly nuclear. Constraint of SOx and NOx emissions from power stations would significantly increase UK and German electricity costs – with resulting increase to all UK and German industrial costs – relative to those of France. Also, Scandinavian countries desired reparations for the asserted damage to forests.
The European Union (EU) established its Large Combustion Plant Directive (LCPD) in response to the ‘acid rain’ scare, and the LCPD continues to close coal-fired power stations and to disrupt European energy policies to this day.
At the time, I was working at the UK’s Coal Research Establishment (CRE) that was owned by the UK government as part of the National Coal Board (NCB). I observed that the pattern of acidity of precipitation over Northern Europe was not consistent with the ‘acid rain’ scare. Highest acidity was in rain near estuaries of major rivers. Indeed, if the emissions from power stations were to reach Scandinavia then they had to cross such regions of high acidity in rain, and this did not make sense.
I suggested that a more likely explanation for increased sulphur content of rain was fertilisation of the North Sea by excess nitrate and phosphate fertilisers being used in agriculture. The excess would be transported by rivers to the North Sea. Resulting fertilisation of phytoplankton may be increasing their total biomass with resulting increase to their emission of dimethylsulphide (DMS). This suggestion was supported by the growth of toxic algal blooms that were washing up on shores of the North Sea at the time. And the suggestion would completely explain the observed pattern of increased sulphur deposition in rain across Northern Europe.
Upon investigation the suggestion turned out to be correct.
So, farmers – not electricity generators – were causing the increased sulphur content of rain. And, at the time, farmers were a powerful lobby in France. So, constraints were imposed on
(a) the use of excess fertiliser and
(b) permissible nitrate and phosphate in rivers.,
Then the ‘acid rain’ scare was quietly forgotten.
Furthermore, it subsequently became clear that biomass of Northern European forests had increased throughout the 1980s when the ‘acid rain’ scare raged and the existence of waldsterben was asserted.
But the LCPD remains and continues to harm energy policies.
The history of the ‘acid rain’ scare is a warning now that the ‘global warming’ scare is ending. Neither scare has been – or will be – declared over. The ‘acid rain’ scare was quietly forgotten, and the ‘global warming’ scare will be quietly forgotten after its last gasp in Mexico later this year.
And – like the ‘acid rain’ scare – the ‘global warming’ scare can be expected to harm energy policies for decades after it is forgotten.
Richard
The authors of this study did not study the mechanisms that may have lead the decline in phytoplankton abundance and growth. However, they know that phytoplankton grow quickly at warm temperatures when supplied with sufficient nutrients and light. Thus, if asked, they would suggest that the decline in phytoplankton was due to the effects of warming on ocean circulation, thermal stratification and vertical (with depth) mixing. These are the same temperature effects observed in the el Nino/la Nina comparisons and the lower productivity of tropical oceans compared to higher latitudes.
Such effects of climate warming have been readily documented in large, deep lakes around the world (see for example, the special climate/lake issue of Limnology and Oceanography, December 2009). Most paper in this issue are open access due to fees paid by the authors; at http://www.also.org). Note that warming during the late winter, early spring period has the most impact on thermal stratification, so the overall mean temperature change is not that relevant.
A 40% decline in mean phytoplankton would not be easily detected by Willis’ anecdotal observations, since seasonal changes are often several hundred percent at one site and his observations are presumably focused on the spatially highly variable coastal waters. A 40% decrease in phytoplankton would not lead to a proportionate change in higher food chain organisms, because lower phytoplankton abundance usually leads to higher turnover. Many large fish, such as bluefin tuna have been reduced by >90 by over fishing, so we cannot use fish as a proxy for phytoplankton. Detecting these changes in phytoplankton needs to be based on real data, not perceptions.
Note that iron limitation is mainly a factor in the South Pacific. Quite a number of publications concluded that continuous iron fertilization over vast expanses of the ocean would be an expensive and not feasible way of increasing CO2 sequestration, for a number of reasons that I don’t have time to discuss.
Scientists already had good evidence for long term declines in phytoplankton abundance. This paper shows that the decline is stronger, more pervasive and more consistent than expected. I do not find anything in Willis’ perceptions and anecdotal observations that are serious criticism of the massive amounts of data presented in this publication. Clearly, this study will stimulate more research and more data collection and analysis. To evaluate the hypothesis, we need data, not perceptions.
Hard Numbers and Anecdotal Stuff
I know a place where anyone can get some hard numbers on the state of the food chain in the tropics. I lived in the tropics (Puerto Rico) for the first 20 years of my life and visited there on a monthly basis up until about 5-years ago. I have fished the waters off Puerto Rico since I was six, that’s a 45-year timeline, subtracting the last 5-years.
We sport fished, mostly for Blue Marlin, one of the top pelagic predators in the oceans. It seems obvious that these top of the food chain predators would suffer greatly if the food chain broke down – it never has. Read on.
Since 1953, the Yacht Club in San Juan (Club Nautico de San Juan) has hosted a now famous yearly international tournament. It is the longest consecutively held billfish tournament in the world. Very strict statistics have been kept during that time, after all this is a competitive sport, on all things like strikes per boat, hookups, releases, landings, you name it. This is a rich database on the presence of Blue Marlin off the coast of Puerto Rico and always at the same time of year – September – when the tournament is held.
My personal anecdotal observations: There was a time in the late sixties and early seventies when the fishery almost disappeared. The reason: Longliners. During that time, Blue Marling caught on longlines in the Caribbean numbered in the hundreds of thousands per year. Once the catch numbers plummeted it became unprofitable and the longliners left. It took a long number of years for Blue Marlin to return in numbers. The numbers in the last ten or so years are nothing short of outstanding, with many records broken for the number of fish per boat tagged and released in the tournaments.
The point is, nothing seems to be wrong in the tropics with the food chain. It’s not only Blue Marlin either, Most every (sport) pelagic fishery in the Caribbean is an at all time high. And the tournament statistics prove this.
And yes, the water there is still nutrient rich from upwelling and rivers. As a matter of fact, sportfishing boats always target the “veril”, the Spanish word for the near-coastal water color change. It is an easily visible color change line that separates the nutrient-rich, green colored coastal waters from the sterile, Deep Ocean blue current. When this color change coincides with the 100-fathom line (called “the drop” because depth drops to a couple of thousand feet in less than an eighth of a mile, and where the upwelling occurs), the sportfishing boats will concentrate there.
Club Nautico de San Juan website and history:
http://www.nauticodesanjuan.com/80.html
Alan Mitchell makes an interesting point about polaroid sunglasses. Maybe there is a more general point: the quality of people’s eyesight (with or without glasses) may have improved over this period. People have more frequent eye tests and get new glasses more often; glasses are scratch- and glare- resistant; people who are reluctant to wear glasses can get contact lenses, and so on. It certainly would not be safe to assume that the quality of eyesight is a constant over time. There is also the possibility of differences in the population of observers: if in 1900 they were mainly myopic middle-aged professors, while now they are keen-eyed graduate students, that would make a difference to the results. This is all just amusing speculation, but it highlights the need for more direct checks on the validity of the optical tests.
Julian Flood says:
August 1, 2010 at 12:51 am
……I like this paper. It says, although its authors may not realise this, that the C isotope changes might not be anthropogenic. That great pillar of AGW deserves to be checked and the reasoning behind its inclusion in the great scare should be questioned.
___________________________________________
As you stated in the last post on plankton:
“The C13 vs C14 isotope absorption is related to C3 vs C4 type plants. “C4 uses much more C13/14 than C3.”
A bit of googling shows this:
Carbon-13. C3 and C4 plants.
Terrestrial vegetation and marine phytoplankton, in the process of photosynthetic absorption of CO2, discriminate against heavy molecules perfering 12C to 13….
Most plants (85%) (e.g. trees and crops) follow the C3 photosynthesis pathway and have lower values of d13C, between -22‰ and -30‰.
The remaining 15% of the plants are of type C4. The majority are tropical herbs and have high values of d13C, between –10 ‰ and –14 ‰…. (There is also a third, very minor, group called CAM, a combination of C3 and C4 where some cactus and succulents belong to.)
http://wc.pima.edu/Bfiero/tucsonecology/plants/plants_photosynthesis.htm
examples:
C3—–>wheat, barley, potatoes and sugar beet. (most of the plants are C3)
C4—–>fourwing saltbush, corn, many of summer annual plants.
CAM—> cactuses,some orchids and bromeliads
The other sciencific discovers show that the Carbon isotope picture is not as clean as the CAGW crowd would have us believe. The logic is fossil fuels contain very little 13C and therefore CO2 emissions from fossil fuels is diluting 13C relative to 12C.
14C in Fossil fuels, This is a general article with links about the contamination of coal by subterranean bacteria: http://www.talkorigins.org/faqs/c14.html
There is also evidence that 13C declined sharply in the early Holocene.
A distinct δ13C decline in organic lake sediments at the Pleistocene-Holocene transition in southern Sweden
ABSTRACT: http://www3.interscience.wiley.com/journal/119978862/abstract
“Values of δ13C obtained from conventional bulk sediment radiocarbon dates encompassing the Pleistocene Holocene boundary have been compiled and plotted against 14C age…. A significant decrease in δ13C values, initiated shortly before 10.000 RP and amounting to 5%, is distinguished…. A probable explanation for the δ13C decline in organic material is decreased importance of dissolution of silicates at the transition to the Holocene. During the Late Weichselian. extensive weathering of exposed minerogenic material with subsequent input of bicarbonate to the lake water may have caused a relative enrichment of 13C in dissolved inorganic carbon. Furthermore, the early Holocene increase in terrestrial vegetation cover probably led to an increased supply of 13C depleted carbon dioxide to the lake water by root respiration….”
Evidence from early Holocene speleothems: http://adsabs.harvard.edu/abs/2005E%26PSL.230..301W
“…Delta 13C values were high until 17.79 ka after which there was an abrupt decrease to 17.19 ka followed by a steady decline to a minimum at 10.97 ka. Then followed a general increase, suggesting a drying trend, to 3.23 ka followed by a further general decline. The abrupt decrease in δ-values after 17.79 ka probably corresponds to an increase in atmospheric CO2 concentration, biological activity and wetness at the end of the Last Glaciation…”
Chiefio covers more points here: http://chiefio.wordpress.com/2009/02/25/the-trouble-with-c12-c13-ratios/
As usual there is evidence that refutes the pat answers given by the CAGW champions.
Doesn’t the use of a mercator map distort the percentage of green to blue creating a false image to a casual observer? Maybe intentional?
“Why don’t I know where their math went wrong? Unfortunately, they have not posted up the data that they actually used. Nor have they shown any of their data in the form of graphs or tables.”
So you pay up for such an article and get …nothing. I don’t think Nature’s business model will work out in the long run…
Pat Frank says:
August 1, 2010 at 12:22 am
“It’s a little known fact, for example, that predation, birth defects, and disease were not present among humans before we committed agriculture; a sin unforgivable by Gaia and meriting her punishment; our fallen state only proved by a perverse and decadent love of electricity.”
love it.
S.E.Hendriksen says:
August 1, 2010 at 3:02 am
Phytoplankton has at least two (2) defense systems
Thanks! True! and nature provides more. And the systems you mention are a result of adaptation.
Where is Darwin in this discussion?
The biotic potential of these critters is HUGE! They have ‘morphed’ millions of times in 100 years. The mere fact that they exist in all temperature regimes in many concentrations, is proof in itself that temperature is not the limiting factor of population.
I would think we could pretty easily test this premise in a lab somewhere, where all variables are controlled. It only took a few generations of houseflies (20+/- days) to produce a strain resistant to DDT.
Just observational logic as most are presenting here says “Temp ain’t it!~ look elsewhere!”
Willis, from the link under your map:
Image to right: Phytoplankton can be identified by satellite through their chlorophyll (light green). This image is a composite from the Northern Hemisphere spring seasons of 1998-2004. Click on image to enlarge. Credit: NASA/GSFC and ORBIMAGE
Note, it is spring season in the north.
Fro the AIRS CO2 animation we see the breathing of the earth alternating between hemispheres.
I am almost sure that a corresponding map with the spring time composite of the southern hemisphere would show plankton in the southern seas too.
p.s. which would go to show that increasing temperatures create more phytoplankton, but what weight have real data to compare to model outputs? A generation of “scientists” has come up that believes models trump data.
The simplest explanation is usually the correct one. I don’t think whales could harvest enough Phytoplankton fast enough to make a dent in the population. Temperature is obviously not the answer. Fishery collapse might have some sort of negative feedback affect, but that’s not simple. Sunlight reduction isn’t it. We would have noticed. I go with the Polaroid sunglasses theory. Perhaps combined with ship deck height change over time. It’s pretty obvious that it’s a measurement problem, not a phytoplankton population problem.
If I was this guy’s thesis professor, I would be ashamed to see this paper and make the student do it over. I would certainly not allow it into print because it proves the skeptics are correct, the science is shoddy. Everything is linked to CAGW with not attempt at scientific methodology or looking at any other possible explanations.
I do not have to be a PhD in the field but I come up with some questions for this student just off the top of my head with no digging:
1. Could the correlation be linked to the Milankovitch cycle?
Solar energy reached a summer maximum (9% higher than at present) ca 11 ka ago and has been decreasing since then, primarily in response to the precession of the equinoxes.
2. Do the “short”-term variations in solar radiation at Earth’s surface (S) were observed to increase from 1983 to 2001 have an effect: http://www.sciencemag.org/cgi/content/abstract/sci;308/5723/850
3. Do the 60 to 70 year multidecadal cycles in the
oceans have an effect:
http://icecap.us/docs/change/ocean_cycle_forecasts.pdf
4. Have you taken into account the challenges to the ocean Conveyor Belt Theory?
Deconstructing the Conveyor Belt:
http://www.sciencemag.org/cgi/content/abstract/328/5985/1507
Abstract
“For the past several decades, oceanographers have embraced the dominant paradigm that the ocean’s meridional overturning circulation operates like a conveyor belt, transporting cold waters equatorward at depth and warm waters poleward at the surface…. A number of studies conducted over the past few years have challenged this paradigm by revealing the vital role of the ocean’s eddy and wind fields in establishing the structure and variability of the ocean’s overturning…”
5. How about the observed 88 year and 200 year oscillations that change the nutrients levels from the land:
http://bprc.osu.edu/Icecore/lgt-sci-98.pdf
NASA Finds Sun-Climate Connection in Old Nile Records: http://www.jpl.nasa.gov/news/features.cfm?feature=1319
“The researchers found some clear links between the sun’s activity and climate variations. The Nile water levels and aurora records had two somewhat regularly occurring variations in common – one with a period of about 88 years and the second with a period of about 200 years.”
6. The amount of rain not only effects the river levels, but as the 1930’s dust bowl showed it effects the land and can mean a major influx of nutrients from wind blown soil. Have you taken into account these giant dust storms?
In a round about way, they just said that the worlds oceans are becoming limiting in iron and phosphorus.
Which means the oceans are getting cleaner.
Which means the oceans are releasing CO2.
Which could explain the rise in CO2 levels.
I am thinking here that they may have it wrong entirely about the the warming of the oceans having something to do with dwindling figures of plankton/
If the plankton content is going down, then I suspect it is to do with the acidity and salinity – possibly also the COD demand – and this is from all our desalination and industrial processes. At the end of the day, all our waste water does end up in the sea, also a lot of the carbon dioxide that we put up in the air (as carbonates)
Geoff Sherrington says:
August 1, 2010 at 4:46 am
Nutrition. It’s not just iron. Phosphate can be limiting also.
=======================================================
Exactly Geoff, that’s why just throwing iron out there doesn’t work.
DirkH says:
August 1, 2010 at 6:54 am
“Why don’t I know where their math went wrong? Unfortunately, they have not posted up the data that they actually used. Nor have they shown any of their data in the form of graphs or tables.”
Look here: http://www.nature.com/nature/journal/v466/n7306/fig_tab/nature09268_F4.html
and search the statistical significance! 🙂
Since when did 2 graphs travelling in the same direction prove that one caused the other? The entire global warming science appears to be either identify any slow moving trend which can be claimed to be bad and state it is caused by global warming because of correlation or get separate scientists to tweak parameters to separate models and publish only the worst possible bits out of each run – to give the impression each one is new research and give a cumulatively bad impression to the public – and apparently a consensus of scientists believe in something or other which is never quite clear, so it must all be good science. Do university degrees in the environmental sciences come free with bio-cornflakes?
The high phytoplankton areas seem to be correlated with those that were glaciated 12K years ago — Perhaps the loess runoff is still fertilizing the adjacent waters.
Douglas Cohen says:
August 1, 2010 at 1:29 am
I’ll bet that at the beginning of the twentieth century there was a lot of organic pollution discharged from large cities near the coasts of the developed world. This sort of ocean fertilization probably led to local and large increases in the phytoplankton right off the coast, which may also be where most of the secchi disk and other phytoplankton measurements took place during the early years of the twentieth century. If this is so, I suspect that the decades-long time series on which the supposed drop of phytoplankton is based may be measuring nothing more than the drop in coastal pollution as the developed world’s sewage systems improved..
______________________________________________________________________
And to follow that idea ships follow “shipping lanes” and discharged sewage into the ocean. The Age of Sailing Ships ended with the emergence of the Steam ship in the second decade of the Twentieth Century. The last commercial sailing ship to round Cape Horn was in 1949. Sailing ships would take much longer to make the passage and were constrained by the wind patterns.
Now there are laws….
Vessel operators need to be aware of the following regulations for waste, oil and trash disposal that apply to both federally controlled and state waters. The Refuse Act prohibits throwing, discharging or depositing any refuse matter of any kind (including trash, garbage, oil, and other liquid pollutants) into the waters of the United States.
“…international regulations for the prevention of sea pollution by sewage from ships became effective from August 1,according to a statement from the International Maritime Organisation (IMO). The revised Marpol Annex IV regulations are considered important because the discharge of raw sewage into the sea can create a health hazard,the IMO statement said. In addition, in coastal sea areas, the waste material can lead to a depletion of oxygen in the water and visual pollution – a particular problem for countries with much tourist industries. The revised regulations prohibit the discharge of sewage by ships within a distance of 12 nautical miles,…” http://www.best-maritime-employment.info/catalogue_companies_list/company_source_76058_11.html
Are we seeing the results of faster ships and less sewage discharge?