Dan-- I'm not sure I'd agree that this was decent data.
A few people have asked me about this... I'll paste my response below: The big problem I have w/ the paper is that clearly carbon does make it to the deep ocean. Many other recent studies (VERTIGO, EIFEX, Kerguelen plateau) show that during bloom conditions, efficiency of export (either bypassing zooplankton, or with the addition of their fecal pellets) is substantially greater and in the higher latitudes we see in the neighborhood of 50% sequestration to deep water (> 500m). Furthermore there are numerous paleo studies showing that during highly productive times deep sea sediments are thicker-- i.e. biomass made it there--as well as showing a correlation between atmospheric CO2 and productivity (and iron). We know that many modeling studies show that iron addition over a hundred years might result in significant atmospheric drawdown (~50ppm). We have timelapse pictures from the seafloor (Porcupine seabight in No Atlantic, and many others) showing thick green biomass laying like a carpet at the bottom after a bloom and subsequently decomposing over time. So zooplankton dynamics clearly *do* allow for deep carbon sequestration in many places, and at many times. (Otherwise we would not see the oxygen demand at depth that we do from decomposition--in addition to the carbon concentration itself). Basically, this was not a designed experiment. It was an afterthought as a the result of the serendipity of these machines continuing to transmit data as they drifted aimlessly across the pacific for two years after their initial use. So, many of the things that you would want to see were not available-- - there was no continuous calibration of the correlation between the optical characteristics of the particles observed versus the actual carbon inside of them (for instance diatoms have substantially different amounts of carbon / volume and weight than other taxa because their bodies have more silica, also different zooplankton will excrete fecal pellets w/ different composition). other teams that have used optics as a proxy for carbon have undertaken painstaking daily measurements of the particles at different depths in the water column and their carbon composition vs size/weight to produce a linear regression of this correspondence. this relationship would change substantially over time and for different taxa, and we know that different taxa frequently rotate in their predominance as nutrient conditions change, etc. - there was no corroboration of ocean color data w/ the carbon profilers, we don't know whether they were in blooms or not. - there was no satellite altimetry-- we don't know whether these profilers stayed inside moving eddies or were spun out from one to the next. what are we really looking at? - there was no acknowledgment that the movement of the profilers vs the water column and associated productivity over the course of a 2-3 week bloom meant that the surface carbon data did not necessarily correspond to the subsequent carbon export-- and yet the data as presented in graph form suggests that this is a foregone conclusion. proposed future OIF studies would be on the scale of 100-200km in diameter precisely because you need to know that the instrument is under the intended area for the duration of the observation. - there was no nutrient condition data available for the water column as the profilers moved... was there sufficient nitrate/phosphate, iron? this high silicate water for instance? could diatoms have grown there? etc ... Bishop's take-away from what I can read in the press release and other comments seems to be that this data revises our understanding of the biological pump / carbon cycle substantially--though what exactly he is saying is not clear. His quotes argue that zooplankton dynamics are under emphasized, and this is a "complicated" process-- i.e. simple iron addition is not a magic bullet (though iron addition is really secondary to the primary point). I'm not sure who he's speaking to-- obviously most of those proposing further studies understand this. The Science Policy forum from last year articulated the significant uptick in sophistication of what future studies must include in order to make meaningful progress on OIF as a technique. I don't think these results by contrast get us very far (if at all) in that direction. I think it's important to say that the paper by itself seems a reasonable reflection of the data as collected. This may be (yet) another example of the press release somewhat confusing the conclusion of what was actually published. Dan On May 7, 2:16 pm, dsw_s <[email protected]> wrote: > It's good to hear that there's some decent data, even if it isn't > particularly encouraging for OIF. > > On May 7, 2:52 pm, DW <[email protected]> wrote: > > >http://www.greentechmedia.com/articles/read/report-iron-fed-plankton-... > > Report: Iron-Fed Plankton Slow to Remove CO2 > > > Two Berkeley Lab researchers have analyzed data from sea-diving > > devices and found that seeding iron to boost plankton growth doesn’t > > lead to the quick scrubbing of carbon dioxide from the atmosphere. > > > Can spreading iron in oceans reduce a lot of carbon dioxide in the > > atmosphere? Not as much or quickly as you'd think, said researchers at > > the Lawrence Berkeley National Laboratory. > > > After analyzing data from ocean-diving devices that trawled for carbon > > dioxide in the deep sea for over a year, Jim Bishop and Todd Wood > > concluded that phytoplankton aren't the carbon-dioxide removal > > machines that some believe them to be. > > > "Just adding iron to the ocean hasn't been demonstrated as a good plan > > for storing atmospheric carbon," says Bishop, who also is an earth > > sciences professor at UC Berkeley, in a statement. "What counts is the > > carbon that reaches the deep sea, and a lot of the carbon tied up in > > plankton blooms appears not to sink very fast or very far." > > > An upcoming issue of the journal Global Biogeochemical Cycles will > > publish the researchers' results, the lab said Wednesday. > > > There has been a long-held theory, called Iron Hypothesis, that > > stimulating plankton blooms could significantly remove carbon dioxide, > > a key greenhouse gas that contributes to global warming, from the > > atmosphere and deposit them in the ocean. Like plants on land, > > plankton would eat up carbon dioxide as part of its energy production > > process under the sun. There are two ways for carbon to sink and get > > buried in the deep sea. One is through the waste created by sea > > creatures that eat plankton. And the other is through the death of the > > plankton themselves. > > > The earth's eco-system has its own, natural ways of producing and > > removing carbon dioxide from the atmosphere. But the system lacks the > > power to absorb the growing amount of carbon dioxide and other > > greenhouse gases produced by human activities such as generating > > electricity and driving cars. > > > Iron proved to be the steroid that could boost plankton growth, > > according to research by John Martin at the Moss Landing Marine > > Laboratories. Martin then proposed that seeding iron in the ocean > > could turn plankton into weapons for fighting global climate change. > > > Companies have emerged to try to make money from this carbon- > > sequestration idea. One of them, Planktos, gave up on the idea last > > year (see Planktos Seeks New Business Ideas). Climos, based in San > > Francisco, is still in business. CEO Dan Whaley said the Berkeley Lab > > researchers’ paper didn’t provide the necessary details, such as what > > types of plankton were observed, to show that phytoplankton aren’t > > good at burying carbon dioxide in the ocean. > > > “I have the utmost respect for Jim Bishop. But this is clearly not an > > iron experiment,” Whaley said. “He seems to suggest that growing more > > plankton won’t store much more carbon – but I think that the > > geological record argues that it has.” > > > Bishop and Wood said their research showed that the notion of global > > warming being halted or even reversed by boosting plankton growth is > > not as easily achieved as some have claimed. > > > The researchers based their findings on data provided by devices > > called Carbon Explorers, which were first launched in 2002 as part of > > project by the Moss Landing Marine Lab and the Monterey Bay Aquarium > > Research Institute. The project set out to test Iron Hypothesis in the > > ocean between New Zealand and Antarctica during the summer. > > > The Carbon Explorers not only collected data during the iron-seeding > > experiments, they also did so in the fall and winter for over a year, > > after evidence of the iron scattering had disappeared, the lab said. > > The devices were lowered into a depth of 800 meters and more. > > > Results from initial studies showed that, indeed, an artificially > > induced plankton bloom could remove 10 percent to 20 percent of the > > carbon from the ocean surface and deposit them to below 100 meters. > > The research team published a paper in the journal Science in April > > 2004. > > > Those results were based on data collected 60 days after the iron > > seeding. But data from the Carbon Explorers in the subsequent 16 > > months demonstrated that how much carbon can be sequestered by > > plankton blooms depended largely on the feeding and lifecycle of the > > zooplankton that eat phytoplankton. > > > Zooplankton don't get easy access to phytoplankton throughout the > > year, however, because of seasonable weather patterns and how they've > > adopted to surviving in darkness when sun doesn't shine in Antarctica > > during winter. As a result, the amount of carbon that can be absorbed > > by plankton isn't as great as anticipated, the Berkeley Lab > > researchers said. > > > -- > > > On May 6, 2:17 pm, DW <[email protected]> wrote: > > > >http://www.sciencedaily.com/releases/2009/05/090506131512.htm > > > Science News > > > Ocean Carbon: Dent In Iron Fertilization Hypothesis Previously > > > Proposed To Address Climate Change > > > > ScienceDaily (May 6, 2009) — Oceanographers Jim Bishop and Todd Wood > > > of the U.S. Department of Energy’s Lawrence Berkeley National > > > Laboratory have measured the fate of carbon particles originating in > > > plankton blooms in the Southern Ocean, using data that deep-diving > > > Carbon Explorer floats collected around the clock for well over a > > > year. Their study reveals that most of the carbon from lush plankton > > > blooms never reaches the deep ocean. > > > > The surprising discovery deals a blow to the simplest version of the > > > Iron Hypothesis, whose adherents believe global warming can be slowed > > > or even reversed by fertilizing plankton with iron in regions that are > > > iron-poor but rich in other nutrients like nitrogen, silicon, and > > > phosphorus. The Southern Ocean is one of the most important such > > > regions. > > > > “Just adding iron to the ocean hasn’t been demonstrated as a good plan > > > for storing atmospheric carbon,” says Bishop, a member of Berkeley > > > Lab’s Earth Sciences Division and a professor of Earth and planetary > > > sciences at the University of California at Berkeley. “What counts is > > > the carbon that reaches the deep sea, and a lot of the carbon tied up > > > in plankton blooms appears not to sink very fast or very far.” > > > > The reasons, while complex, are most likely due to the seasonal > > > feeding behavior of planktonic animal life, and specifically to the > > > effects of the dark Antarctic winter on plant and animal growth and > > > the mixing of surface and deep waters by winter storms. Phytoplankton > > > blooms in the spring may indicate that much of the zooplankton > > > (animal) population essential for carbon sedimentation has starved > > > during the winter. > > > > The Carbon Explorers involved in the study were launched in January, > > > 2002, as part of the Southern Ocean Iron Experiment (SOFeX), a > > > collaboration led by scientists from Moss Landing Marine Laboratory > > > and the Monterey Bay Aquarium Research Institute. SOFeX was meant to > > > test the Iron Hypothesis in waters between New Zealand and Antarctica > > > during the Antarctic summer. The Berkeley Lab Carbon Explorers were > > > originally intended to monitor the iron-fertilization experiment for > > > 60 days, but they continued to report by satellite throughout the > > > Antarctic fall and winter and on into the following year. > > > > “We would never have made these surprising observations if the > > > autonomous Carbon Explorer floats hadn’t been recording data 24 hours > > > a day, seven days a week, at depths down to 800 meters or more, for > > > over a year after the experiment’s original iron signature had > > > disappeared,” Bishop says. > > > > He explains that “assumptions about the biological pump – the way > > > ocean life circulates carbon – are mostly based on averaging > > > measurements that have been made from ships, at intervals widely > > > separated in time. Cost, not to mention the environment, would have > > > made continuous ship-based observations impossible in this case. > > > Luckily one Carbon Explorer float costs only about as much as a single > > > day of ship time.” > > > > The Iron Hypothesis, science and speculation > > > > In the 1980s, oceanographer John Martin of the Moss Landing Marine > > > Laboratories, who died in 1993, proposed that iron added to regions of > > > the ocean that are otherwise rich in nutrients but poor in iron (so- > > > called high-nutrient, low-chlorophyl, or HNLC, regions) can stimulate > > > the growth of phytoplankton – a bold scientific hypothesis that has > > > since been proven correct. > > > > Martin went further, however, when he suggested that artificial iron > > > fertilization of the oceans could change the climate. “Give me half a > > > tankerful of iron and I’ll give you an Ice Age,” he boasted in 1988. > > > > In testing the Iron Hypothesis, SOFeX’s investigators acknowledged > > > that matters were not quite that simple, and that the crucial question > > > was not whether plankton blooms could be induced but whether the > > > carbon they captured was removed to the deep sea. > > > > The SOFeX research vessels fertilized and measured two regions of > > > ocean, one in an HNLC region at latitude 55 degrees south and another > > > at 66 degrees south. Carbon Explorers were launched at both these > > > sites; a third Carbon Explorer was launched well outside the iron- > > > fertilized region at 55°S as a control. Berkeley Lab scientists Todd > > > Wood, > > ... > > read more » --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en -~----------~----~----~----~------~----~------~--~---
