380 Fertilizing the with Is this a viable way to help reduce dioxide levels in the ?

360 ive me half a tanker of iron, and I’ll give you an ice Twenty years on, Martin’s line is still viewed alternately age” may rank as the catchiest line ever uttered by a as a boast or a quip—an opportunity too good to pass up or a “biogeochemist.G The man responsible was the late John Martin, misguided remedy doomed to backfire. Yet over the same pe- former director of the Moss Landing Marine , who riod, unrelenting increases in carbon emissions and mount- discovered that sprinkling iron in the right ocean ing evidence of have taken the debate beyond could trigger blooms the size of a small city. In turn, academic circles and into the free market. the billions of cells produced might absorb enough heat-trap- Today, policymakers, investors, economists, environ- ping to cool the Earth’s warming atmosphere. mentalists, and lawyers are taking notice of the idea. A few Never mind that Martin companies are planning new, was only half serious when larger experiments. The ab- 340 he made the remark (in his Ocean sence of clear regulations for “best Dr. Strangelove accent,” either conducting experiments he later recalled) at an infor- An argument for: Faced with the huge at or trading the results mal seminar at Woods Hole consequences of climate change, iron’s in “” markets Oceanographic Institution outsized ability to put carbon into the complicates the picture. But (WHOI) in 1988. With global isn’t just an opportunity, it’s a responsibility. economists conclude that the warming already a looming growing urgency to solve our problem, others were inclined An argument against: It’s a meager, emissions problem will reward to take him seriously. temporary, unverifiable proposition involving anyone who can make iron private individuals dumping materials into At the time, ice-core re- fertilization work. 320 cords suggested that during the common waters of the world’s oceans. In past experiments “we past glacial periods, naturally A middle ground: Careful experiments were trying to answer the occurring iron fertilization conducted by scientists are our best hope question, ‘how does the world had repeatedly drawn as much work?’—not ‘how do we make (ppm)

for learning how much carbon can be 2 as 60 billion tons of carbon out sequestered without harming the ocean the world work for us?’ ” Ken- of the atmosphere. Laboratory ecosystem. neth Coale, the present-day experiments suggested that director of Moss Landing every ton of iron added to the Marine Lab, said recently. ocean could remove 30,000 to “They’re totally separate. We 110,000 tons of carbon from have not done the experiment 300 CO Atmospheric the air. Early climate models hinted that intentional iron fer- to address the issues that we’re talking about today.” tilization across the entire could erase 1 bil- “We’re in a learning process that involves a balance of lion to 2 billion tons of carbon emissions each year—10 to 25 science, commercial, and a whole variety of social activities percent of the world’s annual total. and interests,” said Anthony Michaels, director of the Wrig- Since 1993, 12 small-scale ocean experiments have shown ley Institute for Environmental Studies at the University of that iron additions do indeed draw carbon into the ocean— Southern California. “We’ve got to set up a measured process though perhaps less efficiently or permanently than first for moving forward.” thought. Scientists at the time agreed that disturbing the bot- The two scientists were speaking at a fall 2007 conference tom rung of the marine carried risks. that brought together some 80 participants representing the 280

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4 Oceanus Magazine Vol. 46, No. 1, 2008 www.whoi.edu/oceanus 380

THE —Carbon moves naturally through ground, ocean, and sky in a slow cycle over millions of years. People have short-circuited this cycle by quickly transferring hydrocarbons from ground to air. Iron fertilization proposes to accelerate the transfer of carbon from air back to ocean.

CO2 1 absorb CO2 from air to 2 Iron-rich dust is blown by winds grow, and 360 CO2 into the ocean and stimulates decompose blooms. to release CO2. Dust

3 Air and sea exchange CO2. 4 Phytoplankton 9 Rocks are take up CO2 to grow. 5 eventually eat phytoplankton But only a small percentage uplifted onto 7 and respire CO2. 340 of the sinking carbon reaches land and the . A tiny fraction is weathered to buried in sea oor sediments. release carbon Most is recycled back to the 6 Some carbon to soils and surface 100 to 1,000 years later sinks to the the atmosphere. by the ocean’s circulation. depths in the form of decaying biota and fecal pellets. 8 Over millions of years, carbon is incorporated into rocks or turned into hydrocarbons. 320 Jack Cook, WHOI

scientific, commercial, regulatory, and economic sides of the host of new, worrying consequences; and its effec- debate. The conference was convened by WHOI marine geo- tiveness is difficult for anyone to measure. (ppm) chemists Ken Buesseler and Scott Doney, and Hauke Kite- In certain regions, including the equato- 2 Powell of the WHOI Marine Policy Center. In talks and rial and north Pacific and the entire South- wide-ranging discussions, participants raised serious doubts ern Ocean, a simple iron addition does cause about the practicality, efficacy, and safety of large-scale iron phytoplankton to grow rapidly. But tiny fertilization. Yet many also seemed to accept that more sci- zooplankton, known as “grazers,” eat ence—in the form of carefully designed and conducted ex- much of the bloom almost as soon as it 300 CO Atmospheric periments—is the best way to resolve those doubts, one way starts. This begins a chain of recycling or the other. that ensues from the sea surface to the seafloor as grazers, , Not as simple as it sounds , , and microbes Martin made his pronouncement jokingly because he eat, excrete, and decom- knew that he was glossing over several hindrances to us- pose. Much of the im- Atmospheric carbon ing iron fertilization to sequester carbon in the ocean. Op- mense carbon prize dioxide levels have ponents to the idea are quick to point out the three major won by iron increased precipitously ones: It may be less efficient than it at first seems; it raises a addition since the 1850s, and continue to rise. 280

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Woods hole oceanographic institution 5 Ken Buesseler, WHOI IRON EXPERIMENTS OFF —Scientists aboard the Australian research vessel Aurora Australis studied the natural cycling of iron in the Southern Ocean in 2001. Ken Buesseler, a marine chemist at Woods Hole Oceanographic Institution, was aboard that expedition, and in 2002 he served as chief scientist of the Southern Ocean Iron Experiment (SOFeX). The three- operation investigated the results of adding iron to stimulate a phytoplankton bloom in the Southern Ocean. quickly leaks back into the atmosphere as building blocks needed for plankton growth. corals, or warm the surface layer and change carbon dioxide gas. “You might make some of the ocean circulation patterns. What is critical for the effectiveness of greener by iron enrichment, but you’re go- On the other hand, more plankton iron fertilization schemes is the amount ing to make a lot of the ocean bluer,” said might produce more of a chemical called of organic carbon that actually sinks from Robert Anderson, senior scholar at Lamont- dimethylsulfide, which can drift into the at- the surface and is sequestered in the depths Doherty Earth Observatory. mosphere and encourage cloud formation, (see Page 10). Only a small percentage of Other participants at the WHOI confer- thus cooling the atmosphere and helping to carbon—in the form of dead cells and fecal ence—John Cullen, a biological oceanog- counteract greenhouse warming. And oth- pellets—falls to the seafloor and stays there, rapher at Dalhousie University in Canada, ers argue that increased plankton supplies unused, for millennia. A higher percentage Andrew Watson, a biogeochemist at the might enhance fish stocks. (between 5 and 50 percent) will at least reach University of East Anglia, U.K., and Then there is the practical problem of middle-depth waters, where the carbon will Jorge Sarmiento, a modeler at Princeton’s verification. Iron fertilization companies remain for decades. Proponents consider this Geophysical Fluid Dynamics Laborato- would earn profits by measuring how much result good enough to buy society time to ry—pointed out several other ecological carbon they sequester and then selling the come up with other, more permanent solu- concerns. Large-scale iron fertilization, in equivalent to companies (or people) that ei- tions to greenhouse gas increases. altering the base of the food chain, might ther wish to or are required to offset their Beyond the inefficiency of carbon seques- lead to undesirable changes in fish stocks emissions. Any plan to sell sequestered car- tration, iron fertilization would likely cause and populations. Increased decom- bon requires a reliable accounting, and this other changes “downstream” of the ocean position of sinking could promises to be difficult in the ocean. patches where iron was added (see Page deprive deep waters of or produce So far, only three of 12 iron addition 14). The huge green phytoplankton blooms other greenhouse gases more potent than experiments have been able to show con- would take up not just iron but other nutri- carbon dioxide, such as nitrous oxide and clusively that any sequestration happened ents, too—, , and silica— methane. The plankton-choked surface wa- at all, according to Philip Boyd of the New essentially depleting nearby waters of the ters could block sunlight needed by deeper Zealand National Institute of and

6 Oceanus Magazine Vol. 46, No. 1, 2008 www.whoi.edu/oceanus Atmospheric Research. Perhaps more wor- rying to an investor, those sequestration numbers were low—about 1,000 tons of carbon per ton of iron added, as opposed to the 30,000 to 110,000 suggested by labora- tory experiments. • Anchorage Carefully designed research Despite the suspected drawbacks to full- scale iron fertilization, private companies— Copper River and many scientists—support the idea of Valley further experiments. Learning more about the ocean is in everyone’s interest, they ar- gue, and the larger experiments now being proposed are still far too small to wreak en- vironmental havoc. While the past experiments showed widely variable results, proponents read this as an opportunity for refinement through engineering. For millennia, humans have been repeating processes that at first were Gulf of Alaska marginally useful and tuning them to our purposes. Continued research could address a number of key questions (see box on Page 9), and those answers could point the way to higher yields and efficiency. Proponents of iron addition do acknowl- Jeff Schmaltz, MODIS Rapid Response Team, NASA Goddard Space Flight Center edge the possibility of environmental ill ef- IRON ADDITIONS, NATURAL AND EXPERIMENTAL—Top, a plume of dust from glacial sediments fects. Still, no such effects have been detected in Alaska blows far into the North Pacific Ocean. Storms like this, or from vast deserts such as during the past 12 experiments, probably be- the , are the natural way that iron gets into oceans to fertilize phytoplankton blooms. cause the experiments were small—around a Bottom, a bloom resulting from an intentional addition of iron in roughly the same region ton of iron added over a few hundred square (during the experimental Subarctic Ecosystem Response to Iron Enrichment Study in 2002) kilometers of ocean. By incrementally scaling shows up in the bottom center of the satellite image below as a red patch (indicating high levels up, they believe they can detect and avoid en- of from the microscopic marine plants). vironmental problems. • Anchorage As for the verification problem, both Copper River carbon markets and international ocean law are moving to accommodate so-called “” projects, such as iron fertil- ization, which capture and sequester car- bon from the air, according to Till Neeff of Kodiak Island EcoSecurities, a leading trader of carbon credits, based in London. By the time the science is worked out, he said, the econom- ics may be worked out as well. Anchoring all arguments for continued research is the brutal fact of global carbon Gulf of Alaska emissions. The most practical hope for deal- Queen Charlotte ing with emissions at the moment lies in a Islands piecemeal strategy of “stabilization wedges.” Fertilization Under this proposal, the world develops a experiment portfolio of emissions reductions and car- location bon-capture projects, each of which offsets one piece of the global emissions pie (see Page 23). Combined, these wedges must

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“The worst possible thing we “Let’s look at [iron 360 could do for climate change fertilization] in our technologies would be to invest portfolio for mitigation. in something that doesn’t work Uncertainty about and that has big impacts that the impacts shouldn’t

we don’t anticipate.” preclude careful research.” 340 —Lisa Speer, —Margaret Leinen,

Natural Resources Defense Council Kleindinst,Tom WHOI Climos

A wide range of stakeholders offered different perspectives on the ocean iron fertilization debate at a conference in September 2007 at Woods Hole Oceanographic Institution, including Lisa Speer, director of the Natural Resources Defense Council’s Oceans Program (left) and Margaret Leinen, chief science officer of Climos, a company exploring iron fertilization projects. 320 slow the growth of, and eventually lead to remain unknown. Further, no overarching worry for opponents of iron fertilization. Iron (ppm) 2 a net reduction in, our current global emis- international agency exists to enforce the fertilization companies might make superfi- sions of 7 billion to 8 billion tons of carbon treaty, so responsibility falls to individual cial estimates of the amount of carbon they per year. But with minimal progress so far nations, he said. Ship crews intending to sequester and enter a hefty balance in their on any wedges, and with China and flout an international treaty could do so by trading ledgers. Any large profits made from

300 CO Atmospheric set to increase emissions as they develop, electing to fly the flag of a country that has underregulated credits would encourage oth- iron fertilization beckons as one tool in a not signed it—a route that has already been er outfits to go into business. The collective toolbox of partial solutions. publicly considered by one company. impact to the world’s international waters “No option is without its impacts,” said Carbon trading markets are young but could be both disastrous and impossible to WHOI marine biochemist Ken Bues- growing, Neeff said. Strictly regulated mar- trace to any single liable party, Cullen said. seler, “whether we use wind turbines, grow kets, set in motion by the But those are future scenarios. By the biofuels, or use -saving fluorescent treaty, last year traded 430 million tons of time iron fertilization moves from experi- 280 bulbs, which contain .” carbon offsets (worth billions of dollars) ment to industry, laws may well be in place 1000 1200 among companies required to reduce1400 total Yearto regulate it, said Kite-1600Powell. Over the 1800 2007 But is it legal? emissions. (One ton of carbon equals 3.67 same period, increasing demand for carbon At present, iron fertilization falls into tons of carbon dioxide.) Regulatory markets offsets is likely to ensure that iron fertiliza- a gray area in both international law and don’t allow for iron fertilization at present, tion is profitable, he said, referring to a re- formal carbon-trading markets, but this is but this may change as more carbon sink cent economic analysis indicating a potential changing (see Page 22). projects gain approval. value of $100 billion over the next century. Iron fertilization Then there are vol- would happen on the “There are plenty of ways untary markets, Neeff Next steps: scientists and industry open ocean, which to do it wrong, but done said, in which con- Iron fertilization is being pulled in two is not owned by any cerned individuals or directions, as comments during a panel dis- country, according to right, [iron fertilization] does companies buy carbon cussion at the conference made clear. David Freestone, se- actually sequester carbon offsets to assuage their Iron fertilization is not a silver bullet, nior adviser in the Le- conscience or “green” said Margaret Leinen, the chief science of- gal Office of the World for hundreds of years in their image. Traders ficer at Climos, a firm exploring iron fer- Bank, who briefed the the place that it would would be free to sell tilization projects, and former assistant symposium partici- offsets from iron fer- director of geosciences at the U.S. National pants. While interna- ultimately end up anyway.” tilization in these mar- Science Foundation. But given the magni- tional treaties such as —Andrew Watson, Univ. of East Anglia kets. Voluntary markets tude of the greenhouse gas problem and the the London Conven- are growing rapidly, lack of progress so far, “let’s look at it in our tion, which governs Neeff said, but so far portfolio for mitigation,” she said. “Uncer- ocean dumping and pollution, might ad- they are equivalent to 7 million tons of car- tainty about the impacts shouldn’t preclude dress iron addition, treaty nations have not bon, worth about $100 million, per year— careful research.” yet decided whether it might constitute much smaller than regulatory markets. Lisa Speer of the Natural Resources De- pollution because its possible side effects Voluntary markets represent one more fense Council took a different view: “There

8 Oceanus Magazine Vol. 46, No. 1, 2008 www.whoi.edu/oceanus is a limited amount of money, of time, that mental audits of experiment plans. Russ hope to sell those carbon dioxide equiva- we have to deal with this problem,” she said. George, president of rival company Plank- lents as voluntary offsets. While scientific “The worst possible thing we could do for tos, who also attended the conference, research would focus on learning more climate change technologies would be to in- agreed in principle to the code. On Nov. 5, about how the ocean works, the companies vest in something that doesn’t work and that 2007, Planktos announced that it had dis- involved would be looking for ways to in- has big impacts that we don’t anticipate.” patched a ship equipped for an iron fertil- crease efficiency, make larger blooms in the Between these viewpoints a middle ization experiment but made no statements future, and monitor any negative effects. ground emerged: “There are plenty of ways about how it might comply with the code. As government-sponsored research on iron to do it wrong, but done right, [iron fer- What’s emerging for the next few years fertilization moves ahead in different coun- tilization] does actually sequester carbon is the prospect of a round of experiments tries, funding for larger experiments could for hundreds of years in the place that it involving around 100 tons of iron, which is develop into private and public partnerships. would ultimately end up anyway,” Watson 100 times larger than previously tried. Fi- Experiments on such a scale drive home said. That may be a tremendous advantage nanced by private companies, they could ei- one final point: that the near future of compared with more familiar but less se- ther be conducted by private interests with iron fertilization is probably modest on all cure approaches like planting trees, he said. limited sampling gear or by teams of sci- counts—size of experiments, likely prof- Skeptics should not dismiss the idea out of entists through grants. New, autonomous its, environmental side effects, and amount hand before scientists have had the chance technology promises to extend the duration of . However profit- to work out the details. of monitoring and improve measurements of able iron fertilization becomes, the dent it One way to quell doubts lies with care- how carbon sinks through the ocean. puts in atmospheric carbon levels in com- fully conducting larger experiments. But Yields from previous experiments cannot ing years will remain a small one. As these iron fertilization is unlikely to receive much be used to project whether larger-scale fer- ocean scientists work to assemble their sta- 380 more U.S. federal funding. It falls to en- tilizations would send millions, thousands, bilization wedge to mitigate carbon dioxide trepreneurs concerned about the climate or fewer tons of carbon into the oceans’ emissions, they remind the rest of the world problem to fund the work, and they need middle depths, Buesseler said. Still, com- that many more wedges must be found. scientists’ participation to make sure the mercial groups sponsoring new experiments —Hugh Powell right questions are asked and answered. In a parallel with the way universi- ties routinely conduct trials of the safety 360 and efficacy of potential pharmaceuticals, Unresolved Questions Michaels pointed out that oceanographers Twelve small experiments have shown that blooms of phytoplankton may need to learn how to be involved with consistently result from intentional addition of iron to the ocean. But the tests of iron fertilization. “We have to evolve efficacy and ecological impacts of iron fertilization remain uncertain, a set of skills within our community to have particularly with larger-scale experiments. If and when a new round of those kinds of roles,” he said. “Who else experiments is begun, these questions will be first on the list: should be figuring that out but us?” 340 Though many scientists are keen on the • How long will carbon be sequestered in the ocean? idea of future research, fewer are willing to • How deep is deep enough to accomplish this? team up with a private company to do it, for fear of a real or perceived effect on the im- • How can sequestration efficiency be increased? partiality of their research. Still, research- • How does the ocean change during and after a bloom? ers may need to convince themselves that just because the idea is potentially profitable • Which phytoplankton and grazers raise sequestration efficiency? 320 doesn’t mean it’s wrong—or simply accept that further research is going to happen. • Which parts of the ocean are best for iron fertilization? (ppm) “Commercial efforts are moving forward • What size and what shaped patch should be fertilized? 2 with or without scientific input,” Buesseler said. “We need to be able to evaluate their • How often and how continually should iron be added? impacts and changes to the ocean carbon • What kinds of currents and surface conditions give the best results? cycle, based upon the best possible oceano- 300 CO Atmospheric graphic methods.” • How can the amount and fate of carbon from a bloom be verified? For their part, private companies hope to • How can effects downstream of experiments be detected? collaborate with researchers. Of the hand- ful already in business, one—Climos—re- • How can the production of other greenhouse gases be monitored? cently proposed a code of ethics supporting involvement by scientists and full environ- 280

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