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CITATION Sabine, C.L., H. Ducklow, and M. Hood. 2010. International carbon coordination: Roger Revelle’s legacy in the Intergovernmental Oceanographic Commission. Oceanography 23(3):48–61, doi:10.5670/oceanog.2010.23.

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do wnLOADED from www.tos.org/oceanography Celebrating 50 Years of the Intergovernmental Oceanographic Commission

In ternational Carbon Coordination

Roger Revelle’s Legacy in the Intergovernmental Oceanographic Commission

By Christopher L. Sabine, Hugh Ducklow, and Maria Hood

R oger Revelle in his lab circa 1958. Photo courtesy of Scripps Institution of Oceanography Archives, UC San Diego Libraries

48 Oceanography Vol.23, No.3 ABSTRACT. Since its inception in 1960, the Intergovernmental Oceanographic INTRODUCTION Commission (IOC) has been responsible for organizing and coordinating the Recognizing that global issues scientific investigation of ocean carbon. Roger Revelle (Scripps Institution like climate change could only be of Oceanography) first articulated the principal need for international and addressed through international intergovernmental coordination to address global-scale problems such as climate and intergovernmental cooperation, change when IOC was first developed. Regional to global-scale carbon studies the Intergovernmental Conference started in earnest with the International Decade of Ocean Exploration (IDOE) and on Oceanographic Research (also Geochemical Ocean Sections Study (GEOSECS) programs in the 1970s, but they were referred to as the “First Oceanographic hampered by technological barriers that limited both the precision of carbon system Conference”) met in Copenhagen in measurements and the greater sampling frequency needed for a comprehensive global 1960 to create the Intergovernmental view. In 1979, IOC established the Committee on Climate Change and the Ocean Oceanographic Commission (IOC). (CCCO) with Revelle as Chair. CCCO called for a carbon observation program From the beginning, the need to and sampling strategy that could determine the global oceanic CO2 inventory to an understand ocean carbon was seen accuracy of 10–20 petagrams of carbon (Pg C). Perfection of the coulometric analysis as a major IOC driving force. During technique of total dissolved inorganic carbon (DIC) in seawater by Ken Johnson a Paris preparatory meeting for the (University of Rhode Island) and introduction of certified reference materials for Copenhagen conference in March 1960, DIC and alkalinity by Andrew Dickson (Scripps Institution of Oceanography) made Roger Revelle, then director of Scripps such a study possible. The first global survey of ocean 2CO was carried out under the Institution of Oceanography, summa- joint sponsorship of IOC and the Scientific Committee on Oceanic Research (SCOR) rized the purposes of this new United in the Joint Global Ocean Flux Study (JGOFS) and the World Ocean Circulation Nations organization, citing the need

Experiment (WOCE) in the 1990s. With these programs and underway pCO2 for a better understanding of ocean measuring systems on research vessels and ships of opportunity, ocean carbon data carbon (Revelle, 1960): grew exponentially, reaching about a million total measurements by 2002 when Taro Takahashi (Lamont-Doherty Earth Observatory) and others provided the first robust In general, oceanographic research, like mapping of surface ocean CO2. Using a new approach developed by Nicolas Gruber many other kinds of research, is best (ETH Zürich) and colleagues with JGOFS-WOCE and other synthesized data sets, done by individuals or small groups one of this article’s authors (Sabine) with a host of coauthors estimated that the total working independently. However, accumulation of anthropogenic CO2 between 1800 and 1994 was 118 ± 19 Pg C, just there are some research problems that within the uncertainty goals set by JGOFS and IOC prior to the global survey. Today, require international co-operation… ocean carbon activities are coordinated through the International Ocean Carbon Scientific problems that require nearly Coordination Project (IOCCP). Ocean carbon measurements now accumulate at a simultaneous observations over a rate of over a million measurements per year—matching the total number achieved wide area or over the entire ocean also over the first three decades of ocean carbon studies. IOCCP is actively working to demand international co-operation combine these data into uniform data sets that the community can use to better in taking the observations, and close understand ocean carbon uptake and storage. The problem of ocean acidification co-ordination to ensure comparability caused by uptake of anthropogenic CO2 is now a major target of IOC and IOCCP. of results. An example is the present

Oceanography September 2010 49 attempt to determine the total carbon and more countries participate in endorsed the US effort by initiating the dioxide content in the atmosphere and large-scale field programs, the need for Long-term and Expanded Programme the change in this content with time this type of coordination will become of Ocean Exploration and Research as a result of the input from fossil fuel increasingly important. Through (LEPOR), which highlighted the study combustion and the loss to the ocean activities such as the International Ocean of air-sea gas exchange and the effects and biosphere. One of the questions Carbon Coordination Project, IOC is of turbulence and breaking waves on we are asking is: Where is the carbon dioxide absorbed by the ocean? Does it remain in the surface layers or does it extend throughout the ocean volume? Roger Revelle was the first to recognize that understanding the gigantic geochemical At the time of this statement, it was experiment being conducted by adding assumed, based on fundamental thermo- dynamics, that the ocean was absorbing “fossil fuel CO2 to the ocean required an CO2 from the atmosphere, but it was international effort of unprecedented scale, unclear how much was absorbed and complexity, and integration. how quickly it mixed throughout the ocean volume. There were relatively few high-quality inorganic carbon measurements in the ocean and no good tech- realizing the vision of coordination and the exchange of elements such as halo- niques for isolating the anthropogenic cooperation envisioned by Revelle and carbons and carbon dioxide (UNESCO,” component. The role of ocean biology the First Oceanographic Conference 1975). This new program also promoted in controlling carbon distributions in 50 years ago. the need for baseline geochemical the ocean was also poorly understood surveys, including carbon dioxide, and from local to global scales. Revelle recog- LONG-TERM AND EXPANDED studies of how climate variability impacts nized the need for countries to work PROGRAMME OF OCEAN ocean biology. together to address these compelling EXPLORATION AND RESEARCH The first high-quality, fully docu- global-scale questions. IOC concentrated its early efforts in mented global inorganic ocean carbon Since its inception, IOC has been the 1960s on the International Indian measurements were carried out as part of providing international coordination Ocean Expedition, but there was little the Geochemical Ocean Sections Study for ocean carbon and biogeochemical focus on ocean carbon, except for (GEOSECS) between 1971 and 1978. measurements, with its programs primary production measurements, The GEOSECS program made roughly evolving to meet new challenges as the until the 1970s when the United States 6,000 measurements of dissolved inor- science progressed and coordination initiated the International Decade ganic carbon (DIC) and total alkalinity needs changed. As techniques develop of Ocean Exploration (IDOE). IOC (TA) in the Atlantic, Pacific, and Indian oceans as well as the Mediterranean and Christopher L. Sabine ([email protected]) is a supervisory oceanographer at the Red seas (Figure 1). National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Shortly after completion of the Laboratory, Seattle, WA, USA, and chair since 2002 of the Intergovernmental GEOSECS cruises, two publications Oceanographic Commission-Scientific Committee on Oceanic Research (IOC-SCOR) independently proposed the first International Ocean Carbon Coordination Project. Hugh Ducklow is Director, The techniques for estimating anthropo-

Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, USA. Maria Hood genic CO2 concentrations from ocean is an IOC consultant and former project coordinator for the CO2 Advisory Panel and the carbon measurements (Brewer, 1978; International Ocean Carbon Coordination Project, UNESCO, Paris, France. Chen and Millero, 1979). However,

50 Oceanography Vol.23, No.3 these approaches were criticized in the of sustained global ocean observations. This figure was at least twice as good literature (e.g., Shiller, 1981; Broecker Initially, these programs focused their as the best estimates at the time and et al., 1985) and never found general efforts on physical oceanographic obser- would require a significant improve- acceptance in the community. Not only vations. To complement these programs, ment in both measurement accuracy were there concerns about the calcula- the Scientific Committee on Oceanic and data coverage relative to GEOSECS. tion techniques, but there were also Research (SCOR) teamed up with IOC to The belief that this accuracy could be concerns about the magnitude of the create the Committee on Climate Change achieved was based on the development anthropogenic signal relative to the large and the Ocean (CCCO), which included work of Johnson et al. (1985) to perfect natural background of inorganic carbon a strong biogeochemical component. the coulometric analysis of DIC, which in the ocean. The estimated accuracy provided a significant improvement of the GEOSECS measurements was CCCO CO2 ADVISORY PANEL in accuracy relative to the titrametric ~ ± 20 µmol kg–1 (e.g., Takahashi et al., Given the importance of understanding procedures used during GEOSECS. 1982). Although these measurements the connections between the ocean and In the early and mid 1980s, the were state of the art at the time, Broecker climate change, Roger Revelle agreed US scientific community started devel- et al. (1979) commented in an article in to chair CCCO when it was created in oping a strategy for large-scale, coordi- Science that “…unless [inorganic carbon] September 1979. As noted previously, nated biogeochemical process studies measurements that are more accurate there was concern that ocean CO2 under the title Global Ocean Flux Study by an order of magnitude can be made, uptake estimates could not be properly (GOFS). By 1987, several countries were at least a decade will pass before direct constrained with the limited quality planning similar carbon cycle and flux confirmation of the model-based and number of observations available studies, so SCOR and the International

[anthropogenic CO2 uptake] estimates (Broecker et al., 1979; Brewer, 1986). In Council of Scientific Unions (ICSU) will be obtained.” These words turned 1984, CCCO established a CO2 Advisory gathered the leading experts in the ocean out to be prophetic, as it was more than Panel, chaired by Revelle, which recom- carbon cycle for a meeting in Paris to a decade before another global carbon mended the development of a carbon agree on the goals, scientific elements, survey was attempted and nearly two observation program and sampling topics of emphasis, and organizational decades before an improved technique strategy that could determine the global structure for an internationally coordi- for estimating anthropogenic CO2 from oceanic CO2 inventory to an accuracy nated study known as the Joint Global DIC measurements was published. of 10–20 petagrams of carbon (Pg C). Ocean Flux Study (SCOR, 1987). Another notable achievement at the end of the 1970s was the development of the IOC/World Meteorological Organization (WMO)-Integrated Global Ocean Services System (IGOSS), which collected and exchanged data to produce ocean-related products and services. This program is the forerunner of today’s IOC-WMO Joint Technical Commission on Oceanography and Marine Meteorology (JCOMM). The World Climate Programme was also developing the first Pilot Ocean Monitoring Study (POMS) as a precursor of a Global Ocean Observing System Figure 1. Map of station locations for the Geochemical Ocean Sections (GOOS), and was promoting the idea (GEOSECS) program (1972–1978).

Oceanography September 2010 51 Meeting participants recognized that planning and commitments for imple- Components of this chapter included the understanding the carbon cycle would be menting the carbon observations. global CO2 survey in conjunction with central to JGOFS and that global oceanic Although the carbon work had a WOCE, long time-series observations,

CO2 measurements would be critical to purely research focus, CCCO was also and seasonal surveys of CO2 partial pres- that understanding. JGOFS was devel- promoting the establishment of a more sure (pCO2) in the surface ocean. The oped under SCOR leadership in 1987, operational sustained ocean observing promotion of time series observations and the program was later accepted system. Based on recommendations grew out of recognition that an under- by the newly created International from the Technical Committee for standing of variability over a range of Geosphere-Biosphere Program (IGBP) Ocean Processes and Climate and time scales from seasonal to interannual in 1989 as its first ocean project, setting the WMO Executive Council, the was required to better understand the a precedent for wide support of interna- 15th IOC Assembly in July 1989 called connection between climate and ocean tional collaboration in the ocean sciences for the design and implementation of biogeochemistry. Although a very few (JGOFS, 1990). a global operational observing system. time series sites, such as the Canadian At the same time, the international Consequently, CCCO created an Station P time series in the North physical oceanographic community was Ocean Observing System Development Pacific and the Icelandic time series also organizing itself for a global study Panel (OOSDP) to specify the require- in the Irminger and Iceland seas, were of ocean circulation called the World ments for ocean measurements in already making regular ocean observa- Ocean Circulation Experiment (WOCE). support of climate observations. The tions, several large multidisciplinary The intersection of the WOCE and first “official” use of the phrase Global time series sites were started around JGOFS programs provided an opportu- Ocean Observing System (GOOS) 1990. At that time, the United States nity for a comprehensive global survey to refer to this new system occurred had just started monthly shipboard of ocean carbon distributions that could during the 23rd IOC Executive Council time series sampling off Hawaii and accomplish the CO2 inventory goal set meeting in March 1990. Later that year, Bermuda, including high-quality DIC by the CCCO CO2 Advisory Panel and endorsement of the GOOS concept analyses, sediment traps, and primary endorsed by JGOFS. After some nego- widened further as the newly formed productivity measurements (Karl and tiating, WOCE agreed to accommodate Intergovernmental Panel for Climate Michaels, 1996). Other sites, including a small CO2 contingent on the ships Change (IPCC) and the Second World KERFIX (Kerguelen Fixed station) taking part in the WOCE Hydrographic Climate Conference both endorsed in the Southern Ocean, DYFAMED Programme one-time global hydro- GOOS as a major component of the (DYnamique des Flux Atmosphériques graphic survey. proposed Global Climate Observing en MEDiterranée) in the Mediterranean System (GCOS). Sea, ESTOC (European Station for Time JGOFS-CCCO Advisory The original US GOFS Program Series in the Ocean) near the Canary

Panel on Ocean CO2 was conceived as “sediment traps and Islands, and CARIACO (CArbon

Since the objectives of the SCOR-JGOFS CO2 measurements” (GOFS, 1984). In Retention In A Colored Ocean) off and IOC-CCCO groups were congruent 1990, the international JGOFS program Venezuela, were started as part of the with respect to CO2, it was agreed published a science plan that adopted international WOCE/JGOFS effort. that JGOFS and CCCO should jointly an expanded ecological-biogeochemical The seasonal pCO2 surveys were assume responsibility for executing a focus, with a wide array of ecological prompted by the Tans et al. (1990) global ocean CO2 observation program. measurements to undergird models publication that combined 30 years

Accordingly, in September 1988 the relating ocean ecology (e.g., nitrogen worth of shipboard pCO2 observations CCCO panel was disbanded and the cycling and new production) to the in an attempt to develop the first global

Joint JGOFS-CCCO Advisory Panel on carbon cycle (JGOFS, 1990). One estimates of air-sea CO2 fluxes and

Ocean CO2 was created to provide the chapter of the 1990 science plan was examine the global carbon budget. This primary focal point for international devoted to large time/space surveys. initial work suggested that the ocean

52 Oceanography Vol.23, No.3 sink for CO2 was only about half of the the first year, but by 1992 production had of macronutrients (e.g., nitrogen, phos- magnitude inferred from models (e.g., stabilized and these CRMs were routinely phorus) but relatively little productivity the first-generation, three-dimensional being distributed to all of the US groups as evidenced by low chlorophyll concen- ocean carbon model of Maier-Reimer participating in the JGOFS/WOCE trations. From an ocean carbon stand- and Hasselman [1987] or the ocean box program as well as carbon chemists from point, these high nutrient, low chloro- model that used GEOSECS data by Bolin several other countries. In 1994, CRMs phyll (HNLC) regions were also seen et al. [1983]). However, most of the high- were also certified for total alkalinity. as a potential way of explaining the low latitude ocean was excluded because of The CO2 Advisory Panel facilitated the ice age atmospheric CO2 concentrations lack of data. This work highlighted the standardization of analyses by helping observed by Barnola et al. (1987) based need for a substantially increased surface to organize instrument comparison on ice core data (i.e., increased iron dust observation program. exercises and establishing internationally stimulating ocean uptake of CO2 during agreed standard protocols. For example, glacial periods) and as an opportunity JGOFS-IOC Advisory a methods comparison exercise for DIC for humans to increase modern ocean

Panel on Ocean CO2 and total alkalinity organized by the CO2 carbon uptake by fertilizing these HNLC Through the JGOFS program, the Advisory Panel clearly demonstrated the regions with iron. John Martin (Moss number of biogeochemical observations need for consistent methods and CRMs Landing Marine Laboratories) is often began to increase dramatically in the (Poisson et al., 1990a,b). By January quoted as having said at a seminar in 1990s as did the need for coordination 1994, the panel had helped produce the Woods Hole, Massachusetts, “Give me among groups and nations. A decision to protocols for JGOFS core measurements a half tanker of iron, and I will give you phase out CCCO in December 1992 was (JGOFS, 1994) and the CO2 Methods an ice age.” Martin’s pioneering work followed by an agreement to continue Handbook (DOE, 1994). on iron fertilization led to many in situ the CO2 Panel directly under IOC with joint sponsorship by JGOFS so the group could continue to facilitate international coordination and maintain active links to The creation of IOC in 1960 provided the ocean biogeochemistry community. the platform to launch this effort, which Some of the primary issues taken grew eventually to encompass over a on by the CO Panel were the need for 2 million ocean carbon system measurements standard analysis protocols and the utility “ of developing certified reference mate- annually, and laid the groundwork for a rials (CRMs) for the inorganic carbon global ocean observing system. measurements. Andrew Dickson (Scripps Institution of Oceanography) developed a technique for collecting and sterilizing large batches of seawater that were then Another important development mesoscale iron fertilization process bottled so they could be distributed during the 1990s was introduction of the studies (see De Baar et al., 2005, ”and to ocean carbon chemists to provide a iron hypothesis—that primary produc- references therein) and investigations secondary check on their instrument tivity in some regions of the ocean is into the feasibility of purposeful ocean calibrations (see Dickson, 2010, in this limited by the availability of certain carbon sequestration. IOC, in collabo- issue). His first batch was bottled in micronutrients (Martin et al., 1994). ration with other UN organizations, January 1990 and was certified for DIC A lack of available iron, an essential addressed the issue of using the ocean using coulometric and manometric micronutrient for primary production, to sequester excess atmospheric CO2 analysis techniques. There were difficul- helped explain why there were large with a comprehensive report high- ties with some unstable batches during ocean regions with high concentrations lighting the potential environmental

Oceanography September 2010 53 consequences and international legal system, including data management and during the last decade of the century questions surrounding this proposal synthesis activities, and on providing (Figure 3B). Given the spatial and

(GESAMP, 1997). scientific and technical advice on ocean temporal variability of surface pCO2, The field portions of the WOCE and carbon sequestration. This new panel however, there were not enough global JGOFS programs ran for about a decade. met for the first time in September 2000 observations to develop robust surface

In total, nearly 100 WOCE Hydrographic under the chairmanship of Douglas pCO2 maps until the late 1990s.

Programme cruises were run with CO2 Wallace (Leibniz Institute of Marine In 1997, Taro Takahashi (Lamont chemists aboard (Figure 2). Carbon Sciences at the Christian-Albrechts Doherty Earth Observatory) compiled measurements were a standard compo- Universität zu Kiel) and laid the founda- 30 years worth of surface ocean CO2 nent of all JGOFS cruises. Iron fertiliza- tions for the GOOS background report observations (~ 250,000 measure- tion studies were conducted in a variety on establishing a global ocean carbon ments) to produce the first monthly of HNLC regions. Underway surface observation system (UNESCO, 2002). global surface pCO2 maps (Takahashi pCO2 measurements became more This report outlined ongoing ocean et al., 1997). Although the number frequently collected on research cruises carbon observations as well as the many of research cruises dropped dramati- and the JGOFS time-series sites were technical challenges that would need cally at the end of the WOCE/JGOFS clearly showing variability over a range to be overcome to establish a system of program (Figure 4), the number of of time scales (e.g., Winn et al., 1994; ocean carbon measurements that could surface CO2 observations continued to Bates, 2002). meet scientific goals. One of the biggest increase (Figure 3). Part of the reason challenges to be tackled was how to for this change was the placement of

IOC-SCOR Ocean CO2 appropriately and adequately measure underway CO2 systems on research

Advisory Panel the highly variable surface pCO2. vessels and commercial ships of oppor-

With the completion of the JGOFS field The number of surface CO2 observa- tunity (SOOP). The IOC-SCOR Ocean components in the late 1990s and the tions grew exponentially through the CO2 Advisory Panel was able to help emergence of GOOS, the CO2 Advisory 1960s, 1970s, and 1980s (Figure 3A), facilitate the growth of SOOP carbon

Panel was restructured as the joint but with JGOFS, WOCE, and the strong observations by promoting pCO2 system

IOC-SCOR Ocean CO2 Advisory Panel focus on ocean carbon research in the comparison exercises (e.g., Koertzinger with a focus on developing recommen- 1990s, many more ships were instru- et al., 2000) and through its IOC connec- dations for an ocean carbon observing mented with underway pCO2 systems tion to the developing GOOS, which was also instrumenting commercial ships with physical oceanographic equip- ment. By the time Takahashi updated his climatology in 2002, the surface

pCO2 database had grown from approximately 250,000 measurements to more than 940,000 (Takahashi et al., 2002). Approximately three million measurements were included in his latest update (Takahashi et al., 2009). In the years following the WOCE/ JGOFS field programs, the number of ocean interior carbon observations dropped precipitously because

Figure 2. Map of station locations for the World Ocean Circulation Experiment/ the programs moved to synthesis and Joint Global Ocean Flux Study (WOCE/JGOFS) surveys (1990–1998). modeling (Figure 4). As part of the

54 Oceanography Vol.23, No.3 synthesis phase, the ocean carbon community began collecting and quality controlling the publicly available survey data through GLODAP (Global Ocean Data Analysis Project; http://cdiac.esd.ornl.gov/oceans/glodap/ Glodap_home.htm). Complementary efforts through CARINA (Carbon Dioxide in the Atlantic Ocean; http://store.pangaea.de/Projects/ CARBOOCEAN/carina/index.htm) and PICES (North Pacific Marine Science Organization; http://www.pices.int) were started to gather and archive data sets that were not publicly available so they would not be lost to the community. The GLODAP synthesis accumulated approximately 72,000 observations collected by eight different countries over about a 10-year period. After going through an extensive quality assurance procedure, the DIC measurements were estimated to have an overall accuracy of ~ ±2 µmol kg–1, finally achieving

Broecker’s prescription (Broecker, 1979; Figure 3. Plot of the annual number of surface CO2 observations by year on a log scale (A) and on a linear scale (B). Sabine et al., 2005). However, the international community had yet to achieve 30,000 the goal of estimating the ocean carbon WOCE/JGOFS inventory to ±10–20 Pg C that it had identified nearly two decades earlier. 25,000 Despite the questions raised by the Tans et al. (1990) paper over the

vations 20,000 ocean carbon sink and the increased Repeat Hydrography emphasis on understanding the global carbon cycle for IPCC assessments, little 15,000 progress was made on quantifying the ocean carbon inventory through most 10,000 of the 1990s. Arthur Chen (National Annual Number of Obser Sun Yat-sen University) and colleagues 5,000 continued to publish regional anthropo- GEOSECS genic carbon inventories based on the controversial Chen and Millero (1978) 0 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 technique. By 1993, Chen had developed Year a DIC-based global anthropogenic CO2 Figure 4. Plot of the annual number of ocean interior CO2 observations by year.

Oceanography September 2010 55 estimate of 90 Pg C based primarily with the newly formed Global Carbon global carbon cycle. on the GEOSECS data (Chen, 1993). Project (GCP, a joint effort under the GCP recognized that the best way to However, the large uncertainties associ- International Geosphere-Biosphere facilitate interactions and collaborations ated with this work highlighted the Programme [IGBP], the World among scientists was to bring them need to improve the measurements and Climate Research Programme, and together in workshops to share infor- calculation techniques. the International Human Dimensions mation and discuss ideas. To provide While some scientists focused on Programme) to develop a pilot project comprehensive and inclusive ocean developing techniques for estimating called the International Ocean Carbon carbon involvement in the new GCP, ocean carbon uptake (e.g., Quay et al., Coordination Project (IOCCP). A participation in IOCCP activities was 1992), it was not until nearly 20 years member of the GCP steering committee, opened to all ocean carbon scientists, after the original inventory estima- author Christopher Sabine (NOAA/ led by a steering group of experts who tion techniques were introduced that a PMEL), agreed to chair the new pilot took responsibility for coordinating refinement of the anthropogenic CO2 project to help develop a new approach key areas of ocean carbon observations. inventory approach was developed to international coordination focused IOCCP also employed a bottom-up (Gruber et al., 1996; Gruber, 1998). This on implementing coordination actions approach of providing communica- revised technique together with the rather than simply providing scientific tion and coordination services for all newly developed GLODAP synthesized and technical advice. IOCCP also began existing national, regional, and global data set allowed Sabine et al. (2004) to serving as a central communication ocean carbon observation programs estimate that the total accumulation of and coordination forum to facilitate without requiring adherence to or anthropogenic CO2 between 1800 and the development of ocean carbon membership in any particular program 1994 was 118 ± 19 Pg C, just within the data products that could be integrated or strategy. Coordination activities uncertainty goals set by JGOFS and IOC with the terrestrial, atmospheric, and were built around bringing groups of prior to the global survey (Figure 5). human dimension components of the experts together for focused workshops

THE INTERNATIONAL OCEAN CARBON COORDINATION PROJECT In the early 2000s, global carbon cycle research again began to accelerate and more countries were becoming involved. The existing model of ocean carbon coordination through a small advisory panel that made recommendations to the community was not able to meet the coordination needs of the community. At one international meeting, some of the participants complained that the CO2 Panel had been showing the same slide of recommended actions for nearly 15 years, but no international group existed to actually carry out the recommended coordination activities. Figure 5. Plot of the monthly increase in atmospheric CO2 at Mauna Loa, HI (left scale). Blue boxes show the time frame and global ocean anthropogenic CO2 magni- With this incentive, the IOC-SCOR tude for the GEOSECS and WOCE/JGOFS global surveys (right scale). Data courtesy of Ocean CO2 Advisory Panel joined Scripps Institution of Oceanography and NOAA Earth System Research Laboratory

56 Oceanography Vol.23, No.3 to discuss technical coordination needs, replacing the CO2 Panel, with new terms WCRP Ocean Observations Panel to ensure the compatibility and compa- of reference approved by the SCOR for Climate (OOPC) and WMO-IOC rability of results, and to identify the Executive Council and the 23rd Session JCOMM to integrate ocean carbon gaps, duplications, and requirements for of the IOC Assembly. observation information into the meeting common global research and plans of the Global Observing Systems observational goals. COORDINATION OF for Climate in support of the United One of IOCCP’s first activities was TODAY’S OCEAN CARBON Nations Framework Convention on to organize the interior ocean carbon OBSERVATIONS Climate Change, the World Summit on measurement groups to assess their With the creation of IOCCP, IOC’s ocean Sustainable Development, the Group on current needs. The group recognized carbon programs have evolved from a Earth Observations, and other interna- that one of the shortcomings of the 12-person advisory panel to a commu- tional strategies on a regular basis. back calculation approach is that it nication and coordination service for In the seven years since its incep- only provides a single snapshot of the the ocean carbon community, with over tion, IOCCP has held 18 workshops ocean carbon inventory. It does not 200 participants from 24 countries. or meetings and has published and/ indicate how the ocean carbon storage Communication remains a core activity or co-sponsored the publication of 16 is changing with time. Working with of IOCCP, with the belief that knowing reports, guides, and strategy documents. the new international research program, “who is doing what and where” at any Through IOCCP, IOC is achieving the Climate Variability and Predictability given time is crucial for coordination. international cooperation in ocean (CLIVAR), IOCCP helped initiate an To meet this goal, IOCCP compiles and carbon observations that Roger Revelle international effort to reoccupy a subset maintains information about ocean was promoting back in 1960. of the WOCE/JGOFS lines to evaluate carbon observations being carried out in decadal changes in ocean carbon storage national, regional, and global research Repeat Hydrography (Figure 5). IOCCP also worked closely programs and provides this information Coordination of interior ocean carbon with the developing Surface Ocean- through maps, tables, news, and links measurements has been a primary Lower Atmosphere Study (SOLAS) and published in an online Ocean Carbon objective of IOC since its inception. the Integrated Marine Biogeochemistry Directory (http://www.ioccp.org). Historically, large-scale survey cruises and Ecosystem Research Program With this baseline information, IOCCP have been conducted as part of inten- (IMBER), both of which include some then brings together the community to sive field programs for a few years aspects of ocean carbon in their strate- analyze ongoing and planned activities, followed by periods with relatively few gies, requiring both technical and to ensure that the data from individual cruises. The GEOSECS program in the scientific coordination. activities is comparable (e.g., through 1970s provided a first glimpse into the After two international stakeholders’ development and use of reference biogeochemical differences between meetings, IOCCP was recognized as a materials, quality control and quality the Atlantic, Pacific, and Indian oceans. successful model for global-scale coor- assurance procedures, standard prac- The JGOFS and WOCE programs gave dination and was requested to expand tices), and that the coverage from this us the first large-scale examination of its mandate to include communication combined network is sufficient to meet the physical and ecological mechanisms and coordination services for the full research needs for basin- and global- controlling the ocean carbon cycle in range of ocean carbon variables (not just scale issues (and where it is inadequate, different regions and provided a detailed

CO2) and to assist the global, regional, to identify and prioritize needs). baseline assessment of ocean properties and national research programs as IOCCP works closely with numerous that will be used for decades to evaluate requested with coordination of research research and observation programs to long-term changes in ocean physics activities (not just large-scale observa- maintain the most up-to-date and accu- and chemistry. The WOCE/JGOFS tions). In 2005, IOC and SCOR agreed rate information possible. IOCCP also period was unprecedented in the level to make IOCCP a standing project, works directly with the GOOS-GCOS- of support and number of observations

Oceanography September 2010 57 collected (Figure 4). This level of due to global warming, an altered water basins, with operations involving more support, however, was not sustainable. cycle, and sea ice. A sustained observa- than a dozen countries (Figures 3 and 6). The drastic decrease in cruises after the tion program will help maintain a more These data, however, still are not suffi- WOCE/JGOFS field program period consistent presence of research cruises cient for directly constraining the net forced a number of analytical labs that will be able to detect changes, both annual air-sea exchange globally. As to be shut down. anticipated and unexpected, in the a result, the community is exploring It is clear that the ocean is accumu- ocean carbon cycle. additional novel platforms for collecting lating anthropogenic CO2 (Figure 5). data as well as empirical algorithms The number of new techniques proposed Surface CO2 Observations for extrapolating measurements using for estimating ocean inventories of Historically, surface CO2 observa- remotely sensed data (e.g., Watson anthropogenic CO2 has increased tions were made primarily on carbon et al., 2009). Autonomous CO2 systems substantially over the last decade (see and biogeochemistry cruises where have been designed for moorings and Sabine and Tanhua, 2010, and references the scientists for that expedition were drifters, so the expectation is that the therein). Despite numerous technological interested in surface CO2 variability. As data stream for surface observations will advances over the last several decades, the systems became more robust, they continue to grow. ship-based hydrography remains the only were frequently deployed on ships for The greatest value of these data is in method for obtaining high-quality, high extended periods and allowed to collect the large-scale patterns they reveal, so spatial and vertical resolution measure- data even when the goals of the expedi- international coordination and synthesis ments of a suite of physical, chemical, tion did not directly involve CO2. This is becoming increasingly important. At and biological parameters over the full change was made both because the large a workshop co-sponsored by IOCCP water column. Ship-based hydrography is amount of overhead involved in setting in April 2007, participants agreed to essential for documenting ocean changes up the instruments made it easier to just establish a global surface CO2 data set throughout the water column, especially leave them installed on the ship, and that would bring together, in a common for the deep ocean below 2 km (52% of because the systems could be run with format, all publicly available surface CO2 global ocean volume). minimal impact on the other ship opera- data for the ocean. The Surface Ocean

In collaboration with the international tions. These systems did, however, gener- CO2 Atlas (SOCAT) project, coordinated research programs, IOCCP is working ally require a scientist to spend some through IOCCP, has already compiled to promote a sustained, repeat, ship- time each day maintaining them. As more than six million data points based hydrography program called the further development made the systems collected on 2171 cruises by 12 countries Global Ocean Ship-based Hydrographic more autonomous and commercially between 1968 and 2007 (http://www. Investigations Program (GO-SHIP) that available, scientists started installing socat.info). A quality-controlled data set would be a component of the Global the instruments on commercial ships. should be released to the public in the Ocean/Climate Observing System This strategy significantly increased the summer of 2011. (http://www.go-ship.org). The principal options for collecting data and began to scientific objectives for repeat hydrog- provide better seasonal coverage as the Ocean Carbon Sequestration raphy have two closely linked compo- commercial ships frequently transited and Ocean Acidification nents: (1) understanding and docu- back and forth along the same routes, After the publication in 2001 of an menting large-scale ocean water property while the research ships rarely reoccu- Ocean Carbon Sequestration Watching distributions, their changes, and drivers pied the same area on a regular basis. Brief (ioc.unesco.org/iocweb/co2panel/ of those changes, and (2) addressing Surface observations have become Docs/WBprintfriendly.pdf), the questions of a future ocean that will an important part of many national IOC-SCOR Ocean CO2 Advisory Panel increase in DIC, become more acidic and and regional research agendas. Today discussed the need for an international more stratified, and experience changes more than 1.3 million observations are symposium to examine all forms of in circulation and ventilation processes made each year in all of the major ocean ocean carbon sequestration being

58 Oceanography Vol.23, No.3 proposed. During the initial planning understanding the mechanisms, magni- expected from ocean acidification (http:// for that meeting, it was suggested that tude, and time scale of ocean acidifica- www.ocean-acidification.net). a more in-depth look at the conse- tion impacts. The journal Nature recently IOC is currently working with quences of storing anthropogenic referred to this symposium as “a turning the European Project on OCean

CO2 in the ocean, including ocean point in expanding awareness among Acidification (EPOCA; http://www. acidification, should be examined. As scientists about acidification.” As of the epoca-project.eu), the US Ocean Carbon discussions continued, it became clear end of 2009, approximately 60% of the and Biogeochemistry Program (http:// that the issue of ocean acidification peer-reviewed research on ocean acidifi- www.us-ocb.org), and other national was in itself a subject that required cation had been published following the research groups to develop a Guide to immediate attention. 2004 symposium. IOC and SCOR, joined Best Practices for Ocean Acidification In May 2004, SCOR and IOC hosted by IGBP and the Marine Environmental Research and Data Reporting. IOC and an international symposium, The Ocean Laboratory of the International Atomic its partners have also started planning rd in a High CO2 World, to evaluate what Energy Agency, hosted a second sympo- for the 3 Symposium on The Ocean is known about how rising CO2 levels sium on The Ocean in a High CO2 World in a High CO2 World, scheduled for in the ocean might impact marine in 2008 at the Oceanographic Museum 2012. Although these meetings have ecosystems and services, as well as the of Monaco under the High Patronage of developed a primary focus on ocean possible benefits or impacts of ocean His Serene Highness Prince Albert II, acidification, the debate on ocean fertil-

CO2 mitigation strategies. This sympo- with 240 scientists from 32 countries ization and purposeful ocean carbon sium brought together 120 of the world’s attending. The symposium produced The storage is far from over, and IOC also leading scientists from 18 countries with Monaco Declaration with a foreword continues to address these scientific and expertise from different branches of from Prince Albert II, which called for technical issues in collaboration with marine biology, chemistry, and physics immediate action to lower CO2 concen- the International Maritime Organization to identify urgent research priorities for trations to avoid the worst of the impacts (IMO) and its London Convention.

Figure 6. Map of repeated or one-time underway surface CO2 measurements conducted during the period 2000–2009.

Oceanography September 2010 59 SUMMARY were conducted is now being redirected Brewer, P.G. 1986. What controls the variability of carbon dioxide in the surface ocean? A plea for Roger Revelle was the first to recog- toward large multinational studies of the complete information. Pp. 215–281 in Dynamic nize that understanding the gigantic mechanisms, pace, and consequences Processes in the Chemistry of the Upper Ocean. geochemical experiment being of ocean acidification resulting from J.D. Burton, P.G. Brewer, and R. Chesselet, eds, Plenum Press, New York. conducted by adding fossil fuel CO2 anthropogenic CO2 uptake, once again Broecker, W.S., T. Takahashi, H.J. Simpson, and to the ocean required an interna- under IOC and SCOR leadership. Efforts T.-H. Peng. 1979. Fate of fossil fuel carbon dioxide and the global carbon budget. tional effort of unprecedented scale, to address the ocean carbon problem Science 206:409–418. complexity, and integration. The creation stand as the signature contribution of Broecker, W.S., T. Takahashi, and T.-H. Peng. 1985. Reconstruction of Past Atmospheric of IOC in 1960 provided the platform to IOC’s first 50 years. CO2 Contents from the Chemistry of the Contemporary Ocean: An Evaluation. TR020, DOE/OR-857, US Department of Energy, 79 pp. Chen, C.-T., and F.J. Millero. 1979. Gradual

increase of oceanic CO2. Nature 277:205–206, Understanding the respective roles of doi:10.1038/277205a0. Chen, C.-T. 1993. The oceanic anthropogenic CO2 sink. Chemosphere 27:1,041–1,064. ocean physics, chemistry, and biology has been De Baar, H.J.W., P.W. Boyd, K.H. Coale, a major focus of IOC and SCOR-coordinated M.R. Landry, A. Tsuda, P. Assmy, D.C. Bakker, Y. Bozec, R.T. Barber, M.A. Brzezinski, and ocean research since the 1980s. others. 2005. Synthesis of iron fertilization “ experiments: From the Iron Age in the Age of Enlightenment: The ocean in a high-CO2 world. Journal of Geophysical Research 110(9), C09S16.1-C09S16.24 (2 p.3/4). Dickson, A.G. 2010. Standards for ocean measure- launch this effort, which grew eventu- Acknowledgements ments. Oceanography 23(3):34–47. ally to encompass over a million ocean IOC’s ocean carbon activities are funded DOE. 1994. Handbook of Methods for the Analysis ” of the Various Parameters of the Carbon Dioxide carbon system measurements annually, through IOC and SCOR, with major System in Sea Water. Version 2. A. Dickson and and laid the groundwork for a global financial support provided by the US C. Goyet, eds, Department of Energy, ORNL/ ocean observing system. Even with this National Science Foundation through a CDIAC-74. GESAMP (Group of Experts on the Scientific huge enterprise, ocean scientists needed grant to UNESCO-IOC (OCE-0715161) Aspects of Marine Environmental Protection). almost four decades to isolate and and a grant to the Scientific Committee 1997. (IMO/FAO/UNESCO-IOC/WMO/ WHO/IAEA/UN/UNEP Joint Group of accurately quantify the anthropogenic on Oceanic Research (OCE-0608600) for Experts on the Scientific Aspects of Marine Environmental Protection) Report of the component of CO2 dissolved in the IOCCP. The activities also benefit from Twenty-Seventh Session of GESAMP, Nairobi, ocean water column. generous in-kind contributions from Kenya, 14–18 April 1997. GESAMP Reports and Revelle had noted as early as 1960 NOAA and national carbon programs in Studies No. 63, 45 pp. that the ocean carbon problem had Japan and the EU. This is NOAA/PMEL GOFS. 1984. Global Ocean Flux Study. Proceedings of a workshop, Woods Hole Study Center, biological as well as geochemical dimen- publication number 3523. 10-14 September, 1984. National Academy sions. Understanding the respective Press, Washington, DC. Gruber, N. 1998. Anthropogenic CO2 in the roles of ocean physics, chemistry, and REFERENCES Atlantic Ocean. Global Biogeochemical Cycles biology has been a major focus of IOC Barnola, J.-M., D. Raynaud, Y.S. Korotkevich, 12:165–191. and C. Lorius. 1987. Vostok ice core provides Gruber, N., J.L. Sarmiento, and T.F. Stocker. 1996. and SCOR-coordinated ocean research 160,000-year record of atmospheric CO2. An improved method for detecting anthropo- Nature 329:408–414. since the 1980s. The ocean science genic CO2 in the oceans. Global Biogeochemical Bates, N.R., 2002. Interannual variability in the community has made great progress in Cycles 10:809–837. global uptake of CO2. Geophysical Research JGOFS. 1990. Joint Global Ocean Flux Study Science understanding the biological processes Letters 29(5), 1059, doi:10.1029/2001GL013571. Plan, JGOFS Report #5. SCOR, Halifax, N.S., Bolin, B., A. Bjorkstrom, K. Holmen, and B. Moore. responsible for the HNLC regions of the Canada, 61 pp. 1983. The simultaneous use of tracers for ocean JGOFS. 1994. Joint Global Ocean Flux Study Core ocean through a series of international circulation studies. Tellus B 35(3):206–236. Measurement Protocols, JGOFS Report #6. mesoscale iron addition experiments. Brewer, P.G. 1978. Direct observation of the SCOR, Halifax, N.S., Canada, 40 pp. oceanic CO2 increase. Geophysical Research The zeal with which these experiments Letters 5:997–1,000.

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