Operationalizing marketable blue carbon

The global carbon sequestration and avoided emissions potentially achieved via blue is high (∼3% of annual greenhouse gas emissions); however, it limited by multidisciplinary interacting uncertainties spanning the social, governance, financial, technological dimensions. We compiled a transdisciplinary team experts to elucidate these challenges identify way forward. Key actions enhance as natural climate solution include improving policy legal arrangements ensure equitable sharing benefits; stewardship incorporating indigenous knowledge values; clarifying property rights; financial approaches accounting tools incorporate co-benefits; developing solutions for measuring at low cost; resolving gaps regarding cycles. Implementing operationalizing will achieve measurable changes atmospheric concentrations, provide multiple co-benefits, address national obligations associated with international agreements. IntroductionThe effects rising dioxide levels in atmosphere are compromising our oceans changing species productivity, distribution abundance through ocean warming, acidification, deoxygenation, sea-level rise.1Intergovernmental Panel on Climate Change (IPCC) Changing Ocean, Marine Ecosystems, Dependent Communities.in: Ocean Cryosphere Climate: Special Report Intergovernmental Change. Cambridge University Press, Cambridge2022: 447-588Google Scholar altered ecosystem structure functioning climatic pressures exacerbated further anthropogenic activities, such nutrient enrichment fishing.1Intergovernmental Human communities very dependent goods services they provide, occurring have consequences their wellbeing.2Scholes R. Hassan Ash N.J. Ecosystem human well-being: current state trends.in: Millennium Assessment Series. 1. Island 2005: 1-23Google Thus, sustainable society requires stabilized retention biodiversity healthy ecosystems.1Intergovernmental In restoring health, most urgent requirement has been identified tackling change, this primary cause change.3Laffoley D. Baxter J.M. Amon D.J. Currie D.E.J. Downs C.A. Hall-Spencer Harden-Davies H. Page Reid C.P. Roberts C.M. et al.Eight urgent, fundamental simultaneous steps needed restore humanity planet inaction or delay.Aquat. Conserv. Mar. Freshw. Ecosyst. 2020; 30: 194-208https://doi.org/10.1002/aqc.3182Crossref Scopus (29) Google ScholarSeveral strategies being pursued mitigate emergency keep temperature increase below 1.5°C end century. While all pathways require rapid substantial decarbonization alongside other transitions energy, transport, building sectors, increasingly recognized that “natural solutions” (NCS) an essential component any strategy.4Rogelj J. Shindell Jiang K. Fifita S. Forster P. Ginzburg V. Handa C. Kheshgi Kobayashi Kriegler E. al.Mitigation compatible context development.in: Masson-Delmotte Zhai Pörtner H.-O. Skea Shukla P.R. Pirani A. Moufouma-Okia W. Péan Pidcock Global Warming 1.5°C. An IPCC impacts warming above pre-industrial related emission pathways, strengthening response threat development, efforts eradicate poverty. Change, 2018: 93-174Google NCS encompass range habitat-management interventions reduce sequester additional estimated be capable removing 23.8 Pg from per year.5Griscom B.W. Adams Ellis P.W. Houghton R.A. Lomax G. Miteva D.A. al.Natural solutions.Proc. Natl. Acad. Sci. U.S.A. 2017; 114: 11645-11650https://doi.org/10.1073/pnas.1710465114Crossref PubMed (980) ScholarBlue refers captured stored coastal marine ecosystems, widely accepted definition includes fluxes stores biologically driven responsive management.1Intergovernmental ecosystems store significant amounts carbon, there still debate inclusion some framework.6Lovelock C.E. Duarte Dimensions emerging perspectives.Biol. Lett. 2019; 15: 20180781https://doi.org/10.1098/rsbl.2018.0781Crossref (138) Scholar,7Macreadie P.I. Anton Raven J.A. Beaumont N. Connolly R.M. Friess Kelleway J.J. Kennedy Kuwae T. Lavery P.S. al.The future Blue Carbon science.Nat. Commun. 10: 3998https://doi.org/10.1038/s41467-019-11693-wCrossref (288) Particular attention focused vegetated mangroves, saltmarshes, seagrasses due storage long-term capacity compared terrestrial forest making them among Earth’s efficient sinks.8McLeod Chmura G.L. Bouillon Salm Bjork M. al.A blueprint carbon: toward improved understanding role habitats sequestering CO2.Front. Ecol. Envir. 2011; 9: 552-560https://doi.org/10.1890/110004Crossref (1725) Scholar, 9Ouyang X. Lee S.Y. Updated estimates accumulation rates marsh sediments.Biogeosciences. 2014; 11: 5057-5071https://doi.org/10.5194/bg-11-5057-2014Crossref (156) 10Alongi D.M. mangrove forests.Carbon Management. 2012; 3: 313-322https://doi.org/10.4155/cmt.12.20Crossref (405) 11Serrano O. Lovelock B Atwood Macreadie Canto Phinn Arias-Ortiz Bai L. Baldock Bedulli al.Australian hotspots change mitigation.Nat. 4313https://doi.org/10.1038/s41467-019-12176-8Crossref (84) 12Villa Bernal B. wetlands, science practice: overview biogeochemical process, measurement methods, framework.Ecol. Eng. 2018; 115-128https://doi.org/10.1016/j.ecoleng.2017.06.037Crossref (69) scientific stocks meant already climate-mitigation potential now included policies methodologies.13Hiraishi Krug Tanabe Srivastava Baasansuren Fukuda Troxler T.G. 2013 Supplement 2006 Guidelines National Greenhouse Gas Inventories: Wetlands. IPCC, 2014Google These ecosystems—or “blue ecosystems”—also protect coasts erosion extreme weather (including flooding), bolster fisheries, support unique biodiversity, improve water quality filtering nutrients pollutants, contribute growing aquaculture eco-tourism sectors.8McLeod Scholar,14United Nations Environment Programme (UNEP)Out blue: value environment people. UNEP, 2020Google Yet, areal extent declined globally, mainly land-use over-exploitation,15Davidson N.C. How much wetland world lost? Long-term recent trends area.Mar. Res. 65: 934-941https://doi.org/10.1071/MF14173Crossref (882) profound releasing into atmosphere,16Pendleton Donato D.C. Murray B.C. Crooks Jenkins W.A. Sifleet Craft Fourqurean J.W. Kauffman J.B. Marbà al.Estimating "blue carbon" conversion degradation ecosystems.PLoS One. 7: e43542https://doi.org/10.1371/journal.pone.0043542Crossref (827) diminished contributions resilience, local communities.The supply large, large-scale protection restoration tidal marshes, ∼3% emissions.17Macreadie Costa M.D.P. T.B. Serrano solution.Nat. Rev. Earth Environ. 2021; 2: 826-839https://doi.org/10.1038/s43017-021-00224-1Crossref (58) For example, 20% world’s forests may qualify carbon-credit schemes, 10% profitable, generating US $1.2 billion year benefits.18Zeng Y. Sarira T.V. Siman Koh L.P. limits mitigation.Curr. Biol. 31: 1737-1743.e3https://doi.org/10.1016/j.cub.2021.01.070Abstract Full Text PDF (31) Matching supply, rapidly increasing demand industry government interest protecting NCS. Several major corporations—such Apple, HSBC, BHP—have announced intentions within carbon-abatement portfolio, while countries (e.g., Australia, USA, UAE) incorporated nationally determined under Paris Agreement.19Martin Landis Bryson Lynaugh Mongeau Lutz - Nationally Determined Contributions Inventory. Appendix to: Coastal Ecosystems. Opportunities Contributions. GRID Arendal, 2016Google ScholarDespite enthusiasm NCS, conservation employing carbon-based mechanisms not dramatically increased.20Saunders M.I. Doropoulos Bayraktarov Babcock R.C. Gorman Eger A.M. Vozzo M.L. Gillies C.L. Vanderklift M.A. Steven A.D.L. al.Bright spots restoration.Curr. R1500-R1510https://doi.org/10.1016/j.cub.2020.10.056Abstract (35) Converting commitments governments, private sector, others tangible outcomes hindered (challenges) currently limit realized viable sources uncertainty span finance, technical, dimensions yet remain difficult resolve both interacting. To problem, we economists, specialists, engineers, social scientists, ecologists, decision mathematicians, biogeochemists, geomorphologists, carbon-market specialists marketable propose forward addresses uncertainties, recommend priority research management ameliorate uncertainties. doing so, encourage projects highly beneficial scalable, replicable, cost effective.Major uncertaintyExamination past linked markets including offset programs, illustrate key delivery diverse activities required transformation. Challenges lack about how proposed align community values, behaviors, perceptions risk, what individual collective capacities facilitate projects.21Contreras Thomas governance carbon.J. Indian Reg. 213-234https://doi.org/10.1080/19480881.2019.1610546Crossref (4) 22Vierros Communities traditional systems providing benefits storage, livelihoods.Clim. 140: 89-100https://doi.org/10.1007/s10584-013-0920-3Crossref (34) 23Folke Traditional Social–Ecological systems.Ecol. Soc. 2004; 7https://doi.org/10.5751/ES-01237-090307Crossref present access logistics relative those systems;24Thomas gaps, critical issues, novel approaches.Ecol. Econ. 107: 22-38https://doi.org/10.1016/j.ecolecon.2014.07.028Crossref (77) also concerns where unevenly distributed whether particular reinforce and/or exacerbate inequity25Song Dressler W.H. Satizabal Fabinyi From discourse use Philippines.J. Rural Stud. 82: 184-195https://doi.org/10.1016/j.jrurstud.2021.01.008Crossref (16) Scholar,26Bennett Blythe White C.S. Campero growth justice: ten risks economy.Mar. Policy. 125: 104387https://doi.org/10.1016/j.marpol.2020.104387Crossref (62) incentives sufficient attract, harness, maintain broad participation.27Thompson B.S. Primavera J.H. Governance implementation Payments Services (PES): empirical evidence Philippines.Ecosyst. Serv. 23: 146-155https://doi.org/10.1016/j.ecoser.2016.12.007Crossref (47) should designed objective achieving meet needs28Herr von Unger Laffoley McGivern Pathways initiatives.Aquat. 27: 116-129https://doi.org/10.1002/aqc.2793Crossref (33) benefit users; indeed, success terms effective participation management.29Torabi Mata Gordon Garrard Wescott Dettmann Bekessy S.A. money trees: drives landholders' biodiverse plantings?.Glob. 2016; 1-11https://doi.org/10.1016/j.gecco.2016.03.008Crossref (22) ScholarFrom perspective, occupy intertidal subtidal zones, which often contested spaces perspective; mangroves straddle boundary between privately owned state-owned land, seaweeds can exist beyond exclusive economic zones laws conflict. Consequently, countries, confusion land tenure intersects market,28Herr who “owns” right transact credits given project: landholder, project developer, Indigenous groups, national/sub-national government? rights REDD+ Indonesia because ownership does always give carbon.30Boer H.J. operationalising Indonesia.For. Policy 86: 4-12https://doi.org/10.1016/j.forpol.2017.10.004Crossref (17) Similarly, governments apply different rules demarcating public boundaries easily circumstances modifications zone floodgates, levees, dykes affected boundaries.31Macreadie Nielsen Seymour J.R. Petrou Thomson A.C.G. Trevathan-Tackett S.M. Ralph P.J. Can manage more carbon?.Front. 206-213https://doi.org/10.1002/fee.1484Crossref (131) Transboundary issues become even challenging seaweed alkaline (carbonate bicarbonate) flows, sink spatially removed vegetation source.32Luisetti Ferrini Grilli Jickells T.D. Kroger Lorenzoni I. Milligan van der Molen Parker al.Climate action new guidance frameworks shelf seas.Nat. 4599https://doi.org/10.1038/s41467-020-18242-wCrossref (26) Furthermore, existing rarely consider affect wetlands rise climate-change factors. Planning landward retreat managing permanence occurs complex, arise.33Rogers Saintilan Megonigal J.P. Holmquist Lu Schile-Beers Zawadzki Mazumder Woodroffe C.D. Wetland controlled millennial-scale variation rise.Nature. 567: 91-95https://doi.org/10.1038/s41586-019-0951-7Crossref (195) Scholar,34Kulp Strauss B.H. New elevation data triple vulnerability flooding.Nat. 4844https://doi.org/10.1038/s41467-019-12808-zCrossref (421) overcome contractual agreements whereby parties agree lies irrespective underlying property-based rights.35Australian Government Clean Energy RegulatorCarbon Credits (Carbon Farming Initiative — Tidal Restoration Ecosystems), Methodology Determination. F2022L00046.https://www.legislation.gov.au/Details/F2022L00046Date: 2022Google ScholarThese compounded need finance investment $608–622 $1.6–3.8 trillion order scenario.36Climate (CP)Updated View Landscape Finance 2019.https://www.climatepolicyinitiative.org/publication/updated-view-on-the-global-landscape-of-climate-finance-2019Date: coronavirus 2019 (COVID-19) pandemic concomitant socio-economic crisis ostensibly make task challenging, but opportunity implement recovery stimulus plans reallocate capital” investments—including carbon. World Economic Forum $2.7 transition several “nature-positive” could return $10.1 395 million jobs 2030.37World (WEF)The nature business.in: Nature Economy Reports. (WEF), 2020https://www3.weforum.org/docs/WEF_The_Future_Of_Nature_And_Business_2020.pdfGoogle attracting investors, pipeline overall ground constrained certainty risk-return ratio, pathway, policy/legislation. created situation investible outweighing supply. This dilemma seen types nascent; receive only 3% responsible third reduction 2°C 2030.5Griscom ScholarSupply willingness develop ameliorated if was greater carbon-sequestration opportunities, challenge technical building. There ability parameterize accurately, effectively, standardized particularly during disturbances. explore relatively unknown physico-chemical cycle globally significant, carbonate production dissolution, alkalinity bicarbonate seawater) export, contribution deeper sinks.7Macreadie Tier 1 values (i.e., globally-averaged used country country-level values) drawdown (avoided sequestration) seagrass marshes,13Hiraishi 2 (nationally relevant 3 (models) few. Knowledge methane nitrous oxide degraded landscapes, rehabilitation add substantially projects; yet, recently assessment.13Hiraishi Scholar,38Kroeger K.D. Moseman-Valtierra Tang Restoring tides impounded wetlands: potent intervention.Sci. Rep. 11914https://doi.org/10.1038/s41598-017-12138-4Crossref (90) decrease sequestration, its environmental conditions over space time, change.The forward: Resolving uncertaintiesTo first step transforming landscape (Figure 1). truly transformative seeking social-equity opportunities appropriate must considered concerns.28Herr Injustices perpetuated economy,26Bennett active timely reform; integrate mitigation remains gap.21Contreras Scholar,22Vierros underscore calls concerted finds ways working across goals.39Ogar Pecl Mustonen Science embrace solve crisis.One Earth. 162-165https://doi.org/10.1016/j.oneear.2020.07.006Abstract (30) Fortunately, excellent benefits, ventures, enhancing fisheries habitat, quality, protection, well lessons learned coastal- marine-protected area underpins support.22Vierros Research meeting needs private- public-sector goals interests therefore successful adoption, longevity, ongoing legitimacy.While instances, establishing holds generate future. important lands complex tenures stakeholders farmers, lease holders, various government, owners) explicitly shared case stacking credit markets). viability enhanced pr