Deep-sea impacts of climate interventions

Science, Journal Year: 2023, Volume and Issue: 379(6636), P. 978 - 981

Published: March 10, 2023

Ocean manipulation to mitigate climate change may harm deep-sea ecosystems.

Language: Английский

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Assessing the technical aspects of ocean-alkalinity-enhancement approaches

State of the Planet, Journal Year: 2023, Volume and Issue: 2-oae2023, P. 1 - 29

Published: Nov. 27, 2023

Abstract. Ocean alkalinity enhancement (OAE) is an emerging strategy that aims to mitigate climate change by increasing the of seawater. This approach involves ocean enhance its capacity absorb and store carbon dioxide (CO2) from atmosphere. chapter presents overview technical aspects associated with full range OAE methods being pursued discusses implications for undertaking research on these approaches. Various have been developed implement OAE, including direct injection alkaline liquid into surface ocean; dispersal particles ships, platforms, or pipes; addition minerals coastal environments; electrochemical removal acid Each method has advantages challenges, such as scalability, cost effectiveness, potential environmental impacts. The choice technique may depend factors regional oceanographic conditions, source availability, engineering feasibility. considers methods, accelerated weathering limestone, liming, creation hydrated carbonates, environments. In each case, technologies are considered, best-practice drawn. social impacts will likely specific technology local context in which it deployed. Therefore, essential feasibility undertaken parallel with, informed by, wider impact assessments. While shows promise a mitigation strategy, acknowledge limitations uncertainties. Further development needed understand long-term effects, optimize techniques, address unintended consequences. should be viewed complementary extensive emission reductions, improved if operated using energy supply chains minimal CO2 emissions.

Language: Английский

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Assessment of the enhanced weathering potential of different silicate minerals to improve soil quality and sequester CO2

Frontiers in Climate, Journal Year: 2023, Volume and Issue: 4

Published: Jan. 10, 2023

Enhanced weathering is a negative emission technology that involves the spread of crushed silicate minerals and rocks on land water. When applied to agricultural soils, resulting increase in soil pH release nutrients may co-benefit plant productivity. Silicate differ their enhanced potential , i.e., for both carbon dioxide (CO 2 ) sequestration quality improvements. However, studies comparing this dual are lacking. Therefore, we compared olivine (Mg SiO 4 ), basalt, wollastonite (CaSiO 3 two novel context, anorthite (CaAl Si O 8 albite (NaAlSi ). A down-flow column experiment was designed allowing measurements soils leachate, calculations organic inorganic budgets. Our results showed comparatively high CO capture by weathering. Furthermore, per m specific surface area indicated Calculated budgets most treatments produced net emissions from likely related short duration experiment. All silicates generally improved quality, with nickel contents remaining below contamination limits. concentrations leachates olivine-amended exceeded groundwater threshold value, stressing importance monitoring leaching. We found relatively wollastonite, while be constrained The promising indicate need further quantify .

Language: Английский

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Expert review of the science underlying nature-based climate solutions

Nature Climate Change, Journal Year: 2024, Volume and Issue: 14(4), P. 402 - 406

Published: March 21, 2024

Abstract Viable nature-based climate solutions (NbCS) are needed to achieve goals expressed in international agreements like the Paris Accord. Many NbCS pathways have strong scientific foundations and can deliver meaningful benefits but effective mitigation is undermined by with less certainty. Here we couple an extensive literature review expert elicitation on 43 find that at present most used pathways, such as tropical forest conservation, a solid basis for mitigation. However, experts suggested some many carbon credit eligibility market activity, remain uncertain terms of their efficacy. Sources uncertainty include incomplete GHG measurement accounting. We recommend focusing resolving those uncertainties before broadly scaling implementation quantitative emission or sequestration plans. If appropriate, should be supported cobenefits, biodiversity food security.

Language: Английский

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Perspectives and challenges of marine carbon dioxide removal

Frontiers in Climate, Journal Year: 2025, Volume and Issue: 6

Published: Jan. 7, 2025

The Paris Agreement to limit global warming well below 2°C requires drastic reductions in greenhouse gas emissions and the balancing of any remaining by carbon dioxide removal (CDR). Due uncertainties about potential durability many land-based approaches deliver sufficient CDR, marine CDR options are receiving more interest. We present current state knowledge regarding potentials, risks, side effects as challenges associated with technical feasibility, governance, monitoring, reporting accounting covering a range biotic geochemical approaches. specifically discuss what extent comparison direct injection CO 2 into seawater, which had been proposed decades ago is now prohibited international agreements, may provide guidance for evaluating some

Language: Английский

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Review and syntheses: Ocean alkalinity enhancement and carbon dioxide removal through marine enhanced rock weathering using olivine

Biogeosciences, Journal Year: 2025, Volume and Issue: 22(2), P. 355 - 384

Published: Jan. 21, 2025

Abstract. Marine enhanced rock weathering (mERW) is increasingly receiving attention as a marine-based carbon dioxide removal (CDR) technology. The method aims to achieve ocean alkalinity enhancement (OAE) by introducing fast-weathering rocks into coastal systems. latter envisioned act large natural biogeochemical reactor, where ambient physical and biological processes can stimulate dissolution, thus generating concomitant release increasing the seawater's capacity sequester CO2. Olivine has been put forward prime candidate mineral for mERW, but at present, no peer-reviewed results are available from larger-scale field studies in areas, so information about olivine dissolution marine systems largely derived laboratory experiments. As result, key uncertainties remain concerning efficiency, CO2 sequestration potential, impact of olivine-based mERW under relevant conditions. In this review, we summarize recent research advancements bridge gap between existing real-world environment which intended take place. To end, identify parameters that govern kinetics sediments associated enable us number still with respect implementation upscaling ERW, well monitoring, reporting, verification (MRV). From our analysis, conclude current knowledge base not sufficient predict outcome situ applications. Particularly, pore-water saturation on rate question additionality generation critical unknowns. more confidently assess potential dedicated pilot conditions needed, should be conducted sufficiently spatial scale monitored long enough time temporal resolution. Additionally, analysis indicates specific sediment type application site (e.g., cohesive versus permeable) will factor applications, it significantly influencing pH, dynamics, generation. Therefore, future also target different types.

Language: Английский

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Potential of Maritime Transport for Ocean Liming and Atmospheric CO2 Removal

Frontiers in Climate, Journal Year: 2021, Volume and Issue: 3

Published: April 8, 2021

Proposals to increase ocean alkalinity may make an important contribution meeting climate change net emission targets, while also helping ameliorate the effects of acidification. However, practical feasibility spreading large amounts alkaline materials in seawater is poorly understood. In this study, potential discharging calcium hydroxide (slaked lime, SL) using existing maritime transport evaluated, at global scale and for Mediterranean Sea. The discharge SL from vessels depends on many factors, mainly their number load capacity, distance traveled along route, frequency reloading, rate. latter be constrained by localized pH wake ship, which could detrimental marine ecosystems. Based traffic data International Maritime Organization bulk carriers container ships, assuming low rates 15% deadweight capacity dedicated transport, maximum all active worldwide estimated between 1.7 4.0 Gt/year. For Sea, based detailed data, a about 186 Mt/year estimated. fleet 1,000 new ships has been discussed, with distribution 1.3 Using average literature values CO 2 removal per unit added sea, or several Gt/year, depending Since impacts environment ships' limits rate can applied, overview methodologies assessment concentration presented. A first performed three-dimensional non-reactive one-dimensional reactive fluid dynamic model simulating shrinking particle radii, shows that slurry lead variations 1 duration just few minutes.

Language: Английский

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Negative-emissions technology portfolios to meet the 1.5 °C target

Global Environmental Change, Journal Year: 2021, Volume and Issue: 67, P. 102238 - 102238

Published: Feb. 19, 2021

Our carbon-intensive economy has led to an average temperature rise of 1 °C since pre-industrial times. As a consequence, the world seen increasing droughts, significant shrinking polar ice caps, and steady sea-level rise. To stall these issues’ worsening further, we must limit global warming 1.5 °C. In addition economy’s decarbonization, this endeavour requires use negative-emissions technologies (NETs) that remove main greenhouse gas, carbon dioxide, from atmosphere. While techno-economic feasibility alone driven definition solutions, NETs’ diverse, far-reaching implications demand more holistic assessment. Here, present comprehensive framework, integrating critical performance aspects feasibility, effectiveness, side impacts, define optimal technology mix within realistic outlooks. The resulting portfolios provide useful new benchmark compare avoidance removal measures deliberately choose best path solve climate emergency.

Language: Английский

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The Sensitivity of the Marine Carbonate System to Regional Ocean Alkalinity Enhancement

Frontiers in Climate, Journal Year: 2021, Volume and Issue: 3

Published: July 8, 2021

Ocean Alkalinity Enhancement (OAE) simultaneously mitigates atmospheric concentrations of CO 2 and ocean acidification; however, no previous studies have investigated the response non-linear marine carbonate system sensitivity to alkalinity enhancement on regional scales. We hypothesise that implementations OAE can sequester more than a global implementation. To address this, we investigate physical regimes as drivers carbon-uptake potential different simulations OAE. In this idealised ocean-only set-up, total is enhanced at rate 0.25 Pmol -1 in 75-year using Max Planck Institute Model coupled HAMburg Carbon Cycle model with pre-industrial forcing. globally eight regions: Subpolar Subtropical Atlantic Pacific gyres, Indian Southern Ocean. This study reveals has capacity exceed carbon uptake by find 82–175 Pg sequestered into when regionally 156 PgC globally, compared background-state. The application most efficient, sequestering 12% Global experiment despite being applied across surface area 40 times smaller. For first time, potentials are driven pattern redistributed areas efficiencies. also show that, while becomes less sensitive all experiments responses vary depending upon background dissolved inorganic alkalinity. Furthermore, North displays previously unexpected increase high concentrations.

Language: Английский

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CO₂ capture by pumping surface acidity to the deep ocean

Energy & Environmental Science, Journal Year: 2022, Volume and Issue: 15(2), P. 786 - 798

Published: Jan. 1, 2022

Electrochemically splitting seawater and releasing the acidified effluent stream at depth could be used to artificially accelerate dissolution of deep ocean carbonate sediments enact CO 2 sequestration with storage times 300–2500 years.

Language: Английский

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