A Synthesis of Global Coastal Ocean Greenhouse Gas Fluxes

Global Biogeochemical Cycles, Journal Year: 2024, Volume and Issue: 38(1)

Published: Jan. 1, 2024

Abstract The coastal ocean contributes to regulating atmospheric greenhouse gas concentrations by taking up carbon dioxide (CO 2 ) and releasing nitrous oxide (N O) methane (CH 4 ). In this second phase of the Regional Carbon Cycle Assessment Processes (RECCAP2), we quantify global fluxes CO , N O CH using an ensemble gap‐filled observation‐based products biogeochemical models. is a net sink in both observational models, but magnitude median uptake ∼60% larger models (−0.72 vs. −0.44 PgC year −1 1998–2018, extending 300 km offshore or 1,000 m isobath with area 77 million We attribute most model‐product difference seasonality sea surface partial pressure at mid‐ high‐latitudes, where simulate stronger winter uptake. has increased past decades available time‐resolving show large discrepancies increase. major source (+0.70 PgCO ‐e product +0.54 model median) (+0.21 product), which offsets substantial proportion radiative balance (30%–60% ‐equivalents), highlighting importance considering three gases when examining influence on climate.

Language: Английский

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Global atmospheric methane uptake by upland tree woody surfaces

Nature, Journal Year: 2024, Volume and Issue: 631(8022), P. 796 - 800

Published: July 24, 2024

Abstract Methane is an important greenhouse gas 1 , but the role of trees in methane budget remains uncertain 2 . Although it has been shown that wetland and some upland can emit soil-derived at stem base 3,4 also suggested serve as a net sink for atmospheric 5,6 Here we examine situ woody surface exchange tropical, temperate boreal forest trees. We find uptake on surfaces, particular above about m floor, dominate ecosystem contribution trees, resulting tree sink. Stable carbon isotope measurement chamber air process-level investigations extracted wood cores are consistent with methanotrophy, suggesting microbially mediated drawdown surfaces tissues. By applying terrestrial laser scanning-derived allometry to quantify global area, preliminary first estimate suggests may contribute 24.6–49.9 Tg globally. Our findings indicate climate benefits tropical protection reforestation be greater than previously assumed.

Language: Английский

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The importance of plants for methane emission at the ecosystem scale

Aquatic Botany, Journal Year: 2022, Volume and Issue: 184, P. 103596 - 103596

Published: Nov. 5, 2022

Methane (CH4), one of the key long-lived atmospheric greenhouse gases, is primarily produced from organic matter. Accordingly, net primary production matter sets boundaries for CH4 emissions. Plants, being dominant producers, are thereby indirectly sustaining most global emissions, albeit with delays in time and spatial offsets between plant subsequent emission. In addition, communities can enhance or hamper ecosystem production, oxidation, transport multiple ways, e.g., by shaping carbon, nutrient, redox gradients, representing a physical link zones extensive anoxic sediments soils atmosphere. This review focuses on how plants other producers influence emissions consequences at scales. We outline mechanisms interactions discuss flux regulation, quantification, knowledge gaps across examples. Some recently proposed plant-related fluxes difficult to reconcile budget enigmas related these highlighted. Overall, strongly linked producer communities, directly indirectly, properly quantifying magnitudes regulation links predicting future rapidly changing world.

Language: Английский

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W Single‐Atom Catalyst for CH₄ Photooxidation in Water Vapor

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(33)

Published: June 29, 2022

Solar-driven high-efficiency and direct conversion of methane into high-value-added liquid oxygenates against overoxidation remains a great challenge. Herein, facile mass fabrication low-cost tungsten single-atom photocatalysts is achieved by directly calcining urea sodium tungstate under atmosphere (W-SA-PCN-m, amount m = 7.5, 15, 30, 150 g). The can manage H2 O2 in situ generation decomposition ·OH, thus achieving highly efficient CH4 photooxidation water vapor mild conditions. Systematic investigations demonstrate that integration multifunctions activation, generation, one photocatalyst dramatically promote to C1 with yield as high 4956 µmol gcat-1 , superior the most reported non-precious photocatalysts. Liquid-solid phase transition induce products facilely switch from HCOOH CH3 OH pulling catalyst above OH/HCOOH ratio 10% (in O) 80% (above O).

Language: Английский

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Evaluation of the methane paradox in four adjacent pre-alpine lakes across a trophic gradient

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: April 15, 2023

Contrasting the paradigm that methane is only produced in anoxic conditions, recent discoveries show oxic production (OMP, aka paradox) occurs oxygenated surface waters worldwide. OMP drivers and their contribution to global emissions, however, are not well constrained. In four adjacent pre-alpine lakes, we determine net rates using two mass balance approaches, accounting for sources sinks. We find three out of studied often as dominant source diffusive emissions. Correlations versus chlorophyll-a, Secchi mixed layer depths suggest a link with photosynthesis provides an empirical upscaling approach. As direct contact atmosphere, better understanding its extent necessary constrain atmospheric by inland waters.

Language: Английский

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Long‐term elevated precipitation induces grassland soil carbon loss via microbe‐plant–soil interplay

Global Change Biology, Journal Year: 2023, Volume and Issue: 29(18), P. 5429 - 5444

Published: June 14, 2023

Abstract Global climate models predict that the frequency and intensity of precipitation events will increase in many regions across world. However, biosphere‐climate feedback to elevated (eP) remains elusive. Here, we report a study on one longest field experiments assessing effects eP, alone or combination with other change drivers such as CO 2 (eCO ), warming nitrogen deposition. Soil total carbon (C) decreased after decade eP treatment, while plant root production years. To explain this asynchrony, found relative abundances fungal genes associated chitin protein degradation increased were positively correlated bacteriophage genes, suggesting potential viral shunt C degradation. In addition, microbial stress tolerance which are essential for coping environmental stressors. Microbial responses phylogenetically conserved. The soil C, production, microbes interactively affected by eCO . Collectively, demonstrate long‐term induces loss, owing changes community composition, functional traits, moisture. Our unveils an important, previously unknown Mediterranean‐type water‐limited ecosystems, namely how loss via microbe‐plant–soil interplay.

Language: Английский

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Methane formation driven by light and heat prior to the origin of life and beyond

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 1, 2023

Methane is a potent greenhouse gas, which likely enabled the evolution of life by keeping early Earth warm. Here, we demonstrate routes towards abiotic methane and ethane formation under early-earth conditions from methylated sulfur nitrogen compounds with prebiotic origin. These are demethylated in Fenton reactions governed ferrous iron reactive oxygen species (ROS) produced light heat aqueous environments. After emergence life, this phenomenon would have greatly intensified anoxic Archean providing substrates. This ROS-driven chemistry can occur delocalized serpentinization across Earth's humid realm thereby substantially differs previously suggested that spatially restricted. report driven release might shaped chemical atmosphere prior to origin beyond.

Language: Английский

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Advances in understanding of air–sea exchange and cycling of greenhouse gases in the upper ocean

Elementa Science of the Anthropocene, Journal Year: 2024, Volume and Issue: 12(1)

Published: Jan. 1, 2024

The air–sea exchange and oceanic cycling of greenhouse gases (GHG), including carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), monoxide (CO), nitrogen oxides (NOx = NO + NO2), are fundamental in controlling the evolution Earth’s atmospheric chemistry climate. Significant advances have been made over last 10 years understanding, instrumentation methods, as well deciphering production consumption pathways GHG upper ocean (including surface subsurface down to approximately 1000 m). global under current conditions is now established a major sink for CO2, source N2O minor both CH4 CO. importance or NOx largely unknown so far. There still considerable uncertainties about processes their drivers distributions N2O, CH4, CO, ocean. Without having understanding pathways, our knowledge effects ongoing changes—warming, acidification, deoxygenation, eutrophication—on remains rudimentary at best. We suggest that only through comprehensive, coordinated, interdisciplinary approach includes data collection by observation networks joint process studies can necessary be generated (1) identify relevant microbial phytoplankton communities, (2) quantify rates (3) comprehend drivers, (4) decipher economic cultural implications mitigation solutions.

Language: Английский

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Unveiling the unique role of iron in the metabolism of methanogens: A review

Environmental Research, Journal Year: 2024, Volume and Issue: 250, P. 118495 - 118495

Published: Feb. 15, 2024

Language: Английский

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Revisiting the Global Methane Cycle Through Expert Opinion

Earth s Future, Journal Year: 2024, Volume and Issue: 12(6)

Published: June 1, 2024

Abstract An accurate quantification of global methane sources and sinks is imperative for assessing realistic pathways to mitigate climate change. A key challenge quantifying the Global Methane Budget (Saunois et al., 2020, https://doi.org/10.5194/essd‐12‐1561‐2020 ) lack consistency in uncertainties between sectors. Here we provide a new perspective on bottom‐up (BU) top‐down (TD) by using an expert opinion analysis based questionnaire conducted 2021. Expectedly, experts rank highest uncertainty lowest confidence levels related natural BU budgets. Here, further reveal specific types introduce ranking system each sector. We find that source particularly driver data freshwater, vegetation, coastal/ocean sources, as well parameter wetland models. Reducing uncertainties, most notably aquatic will help balance future TD suggest partitioning over gradients human disturbance demonstrate 76.3% (75.8%–79.4%) or 561 (443–700) Tg CH 4 yr −1 emissions can be attributed moderately impacted, man‐made, artificial, fully anthropogenic 23.7% (20.6%–24.2%) 174 (115–223) low impacted sources. Finally, identify current research gaps plan action reduce Budget.

Language: Английский

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