Global Biogeochemical Cycles最新文献

{"title":"Simultaneous Hot and Dry Extreme-Events Increase Wetland Methane Emissions: An Assessment of Compound Extreme-Event Impacts Using Ameriflux and FLUXNET-CH4 Site Data Sets","authors":"T. J. R. Lippmann,&nbsp;Y. van der Velde,&nbsp;K. Naudts,&nbsp;G. Hensgens,&nbsp;J. E. Vonk,&nbsp;H. Dolman","doi":"10.1029/2024GB008201","DOIUrl":"https://doi.org/10.1029/2024GB008201","url":null,"abstract":"<p>Wetlands are the largest natural source of global atmospheric methane (CH₄). Despite advances to our understanding of changes in temperature and precipitation extremes, their impacts on carbon-rich ecosystems such as wetlands, remain significantly understudied. Here, we quantify the impacts of extreme temperature, precipitation, and dry events on wetland CH₄ dynamics by investigating the effects of both compound and discrete extreme-events. We use long-term climate data to identify extreme-events and 45 eddy covariance sites data sets sourced from the FLUXNET-CH₄ database and Ameriflux project to assess impacts on wetland CH₄ emissions. These findings reveal that compound hot + dry extreme-events lead to large increases in daily CH₄ emissions. However, per event, discrete dry-only extreme-events cause the largest total decrease in CH₄ emissions, due to their long duration. Despite dry-only extreme-events leading to an overall reduction in CH₄ emissions, enhanced fluxes are often observed for the first days of dry-only extreme-events. These effects differ depending on wetland type, where marsh sites tend to be sensitive to most types of extreme-events. Lagged impacts are significant for at least the 12 months following several types of extreme-events. These findings have implications for understanding how extreme-event impacts may evolve in the context of climate change, where changes in the frequency and intensity of temperature and precipitation extreme-events are already observed. With increasing occurrences of enhanced CH₄ fluxes in response to hot-only extreme-events and hot + wet extreme-events and fewer occurrences of reduced CH₄ fluxes during cold-only extreme-events, the impact of wetland CH₄ emissions on climate warming may be increasing.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GB008201","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Changing Biological Carbon Pump of the South Atlantic Ocean","authors":"L. Delaigue,&nbsp;O. Sulpis,&nbsp;G.-J. Reichart,&nbsp;M. P. Humphreys","doi":"10.1029/2024GB008202","DOIUrl":"https://doi.org/10.1029/2024GB008202","url":null,"abstract":"<p>Global marine anthropogenic CO₂ inventories have traditionally emphasized the North Atlantic's role in the carbon cycle, while Southern hemisphere processes are less understood. The South Subtropical Convergence (SSTC) in the South Atlantic, a juncture of distinct nutrient-rich waters, offers a valuable study area for discerning the potential impacts of climate change on the ocean's biological carbon pump (C_soft). Using discrete observations from GLODAPv2.2022 and BGC-Argo at 40°S in the Atlantic Ocean from 1972 to 2023, an increase in dissolved inorganic carbon (DIC) of +1.44 ± 0.11 μmol kg⁻¹ yr⁻¹ in surface waters was observed. While anthropogenic CO₂ played a role, variations in the contribution of C_soft were observed. Discrepancies emerged in assessing C_soft based on the tracers employed: when using AOU, C_soft(AOU) recorded an increase of +0.20 ± 0.03 μmol kg⁻¹ yr⁻¹, while using nitrate as the reference, C_soft(NO3) displayed an increase of +0.85 ± 0.07 μmol kg⁻¹ yr⁻¹. Key processes such as water mass composition shifts, changes in oxygenation, remineralization in the Southern Ocean, and the challenges they pose in accurately representing the evolving C_soft are discussed. These findings highlight that while global studies primarily attribute DIC increase to anthropogenic CO₂, observations at 40°S reveal an intensified biological carbon pump, showing that regional DIC changes are more complex than previously thought and emphasizing the need for better parameterizations to compute the BCP in the marine carbon budget.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GB008202","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Mesozooplankton Growth and Reproduction on Plankton and Organic Carbon Dynamics in a Marine Biogeochemical Model","authors":"Corentin Clerc,&nbsp;Laurent Bopp,&nbsp;Fabio Benedetti,&nbsp;Nielja Knecht,&nbsp;Meike Vogt,&nbsp;Olivier Aumont","doi":"10.1029/2024GB008153","DOIUrl":"https://doi.org/10.1029/2024GB008153","url":null,"abstract":"<p>Marine mesozooplankton play an important role for marine ecosystem functioning and global biogeochemical cycles. Their size structure, varying spatially and temporally, heavily impacts biogeochemical processes and ecosystem services. Mesozooplankton exhibit size changes throughout their life cycle, affecting metabolic rates and functional traits. Despite this variability, many models oversimplify mesozooplankton as a single, unchanging size class, potentially biasing carbon flux estimates. Here, we include mesozooplankton ontogenetic growth and reproduction into a 3-dimensional global ocean biogeochemical model, PISCES-MOG, and investigate the subsequent effects on simulated mesozooplankton phenology, plankton distribution, and organic carbon export. Utilizing an ensemble of statistical predictive models calibrated with a global set of observations, we generated monthly climatologies of mesozooplankton biomass to evaluate the simulations of PISCES-MOG. Our analyses reveal that the model and observation-based biomass distributions are consistent (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>r</mi>\u0000 <mi>pearson</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${mathrm{r}}_{mathit{pearson}}$</annotation>\u0000 </semantics></math> = 0.40, total epipelagic biomass: 137 TgC from observations vs. 232 TgC in the model), with similar seasonality (later bloom as latitude increases poleward). Including ontogenetic growth in the model induced cohort dynamics and variable seasonal dynamics across mesozooplankton size classes and altered the relative contribution of carbon cycling pathways. Younger and smaller mesozooplankton transitioned to microzooplankton in PISCES-MOG, resulting in a change in particle size distribution, characterized by a decrease in large particulate organic carbon (POC) and an increase in small POC generation. Consequently, carbon export from the surface was reduced by 10%. This study underscores the importance of accounting for ontogenetic growth and reproduction in models, highlighting the interconnectedness between mesozooplankton size, phenology, and their effects on marine carbon cycling.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GB008153","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Indian Ocean Acidification and Its Driving Mechanisms Over the Last Four Decades (1980–2019)","authors":"Kunal Chakraborty,&nbsp;A. P. Joshi,&nbsp;Prasanna Kanti Ghoshal,&nbsp;Balaji Baduru,&nbsp;Vinu Valsala,&nbsp;V. V. S. S. Sarma,&nbsp;Nicolas Metzl,&nbsp;Marion Gehlen,&nbsp;Frédéric Chevallier,&nbsp;Claire Lo Monaco","doi":"10.1029/2024GB008139","DOIUrl":"https://doi.org/10.1029/2024GB008139","url":null,"abstract":"<p>This paper aims to study the changes in the Indian Ocean seawater pH in response to the changes in sea-surface temperature, sea-surface salinity, dissolved inorganic carbon (DIC), and total alkalinity (ALK) over the period 1980–2019 and its driving mechanisms using a high-resolution regional model outputs. The analysis indicates that the rate of change of declining pH in the Arabian Sea (AS), the Bay of Bengal (BoB), and the Equatorial Indian Ocean (EIO) is −0.014 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>±</mo>\u0000 </mrow>\u0000 <annotation> $pm $</annotation>\u0000 </semantics></math> 0.002, −0.014 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>±</mo>\u0000 </mrow>\u0000 <annotation> $pm $</annotation>\u0000 </semantics></math> 0.001, and −0.015 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>±</mo>\u0000 </mrow>\u0000 <annotation> $pm $</annotation>\u0000 </semantics></math> 0.001 unit dec⁻¹, respectively. Both in AS and BoB (EIO), the highest (lowest) decadal DIC trend is found during 2000–2009. The surface acidification rate has accelerated throughout the IO region during 2010–2019 compared to the previous decades. Further, our analysis indicates that El Ninõ and positive Indian Ocean Dipole events lead to an enhancement of the Indian Ocean acidification. The increasing anthropogenic CO₂ uptake by the ocean dominantly controls 80% (94.5% and 85.7%) of the net pH trend (1980–2019) in AS (BoB and EIO), whereas ocean warming controls 14.4% (13.4% and 7.0%) of pH trends in AS (BoB and EIO). The changes in ALK contribute to enhancing the pH trend of AS by 5.0%. ALK dominates after DIC in the EIO and, similar to the AS, contributes to increasing the negative pH trend by 10.7%. In contrast, it has a buffering effect in the BoB, suppressing the pH trend by −5.4%.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Off-Shelf Transport and Biogeochemical Cycling of Terrestrial Organic Carbon Along the East Siberian Continental Margin","authors":"Jannik Martens,&nbsp;Tommaso Tesi,&nbsp;Valeriy Rusakov,&nbsp;Igor Semiletov,&nbsp;Oleg Dudarev,&nbsp;Örjan Gustafsson","doi":"10.1029/2024GB008104","DOIUrl":"https://doi.org/10.1029/2024GB008104","url":null,"abstract":"<p>Continental margins receive, process and sequester most of the terrestrial organic carbon (terrOC) released into the ocean. In the Arctic, increasing fluvial discharge and collapsing permafrost are expected to enhance terrOC release and degradation, leading to ocean acidification and translocated CO₂ release to the atmosphere. However, the processes controlling terrOC transport beyond the continental shelf, and the amount of terrOC that reaches the slope and the rise are poorly described. Here we study terrOC transport to the Laptev Sea continental slope and rise by probing surface sediments with dual-isotope (δ¹³C/Δ¹⁴C) source apportionment, degradation-diagnostic terrestrial biomarkers (<i>n</i>-alkanes, <i>n</i>-alkanoic acids, lignin phenols) and ²¹⁰Pb_xs-based mass accumulation rates (MAR). The MAR-terrOC (g m⁻² yr⁻¹) decrease from 14.7 ± 12.2 on the shelf, to 7.0 ± 5.8 over the slope, to 2.3 ± 0.3 for the rise. Scaling this to the respective regimes yields that 80% of the terrOC accumulates on the shelf, while 11% and 9% of the accumulation occurs in slope and rise sediments, respectively. TerrOC remineralization is evidenced by biomarker degradation proxies (CPI of <i>n</i>-alkanes and 3,5Bd/V) indicating 40% and 60% more terrOC degradation from slope to rise, consistent with a decline in terrOC concentrations by 57%. TerrOC degradation only partially explains this decline. An updated Laptev Sea terrOC budget suggests that sediment transport dynamics such as turbidity currents may drive terrOC shelf-basin export, contributing to the observed accumulation pattern. This study quantitatively demonstrates that Arctic shelf seas are key receptor systems for remobilized terrOC, emphasizing their importance in the carbon cycle of the rapidly changing Arctic.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GB008104","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial Variability and Source Identification of Trace Elements in Aerosols From Northwest Pacific Marginal Sea, Indian Ocean and South Pacific to Antarctica","authors":"Yuncong Ge,&nbsp;Wenkai Guan,&nbsp;Kuo Hong Wong,&nbsp;Ruifeng Zhang","doi":"10.1029/2024GB008235","DOIUrl":"https://doi.org/10.1029/2024GB008235","url":null,"abstract":"<p>Aerosols continuously transport trace elements (TEs) across long distances to the ocean, fueling marine primary production and affecting global carbon cycles. Given the multiple sources and complex transport mechanisms, field investigations of aerosol TEs on a global scale are significant for understanding their role in marine biogeochemical cycles. Here, aerosol samples were collected along a 50,000-km route covering subtropical Northwest Pacific (NWP) marginal seas, Indian Ocean, Southern Ocean, Drake Passage, and South Pacific. Samples were analyzed for the concentrations of Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Tl, and Pb. Aerosol TEs were distributed heterogeneously, with significantly lower concentrations over remote oceans compared to coastal seas. Meanwhile, TE concentrations were generally high in the Indian Ocean, moderate in the Southern Ocean, and low in the South Pacific. Cr, Ni, Cu, Zn, Cd, As, and Pb were widely enriched, primarily originating from anthropogenic sources, while Al, Ti, V, Mn, Fe, and Co were mainly from crustal sources in remote oceans. Moreover, specific sources of TEs were clarified, for example, Cr and Ni were mainly from vehicle emissions. The estimated bulk TE deposition fluxes also varied spatially. For instance, the greatest deposition of Fe occurs in the NWP marginal sea, followed by the Drake Passage, Indian Ocean Sector of Southern Ocean, Pacific Sector of Southern Ocean, and South Pacific. This study contributes to a deeper understanding of the complex dynamics of aerosol TEs in the global ocean, providing valuable information for future studies and policy making regarding climate change.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142142368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of In Situ Marine Calcium Carbonate Dissolution Kinetic Measurements in the Water Column","authors":"Ben A. Cala,&nbsp;Olivier Sulpis,&nbsp;Mariette Wolthers,&nbsp;Matthew P. Humphreys","doi":"10.1029/2023GB008009","DOIUrl":"https://doi.org/10.1029/2023GB008009","url":null,"abstract":"<p>Calcium carbonate (CaCO₃) dissolution is an integral part of the ocean's carbon cycle. However, laboratory measurements and ocean alkalinity budgets disagree on the rate and loci of dissolution. In situ dissolution studies can help to bridge this gap, but so far published studies have not been utilized as a whole because they have not previously been compiled into one data set and lack carbonate system data to compare between studies. Here, we compile all published measurements of CaCO₃ dissolution rates in the water column (11 studies, 752 data points). Combining World Ocean Atlas data (temperature, salinity) with the neural network CANYON-B (carbonate system variables), we estimate seawater saturation state (Ω) for each rate measurement. We find that dissolution rates at the same Ω vary by 2 orders of magnitude. Using a machine learning approach, we show that while Ω is the main driver of dissolution rate, most variability can be attributed to differences in experimental design, above all bias due to (diffusive) transport and the synthetic or biogenic nature of CaCO₃. The compiled data set supports previous findings of a change in the mechanism driving dissolution at Ω_crit = 0.8 that separates two distinct dissolution regimes: <i>r</i>_slow = 0.29 · (1 − Ω)^0.68(±0.16) mass% day⁻¹ and <i>r</i>_fast = 2.95 · (1 − Ω)^2.2(±0.2) mass% day⁻¹. Above the saturation horizon, one study shows significant dissolution that cannot solely be explained by established theories such as zooplankton grazing and organic matter degradation. This suggests that other, non-biological factors may play a role in shallow dissolution.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023GB008009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142089901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observed APO Seasonal Cycle in the Pacific: Estimation of Autumn O2 Oceanic Emissions","authors":"Y. Tohjima,&nbsp;T. Shirai,&nbsp;M. Ishizawa,&nbsp;H. Mukai,&nbsp;T. Machida,&nbsp;M. Sasakawa,&nbsp;Y. Terao,&nbsp;K. Tsuboi,&nbsp;S. Takao,&nbsp;S. Nakaoka","doi":"10.1029/2024GB008230","DOIUrl":"https://doi.org/10.1029/2024GB008230","url":null,"abstract":"<p>In this work, we investigated the seasonal cycle of atmospheric potential oxygen (APO), a unique tracer of air-sea gas exchanges of molecular oxygen (O₂) and carbon dioxide (CO₂), expressed as APO = O₂ + 1.1 × CO₂. APO data were obtained from flask air samples collected since the late 1990s at three Japanese ground stations and on commercial cargo ships sailing between Japan and Australia/New Zealand, North America, and Southeast Asia. We also analyzed the APO spatial distribution and seasonal cycles with simulations from an atmospheric transport model using climatological oceanic O₂ fluxes from an empirical product that relate O₂ flux to ocean heat as input. Model simulations reproduced the observed APO seasonal cycles generally well, but with larger amplitudes and earlier occurrence of seasonal minima and maxima than in the observations. Moreover, the observed seasonal cycles exhibited larger APO enhancements than the simulations in autumn and early winter, especially in the North Pacific at 20°N–60°N. These enhancements remained when refining the comparison by adjusting the simulated APO peak-to-peak amplitudes and seasonal phases to the observations. This suggests additional O₂ emissions in the North Pacific, not well expressed in the air-sea O₂ fluxes used as input for our model simulations. The average autumn enhancement at 40°N–60°N was approximately twice that measured at 20°N–40°N. Confirming previous studies, our results indicate two distinct mechanisms possibly contributing to the additional oceanic O₂ emissions: outgassing from a subsurface shallow oxygen maximum at 20°N–40°N and autumn phytoplankton bloom at 40°N–60°N.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 9","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GB008230","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142089900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-Resolution Variability of the Ocean Carbon Sink","authors":"Luke Gregor,&nbsp;Jamie Shutler,&nbsp;Nicolas Gruber","doi":"10.1029/2024GB008127","DOIUrl":"https://doi.org/10.1029/2024GB008127","url":null,"abstract":"<p>Measurements of the surface ocean fugacity of carbon dioxide (<i>f</i>CO₂) provide an important constraint on the global ocean carbon sink, yet the gap-filling products developed so far to cope with the sparse observations are relatively coarse (1° × 1° by 1 month). Here, we overcome this limitation by using a novel combination of machine learning-based methods and target transformations to estimate surface ocean <i>f</i>CO₂ and the associated sea-air CO₂ fluxes (<i>F</i>CO₂) globally at a resolution of 8-day by 0.25° × 0.25° (8D) over the period 1982 through 2022. Globally, the method reconstructs <i>f</i>CO₂ with accuracy similar to that of low-resolution methods (∼19 μatm), but improves it in the coastal ocean. Although global ocean CO₂ uptake differs little, the 8D product captures 15% more variance in <i>F</i>CO₂. Most of this increase comes from the better-represented subseasonal scale variability, which is largely driven by the better-resolved variability of the winds, but also contributed to by the better-resolved <i>f</i>CO₂. The high-resolution <i>f</i>CO₂ is also capable of capturing the signal of short-lived regional events such as hurricanes. For example, the 8D product reveals that <i>f</i>CO₂ was at least 25 μatm lower in the wake of Hurricane Maria (2017), the result of a complex interplay between the decrease in temperature, the entrainment of carbon-rich waters, and an increase in primary production. By providing new insights into the role of higher frequency variations of the ocean carbon sink and the underlying processes, the 8D product fills an important gap.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 8","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GB008127","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142041539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbon and Greenhouse Gas Budgets of Europe: Trends, Interannual and Spatial Variability, and Their Drivers","authors":"Ronny Lauerwald,&nbsp;Ana Bastos,&nbsp;Matthew J. McGrath,&nbsp;Ana Maria Roxana Petrescu,&nbsp;François Ritter,&nbsp;Robbie M. Andrew,&nbsp;Antoine Berchet,&nbsp;Grégoire Broquet,&nbsp;Dominik Brunner,&nbsp;Frédéric Chevallier,&nbsp;Alessandro Cescatti,&nbsp;Sara Filipek,&nbsp;Audrey Fortems-Cheiney,&nbsp;Giovanni Forzieri,&nbsp;Pierre Friedlingstein,&nbsp;Richard Fuchs,&nbsp;Christoph Gerbig,&nbsp;Sander Houweling,&nbsp;Piyu Ke,&nbsp;Bas J. W. Lerink,&nbsp;Wanjing Li,&nbsp;Wei Li,&nbsp;Xiaojun Li,&nbsp;Ingrid Luijkx,&nbsp;Guillaume Monteil,&nbsp;Saqr Munassar,&nbsp;Gert-Jan Nabuurs,&nbsp;Prabir K. Patra,&nbsp;Philippe Peylin,&nbsp;Julia Pongratz,&nbsp;Pierre Regnier,&nbsp;Marielle Saunois,&nbsp;Mart-Jan Schelhaas,&nbsp;Marko Scholze,&nbsp;Stephen Sitch,&nbsp;Rona L. Thompson,&nbsp;Hanqin Tian,&nbsp;Aki Tsuruta,&nbsp;Chris Wilson,&nbsp;Jean-Pierre Wigneron,&nbsp;Yitong Yao,&nbsp;Sönke Zaehle,&nbsp;Philippe Ciais","doi":"10.1029/2024GB008141","DOIUrl":"https://doi.org/10.1029/2024GB008141","url":null,"abstract":"<p>In the framework of the RECCAP2 initiative, we present the greenhouse gas (GHG) and carbon (C) budget of Europe. For the decade of the 2010s, we present a bottom-up (BU) estimate of GHG net-emissions of 3.9 Pg CO₂-eq. yr⁻¹ (using a global warming potential on a 100 years horizon), which are largely dominated by fossil fuel emissions. In this decade, terrestrial ecosystems acted as a net GHG sink of 0.9 Pg CO₂-eq. yr⁻¹, dominated by a CO₂ sink that was partially counterbalanced by net emissions of CH₄ and N₂O. For CH₄ and N₂O, we find good agreement between BU and top-down (TD) estimates from atmospheric inversions. However, our BU land CO₂ sink is significantly higher than the TD estimates. We further show that decadal averages of GHG net-emissions have declined by 1.2 Pg CO₂-eq. yr⁻¹ since the 1990s, mainly due to a reduction in fossil fuel emissions. In addition, based on both data driven BU and TD estimates, we also find that the land CO₂ sink has weakened over the past two decades. A large part of the European CO₂ and C sinks is located in Northern Europe. At the same time, we find a decreasing trend in sink strength in Scandinavia, which can be attributed to an increase in forest management intensity. These are partly offset by increasing CO₂ sinks in parts of Eastern Europe and Northern Spain, attributed in part to land use change. Extensive regions of high CH₄ and N₂O emissions are mainly attributed to agricultural activities and are found in Belgium, the Netherlands and the southern UK. We further analyzed interannual variability in the GHG budgets. The drought year of 2003 shows the highest net-emissions of CO₂ and of all GHGs combined.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":"38 8","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GB008141","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141967543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}