This page has only limited features, please log in for full access.
Soil heterotrophic respiration (SHR) is important for carbon-climate feedbacks because of its sensitivity to soil carbon, climatic conditions and nutrient availability. However, available global SHR estimates have either a coarse spatial resolution or rely on simple upscaling formulations. To better quantify the global distribution of SHR and its response to climate variability, we produced a new global SHR dataset using Random Forest, up-scaling 455 point data from the Global Soil Respiration Database (SRDB 4.0) with gridded fields of climatic, edaphic and productivity. We estimated a global total SHR of PgC yr-1 over 1985-2013 with a significant increasing trend of 0.03 Pg C yr-2. Among the inputs to generate SHR products, the choice of soil moisture datasets contributes more to the difference among SHR ensemble. Water availability dominates SHR inter-annual variability (IAV) at the global scale; more precisely, temperature strongly controls the SHR IAV in tropical forests, while water availability dominates in extra-tropical forest and semi-arid regions. Our machine-learning SHR ensemble of data-driven gridded estimates and outputs from process-based models (TRENDYv6) shows agreement for a strong association between water variability and SHR IAV at the global scale, but ensemble members exhibit different ecosystem-level SHR IAV controllers. The important role of water availability in driving SHR suggests both a direct effect limiting decomposition and an indirect effect on litter available from productivity. Considering potential uncertainties remaining in our data-driven SHR datasets, we call for more scientifically-designed SHR observation network and deep-learning methods making maximum use of observation data.
Yitong Yao; Philippe Ciais; Nicolas Viovy; Wei Li; Fabio Cresto‐Aleina; Hui Yang; Emilie Joetzjer; Ben Bond‐Lamberty. A Data‐Driven Global Soil Heterotrophic Respiration Dataset and the Drivers of Its Inter‐Annual Variability. Global Biogeochemical Cycles 2021, 35, 1 .
AMA StyleYitong Yao, Philippe Ciais, Nicolas Viovy, Wei Li, Fabio Cresto‐Aleina, Hui Yang, Emilie Joetzjer, Ben Bond‐Lamberty. A Data‐Driven Global Soil Heterotrophic Respiration Dataset and the Drivers of Its Inter‐Annual Variability. Global Biogeochemical Cycles. 2021; 35 (8):1.
Chicago/Turabian StyleYitong Yao; Philippe Ciais; Nicolas Viovy; Wei Li; Fabio Cresto‐Aleina; Hui Yang; Emilie Joetzjer; Ben Bond‐Lamberty. 2021. "A Data‐Driven Global Soil Heterotrophic Respiration Dataset and the Drivers of Its Inter‐Annual Variability." Global Biogeochemical Cycles 35, no. 8: 1.
Aerosols have a dimming and cooling effect and change hydrological regimes, thus affecting carbon fluxes, which are sensitive to climate. Aerosols also scatter sunlight, which increases the fraction of diffuse radiation, increasing photosynthesis. There remains no clear conclusion whether the impact of aerosols on land carbon fluxes is larger through diffuse radiation change than through changes in other climate variables. In this study, we quantified the overall physical impacts of anthropogenic aerosols on land C fluxes and explored the contribution from each factor using a set of factorial simulations driven by climate and aerosol data from the IPSL‐CM6A‐LR experiments during 1850‐2014. A newly‐developed land surface model which distinguishes diffuse and direct radiation in canopy radiation transmission, ORCHIDEE_DF, was used. Specifically, a sub‐grid scheme was developed to distinguish the cloudy and clear sky conditions. We found that anthropogenic aerosol emissions since 1850 cumulatively enhanced the land C sink by 22.6 PgC. 78% of this C sink enhancement is contributed by aerosol‐induced increase in the diffuse radiation fraction, much larger than the effect of the aerosol‐induced dimming. The cooling of anthropogenic aerosols has different impacts in different latitudes but overall increases the global land C sink. The dominant role of diffuse radiation changes found in this study implies that future aerosol emissions may have a much stronger impacts on the C cycle through changing radiation quality than through changing climate alone. Earth system models need to consider the diffuse radiation fertilization effect to better evaluate the impacts of climate change mitigation scenarios.
Yuan Zhang; Philippe Ciais; Olivier Boucher; Fabienne Maignan; Ana Bastos; Daniel Goll; Thibaut Lurton; Nicolas Viovy; Nicolas Bellouin; Laurent Li. Disentangling the Impacts of Anthropogenic Aerosols on Terrestrial Carbon Cycle During 1850–2014. Earth's Future 2021, 9, 1 .
AMA StyleYuan Zhang, Philippe Ciais, Olivier Boucher, Fabienne Maignan, Ana Bastos, Daniel Goll, Thibaut Lurton, Nicolas Viovy, Nicolas Bellouin, Laurent Li. Disentangling the Impacts of Anthropogenic Aerosols on Terrestrial Carbon Cycle During 1850–2014. Earth's Future. 2021; 9 (7):1.
Chicago/Turabian StyleYuan Zhang; Philippe Ciais; Olivier Boucher; Fabienne Maignan; Ana Bastos; Daniel Goll; Thibaut Lurton; Nicolas Viovy; Nicolas Bellouin; Laurent Li. 2021. "Disentangling the Impacts of Anthropogenic Aerosols on Terrestrial Carbon Cycle During 1850–2014." Earth's Future 9, no. 7: 1.
Julia Bres; Pierre Sepulchre; Nicolas Viovy; Nicolas Vuichard. Supplementary material to "The Cretaceous physiological adaptation of angiosperms to a declining pCO2: a trait-oriented modelling approach". 2021, 1 .
AMA StyleJulia Bres, Pierre Sepulchre, Nicolas Viovy, Nicolas Vuichard. Supplementary material to "The Cretaceous physiological adaptation of angiosperms to a declining pCO2: a trait-oriented modelling approach". . 2021; ():1.
Chicago/Turabian StyleJulia Bres; Pierre Sepulchre; Nicolas Viovy; Nicolas Vuichard. 2021. "Supplementary material to "The Cretaceous physiological adaptation of angiosperms to a declining pCO2: a trait-oriented modelling approach"." , no. : 1.
The Cretaceous evolution of angiosperm leaves towards higher vein densities enables unprecedented leaf stomatal conductance. Still, simulating and quantifying the impact of such change on plant productivity and transpiration in the peculiar environmental conditions of the Cretaceous remains challenging. Here, we address this issue by combining a paleo proxy-based model with a fully atmosphere-vegetation model that couples stomatal conductance to carbon assimilation. Based on the fossil record, we build and evaluate three consistent pre-angiosperm vegetation parameterizations under two end-members scenarios of pCO2 (280 ppm and 1120 ppm) for the mid-Cretaceous : a reduction of hydraulic or photosynthetic capacity and a combination of both, supported by a likely coevolution of stomatal conductance and photosynthetic biochemistry. Our results suggest that decreasing hydraulic or/and photosynthetic capacities always generates a reduction of transpiration that is predominantly the result of plant productivity variations, modulated by light, water availability in the soil and atmospheric evaporative demand. The high pCO2 acts as a fertilizer on plant productivity that bolsters plant transpiration and water-use efficiency. However, we show that pre-angiosperm physiology does not allow vegetation to grow under low pCO2 because of a positive feedback between leaf stomatal conductance and leaf area index. Our modelling approach stresses the need to better represent paleovegetation physiological traits. It also confirms the hypothesis of a likely evolution of angiosperms from a stage of low hydraulic and photosynthetic capacities at high pCO2 to a stage of high hydraulic and photosynthetic capacities linked to leaves more and more densely irrigated together with a more efficient biochemistry at low pCO2.
Julia Bres; Pierre Sepulchre; Nicolas Viovy; Nicolas Vuichard. The Cretaceous physiological adaptation of angiosperms to a declining pCO2: a trait-oriented modelling approach. 2021, 2021, 1 -28.
AMA StyleJulia Bres, Pierre Sepulchre, Nicolas Viovy, Nicolas Vuichard. The Cretaceous physiological adaptation of angiosperms to a declining pCO2: a trait-oriented modelling approach. . 2021; 2021 ():1-28.
Chicago/Turabian StyleJulia Bres; Pierre Sepulchre; Nicolas Viovy; Nicolas Vuichard. 2021. "The Cretaceous physiological adaptation of angiosperms to a declining pCO2: a trait-oriented modelling approach." 2021, no. : 1-28.
Amazonian evergreen forests show distinct canopy phenology and photosynthetic seasonality but the climatic triggers are not well understood. This imposes a challenge for modeling leaf phenology and photosynthesis seasonality in land surface models (LSMs) across Amazonian evergreen forest biome. On continental scale, we tested two climatic triggers suggested by site observations, vapor pressure deficit (VPD) and short‐wave incoming radiation (SW) for defining leaf shedding and incorporated VPD‐ and SW‐triggered new canopy phenology modules in the ORCHIDEE LSM (hereafter VPD‐AP and SW‐AP versions). Our results show that both VPD and SW are plausible precursors of large scale litterfall seasonality across the basin by comparing against in situ data from 14 sites. Specially, both VPD‐AP and SW‐AP correctly capture the increases in litter fall during the early dry season, followed by a flush of new leaves with increasing photosynthetic rates during the later dry season. The VPD‐AP version performs better than the SW‐AP version in capturing a dry‐season increase of photosynthesis across the wet Amazonia areas where mean annual precipitation exceeds 2000 mm.yr‐1, consistent with previous satellite data analysis. Both VPD‐AP and SW‐AP model versions perform well in northern, central and southern Amazon regions where the SW seasonality is unimodal, but miss the seasonality of satellite GPP proxies in the eastern region off the coast of Guyana shield where SW seasonality is bimodal. Our findings imply that atmospheric dryness and sunlight availability likely explain the seasonality of leaf shedding and leaf flush processes, respectively, and consequently control canopy photosynthesis in Amazonian evergreen forest.
Xiuzhi Chen; Philippe Ciais; Fabienne Maignan; Yuan Zhang; Ana Bastos; Liyang Liu; Cédric Bacour; Lei Fan; Pierre Gentine; Daniel Goll; Julia Green; Hyungjun Kim; Laurent Li; Yi Liu; Shushi Peng; Hao Tang; Nicolas Viovy; Jean‐Pierre Wigneron; Jin Wu; Wenping Yuan; Haicheng Zhang. Vapor Pressure Deficit and Sunlight Explain Seasonality of Leaf Phenology and Photosynthesis Across Amazonian Evergreen Broadleaved Forest. Global Biogeochemical Cycles 2021, 35, 1 .
AMA StyleXiuzhi Chen, Philippe Ciais, Fabienne Maignan, Yuan Zhang, Ana Bastos, Liyang Liu, Cédric Bacour, Lei Fan, Pierre Gentine, Daniel Goll, Julia Green, Hyungjun Kim, Laurent Li, Yi Liu, Shushi Peng, Hao Tang, Nicolas Viovy, Jean‐Pierre Wigneron, Jin Wu, Wenping Yuan, Haicheng Zhang. Vapor Pressure Deficit and Sunlight Explain Seasonality of Leaf Phenology and Photosynthesis Across Amazonian Evergreen Broadleaved Forest. Global Biogeochemical Cycles. 2021; 35 (6):1.
Chicago/Turabian StyleXiuzhi Chen; Philippe Ciais; Fabienne Maignan; Yuan Zhang; Ana Bastos; Liyang Liu; Cédric Bacour; Lei Fan; Pierre Gentine; Daniel Goll; Julia Green; Hyungjun Kim; Laurent Li; Yi Liu; Shushi Peng; Hao Tang; Nicolas Viovy; Jean‐Pierre Wigneron; Jin Wu; Wenping Yuan; Haicheng Zhang. 2021. "Vapor Pressure Deficit and Sunlight Explain Seasonality of Leaf Phenology and Photosynthesis Across Amazonian Evergreen Broadleaved Forest." Global Biogeochemical Cycles 35, no. 6: 1.
In 2018 and 2019, central Europe was stricken by two consecutive extreme dry and hot summers (DH2018 and DH2019). The DH2018 had severe impacts on ecosystems and likely affected vegetation activity in the subsequent year, for example though depletion of carbon reserves or damage from drought. Such legacies from drought and heat stress can further increase vegetation susceptibility to additional hazards. Temporally compound extremes such as DH2018 and DH2019 can, therefore, result in an amplification of impacts by preconditioning effects of past disturbance legacies.Here, we evaluate how these two consecutive extreme summers impacted ecosystems in central Europe and how the vegetation responses to the first compound event (DH2018) modulated the impacts of the second (DH2019). To quantify the modulating role of vegetation responses to the impacts of each compound event, we first train a set of statistical models for the period 2001–2017 to predict the impacts of DH2018 and DH2019 on Enhanced Vegetation Index (EVI) anomalies from MODIS. These estimates can be seen as the expected EVI anomalies, had the impacts of DH2018 and DH2019 been consistent with past sensitivity to climate. These can then be used to identify modulating effects by vegetation activity and composition or other environmental factors such as elevated CO2 or warming trends.We find two regions in which the impacts of the two DH events were significantly stronger than those expected based on previous climate–vegetation relationships. One region, largely dominated by grasslands and crops, showed much stronger impacts than expected in both DH events due to an amplification of their sensitivity to heat and drought, possibly linked to changing background CO2 and temperature conditions. A second region, dominated by forests, showed browning from DH2018 to DH2019, even though dry and hot conditions were partly alleviated in 2019. This browning trajectory was mainly explained by the preconditioning role of DH2018 to the observed response to DH2019 through legacy effects, and possibly by increased susceptibility to biotic disturbances, which are also promoted by warm conditions.Dry and hot summers are expected to become more frequent in the coming decades posing a major threat to the stability of European forests. We show that state-of-the-art process based models miss these legacy effects. These gaps may result in an overestimation of the resilience and stability of temperate ecosystems in future model projections.
Ana Bastos; René Orth; Markus Reichstein; Philippe Ciais; Nicolas Viovy; Sönke Zaehle; Peter Anthoni; Almut Arneth; Pierre Gentine; Emilie Joetzjer; Sebastian Lienert; Tammas Loughran; Patrick C. McGuire; Sungmin O; Julia Pongratz; Stephen Sitch. Increased vulnerability of European ecosystems to two compound dry and hot summers in 2018 and 2019. 2021, 2021, 1 -32.
AMA StyleAna Bastos, René Orth, Markus Reichstein, Philippe Ciais, Nicolas Viovy, Sönke Zaehle, Peter Anthoni, Almut Arneth, Pierre Gentine, Emilie Joetzjer, Sebastian Lienert, Tammas Loughran, Patrick C. McGuire, Sungmin O, Julia Pongratz, Stephen Sitch. Increased vulnerability of European ecosystems to two compound dry and hot summers in 2018 and 2019. . 2021; 2021 ():1-32.
Chicago/Turabian StyleAna Bastos; René Orth; Markus Reichstein; Philippe Ciais; Nicolas Viovy; Sönke Zaehle; Peter Anthoni; Almut Arneth; Pierre Gentine; Emilie Joetzjer; Sebastian Lienert; Tammas Loughran; Patrick C. McGuire; Sungmin O; Julia Pongratz; Stephen Sitch. 2021. "Increased vulnerability of European ecosystems to two compound dry and hot summers in 2018 and 2019." 2021, no. : 1-32.
Extreme summer temperatures in western and central Europe have become more frequent and heatwaves more prolonged over the past decades. The summer of 2018 was one of the driest and hottest in the observational record and led to losses in vegetation productivity in central Europe by up to 50%. Legacy effects from such extreme summers can affect ecosystem functioning over several years, as vegetation slowly recovers. In 2019 an extremely dry and hot summer was registered again in the region, imposing stress conditions at a time when ecosystems were still recovering from summer 2018.
Using Enhanced Vegetation Index (EVI) fields from MODIS, we evaluate how ecosystems in central Europe responded to the occurrence of two consecutive extreme summers. We find that only ca. 21% of the area negatively impacted by drought in summer 2018 fully recovered in 2019.
We find that the strongest EVI anomalies in 2018/19 diverge from the long-term relationships between EVI and climate, indicating an increase in ecosystem vulnerability to heat and drought events. Furthermore, 18% of the area showed a worsening of plant status during summer 2019 in spite of drought alleviation, which could be explained by interannual legacy effects from 2018, such as impaired growth and increased biotic disturbances.
Land-surface models do not simulate interannual legacy effects from summer 2018 and thereby underestimate the impact of drought in 2019 on ecosystems. The poor representation of drought-induced damage and mortality and lack of biotic disturbances in these models may result in an overestimation of the resilience and stability of temperate ecosystems in the future.
Ana Bastos; René Orth; Markus Reichstein; Philippe Ciais; Nicolas Viovy; Sönke Zaehle; Peter Anthoni; Almut Arneth; Pierre Gentine; Emilie Joetzjer; Sebastian Lienert; Tammas Loughran; Patrick C. McGuire; Sungmin Oh; Julia Pongratz; Stephen Sitch. Increased vulnerability of European ecosystems to two consecutive extreme summers. 2021, 1 .
AMA StyleAna Bastos, René Orth, Markus Reichstein, Philippe Ciais, Nicolas Viovy, Sönke Zaehle, Peter Anthoni, Almut Arneth, Pierre Gentine, Emilie Joetzjer, Sebastian Lienert, Tammas Loughran, Patrick C. McGuire, Sungmin Oh, Julia Pongratz, Stephen Sitch. Increased vulnerability of European ecosystems to two consecutive extreme summers. . 2021; ():1.
Chicago/Turabian StyleAna Bastos; René Orth; Markus Reichstein; Philippe Ciais; Nicolas Viovy; Sönke Zaehle; Peter Anthoni; Almut Arneth; Pierre Gentine; Emilie Joetzjer; Sebastian Lienert; Tammas Loughran; Patrick C. McGuire; Sungmin Oh; Julia Pongratz; Stephen Sitch. 2021. "Increased vulnerability of European ecosystems to two consecutive extreme summers." , no. : 1.
Estimating the risk of collapse of forests due to extreme climate events is one of the challenges of adaptation to climate change. We adapt a concept from ruin theory, which is widespread in econometrics or the insurance industry, to design a growth/ruin model for trees, under climate hazards that can jeopardize their growth. This model is an elaboration of a classical Cramer-Lundberg ruin model that is used in the insurance industry. The model accounts for the interactions between physiological parameters of trees and the occurrence of climate hazards. The physiological parameters describe interannual growth rates and how trees react to hazards. The hazard parameters describe the probability distributions of occurrence and intensity of climate events. We focus on a drought/heatwave hazard. The goal of the paper is to determine the dependence of ruin and average growth probability distributions as a function of physiological and hazard parameters. From extensive Monte Carlo experiments, we show the existence of a threshold on the frequency of hazards beyond which forest ruin becomes certain in a centennial horizon. We also detect a small effect of strategies to cope with hazards. This paper is a proof-of-concept to quantify collapse (of forests) under climate change.
Pascal Yiou; Nicolas Viovy. Modelling the Ruin of Forests under Climate Hazards. 2020, 1 -21.
AMA StylePascal Yiou, Nicolas Viovy. Modelling the Ruin of Forests under Climate Hazards. . 2020; ():1-21.
Chicago/Turabian StylePascal Yiou; Nicolas Viovy. 2020. "Modelling the Ruin of Forests under Climate Hazards." , no. : 1-21.
Wenfang Xu; Jinfeng Chang; Philippe Ciais; Bertrand Guenet; Nicolas Viovy; Akihiko Ito; Christopher P. O. Reyer; Hanqin Tian; Hao Shi; Katja Frieler; Matthew Forrest; Sebastian Ostberg; Sibyll Schaphoff; Thomas Hickler. Reducing Uncertainties of Future Global Soil Carbon Responses to Climate and Land Use Change With Emergent Constraints. Global Biogeochemical Cycles 2020, 34, 1 .
AMA StyleWenfang Xu, Jinfeng Chang, Philippe Ciais, Bertrand Guenet, Nicolas Viovy, Akihiko Ito, Christopher P. O. Reyer, Hanqin Tian, Hao Shi, Katja Frieler, Matthew Forrest, Sebastian Ostberg, Sibyll Schaphoff, Thomas Hickler. Reducing Uncertainties of Future Global Soil Carbon Responses to Climate and Land Use Change With Emergent Constraints. Global Biogeochemical Cycles. 2020; 34 (10):1.
Chicago/Turabian StyleWenfang Xu; Jinfeng Chang; Philippe Ciais; Bertrand Guenet; Nicolas Viovy; Akihiko Ito; Christopher P. O. Reyer; Hanqin Tian; Hao Shi; Katja Frieler; Matthew Forrest; Sebastian Ostberg; Sibyll Schaphoff; Thomas Hickler. 2020. "Reducing Uncertainties of Future Global Soil Carbon Responses to Climate and Land Use Change With Emergent Constraints." Global Biogeochemical Cycles 34, no. 10: 1.
The Paris Climate Agreements and Sustainable Development Goals, signed by 197 countries, present agendas and address key issues for implementing multi-scale responses for sustainable development under climate change—an effort that must involve local, regional, national, and supra-national stakeholders. In that regard, Continental Carbon Sequestration (CoCS) and conservation of carbon sinks are recognized increasingly as having potentially important roles in mitigating climate change and adapting to it. Making that potential a reality will require indicators of success for various stakeholders from multidisciplinary backgrounds, plus promotion of long-term implementation of strategic action towards civil society (e.g., law and policy makers, economists, and farmers). To help meet those challenges, this discussion paper summarizes the state of the art and uncertainties regarding CoCS, taking an interdisciplinary, holistic approach toward understanding these complex issues. The first part of the paper discusses the carbon cycle’s bio-geophysical processes, while the second introduces the plurality of geographical scales to be addressed when dealing with landscape management for CoCS. The third part addresses systemic viability, vulnerability, and resilience in CoCS practices, before concluding with the need to develop inter-disciplinarity in sustainable science, participative research, and the societal implications of sustainable CoCS actions.
Tiphaine Chevallier; Maud Loireau; Romain Courault; Lydie Chapuis-Lardy; Thierry Desjardins; Cécile Gomez; Alexandre Grondin; Frédéric Guérin; Didier Orange; Raphaël Pélissier; Georges Serpantié; Marie-Hélène Durand; Pierre Derioz; Gildas Laruelle Goulven; Marie-Hélène Schwoob; Nicolas Viovy; Olivier Barrière; Eric Blanchart; Vincent Blanfort; Michel Brossard; Julien Demenois; Mireille Fargette; Thierry Heulin; Gil Mahe; Raphaël Manlay; Pascal Podwojewski; Cornélia Rumpel; Benjamin Sultan; Jean-Luc Chotte. Paris Climate Agreement: Promoting Interdisciplinary Science and Stakeholders’ Approaches for Multi-Scale Implementation of Continental Carbon Sequestration. Sustainability 2020, 12, 6715 .
AMA StyleTiphaine Chevallier, Maud Loireau, Romain Courault, Lydie Chapuis-Lardy, Thierry Desjardins, Cécile Gomez, Alexandre Grondin, Frédéric Guérin, Didier Orange, Raphaël Pélissier, Georges Serpantié, Marie-Hélène Durand, Pierre Derioz, Gildas Laruelle Goulven, Marie-Hélène Schwoob, Nicolas Viovy, Olivier Barrière, Eric Blanchart, Vincent Blanfort, Michel Brossard, Julien Demenois, Mireille Fargette, Thierry Heulin, Gil Mahe, Raphaël Manlay, Pascal Podwojewski, Cornélia Rumpel, Benjamin Sultan, Jean-Luc Chotte. Paris Climate Agreement: Promoting Interdisciplinary Science and Stakeholders’ Approaches for Multi-Scale Implementation of Continental Carbon Sequestration. Sustainability. 2020; 12 (17):6715.
Chicago/Turabian StyleTiphaine Chevallier; Maud Loireau; Romain Courault; Lydie Chapuis-Lardy; Thierry Desjardins; Cécile Gomez; Alexandre Grondin; Frédéric Guérin; Didier Orange; Raphaël Pélissier; Georges Serpantié; Marie-Hélène Durand; Pierre Derioz; Gildas Laruelle Goulven; Marie-Hélène Schwoob; Nicolas Viovy; Olivier Barrière; Eric Blanchart; Vincent Blanfort; Michel Brossard; Julien Demenois; Mireille Fargette; Thierry Heulin; Gil Mahe; Raphaël Manlay; Pascal Podwojewski; Cornélia Rumpel; Benjamin Sultan; Jean-Luc Chotte. 2020. "Paris Climate Agreement: Promoting Interdisciplinary Science and Stakeholders’ Approaches for Multi-Scale Implementation of Continental Carbon Sequestration." Sustainability 12, no. 17: 6715.
This study presents the global climate model IPSL‐CM6A‐LR developed at IPSL to study natural climate variability and climate response to natural and anthropogenic forcings as part of the 6th phase of the Coupled Model Intercomparison Project (CMIP6). This article describes the different model components, their coupling, and the simulated climate in comparison to previous model versions. We focus here on the representation of the physical climate along with the main characteristics of the global carbon cycle. The model's climatology, as assessed from a range of metrics (related in particular to radiation, temperature, precipitation, wind), is strongly improved in comparison to previous model versions. Although they are reduced, a number of known biases and shortcomings (e.g., double ITCZ, frequency of midlatitude wintertime blockings, and ENSO dynamics) persist. The equilibrium climate sensitivity and transient climate response have both increased from the previous climate model IPSL‐CM5A‐LR used in CMIP5. A large ensemble of more than 30 members for the historical period (1850‐2018) and a smaller ensemble for a range of emissions scenarios (until 2100 and 2300) are also presented and discussed.
Olivier Boucher; Jérôme Servonnat; Anna Lea Albright; Olivier Aumont; Yves Balkanski; Vladislav Bastrikov; Slimane Bekki; Rémy Bonnet; Sandrine Bony; Laurent Bopp; Pascale Braconnot; Patrick Brockmann; Patricia Cadule; Arnaud Caubel; Frederique Cheruy; Francis Codron; Anne Cozic; David Cugnet; Fabio D'andrea; Paolo Davini; Casimir De Lavergne; Sébastien Denvil; Julie Deshayes; Marion Devilliers; Agnes Ducharne; Jean‐Louis Dufresne; Eliott Dupont; Christian Éthé; Laurent Fairhead; Lola Falletti; Simona Flavoni; Marie‐Alice Foujols; Sébastien Gardoll; Guillaume Gastineau; Josefine Ghattas; Jean‐Yves Grandpeix; Bertrand Guenet; E. Guez Lionel; Eric Guilyardi; Matthieu Guimberteau; Didier Hauglustaine; Frédéric Hourdin; Abderrahmane Idelkadi; Sylvie Joussaume; Masa Kageyama; Myriam Khodri; Gerhard Krinner; Nicolas LeBas; Guillaume Levavasseur; Claire Lévy; Laurent Li; François Lott; Thibaut Lurton; Sebastiaan Luyssaert; Gurvan Madec; Jean‐Baptiste Madeleine; Fabienne Maignan; Marion Marchand; Olivier Marti; Lidia Mellul; Yann Meurdesoif; Juliette Mignot; Ionela Musat; Catherine Ottlé; Philippe Peylin; Yann Planton; Jan Polcher; Catherine Rio; Nicolas Rochetin; Clément Rousset; Pierre Sepulchre; Adriana Sima; Didier Swingedouw; Rémi Thiéblemont; Abdoul Khadre Traore; Martin Vancoppenolle; Jessica Vial; Jérôme Vialard; Nicolas Viovy; Nicolas Vuichard. Presentation and Evaluation of the IPSL‐CM6A‐LR Climate Model. Journal of Advances in Modeling Earth Systems 2020, 12, 1 .
AMA StyleOlivier Boucher, Jérôme Servonnat, Anna Lea Albright, Olivier Aumont, Yves Balkanski, Vladislav Bastrikov, Slimane Bekki, Rémy Bonnet, Sandrine Bony, Laurent Bopp, Pascale Braconnot, Patrick Brockmann, Patricia Cadule, Arnaud Caubel, Frederique Cheruy, Francis Codron, Anne Cozic, David Cugnet, Fabio D'andrea, Paolo Davini, Casimir De Lavergne, Sébastien Denvil, Julie Deshayes, Marion Devilliers, Agnes Ducharne, Jean‐Louis Dufresne, Eliott Dupont, Christian Éthé, Laurent Fairhead, Lola Falletti, Simona Flavoni, Marie‐Alice Foujols, Sébastien Gardoll, Guillaume Gastineau, Josefine Ghattas, Jean‐Yves Grandpeix, Bertrand Guenet, E. Guez Lionel, Eric Guilyardi, Matthieu Guimberteau, Didier Hauglustaine, Frédéric Hourdin, Abderrahmane Idelkadi, Sylvie Joussaume, Masa Kageyama, Myriam Khodri, Gerhard Krinner, Nicolas LeBas, Guillaume Levavasseur, Claire Lévy, Laurent Li, François Lott, Thibaut Lurton, Sebastiaan Luyssaert, Gurvan Madec, Jean‐Baptiste Madeleine, Fabienne Maignan, Marion Marchand, Olivier Marti, Lidia Mellul, Yann Meurdesoif, Juliette Mignot, Ionela Musat, Catherine Ottlé, Philippe Peylin, Yann Planton, Jan Polcher, Catherine Rio, Nicolas Rochetin, Clément Rousset, Pierre Sepulchre, Adriana Sima, Didier Swingedouw, Rémi Thiéblemont, Abdoul Khadre Traore, Martin Vancoppenolle, Jessica Vial, Jérôme Vialard, Nicolas Viovy, Nicolas Vuichard. Presentation and Evaluation of the IPSL‐CM6A‐LR Climate Model. Journal of Advances in Modeling Earth Systems. 2020; 12 (7):1.
Chicago/Turabian StyleOlivier Boucher; Jérôme Servonnat; Anna Lea Albright; Olivier Aumont; Yves Balkanski; Vladislav Bastrikov; Slimane Bekki; Rémy Bonnet; Sandrine Bony; Laurent Bopp; Pascale Braconnot; Patrick Brockmann; Patricia Cadule; Arnaud Caubel; Frederique Cheruy; Francis Codron; Anne Cozic; David Cugnet; Fabio D'andrea; Paolo Davini; Casimir De Lavergne; Sébastien Denvil; Julie Deshayes; Marion Devilliers; Agnes Ducharne; Jean‐Louis Dufresne; Eliott Dupont; Christian Éthé; Laurent Fairhead; Lola Falletti; Simona Flavoni; Marie‐Alice Foujols; Sébastien Gardoll; Guillaume Gastineau; Josefine Ghattas; Jean‐Yves Grandpeix; Bertrand Guenet; E. Guez Lionel; Eric Guilyardi; Matthieu Guimberteau; Didier Hauglustaine; Frédéric Hourdin; Abderrahmane Idelkadi; Sylvie Joussaume; Masa Kageyama; Myriam Khodri; Gerhard Krinner; Nicolas LeBas; Guillaume Levavasseur; Claire Lévy; Laurent Li; François Lott; Thibaut Lurton; Sebastiaan Luyssaert; Gurvan Madec; Jean‐Baptiste Madeleine; Fabienne Maignan; Marion Marchand; Olivier Marti; Lidia Mellul; Yann Meurdesoif; Juliette Mignot; Ionela Musat; Catherine Ottlé; Philippe Peylin; Yann Planton; Jan Polcher; Catherine Rio; Nicolas Rochetin; Clément Rousset; Pierre Sepulchre; Adriana Sima; Didier Swingedouw; Rémi Thiéblemont; Abdoul Khadre Traore; Martin Vancoppenolle; Jessica Vial; Jérôme Vialard; Nicolas Viovy; Nicolas Vuichard. 2020. "Presentation and Evaluation of the IPSL‐CM6A‐LR Climate Model." Journal of Advances in Modeling Earth Systems 12, no. 7: 1.
Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. Atmospheric emissions and concentrations of CH4 continue to increase, making CH4 the second most important human-influenced greenhouse gas in terms of climate forcing, after carbon dioxide (CO2). The relative importance of CH4 compared to CO2 depends on its shorter atmospheric lifetime, stronger warming potential, and variations in atmospheric growth rate over the past decade, the causes of which are still debated. Two major challenges in reducing uncertainties in the atmospheric growth rate arise from the variety of geographically overlapping CH4 sources and from the destruction of CH4 by short-lived hydroxyl radicals (OH). To address these challenges, we have established a consortium of multidisciplinary scientists under the umbrella of the Global Carbon Project to synthesize and stimulate new research aimed at improving and regularly updating the global methane budget. Following Saunois et al. (2016), we present here the second version of the living review paper dedicated to the decadal methane budget, integrating results of top-down studies (atmospheric observations within an atmospheric inverse-modelling framework) and bottom-up estimates (including process-based models for estimating land surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven extrapolations). For the 2008–2017 decade, global methane emissions are estimated by atmospheric inversions (a top-down approach) to be 576 Tg CH4 yr−1 (range 550–594, corresponding to the minimum and maximum estimates of the model ensemble). Of this total, 359 Tg CH4 yr−1 or ∼ 60 % is attributed to anthropogenic sources, that is emissions caused by direct human activity (i.e. anthropogenic emissions; range 336–376 Tg CH4 yr−1 or 50 %–65 %). The mean annual total emission for the new decade (2008–2017) is 29 Tg CH4 yr−1 larger than our estimate for the previous decade (2000–2009), and 24 Tg CH4 yr−1 larger than the one reported in the previous budget for 2003–2012 (Saunois et al., 2016). Since 2012, global CH4 emissions have been tracking the warmest scenarios assessed by the Intergovernmental Panel on Climate Change. Bottom-up methods suggest almost 30 % larger global emissions (737 Tg CH4 yr−1, range 594–881) than top-down inversion methods. Indeed, bottom-up estimates for natural sources such as natural wetlands, other inland water systems, and geological sources are higher than top-down estimates. The atmospheric constraints on the top-down budget suggest that at least some of these bottom-up emissions are overestimated. The latitudinal distribution of atmospheric observation-based emissions indicates a predominance of tropical emissions (∼ 65 % of the global budget, < 30∘ N) compared to mid-latitudes (∼ 30 %, 30–60∘ N) and high northern latitudes (∼ 4 %, 60–90∘ N). The most important source of uncertainty in the methane budget is attributable to natural emissions, especially those from wetlands and other inland waters. Some of our global source estimates are smaller than those in previously published budgets (Saunois et al., 2016; Kirschke et al., 2013). In particular wetland emissions are about 35 Tg CH4 yr−1 lower due to improved partition wetlands and other inland waters. Emissions from geological sources and wild animals are also found to be smaller by 7 Tg CH4 yr−1 by 8 Tg CH4 yr−1, respectively. However, the overall discrepancy between bottom-up and top-down estimates has been reduced by only 5 % compared to Saunois et al. (2016), due to a higher estimate of emissions from inland waters, highlighting the need for more detailed research on emissions factors. Priorities for improving the methane budget include (i) a global, high-resolution map of water-saturated soils and inundated areas emitting methane based on a robust classification of different types of emitting habitats; (ii) further development of process-based models for inland-water emissions; (iii) intensification of methane observations at local scales (e.g., FLUXNET-CH4 measurements) and urban-scale monitoring to constrain bottom-up land surface models, and at regional scales (surface networks and satellites) to constrain atmospheric inversions; (iv) improvements of transport models and the representation of photochemical sinks in top-down inversions; and (v) development of a 3D variational inversion system using isotopic and/or co-emitted species such as ethane to improve source partitioning. The data presented here can be downloaded from https://doi.org/10.18160/GCP-CH4-2019 (Saunois et al., 2020) and from the Global Carbon Project.
Marielle Saunois; Ann R. Stavert; Ben Poulter; Philippe Bousquet; Josep G. Canadell; Robert B. Jackson; Peter A. Raymond; Edward J. Dlugokencky; Sander Houweling; Prabir K. Patra; Philippe Ciais; Vivek K. Arora; David Bastviken; Peter Bergamaschi; Donald R. Blake; Gordon Brailsford; Lori Bruhwiler; Kimberly M. Carlson; Mark Carrol; Simona Castaldi; Naveen Chandra; Cyril Crevoisier; Patrick M. Crill; Kristofer Covey; Charles L. Curry; Giuseppe Etiope; Christian Frankenberg; Nicola Gedney; Michaela I. Hegglin; Lena Höglund-Isaksson; Gustaf Hugelius; Misa Ishizawa; Akihiko Ito; Greet Janssens-Maenhout; Katherine M. Jensen; Fortunat Joos; Thomas Kleinen; Paul B. Krummel; Ray L. Langenfelds; Goulven G. Laruelle; Licheng Liu; Toshinobu Machida; Shamil Maksyutov; Kyle C. McDonald; Joe McNorton; Paul A. Miller; Joe R. Melton; Isamu Morino; Jurek Müller; Fabiola Murguia-Flores; Vaishali Naik; Yosuke Niwa; Sergio Noce; Simon O'Doherty; Robert J. Parker; Changhui Peng; Shushi Peng; Glen P. Peters; Catherine Prigent; Ronald Prinn; Michel Ramonet; Pierre Regnier; William J. Riley; Judith A. Rosentreter; Arjo Segers; Isobel J. Simpson; Hao Shi; Steven J. Smith; L. Paul Steele; Brett F. Thornton; Hanqin Tian; Yasunori Tohjima; Francesco N. Tubiello; Aki Tsuruta; Nicolas Viovy; Apostolos Voulgarakis; Thomas S. Weber; Michiel van Weele; Guido R. van der Werf; Ray F. Weiss; Doug Worthy; Debra Wunch; Yi Yin; Yukio Yoshida; Wenxin Zhang; Zhen Zhang; Yuanhong Zhao; Bo Zheng; Qing Zhu; Qiuan Zhu; Qianlai Zhuang. The Global Methane Budget 2000–2017. Earth System Science Data 2020, 12, 1561 -1623.
AMA StyleMarielle Saunois, Ann R. Stavert, Ben Poulter, Philippe Bousquet, Josep G. Canadell, Robert B. Jackson, Peter A. Raymond, Edward J. Dlugokencky, Sander Houweling, Prabir K. Patra, Philippe Ciais, Vivek K. Arora, David Bastviken, Peter Bergamaschi, Donald R. Blake, Gordon Brailsford, Lori Bruhwiler, Kimberly M. Carlson, Mark Carrol, Simona Castaldi, Naveen Chandra, Cyril Crevoisier, Patrick M. Crill, Kristofer Covey, Charles L. Curry, Giuseppe Etiope, Christian Frankenberg, Nicola Gedney, Michaela I. Hegglin, Lena Höglund-Isaksson, Gustaf Hugelius, Misa Ishizawa, Akihiko Ito, Greet Janssens-Maenhout, Katherine M. Jensen, Fortunat Joos, Thomas Kleinen, Paul B. Krummel, Ray L. Langenfelds, Goulven G. Laruelle, Licheng Liu, Toshinobu Machida, Shamil Maksyutov, Kyle C. McDonald, Joe McNorton, Paul A. Miller, Joe R. Melton, Isamu Morino, Jurek Müller, Fabiola Murguia-Flores, Vaishali Naik, Yosuke Niwa, Sergio Noce, Simon O'Doherty, Robert J. Parker, Changhui Peng, Shushi Peng, Glen P. Peters, Catherine Prigent, Ronald Prinn, Michel Ramonet, Pierre Regnier, William J. Riley, Judith A. Rosentreter, Arjo Segers, Isobel J. Simpson, Hao Shi, Steven J. Smith, L. Paul Steele, Brett F. Thornton, Hanqin Tian, Yasunori Tohjima, Francesco N. Tubiello, Aki Tsuruta, Nicolas Viovy, Apostolos Voulgarakis, Thomas S. Weber, Michiel van Weele, Guido R. van der Werf, Ray F. Weiss, Doug Worthy, Debra Wunch, Yi Yin, Yukio Yoshida, Wenxin Zhang, Zhen Zhang, Yuanhong Zhao, Bo Zheng, Qing Zhu, Qiuan Zhu, Qianlai Zhuang. The Global Methane Budget 2000–2017. Earth System Science Data. 2020; 12 (3):1561-1623.
Chicago/Turabian StyleMarielle Saunois; Ann R. Stavert; Ben Poulter; Philippe Bousquet; Josep G. Canadell; Robert B. Jackson; Peter A. Raymond; Edward J. Dlugokencky; Sander Houweling; Prabir K. Patra; Philippe Ciais; Vivek K. Arora; David Bastviken; Peter Bergamaschi; Donald R. Blake; Gordon Brailsford; Lori Bruhwiler; Kimberly M. Carlson; Mark Carrol; Simona Castaldi; Naveen Chandra; Cyril Crevoisier; Patrick M. Crill; Kristofer Covey; Charles L. Curry; Giuseppe Etiope; Christian Frankenberg; Nicola Gedney; Michaela I. Hegglin; Lena Höglund-Isaksson; Gustaf Hugelius; Misa Ishizawa; Akihiko Ito; Greet Janssens-Maenhout; Katherine M. Jensen; Fortunat Joos; Thomas Kleinen; Paul B. Krummel; Ray L. Langenfelds; Goulven G. Laruelle; Licheng Liu; Toshinobu Machida; Shamil Maksyutov; Kyle C. McDonald; Joe McNorton; Paul A. Miller; Joe R. Melton; Isamu Morino; Jurek Müller; Fabiola Murguia-Flores; Vaishali Naik; Yosuke Niwa; Sergio Noce; Simon O'Doherty; Robert J. Parker; Changhui Peng; Shushi Peng; Glen P. Peters; Catherine Prigent; Ronald Prinn; Michel Ramonet; Pierre Regnier; William J. Riley; Judith A. Rosentreter; Arjo Segers; Isobel J. Simpson; Hao Shi; Steven J. Smith; L. Paul Steele; Brett F. Thornton; Hanqin Tian; Yasunori Tohjima; Francesco N. Tubiello; Aki Tsuruta; Nicolas Viovy; Apostolos Voulgarakis; Thomas S. Weber; Michiel van Weele; Guido R. van der Werf; Ray F. Weiss; Doug Worthy; Debra Wunch; Yi Yin; Yukio Yoshida; Wenxin Zhang; Zhen Zhang; Yuanhong Zhao; Bo Zheng; Qing Zhu; Qiuan Zhu; Qianlai Zhuang. 2020. "The Global Methane Budget 2000–2017." Earth System Science Data 12, no. 3: 1561-1623.
During the early to middle Holocene, the Sahara received enhanced precipitation and was covered by steppe-like vegetation with a large-scale hydrographic network of lakes, wetlands and fans, which is known as the Green Sahara (GS). However, most coupled land-atmosphere models underestimate the precipitation and vegetation cover, suggesting that critical atmospheric or land surface processes are lacking in those models. Climate-induced vegetation cover change can modify soil texture and physical properties over the long term, which in turn have feedbacks on vegetation. In this study, we examine five plausible soil-vegetation processes in a land surface model, which are expected to increase soil moisture for plants and possibly sustain equilibrium vegetation for a lower rainfall level. The annual precipitation required during the GS epoch to match the modelled vegetation distribution with paleorecords is inferred. Results demonstrate that these soil-vegetation processes have strong positive impacts on vegetation and soil moisture, especially the increase of soil evaporative resistance. After including all soil feedbacks on vegetation, the model requires only a mean precipitation of ∼400 mm/yr to reproduce the pollen-inferred GS vegetation, instead of ∼600 mm/yr when no soil feedback is included. From the mid-Holocene to pre-industrial period, we infer that terrestrial carbon stocks decrease by ∼58 PgC due to the removal of carbon in vegetation, soil and litter pools of the GS. This work highlights the importance of soil-vegetation interactions for simulating dry-region vegetation coverage in models, and the impacts of natural land cover change on carbon budgets in the geological past.
Weizhe Chen; Philippe Ciais; Dan Zhu; Agnès Ducharne; Nicolas Viovy; Chunjing Qiu; Chunju Huang. Feedbacks of soil properties on vegetation during the Green Sahara period. Quaternary Science Reviews 2020, 240, 106389 .
AMA StyleWeizhe Chen, Philippe Ciais, Dan Zhu, Agnès Ducharne, Nicolas Viovy, Chunjing Qiu, Chunju Huang. Feedbacks of soil properties on vegetation during the Green Sahara period. Quaternary Science Reviews. 2020; 240 ():106389.
Chicago/Turabian StyleWeizhe Chen; Philippe Ciais; Dan Zhu; Agnès Ducharne; Nicolas Viovy; Chunjing Qiu; Chunju Huang. 2020. "Feedbacks of soil properties on vegetation during the Green Sahara period." Quaternary Science Reviews 240, no. : 106389.
In summer 2018, central and northern Europe were stricken by extreme drought and heat (DH2018). The DH2018 differed from previous events in being preceded by extreme spring warming and brightening, but moderate rainfall deficits, yet registering the fastest transition between wet winter conditions and extreme summer drought. Using 11 vegetation models, we show that spring conditions promoted increased vegetation growth, which, in turn, contributed to fast soil moisture depletion, amplifying the summer drought. We find regional asymmetries in summer ecosystem carbon fluxes: increased (reduced) sink in the northern (southern) areas affected by drought. These asymmetries can be explained by distinct legacy effects of spring growth and of water-use efficiency dynamics mediated by vegetation composition, rather than by distinct ecosystem responses to summer heat/drought. The asymmetries in carbon and water exchanges during spring and summer 2018 suggest that future land-management strategies could influence patterns of summer heat waves and droughts under long-term warming.
A. Bastos; P. Ciais; P. Friedlingstein; S. Sitch; J. Pongratz; L. Fan; J. P. Wigneron; U. Weber; M. Reichstein; Z. Fu; P. Anthoni; A. Arneth; V. Haverd; A. K. Jain; E. Joetzjer; J. Knauer; S. Lienert; T. Loughran; P. C. McGuire; H. Tian; N. Viovy; S. Zaehle. Direct and seasonal legacy effects of the 2018 heat wave and drought on European ecosystem productivity. Science Advances 2020, 6, eaba2724 .
AMA StyleA. Bastos, P. Ciais, P. Friedlingstein, S. Sitch, J. Pongratz, L. Fan, J. P. Wigneron, U. Weber, M. Reichstein, Z. Fu, P. Anthoni, A. Arneth, V. Haverd, A. K. Jain, E. Joetzjer, J. Knauer, S. Lienert, T. Loughran, P. C. McGuire, H. Tian, N. Viovy, S. Zaehle. Direct and seasonal legacy effects of the 2018 heat wave and drought on European ecosystem productivity. Science Advances. 2020; 6 (24):eaba2724.
Chicago/Turabian StyleA. Bastos; P. Ciais; P. Friedlingstein; S. Sitch; J. Pongratz; L. Fan; J. P. Wigneron; U. Weber; M. Reichstein; Z. Fu; P. Anthoni; A. Arneth; V. Haverd; A. K. Jain; E. Joetzjer; J. Knauer; S. Lienert; T. Loughran; P. C. McGuire; H. Tian; N. Viovy; S. Zaehle. 2020. "Direct and seasonal legacy effects of the 2018 heat wave and drought on European ecosystem productivity." Science Advances 6, no. 24: eaba2724.
The Cretaceous angiosperm radiation was a major event for terrestrial plant evolution, and flowering plants represent more than 94 % of present-day plant diversity. The fossil record shows that angiosperm leaf vein densities reached particularly high values (> 12 mm/mm2)between the Albian and the Cenomanian (108–94 Ma) compared to gymnosperms (~ 2.5 mm/mm2). Empirical modelsalso suggest that stomatal conductance to water vapour increases as a response to higher leaf vein densities. How much do this shift to higher values of stomatal conductance have modified the continental transpiration budget,and ultimately global hydrological cycle ? To address this question we used the IPSL coupled atmosphere-vegetation model forced by Cretaceous boundary conditions, and built plant functional types includingstomatal conductance values consistent with the fossil record. We quantify the transpiration fluxes through different sensitivity experiments and explore the vegetation-atmosphere feedbacks and their impact on the Cretaceous climate.
Julia Bres; Pierre Sepulchre; Nicolas Vuichard; Nicolas Viovy. Did the rise of highly-transpiring angiosperms influenced Cretaceous climate ? A modelling approach with the IPSL atmosphere-land surface model. 2020, 1 .
AMA StyleJulia Bres, Pierre Sepulchre, Nicolas Vuichard, Nicolas Viovy. Did the rise of highly-transpiring angiosperms influenced Cretaceous climate ? A modelling approach with the IPSL atmosphere-land surface model. . 2020; ():1.
Chicago/Turabian StyleJulia Bres; Pierre Sepulchre; Nicolas Vuichard; Nicolas Viovy. 2020. "Did the rise of highly-transpiring angiosperms influenced Cretaceous climate ? A modelling approach with the IPSL atmosphere-land surface model." , no. : 1.
Agriculture is intimately affected by climate change (atmospheric CO2 concentration, temperature, precipitation and patterns of climate extremes), and there are major societal concerns about climate change effects on agriculture lands and hence food security in the 21st century. Despite those concerns, there is still only poor understanding of the possible impacts of climate change on the productivity and carbon dynamics of rain-fed pastoral systems in France, particularly their direction and magnitude over long time scales. The present study uses 3 scenarios (e.g. RCP 2.6, 4.5 and 8.5) of possible future climatic conditions and assesses their effects on productivity and SOC stocks of mowed and rotationally grazed grasslands. We used the CenW ecosystem model to simulate carbon, water, and nitrogen cycles in response to changes in environmental drivers and management practices. The simulations indicated that grassland productivity was increased through CO2 fertilization and higher water use efficiencies but that SOC losses between 5% and 23% (if CO2 fertilization is not accounted for in the simulations) are expected due to higher temperatures and biomass exports. Such losses may further affect climate feedback loop and jeopardize the agroecosystem sustainability. More extreme climate events were expected under more pessimistic climate change scenarios with very different outcomes if the CO2 fertilization effect is accounted for or not. This study showed that under the current management practices implemented at the study site, soil C losses were expected over the 21st century under climate change conditions, highlighting the need to modify/adapt farming practices.
Nicolas Puche; Nicolas Viovy; Miko Kirschbaum; Abad Chabbi. Projections of climate change effects on pasture productivity, GHG exchanges and soil carbon stocks. 2020, 1 .
AMA StyleNicolas Puche, Nicolas Viovy, Miko Kirschbaum, Abad Chabbi. Projections of climate change effects on pasture productivity, GHG exchanges and soil carbon stocks. . 2020; ():1.
Chicago/Turabian StyleNicolas Puche; Nicolas Viovy; Miko Kirschbaum; Abad Chabbi. 2020. "Projections of climate change effects on pasture productivity, GHG exchanges and soil carbon stocks." , no. : 1.
Multi-species grasslands are reservoirs of biodiversity and provide multiple ecosystem services, including fodder production and carbon sequestration. The provision of these services depends on the control exerted on the biogeochemistry and plant diversity of the system by the interplay of biotic and abiotic factors, e.g., grazing or mowing intensity. Biogeochemical models incorporate a mechanistic view of the functioning of grasslands and provide a sound basis for studying the underlying processes. However, in these models, the simulation of biogeochemical cycles is generally not coupled to simulation of plant species dynamics, which leads to considerable uncertainty about the quality of predictions. Ecological models, on the other hand, do account for biodiversity with approaches adopted from plant demography, but without linking the dynamics of plant species to the biogeochemical processes occurring at the community level, and this hampers the models’ capacity to assess resilience against abiotic stresses such as drought and nutrient limitation. While setting out the state-of-the-art developments of biogeochemical and ecological modelling, we explore and highlight the role of plant diversity in the regulation of the ecosystem processes underlying the ecosystems services provided by multi-species grasslands. An extensive literature and model survey was carried out with an emphasis on technically advanced models reconciling biogeochemistry and biodiversity, which are readily applicable to managed grasslands in temperate latitudes. We propose a roadmap of promising developments in modelling.
Marcel Van Oijen; Zoltán Barcza; Roberto Confalonieri; Panu Korhonen; György Kröel-Dulay; Eszter Lellei-Kovács; Gaëtan Louarn; Frédérique Louault; Raphaël Martin; Thibault Moulin; Ermes Movedi; Catherine Picon-Cochard; Susanne Rolinski; Nicolas Viovy; Stephen Björn Wirth; Gianni Bellocchi. Incorporating Biodiversity into Biogeochemistry Models to Improve Prediction of Ecosystem Services in Temperate Grasslands: Review and Roadmap. Agronomy 2020, 10, 259 .
AMA StyleMarcel Van Oijen, Zoltán Barcza, Roberto Confalonieri, Panu Korhonen, György Kröel-Dulay, Eszter Lellei-Kovács, Gaëtan Louarn, Frédérique Louault, Raphaël Martin, Thibault Moulin, Ermes Movedi, Catherine Picon-Cochard, Susanne Rolinski, Nicolas Viovy, Stephen Björn Wirth, Gianni Bellocchi. Incorporating Biodiversity into Biogeochemistry Models to Improve Prediction of Ecosystem Services in Temperate Grasslands: Review and Roadmap. Agronomy. 2020; 10 (2):259.
Chicago/Turabian StyleMarcel Van Oijen; Zoltán Barcza; Roberto Confalonieri; Panu Korhonen; György Kröel-Dulay; Eszter Lellei-Kovács; Gaëtan Louarn; Frédérique Louault; Raphaël Martin; Thibault Moulin; Ermes Movedi; Catherine Picon-Cochard; Susanne Rolinski; Nicolas Viovy; Stephen Björn Wirth; Gianni Bellocchi. 2020. "Incorporating Biodiversity into Biogeochemistry Models to Improve Prediction of Ecosystem Services in Temperate Grasslands: Review and Roadmap." Agronomy 10, no. 2: 259.
Changes in rainfall amounts and patterns have been observed and are expected to continue in the near future with potentially significant ecological and societal consequences. Modelling vegetation responses to changes in rainfall is thus crucial to project water and carbon cycles in the future. In this study, we present the results of a new model‐data intercomparison project, where we tested the ability of ten terrestrial biosphere models to reproduce observed sensitivity of ecosystem productivity to rainfall changes at ten sites across the globe, in nine of which, rainfall exclusion and/or irrigation experiments had been performed. The key results are: (a) Inter‐model variation is generally large and model agreement varies with time scales. In severely water limited sites, models only agree on the interannual variability of evapotranspiration and to a smaller extent gross primary productivity. In more mesic sites model agreement for both water and carbon fluxes is typically higher on fine (daily‐monthly) time scales and reduces on longer (seasonal‐annual) scales. (b) Models on average overestimate the relationship between ecosystem productivity and mean rainfall amounts across sites (in space) and have a low capacity in reproducing the temporal (interannual) sensitivity of vegetation productivity to annual rainfall at a given site, even though observation uncertainty is comparable to inter‐model variability. (c) Most models reproduced the sign of the observed patterns in productivity changes in rainfall manipulation experiments but had a low capacity in reproducing the observed magnitude of productivity changes. Models better reproduced the observed productivity responses due to rainfall exclusion than addition. (d) All models attribute ecosystem productivity changes to the intensity of vegetation stress and peak leaf area, whereas the impact of the change in growing season length is negligible. The relative contribution of the peak leaf area and vegetation stress intensity was highly variable among models.
Athanasios Paschalis; Simone Fatichi; Jakob Zscheischler; Philippe Ciais; Michael Bahn; Lena Boysen; Jinfeng Chang; Martin De Kauwe; Marc Estiarte; Daniel Goll; Paul J. Hanson; Anna B. Harper; Enqing Hou; Jaime Kigel; Alan K. Knapp; Klaus Steenberg Larsen; Wei Li; Sebastian Lienert; Yiqi Luo; Patrick Meir; Julia E. M. S. Nabel; Romà Ogaya; Anthony J. Parolari; Changhui Peng; Josep Peñuelas; Julia Pongratz; Serge Rambal; Inger Kappel Schmidt; Hao Shi; Marcelo Sternberg; Hanqin Tian; Elisabeth Tschumi; Anna Ukkola; Sara Vicca; Nicolas Viovy; Yingping Wang; Zhuonan Wang; Karina Williams; Donghai Wu; Qiuan Zhu. Rainfall manipulation experiments as simulated by terrestrial biosphere models: Where do we stand? Global Change Biology 2020, 26, 3336 -3355.
AMA StyleAthanasios Paschalis, Simone Fatichi, Jakob Zscheischler, Philippe Ciais, Michael Bahn, Lena Boysen, Jinfeng Chang, Martin De Kauwe, Marc Estiarte, Daniel Goll, Paul J. Hanson, Anna B. Harper, Enqing Hou, Jaime Kigel, Alan K. Knapp, Klaus Steenberg Larsen, Wei Li, Sebastian Lienert, Yiqi Luo, Patrick Meir, Julia E. M. S. Nabel, Romà Ogaya, Anthony J. Parolari, Changhui Peng, Josep Peñuelas, Julia Pongratz, Serge Rambal, Inger Kappel Schmidt, Hao Shi, Marcelo Sternberg, Hanqin Tian, Elisabeth Tschumi, Anna Ukkola, Sara Vicca, Nicolas Viovy, Yingping Wang, Zhuonan Wang, Karina Williams, Donghai Wu, Qiuan Zhu. Rainfall manipulation experiments as simulated by terrestrial biosphere models: Where do we stand? Global Change Biology. 2020; 26 (6):3336-3355.
Chicago/Turabian StyleAthanasios Paschalis; Simone Fatichi; Jakob Zscheischler; Philippe Ciais; Michael Bahn; Lena Boysen; Jinfeng Chang; Martin De Kauwe; Marc Estiarte; Daniel Goll; Paul J. Hanson; Anna B. Harper; Enqing Hou; Jaime Kigel; Alan K. Knapp; Klaus Steenberg Larsen; Wei Li; Sebastian Lienert; Yiqi Luo; Patrick Meir; Julia E. M. S. Nabel; Romà Ogaya; Anthony J. Parolari; Changhui Peng; Josep Peñuelas; Julia Pongratz; Serge Rambal; Inger Kappel Schmidt; Hao Shi; Marcelo Sternberg; Hanqin Tian; Elisabeth Tschumi; Anna Ukkola; Sara Vicca; Nicolas Viovy; Yingping Wang; Zhuonan Wang; Karina Williams; Donghai Wu; Qiuan Zhu. 2020. "Rainfall manipulation experiments as simulated by terrestrial biosphere models: Where do we stand?" Global Change Biology 26, no. 6: 3336-3355.
Leaf phenology in the humid tropics largely regulates the seasonality of forest carbon and water exchange. However, it is inadequately represented in most global land surface models due to limited understanding of its controls. Based on intensive field studies at four Amazonian evergreen forests, we propose a novel, quantitative representation of tropical forest leaf phenology, which links multiple environmental variables with the seasonality of new leaf production and old leaf litterfall. The new phenology simulates higher rates of leaf turnover (new leaves replacing old leaves) in dry seasons with more sunlight, which is then implemented in ORCHIDEE, together with recent findings of ontogeny‐associated photosynthetic capacity, and is evaluated against ground‐based measurements of leaf phenology (canopy leaf area index and litterfall), eddy‐covariance fluxes (photosynthesis and latent heat), and carbon allocations from field observations. Results show the periodical cycles of solar radiation and vapor pressure deficit are the two most important environmental variables that are empirically related to new leaf production and old leaf abscission in tropical evergreen forests. The model with new representation of leaf phenology captures the seasonality of canopy photosynthesis at three out of four sites, as well as the seasonality of litterfall, latent heat and light use efficiency of photosynthesis at all tested sites, and improves the seasonality of carbon allocations to leaves, roots and sapwoods. This study advances understanding of the environmental controls on tropical leaf phenology, and offers an improved modeling tool for gridded simulations of interannual CO2 and water fluxes in the tropics.
Xiuzhi Chen; Fabienne Maignan; Nicolas Viovy; Ana Bastos; Daniel Goll; Jin Wu; Liyang Liu; Chao Yue; Shushi Peng; Wenping Yuan; Adriana Castro da Conceição; Michael O'Sullivan; Philippe Ciais. Novel Representation of Leaf Phenology Improves Simulation of Amazonian Evergreen Forest Photosynthesis in a Land Surface Model. Journal of Advances in Modeling Earth Systems 2020, 12, 1 .
AMA StyleXiuzhi Chen, Fabienne Maignan, Nicolas Viovy, Ana Bastos, Daniel Goll, Jin Wu, Liyang Liu, Chao Yue, Shushi Peng, Wenping Yuan, Adriana Castro da Conceição, Michael O'Sullivan, Philippe Ciais. Novel Representation of Leaf Phenology Improves Simulation of Amazonian Evergreen Forest Photosynthesis in a Land Surface Model. Journal of Advances in Modeling Earth Systems. 2020; 12 (1):1.
Chicago/Turabian StyleXiuzhi Chen; Fabienne Maignan; Nicolas Viovy; Ana Bastos; Daniel Goll; Jin Wu; Liyang Liu; Chao Yue; Shushi Peng; Wenping Yuan; Adriana Castro da Conceição; Michael O'Sullivan; Philippe Ciais. 2020. "Novel Representation of Leaf Phenology Improves Simulation of Amazonian Evergreen Forest Photosynthesis in a Land Surface Model." Journal of Advances in Modeling Earth Systems 12, no. 1: 1.
Satellite observations show that leaf area index (LAI) has increased globally since 1981, but the impact of this vegetation structural change on the global terrestrial carbon cycle has not been systematically evaluated. Through process-based diagnostic ecosystem modeling, we find that the increase in LAI alone was responsible for 12.4% of the accumulated terrestrial carbon sink (95 ± 5 Pg C) from 1981 to 2016, whereas other drivers of CO2 fertilization, nitrogen deposition, and climate change (temperature, radiation, and precipitation) contributed to 47.0%, 1.1%, and −28.6% of the sink, respectively. The legacy effects of past changes in these drivers prior to 1981 are responsible for the remaining 65.5% of the accumulated sink from 1981 to 2016. These results refine the attribution of the land sink to the various drivers and would help constrain prognostic models that often have large uncertainties in simulating changes in vegetation and their impacts on the global carbon cycle.
Jing M. Chen; Weimin Ju; Philippe Ciais; Nicolas Viovy; Ronggao Liu; Yang Liu; Xuehe Lu. Vegetation structural change since 1981 significantly enhanced the terrestrial carbon sink. Nature Communications 2019, 10, 1 -7.
AMA StyleJing M. Chen, Weimin Ju, Philippe Ciais, Nicolas Viovy, Ronggao Liu, Yang Liu, Xuehe Lu. Vegetation structural change since 1981 significantly enhanced the terrestrial carbon sink. Nature Communications. 2019; 10 (1):1-7.
Chicago/Turabian StyleJing M. Chen; Weimin Ju; Philippe Ciais; Nicolas Viovy; Ronggao Liu; Yang Liu; Xuehe Lu. 2019. "Vegetation structural change since 1981 significantly enhanced the terrestrial carbon sink." Nature Communications 10, no. 1: 1-7.