References of "François, Louis"
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See detailGrowth of subtropical forests in Miocene Europe: The roles of carbon dioxide and Antarctic ice volume
Hamon, Noémie; Sépulchre, Pierre; Donnadieu, Yannick et al

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See detailDecrease in climatic conditions favouring floods in the south-east of Belgium over 1959-2010 using the regional climate model MAR
Wyard, Coraline ULg; Scholzen, Chloé ULg; Fettweis, Xavier ULg et al

in International Journal of Climatology (2017), 37(5), 27822796

The Ourthe River, in the south-east of Belgium, has a catchment area of 3,500 km2 and is one of the main tributaries of the Meuse River. In the Ourthe, most of the flood events occur during winter and ... [more ▼]

The Ourthe River, in the south-east of Belgium, has a catchment area of 3,500 km2 and is one of the main tributaries of the Meuse River. In the Ourthe, most of the flood events occur during winter and about 50% of them are due to heavy rainfall events combined to an abrupt melting of the snowpack covering the Ardennes massif during winter. This study aims to determine whether trends in extreme hydroclimatic events generating floods can be detected over the last century in Belgium, where a global warming signal can be observed. Hydroclimatic conditions favourable to floods were reconstructed over 1959- 2010 using the regional climate model MAR (“Modèle Atmosphérique Régional”) forced by the ERA-Interim/ERA-40, the ERA-20C and the NCEP/NCAR-v1 reanalyses. Extreme run-off events, which could potentially generate floods, were detected using run-off caused by precipitation events and snowpack melting from the MAR model. In the validation process, the MAR-driven temperature, precipitation and snow depth were successfully compared to daily weather data over the period 2008-2014 for 20 stations in Belgium. MAR also showed its ability to detect up to 90% of the hydroclimatic conditions which effectively generated observed floods in the Ourthe River over the period 1974- 2010. Conditions favourable to floods in the Ourthe River catchment present a negative trend over the period 1959-2010 as a result of a decrease in snow accumulation and a shortening of the snow season. This trend is expected to accelerate in a warmer climate. However, regarding the impact of the extreme precipitation events evolution on conditions favouring floods, the signal is less clear since the trends depend on the reanalysis used to force the MAR model. [less ▲]

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See detailBenchmarking carbon fluxes of the ISIMIP2a biome models
Chang, Jinfeng; Ciais, Philippe; Wang, Xuhui et al

in Environmental Research Letters (2017), 12

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See detailMiddle Miocene climate and vegetation models and their validation with proxy data
Henrot, Alexandra-Jane ULg; Utescher, Torsten; Erdei, Boglarka et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (2017), 467

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See detailReconstructing Cenozoic vegetation from proxy data and models – A NECLIME synthesis (Editorial)
François, Louis ULg; Bruch, A. A.; Utescher, T. et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (2017), 467

[No abstract available]

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See detailUsing a dynamic vegetation model for future projections of crop yields: simulations from the plot scale to the Belgian and European scales
Jacquemin, Ingrid ULg; Dury, Marie ULg; Henrot, Alexandra-Jane ULg et al

Conference (2016, September 29)

Dynamic vegetation models (DVM), such as CARAIB (“CARbon Assimilation In the Biosphere”) were initially designed to describe the dynamics of natural ecosystems as a function of climate and soil with the ... [more ▼]

Dynamic vegetation models (DVM), such as CARAIB (“CARbon Assimilation In the Biosphere”) were initially designed to describe the dynamics of natural ecosystems as a function of climate and soil with the aim of studying the role of vegetation in the carbon cycle. But their characteristics allow numerous other applications and improvements, such as the development of a crop module. This module can be validated at the plot scale, with the use of eddy-covariance data from agricultural sites in the FLUXNET network. The carbon fluxes (e.g., net ecosystem exchange (NEE), gross primary productivity (GPP)) and the evapotranspiration (ET) simulated with the CARAIB model are compared with the fluxes measured at several sites, in order to cover a maximum number of crop types (winter wheat/barley, sugar beets, potatoes, rapeseed,…) and to evaluate the model for different European regions (Belgium, France, Germany,…). The aim of this validation is to assess the model ability to reproduce the seasonal and inter-annual variability of carbon fluxes. In order to assess the spatial variability of the model, CARAIB will be applied over Belgium and forced with the outputs the regional climate model ALARO (4 km resolution), for the recent past and the decennial projections. To reach the larger scale, we also aim to assess crops yields over Europe and to quantify the uncertainties in the climatic projections. CARAIB will be driven with the outputs of different regional climatic models (RCMs), nested in CMIP5 GCM projections for the EURO-CORDEX project: ALADIN53 (Météo-France/CNRM), RACMO22E (KNMI), RCA4 (SMHI) and REMO2009 (MPI-CSC) RCMs. These climatic projections are at a high spatial resolution (0.11-degree, ≈12 km). The model will be set up for the most common crops in Europe and for simulations tests with marginal and/or new crops. Finally, this simulation ensemble will be used to highlight potential changes in the most productive areas of Europe. [less ▲]

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See detailAssessing the impact of climate change on terrestrial plants in Europe using a Dynamic Vegetation Model driven by EURO-CORDEX projections
Dury, Marie ULg; Hambuckers, Alain ULg; Henrot, Alexandra-Jane ULg et al

Poster (2016, September 26)

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more ... [more ▼]

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more long-term consequences on ecosystem composition, functioning and carbon storage. Hence, it is essential to assess the changes in climate variability and the changes in frequency of extreme events projected for the future. Here, the process-based dynamic vegetation model CARAIB DVM was used to evaluate and analyse how future climate and extreme events will affect European terrestrial plants. To quantify the uncertainties in climatic projections and their potential impacts on ecosystems, the vegetation model was driven with the outputs of different regional climatic models, nested in CMIP5 GCM projections for the EURO-CORDEX project: ALADIN53 (Météo-France/CNRM), RACMO22E (KNMI), RCA4 (SMHI) and REMO2009 (MPI-CSC) RCMs. These daily climatic scenarios are at a high spatial resolution (0.11°, ≈ 12 km). CARAIB simulations were performed across Europe over the historical period 1971-2005 and the future period 2006-2100 under RCP4.5 and RCP8.5 emission scenarios. We simulated a set of 99 individual species (47 herbs, 12 shrubs and 40 trees) representing the major European ecosystem flora. First, we analysed the climatic variability simulated by the climatic models over the historical period and compared it with the observed climatic variability. Then, we evaluated change in climatic variability and extreme events projected by the climatic models for the end of the century. Finally, we assessed the change in species productivity and abundance. We evaluated the severity of projected productivity change for the period 2070-2099 relative to their current productivity variability (period 1970-1999). Mean changes were considered severe if they exceed observed variability. The projections of potential shifts in species distributions are directly dedicated to current forest management. [less ▲]

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See detailResponse to droughts and heat waves of the productivity of natural and agricultural ecosystems in Europe within ISI-MIP2 historical simulations
François, Louis ULg; Henrot, Alexandra-Jane ULg; Dury, Marie ULg et al

Conference (2016, June 23)

According to the projections of climate models, extreme events such as droughts and heat waves are expected to become more frequent and more severe in the future. Such events are known to severely impact ... [more ▼]

According to the projections of climate models, extreme events such as droughts and heat waves are expected to become more frequent and more severe in the future. Such events are known to severely impact the productivity of both natural and agricultural ecosystems, and hence to affect ecosystem services such as crop yield and ecosystem carbon sequestration potential. Dynamic vegetation models are conventional tools to evaluate the productivity and carbon sequestration of ecosystems and their response to climate change. However, how far are these models able to correctly represent the sensitivity of ecosystems to droughts and heat waves? How do the responses of natural and agricultural ecosystems compare to each other, in terms of drought-induced changes in productivity and carbon sequestration? In this contribution, we use ISI-MIP2 model historical simulations from the biome sector. Eight dynamic vegetation models have participated in the biome sector intercomparison of ISI-MIP2: CARAIB, DLEM, JULES, LPJ-GUESS, LPJml, ORCHIDEE, VEGAS and VISIT. We focus the analysis on well-marked droughts or heat waves that occured in Europe after 1970, such as the 1976, 2003 and 2010 events. For most recent studied events, the model results are compared to the response observed at several eddy covariance sites in Europe, and, at a lager scale, to the drops in crop productivities reported in national statistics or to the drought impacts retrieved from satellite data (Terra MODIS instrument). [less ▲]

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See detailUsing a dynamic vegetation model for future projections of crop yields : application to Belgium in the framework of the VOTES and MASC projects
Jacquemin, Ingrid ULg; Henrot, Alexandra-Jane ULg; Fontaine, Corentin M. et al

Poster (2016, April 22)

Dynamic vegetation models (DVM) were initially designed to describe the dynamics of natural ecosystems as a function of climate and soil, to study the role of the vegetation in the carbon cycle. These ... [more ▼]

Dynamic vegetation models (DVM) were initially designed to describe the dynamics of natural ecosystems as a function of climate and soil, to study the role of the vegetation in the carbon cycle. These models are now directly coupled with climate models in order to evaluate feedbacks between vegetation and climate. But DVM characteristics allow numerous other applications, leading to amelioration of some of their modules (e.g., evaluating sensitivity of the hydrological module to land surface changes) and developments (e.g., coupling with other models like agent-based models), to be used in ecosystem management and land use planning studies. It is in this dynamic context about DVMs that we have adapted the CARAIB (CARbon Assimilation In the Biosphere) model. One of the main improvements is the implementation of a crop module, allowing the assessment of climate change impacts on crop yields. We try to validate this module at different scales: - from the plot level, with the use of eddy-covariance data from agricultural sites in the FLUXNET network, such as Lonzée (Belgium) or other Western European sites (Grignon, Dijkgraaf,. . . ), - to the country level, for which we compare the crop yield calculated by CARAIB to the crop yield statistics for Belgium and for different agricultural regions of the country. Another challenge for the CARAIB DVM was to deal with the landscape dynamics, which is not directly possible due to the lack of consideration of anthropogenic factors in the system. In the framework of the VOTES and the MASC projects, CARAIB is coupled with an agent-based model (ABM), representing the societal component of the system. This coupled module allows the use of climate and socio-economic scenarios, particularly interesting for studies which aim at ensuring a sustainable approach. This module has particularly been exploited in the VOTES project, where the objective was to provide a social, biophysical and economic assessment of the ecosystem services in four municipalities under urban pressure in the center of Belgium. The biophysical valuation was carried out with the coupled module, allowing a quantitative evaluation of key ecosystem services as a function of three climatic and socio-economic scenarios. [less ▲]

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See detailHigh-resolution climate and land surface interactions modeling over Belgium: current state and decennial scale projections
Jacquemin, Ingrid ULg; Henrot, Alexandra-Jane ULg; Beckers, Veronique et al

Poster (2016, April 21)

The interactions between land surface and climate are complex. Climate changes can affect ecosystem structure and functions, by altering photosynthesis and productivity or inducing thermal and hydric ... [more ▼]

The interactions between land surface and climate are complex. Climate changes can affect ecosystem structure and functions, by altering photosynthesis and productivity or inducing thermal and hydric stresses on plant species. These changes then impact socio-economic systems, through e.g., lower farming or forestry incomes. Ultimately, it can lead to permanent changes in land use structure, especially when associated with other non-climatic factors, such as urbanization pressure. These interactions and changes have feedbacks on the climate systems, in terms of changing: (1) surface properties (albedo, roughness, evapotranspiration, etc.) and (2) greenhouse gas emissions (mainly CO2, CH4, N2O). In the framework of the MASC project (« Modelling and Assessing Surface Change impacts on Belgian and Western European climate »), we aim at improving regional climate model projections at the decennial scale over Belgium and Western Europe by combining high-resolution models of climate, land surface dynamics and socio-economic processes. The land surface dynamics (LSD) module is composed of a dynamic vegetation model (CARAIB) calculating the productivity and growth of natural and managed vegetation, and an agent-based model (CRAFTY), determining the shifts in land use and land cover. This up-scaled LSD module is made consistent with the surface scheme of the regional climate model (RCM: ALARO) to allow simulations of the RCM with a fully dynamic land surface for the recent past and the period 2000-2030. In this contribution, we analyze the results of the first simulations performed with the CARAIB dynamic vegetation model over Belgium at a resolution of 1km. This analysis is performed at the species level, using a set of 17 species for natural vegetation (trees and grasses) and 10 crops, especially designed to represent the Belgian vegetation. The CARAIB model is forced with surface atmospheric variables derived from the monthly global CRU climatology or ALARO outputs (from a 4 km resolution simulation) for the recent past and the decennial projections. Evidently, these simulations lead to a first analysis of the impact of climate change on carbon stocks (e.g., biomass, soil carbon) and fluxes (e.g., gross and net primary productivities (GPP and NPP) and net ecosystem production (NEP)). The surface scheme is based on two land use/land cover databases, ECOPLAN for the Flemish region and, for the Walloon region, the COS-Wallonia database and the Belgian agricultural statistics for agricultural land. Land use and land cover are fixed through time (reference year: 2007) in these simulations, but a first attempt of coupling between CARAIB and CRAFTY will be made to establish dynamic land use change scenarios for the next decades. A simulation with variable land use would allow an analysis of land use change impacts not only on crop yields and the land carbon budget, but also on climate relevant parameters, such as surface albedo, roughness length and evapotranspiration towards a coupling with the RCM. [less ▲]

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See detailAssessing the Risk of Ecosystem Disruption in Europe using a Dynamic Vegetation Model driven by CMIP5 Regional Climatic Projections from EURO-CORDEX
Dury, Marie ULg; François, Louis ULg; Hambuckers, Alain ULg et al

Conference (2016, April 18)

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more ... [more ▼]

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more long-term consequences on ecosystem composition, functioning and carbon storage. Hence, it is essential to assess the changes in climate variability and the changes in frequency of extreme events projected for the future. Ecosystems could not be in a condition to adapt to these new conditions and might be disrupted. Here, the process-based dynamic vegetation model CARAIB DVM was used to evaluate and analyze how future climate and extreme events will affect European ecosystems. To quantify the uncertainties in the climatic projections and in their potential impacts on ecosystems, the vegetation model was driven with the outputs of different regional climatic models (RCMs), nested in CMIP5 GCM projections for the EURO-CORDEX project: ALADIN53 (Météo-France/CNRM), RACMO22E (KNMI), RCA4 (SMHI) and REMO2009 (MPI-CSC) RCMs. These climatic projections are at a high spatial resolution (0.11-degree, ≈ 12 km). CARAIB simulations were performed across Europe over the historical period 1951-2005 and the future period 2006-2100 under RCP4.5 and RCP8.5 emission scenarios. We simulated a set of 99 individual species (47 herbs, 12 shrubs and 40 trees) representing the major European ecosystem flora. First, we analyzed the climatic variability simulated by the climatic models over the historical period and compared it with the observed climatic variability. None of these climatic models can reproduce accurately the present natural climatic variability. Then, to assess the risk of ecosystem disruption in the future and to identify the vulnerable areas in Europe, we created an index combining several CARAIB outputs: runoff, mean NPP, soil turnover, burned area, appearance and disappearance of species. We evaluated the severity of change projected for these variables (period 2070-2099) relative to their current variability (period 1970-1999). Mean changes were considered severe if they exceed observed variability. The highest values of the index were found in southern Europe, indicating that the amplitude of the expected ecosystem changes largely exceeds current interannual variability in this area. This spatial risk index and the projections of potential shifts in species distributions are directly dedicated to current forest management to guide in planting or in assisted migration. [less ▲]

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See detailClassifying simulated wheat yield responses to changes in temperature and precipitation across a european transect
Fronzek, S.; Pirttioja, N.; Carter, T. R. et al

Conference (2016, March)

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See detailMiddle Miocene climate and vegetation models and their validation with proxy data
Henrot, Alexandra-Jane ULg; Utescher, T.; Erdei, B. et al

Report (2016)

The Miocene is a relatively recent epoch of the Earth's history with warmer climate than today, particularly during the middle Miocene Climatic Optimum (MMCO, approximately 17-15Ma). Although the cause of ... [more ▼]

The Miocene is a relatively recent epoch of the Earth's history with warmer climate than today, particularly during the middle Miocene Climatic Optimum (MMCO, approximately 17-15Ma). Although the cause of the warming is probably not only attributable to CO2, but also to changes in orography and configuration of ocean gateways, this time interval represents an ideal case study to test the ability of climate models to simulate warm climates comparable to those that the Earth may experience in the near future. However, even with higher than present-day CO2 concentrations, the MMCO warming inferred from terrestrial proxy data has been difficult to reproduce in climate models.Since fossil flora do not provide direct information on climate, but on flora and vegetation, climate model results are generally compared to climate reconstructions obtained from the fossil flora. In this study, we apply an alternative method by simulating palaeovegetation from the outputs of the climate model, using a dynamic vegetation model. Model vegetation reconstruction can then be compared to the vegetation cover indicated by the fossil flora record at the various localities, provided that a common classification of plant functional types (PFTs) is used for the data and the model. Here, we reconstruct the vegetation of the middle Miocene with the global dynamic vegetation model CARAIB, using the climatologies derived from five atmospheric general circulation models. The reliability of the simulations is examined on a presence/absence basis of PFTs by comparison of vegetation reconstructions to palaeoflora data recorded in the Northern Hemisphere and the Tropics.This comparison provides an overall agreement around 60% between model and data, when all sites and tree types are considered. Three model simulations out of five show to be better at predicting the absence than the presence. The presence of warm-temperate mixed forests in the middle latitudes, dominated by broadleaved deciduous warm temperate and subtropical trees is generally well reproduced in CARAIB simulations. However, poor agreement is obtained for the presence of tropical PFTs out of the Tropics and for warm PFTs at latitudes northward of 50°N, where climate models remain too cold to produce assemblages of trees consistent with the data. Nevertheless, the model-data comparison performed here highlights several mismatches that could result not only from missing feedbacks in the climate simulations, but also from the data. The results of the likelihood analysis on presence/absence of PFTs illustrate the uncertainties in the PFT classification of the Neogene floral records. The coexistence of some PFTs in the palaeovegetation data is impossible to reproduce in the vegetation model simulations because of the climatic definition of the modern PFTs. This result indicates either a bias in the identification of modern analogues for fossil plant taxa, or a possible evolution of environmental requirements of certain plants. © 2016 Elsevier B.V. [less ▲]

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See detailAssessing the Risk of Ecosystem Disruption in Europe using a Dynamic Vegetation Model driven by CMIP5 Regional Climatic Projections from EURO-CORDEX
Dury, Marie ULg; Hambuckers, Alain ULg; Henrot, Alexandra-Jane ULg et al

Conference (2015, December 18)

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more ... [more ▼]

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more long-term consequences on ecosystem composition, functioning and carbon storage. Hence, it is essential to assess the changes in climatic variability and the changes in frequency of extreme events projected for the future. Ecosystems could not be in a condition to adapt to these new conditions and might be disrupted. Here, the process-based dynamic vegetation model CARAIB DVM was used to evaluate and analyze how future climate and extreme events will affect European ecosystems. To quantify the uncertainties in the climatic projections and in their potential impacts on ecosystems, the vegetation model was driven with the outputs of different regional climatic models (RCMs), nested in CMIP5 GCM projections for the EURO-CORDEX project. We used the ALADIN version 5.3 (Météo-France/CNRM) and other EURO-CORDEX RCMs. These climatic projections are at a high spatial resolution (0.11-degree, ~12 km). CARAIB simulations were performed across Europe over the historical period 1951-2005 and the future period 2006-2100 under RCP4.5 and RCP8.5 emission scenarios. We simulated a set of 99 individual species (47 herbs, 12 shrubs and 40 trees) representing the major European ecosystem flora. First, we analyzed the climatic variability simulated by the climatic models over the historical period and compared it with the observed climatic variability. None of these climatic models can reproduce accurately the present natural climatic variability. Then, to assess the risk of ecosystem disruption in the future and to identify the vulnerable areas in Europe, we created an index combining several CARAIB outputs: runoff, mean NPP, soil turnover, burned area, appearance and disappearance of species. We evaluated the severity of change projected for these variables (period 2071-2100) relative to their current variability (period 1961-1990). Mean changes were considered severe if they exceed observed variability. The highest values of the index were found in southern Europe, indicating that the amplitude of the expected ecosystem changes largely exceeds current interannual variability in this area. [less ▲]

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See detailModeling Pacific Northwest carbon and water cycling using CARAIB Dynamic Vegetation Model
Kim, John B; Dury, Marie ULg; Still, Christopher J et al

Poster (2015, December 14)

While uncertainties remain regarding projected temperature and precipitation changes, climate warming is already affecting ecosystems in the Pacific Northwest (PNW). Decrease in ecosystem productivity as ... [more ▼]

While uncertainties remain regarding projected temperature and precipitation changes, climate warming is already affecting ecosystems in the Pacific Northwest (PNW). Decrease in ecosystem productivity as well as increase in mortality of some plant species induced by drought and disturbance have been reported. Here, we applied the process-based dynamic vegetation model CARAIB to PNW to simulate the response of water and carbon cycling to current and future climate change projections. The vegetation model has already been successfully applied to Europe to simulate plant physiological response to climate change. We calibrated CARAIB to PNW using global Plant Functional Types. For calibration, the model is driven with the gridded surface meteorological dataset UIdaho MACA METDATA with 1/24-degree (~4-km) resolution at a daily time step for the period 1979-2014. The model ability to reproduce the current spatial and temporal variations of carbon stocks and fluxes was evaluated using a variety of available datasets, including eddy covariance and satellite observations. We focused particularly on past severe drought and fire episodes. Then, we simulated future conditions using the UIdaho MACAv2-METDATA dataset, which includes downscaled CMIP5 projections from 28 GCMs for RCP4.5 and RCP8.5. We evaluated the future ecosystem carbon balance resulting from changes in drought frequency as well as in fire risk. We also simulated future productivity and drought-induced mortality of several key PNW tree species. [less ▲]

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See detailAnalysing the response of European ecosystems to droughts and heat waves within ISI-MIP2 simulations
Henrot, Alexandra-Jane ULg; Dury, Marie ULg; François, Louis ULg et al

Conference (2015, December 14)

With unprecedented speed and extent, the future climate change can be expected to severely impact terrestrial ecosystems due to more frequent extreme events, such as droughts or heat waves. What will be ... [more ▼]

With unprecedented speed and extent, the future climate change can be expected to severely impact terrestrial ecosystems due to more frequent extreme events, such as droughts or heat waves. What will be the impacts of these extreme events on ecosystem functioning and structure? How far will net primary production be reduced by such events? What will be the impact on plant mortality? Could such events trigger changes in the abundance of plant species, thus leading to biome shifts? In this contribution, we propose to use ISI-MIP2 model historical simulations from the biome sector to analyse the response of ecosystems to droughts or heat waves, trying to understand the differences between several vegetation models (e.g. CARAIB, HYBRID, LPJ). The analysis will focus on Europe. It will compare and assess the model responses for a series of well-marked drought or heat wave events in the simulated historical period, such as those that occurred in 1976, 2003 or 2010. This analysis will be performed in terms of several important environmental variables, like soil water and hydric stress, runoff, PFT abundance, net primary productivity and biomass, fire frequency, turnover of soil organic matter, etc. Whenever possible, the response of the model will be compared to available data for the most recent well-marked events. Examples of data to be used are eddy covariance, satellite data (including leaf area and fire occurrence) or tree rings. [less ▲]

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See detailToward modeling Pacific Northwest tree species using CARAIB dynamic vegetation model
Dury, Marie ULg; Still, Christopher J; Kim, John B et al

Poster (2015, November 04)

While uncertainties remain regarding projected temperature and precipitation changes, climate warming is already affecting Pacific Northwest (PNW) ecosystems, notably forest species composition. In this ... [more ▼]

While uncertainties remain regarding projected temperature and precipitation changes, climate warming is already affecting Pacific Northwest (PNW) ecosystems, notably forest species composition. In this research, we use the process-based dynamic vegetation model CARAIB DVM (Dury et al., iForest - Biogeosciences and Forestry, 4:82-99, 2011) to simulate current distribution of common tree species in PNW ecosystems. This DVM includes the influence of soil water content, atmospheric CO2 concentration and disturbances like fires, all essential to consider for reliably predicting present and future plant species distributions. Classically, dynamic vegetation models represent vegetation at the scale of plant functional types (PFTs). However, since they have a narrower bioclimatic spectrum, individual species are probably more vulnerable to climate change than PFTs. Here, we first perform simulations with the CARAIB global vegetation classification based on 26 Plant Functional Types (3 herbaceous, 8 shrubby and 15 arboreal PFTs). Then, we apply the vegetation model at the species level in order to analyse the response of a selected set of plant species to current climate. Representing the European vegetation at the scale of individual species has been successfully performed with CARAIB. The simulated individual species are differentiated by their proper climatic requirements and tolerances. Concerning physiological and structural parameters, species share the traits of the respective PFT, but we progressively improve their characterization by the use of global or local trait databases (e.g., TRY database). The model is driven with climatic observation data over the period 1951-2012 across the PNW region at different spatial resolutions. We test the model’s ability to reproduce the present spatial and temporal variations of carbon stocks and fluxes as well as the observed species and biome distributions over the PNW. We then assess model predictions using a variety of available datasets, including eddy covariance and satellite observations. [less ▲]

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See detailComment l'agriculture peut-elle contribuer à limiter les changements climatiques? Contribution de la recherche.
Heinesch, Bernard ULg; Aubinet, Marc ULg; Dehareng, Frédéric et al

Conference given outside the academic context (2015)

Detailed reference viewed: 21 (3 ULg)