Publications of Marie Dury
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See detailSimulating the Holocene re-colonization of Europe by tree species using dynamic vegetation models
Dury, Marie ULiege; Lehsten, Dörte; Dullinger, Stefan et al

Poster (2011, April)

At the beginning of the Holocene (10.000 BP) started a progressive re-colonization of Europe by temperate tree species from a limited number of glacial refugia. To reconstruct the speed, seemingly species ... [more ▼]

At the beginning of the Holocene (10.000 BP) started a progressive re-colonization of Europe by temperate tree species from a limited number of glacial refugia. To reconstruct the speed, seemingly species-specific, and the routes of the postglacial spread of European tree species, fossil records collected from various localities in Europe are invaluable. However, the relative roles of climatic fluctuations, dispersal capacities of individual species, and inter-specific competition in controlling the re-colonization rates remain controversial. We investigate these different aspects with two dynamic vegetation models (DVM), LPJ-GUESS and CARAIB. Transient runs of both models were performed over the Holocene, using HadCM3 GCM-reconstructed climate. Large-scale species migration at 0.5◦ x0.5◦ is represented in these models using migration rates derived from a small-scale cellular automaton, CATS. Individual tree species migration rates were pre-calculated with CATS every 1000 years over each grid cell used by the DVMs in the climatic conditions reconstructed by the GCM. In the DVMs, these migration speeds were influenced by the response to competition from other species, expressed as a function of net primary production ratios. The DVMs were used to study the migration of one species, from its 10.000 BP refugia, within a landscape defined by a set of other species for which no dispersal limitations are assumed. Here, we illustrate the results obtained for wind-dispersed tree species and compare them to their past distributions reconstructed from pollen and macrofossil data. [less ▲]

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See detailModelling Climate and Vegetation Interactions at the Middle Miocene with the Planet Simulator and CARAIB
Henrot, A.-J.; Munhoven, Guy ULiege; François, Louis ULiege et al

Conference (2011, January 18)

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See detailResponses of European forest ecosystems to 21(st) century climate: assessing changes in interannual variability and fire intensity
Dury, Marie ULiege; Hambuckers, Alain ULiege; Warnant, P. et al

in iForest: Biogeosciences and Forestry (2011), 4

Significant climatic changes are currently observed and, according to projections, will be strengthened over the 21(st) century throughout the world with the continuing increase of the atmospheric CO2 ... [more ▼]

Significant climatic changes are currently observed and, according to projections, will be strengthened over the 21(st) century throughout the world with the continuing increase of the atmospheric CO2 concentration. Climate will be generally warmer with notably changes in the seasonality and in the precipitation regime. These changes will have major impacts on the biodiversity and the functioning of natural ecosystems. The CARAIB dynamic vegetation model driven by the ARPEGE/Climate model under forcing from the A2 IPCC emission scenario is used to illustrate and analyse the potential impacts of climate change on forest productivity and distribution as well as fire intensity over Europe. The potential CO2 fertilizing effect is studied throughout transient runs of the vegetation model over the 1961-2100 period assuming constant and increasing atmospheric CO2 concentration. Without fertilisation effect, the net primary productivity (NPP) might increase in high latitudes and altitudes (by up to 40 % or even 60-100 %) while it might decrease in temperate (by up to 50 %) and in warmer regions, e.g., Mediterranean area (by up to 80 %). This strong decrease in NPP is associated with recurrent drought events occurring mostly in summer time. Under rising CO2 concentration, NPP increases all over Europe by as much as 25-75%, but it is not clear whether or not soils might sustain such an increase. The model indicates also that interannual NPP variability might strongly increase in the areas which will undergo recurrent water stress in the future. During the years exhibiting summer drought, the NPP might decrease to values much lower than present-day average NPP even when CO2 fertilization is included. Moreover, years with such events will happen much more frequently than today. Regions with more severe droughts might also be affected by an increase of wildfire frequency and intensity, which may have large impacts on vegetation density and distribution. For instance, in the Mediterranean basin, the area burned by wildfire can be expected to increase by a factor of 3-5 at the end of the 21(st) century compared to present. [less ▲]

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See detailResponse of the European forests to extreme climatic events predicted for the 21st century: sensitivity to climate models and their variability
Dury, Marie ULiege; Hambuckers, Alain ULiege; Warnant, Pierre et al

Conference (2010, October)

Significant climatic changes are currently observed and, according to projections, will be strengthened over the 21st century throughout the world with the enhanced greenhouse effect. Climate will be ... [more ▼]

Significant climatic changes are currently observed and, according to projections, will be strengthened over the 21st century throughout the world with the enhanced greenhouse effect. Climate will be generally warmer with notably changes in the seasonality and in the precipitation regime. The CARAIB dynamic vegetation model is used to evaluate and analyse the potential impacts of climate change on forests ecosystems in Europe. Changes in the hydrological budget as well as in the intensity and the frequency of wildfires and their effects on forest productivity and distribution are especially assessed. CARAIB is driven by the ARPEGE-Climat model and some other regional climate models from the European Union (EU) project ENSEMBLES forced with IPCC A1B emission scenario. Climate projections indicate changes in variability and frequency of extreme events. Since climate variability governs the response of plant species (e.g. net primary productivity, NPP) to climate change, we analyse the climate variability (seasonal and interannual) given by climate models comparing it with the observed climate variability (CRU TS 3.0 historical climate dataset) over the period 1961-1990. The variability modelled by the ARPEGE-Climat model is notably slightly more pronounced than the observed one, at least for some areas. Since discrepancies between modelled and observed current climate variability may affect NPP variability calculated for the future as well as the intensity and the frequency of severe drought period and wildfires, comparing the forest ecosystem evolutions obtained with a range of climate models allows improving the assessment of climate change impacts on forest in the future. [less ▲]

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See detailResponse of the European ecosystems to climate change: a modelling approach for the 21st century
Dury, Marie ULiege; Warnant, Pierre; François, Louis ULiege et al

Poster (2010, May)

According to projections, over the 21st century, significant climatic changes appear and will be strengthened all over the world with the continuing increase of the atmospheric CO2 level. Climate will be ... [more ▼]

According to projections, over the 21st century, significant climatic changes appear and will be strengthened all over the world with the continuing increase of the atmospheric CO2 level. Climate will be generally warmer with notably changes in the seasonality and in the precipitation regime. These changes will have major impacts on the environment and on the biodiversity of natural ecosystems. Geographic distribution of ecosystems may be modified since species will be driven to migrate towards more suitable areas (e. g., shifting of the arctic trees lines). The CARAIB dynamic vegetation model (Carbon Assimilation in the Biosphere) forced with 21st century climate scenarios of the IPCC (ARPEGE-Climat model) is used to illustrate and analyse the potential impacts of climate change on tree species distribution and productivity over Europe. Changes in hydrological budget (e. g., runoff) and fire effects on forests will also be shown. Transient runs (1975-2100) with a new dynamic module introduced in CARAIB are performed to follow the future evolutions. In the new module, the processes of species establishment, competition and mortality due to stresses and disturbances have been improved. Among others, increased atmospheric CO2 and warmer climate increase tree productivity while drier conditions decrease it. Regions with more severe droughts will also be affected by an increase of wildfire frequency, which may have large impacts on vegetation density and distribution. [less ▲]

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See detailResponse of the European ecosystems to climate change: a modeling approach for the 21st century
Dury, Marie ULiege; Warnant, Pierre; François, Louis ULiege et al

Poster (2010, April)

Detailed reference viewed: 11 (1 ULiège)
See detailEuropean vegetation evolution during the Holocene simulated by Planet Simulator and CARAIB
Haberkorn, K.; Fraedrich, K.; Henrot, Alexandra-Jane ULiege et al

Poster (2010, April)

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See detailImpacts of Climate Change on Tropical and Subtropical Ecosystems
François, Louis ULiege; Favre, E.; Henrot, Alexandra-Jane ULiege et al

Conference (2009, June)

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See detailEstimation de la transparence de l'atmosphère par ciel clair à la Station Scientifique des Hautes-fagnes (SSHF), Mont Rigi, Belgique. Comparaison avec la Station d'Uccle-Bruxelles (IRM)
Dury, Marie ULiege; Ginion, Serge; Erpicum, Michel ULiege

in Bulletin de la Société Géographique de Liège (2009), 51(2008), 5-16

This paper deals with the study of the transparency of the atmosphere on clear sky at the Mont Rigi (Belgian Hautes-Fagnes) with the aim of underlining the particularities of the air composition in the ... [more ▼]

This paper deals with the study of the transparency of the atmosphere on clear sky at the Mont Rigi (Belgian Hautes-Fagnes) with the aim of underlining the particularities of the air composition in the Hautes-Fagnes region and quantifying its influence on global solar radiation. We used the following data: solar elevation, water vapor content (characterized by atmospheric water depth) and solar extraterrestrial irradiation at the top of the atmosphere. Due to a lack of direct information about atmospheric pollution, we compared global radiation received at the Hautes-Fagnes scientific station (SSHF) on clear sky with that stored in the same conditions in Uccle (Brussels), the Belgian reference station (Royal meteorological institute, RMI) and urban area. [less ▲]

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See detailProjections à l’échéance 2100 des changements de température et de précipitations en Belgique réalisées à l’aide des modèles du GIEC
Dury, Marie ULiege

Master's dissertation (2008)

En 2007, le Groupe d’experts du GIEC a publié son 4e rapport (AR4) sur les changements climatiques. Les résultats proposés dans l’AR4 ont été obtenus à l’aide d’un vaste échantillon de modèles de ... [more ▼]

En 2007, le Groupe d’experts du GIEC a publié son 4e rapport (AR4) sur les changements climatiques. Les résultats proposés dans l’AR4 ont été obtenus à l’aide d’un vaste échantillon de modèles de circulation générale (AOGCMs) nouvellement homologués par le groupe. Notre travail a profité des avancées réalisées dans le monde de la modélisation climatique pour tenter de procéder à un état des lieux, remise à jour améliorée, des changements climatiques qui pourraient être enregistrés en Belgique au cours du 21e siècle en matière de température et de précipitations. Etant donné le large éventail de modèles mis à notre disposition, nous avons pu nous permettre d’écrémer ce vaste catalogue, ce que d’autres travaux antérieurs n’avaient pu faire. Ainsi, la première partie de cette étude est-elle consacrée à l’évaluation des différents AOGCMs dans le but de ne conserver que les plus aptes à réaliser des projections climatiques cohérentes pour notre territoire. La seconde partie de notre travail porte sur l’analyse des projections réalisées pour la Belgique par les huit modèles de circulation générale sélectionnés dans la partie précédente. Pour resituer les changements climatiques que les AOGCMs annoncent pour notre pays dans un contexte régional plus large, nous décrivons préalablement l’évolution climatique que connaîtra l’Europe au 21e siècle. Pour la Belgique, nous nous attachons à montrer les évolutions dans les moyennes annuelles et saisonnières pour les températures moyenne, minimale et maximale ainsi que pour les précipitations. Ensuite, nous tentons d’identifier les changements dans les statistiques journalières des évènements « extrêmes », ce qui, il faut le souligner, n’avait encore jamais été réalisé pour notre territoire. Ainsi, les évolutions dans le nombre de jours de gel, de jours de canicule, de vagues de chaleur,… et les changements dans la distribution des intensités des précipitations journalières ont été étudiés. [less ▲]

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See detailContribution à l’étude du rayonnement solaire à la station météorologique du Mont Rigi. Transparence de l’atmosphère et albédo
Dury, Marie ULiege

Master's dissertation (2006)

Notre mémoire s’est centré sur le rayonnement solaire au Mont Rigi à partir de la grande quantité de paramètres météorologiques engrangés par la nouvelle station météorologique automatique de l’I.R.M ... [more ▼]

Notre mémoire s’est centré sur le rayonnement solaire au Mont Rigi à partir de la grande quantité de paramètres météorologiques engrangés par la nouvelle station météorologique automatique de l’I.R.M. (2001). Jusqu’à ce jour, aucune étude systématique n’avait encore été consacrée à ce beau sujet. Dans la première partie, nous présentons la station et les appareils de mesure en étant surtout soucieuse d’évoquer et d’illustrer les perturbations dont peuvent souffrir les mesures suite aux conditions météorologiques parfois rudes dans les Hautes-Fagnes telles qu’on n’en rencontre pas dans les autres stations automatiques du pays et qui ne sont pas toujours compatibles avec des enregistrements automatiques. La deuxième partie, point central de notre travail, porte sur l’étude de la transparence de l’atmosphère au Mont Rigi avec pour objectif de mettre en évidence les particularités de la composition de l’air de la région et de quantifier son influence sur le rayonnement solaire. Nous avons utilisé les paramètres à notre disposition: la hauteur du soleil, la teneur en vapeur d’eau de l’air (caractérisée par la hauteur d’eau condensable) et la couverture nuageuse. La troisième partie s’intéresse à la variation de l’albédo de la surface sous le pyranomètre, caractérisée par une végétation herbacée et hétérogène, composée d’espèces courantes dans les Hautes-Fagnes (épilobes en épis, myrtille, callune,…). Cette question n'a pas constitué le point central de notre recherche mais étant donné que nous possédions deux ans et demi de mesures en continu d’albédo, il était intéressant d’apporter de nouvelles observations à l’étude de ce paramètre. [less ▲]

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