Modeling Russia for Climate Change Issues

This paper presents the dynamic multi-sector general equilibrium model for the Russian Federation (RusMod) and carbon emission projections for Russia up to 2020.Projection results emphasise the importance of accomplishing strong energy efficiency gains, and their effect on the economy and on emissions of greenhouse gases. However, they also show that emissions can be expected to grow at a much higher rate if the efficiency improvements targeted by the government are not realised or when they stay behind compared to the 40% goal as it was set by president Medvedev. Model simulations also show that the introduction of a carbon price as a policy instrument can have a strong impact on the emissions, which comes at the expense of a decline in economic growth that is of a much more temporary nature.

Rétention des produits phytosanitaires dans les fossés de connexion parcelle-cours d'eau

Pour lutter contre les pollutions diffuses en milieu rural, de nombreux programmes d'action se mettent en place. Le développement de recherches sur les connexions parcelle - cours d'eau devrait permettre de mieux comprendre le transfert et la dissipation des polluants dans ce milieu. En particulier, les fossés, structures relativement fréquentes dans les territoires cultivés, peuvent, a priori, avoir une fonction de court-circuit et donc faciliter le transfert des produits phytosanitaires, ou au contraire constituer des éléments de pondération de la pollution. Afin d'éclaircir ce point, une première série d'expérimentations a été menée par le Cemagref (Institut français de recherche pour l'ingénierie de l'agriculture et de l'environnement) dans des fossés de drainage agricole. Une solution aqueuse contenant trois herbicides aux caractéristiques physico-chimiques différentes (isoproturon, diuron et diflufénicanil), et un traceur (chlorures) a été injectée pendant quelques minutes dans quatre fossés. Des échantillons d'eau ont été prélevés à pas de temps fins à deux emplacements en aval du point d'injection. Après dosage par chromatographie au laboratoire, les résultats indiquent une diminution du flux et de la concentration maximale du pic de polluants comparativement à un traceur. En outre, la variation observée est corrélée aux propriétés physico-chimiques des produits, en particulier au coefficient de partage Koc. L'étude présentée montre que la surface de contact (liée à la nature du substrat) et le temps de contact (dépendant essentiellement des conditions d'écoulement) entre les polluants et le substrat sont les paramètres qui influent majoritairement sur la dissipation des produits phytosanitaires.The use of pesticide may lead to the contamination of surface and groundwaters. Agricultural nonpoint source pollution originates from land areas which intermittently contribute to the compound transfer to water. Several studies report on the occurrence of pesticides in surface water resources, with concentrations over the limit set by the 80/778 EEC directive for drinking water (0.1 µg/L for each substance and 0.5 µg/L for all pesticides). Numerous herbicides of different chemical families are detected in surface waters, especially triazines and ureas. Their concentrations vary with time and space partly in relation with application patterns and pluviometry. Maximum concentrations are linked to runoff, originating from agricultural fields and primarily occur right after the application periods.Many methods and levels of actions can be used to reduce water pollution. First, better agricultural practices can be set up, such as choosing the best dose and application period, controlling toxic substance impacts, combining with non-chemical practices. However, pesticide losses from fields can't be totally cancelled because of the complexity of the involved parameters (agricultural practices, climatic conditions, soil physical, chemical and biological properties …). In fact drift during application, runoff or drainage systems may still occur and have an effect on water quality. It may be then pertinent to evaluate to which extent the non treated areas between the fields and the surface water bodies can dissipate pesticide concentrations before they reach them. Pesticides leaving a plot in surface runoff may pass through various landscape components before reaching rivers ; including another field, a ditch, a small brook, a vegetative buffer zone. Besides, pesticide leaving the plot through drainage straightly moves agricultural ditches or streams. However, the contribution of each of these elements in pesticide dissipation is not well known, except for buffer zones (grassed or forest strips) (PATTY (1997). Cemagref (a French research institute), CEH Wallingford and ITCF (Institut Technique des Cereales et des Fourrages) attempt to extend their study to the other elements as agricultural ditches.This paper deals with the role of farm ditches and small streams in the transport and retention of pesticides from fields to the main river network. Their presence seems to play a significant role in the transfer of nonpoint source pollution (especially in the West of France). Indeed they can either accelerate pesticide transport or reduce it, according to their characteristics (length, flow, bottom sediment or soil characteristics, plants and organic matter contents, etc.). Since 1998, Cemagref has been investigating the retention of pesticides by several natural ditches with varied flows and substratum. A water solution containing three herbicides with different physico chemical properties (diflufenican, diuron and isoproturon) and potassium chloride, a tracer, is introduced with a pump in each ditch for about five minutes with a constant concentration. Water samples are collected in the ditches every two or five minutes at two distances from the injection point. The samples are stored in amber polyethylene terephtalate bottles and frozen. Laboratory analysis is performed by liquid-liquid extraction with dichloromethane and then liquid or gas chromatography depending on the compounds.The analysis of the water samples highlights a reduction of the maximum concentration and of the accumulative mass of each pesticide with distance compared to the tracer. Indeed, even if all the chloride ions used as tracers are not recovered at each sampling point (due to infiltration or lateral losses), we notice more significant losses for all the studied herbicides. The reduction can reach 70 % of the applied mass for diflufenican compared to the tracer. The retention of pesticides is also linked to their own physical and chemical properties. Thus, diflufenican, which has the highest sorption coefficient value, Koc, is also the most retained pesticide, whereas the total injected mass of isoproturon is recovered in most cases. Diuron has an intermediate behaviour.In brief, this field experiment proves that the surface and time of contact between pollutants and substratum are likely to play a major role in pesticide retention. An estimated adsorption capacity of each ditch has been assessed, which is based on laboratory sorption experiments on different natural substratum. Despite the few data, a relationship between diflufenican retention in ditches and the estimated adsorption capacity of each ditch has been underscored.This study also highlighted major limits of field experiments. For example, accurate flow measurements are really difficult to carry out with simple methods for low values. The conventional techniques can't be used with small water height or in ditch where the bottom is filled with plants or grass. Chloride ion was chosen in this study because it is easy to analyze, but the results showed an initial presence of chloride ion in the natural ditch water which incites to replace it by another tracer such as bromide with is not found in the environment in future field experiments.For all these reasons, some pilot experiments with a physical model (an artificial ditch of 8 m long and 0.4 m wide) are now designed. This equipment allows to adjust and control hydrodynamic parameters such as water flow, water height, and the nature and structure of the substratum. Then, it is possible to quantify both the role played by the substratum, mainly the organic matter content, and the role of the contact time. These parameters could be then taken into account in order to optimize further experiments on adsorption. The primary tests without substratum already give references for hydrodynamic measurements, as the stability of the water flow and the homogeneity of the initial solution concentration

Application de la méthode LSPIV pour la mesure de champs de vitesse et de débits de crue sur modèle réduit et en rivière

International audienceLSPIV technique enables the measurement of surface flow velocities using image sequence analysis. EDF and Irstea partnership made possible the development of Fudaa‑LSPIV freeware by DeltaCAD Company. Two software applications at flume and field scales are detailed: (i) bed shear stresses were calculated owing to LSPIV velocities, water depth and bathymetry for a physical model of the Old Rhine; (ii) the software was used to optimize the calculation parameters of LSPIV flood discharge measurement stations in Mediterranean rivers.La technique LSPIV (Large Scale Particle Image Velocimetry) permet de mesurer les vitesses de surface d'un écoulement par analyse de séquence d'images. Pour faciliter l'application opérationnelle de la méthode, un logiciel, Fudaa-LSPIV, a été développé par la société DeltaCAD dans le cadre d'une collaboration entre EDF et Irstea. Deux applications en laboratoire et en rivière sont présentées : (i) couplée avec des mesures de hauteur d'eau et de bathymétries, la LSPIV a permis d'estimer des paramètres de Shields sur le modèle physique à fond mobile du Vieux-Rhin ; (ii) le logiciel a été utilisé pour procéder à des analyses de sensibilité pour paramétrer ainsi au mieux les stations LSPIV de mesure de débit en crue de rivières cévenoles

Morphodynamics of the exit of a cutoff meander: experimental findings from field and laboratory studies

The morphological evolution of the entrances and exits of abandoned river channels governs their hydrological connectivity. The study focusses on flow and sediment dynamics in the exit of a cut-off meander where the downstream entrance is still connected to the main channel, but the upstream entrance is closed. Two similar field and laboratory cases were investigated using innovative velocimetry techniques (acoustic Doppler profiling, image analysis). Laboratory experiments were conducted with a mobile-bed physical model of the Morava river (Slovakia). Field measurements were performed in the exit of the Port-Galland cut-off meander, Ain river (France). Both cases yielded consistent and complementary results from which a generic scheme for flow patterns and morphological evolution was derived. A simple analogy with flows in rectangular side cavities was used to explain the recirculating flow patterns which developed in the exit. A decelerating inflow deposits bedload in the downstream part of the cavity, while the upstream part is eroded by an accelerating outflow, leading to the retreat of the upstream bank. In the field, strong secondary currents were observed, especially in the inflow, which may enhance the scouring of the downstream corner of the cavity. Also, fine sediment deposits constituted a silt layer in a transitional zone, located between the mouth of the abandoned channel and the oxbow-lake within the cut-off meander. Attempts at morphological prediction should consider not only the flow and sediment conditions in the cavity, but also the dynamics of the main channel

Emploi des profileurs acoustiques à effet Doppler (aDcp) pour étudier la structure des écoulements en rivière

Depuis une quinzaine d'années, les profileurs de vitesse acoustiques à effet Doppler (aDcp) sont de plus en plus employés par les équipes hydrométriques pour le jaugeage des cours d'eau. Ces appareils offrent la possibilité d'investiguer la bathymétrie et les vitesses d'écoulement tridimensionnelles rapidement, de manière peu intrusive, sur de vastes domaines et pour une large gamme de conditions de terrain. Le principe de fonctionnement, les stratégies de déploiement et de traitement des données mises en oeuvre sont exposés en s'appuyant sur un cas d'étude expérimental: la station hydrométrique "Saint-Georges" sur la Saône à Lyon

Quantifier l'effet de choix du site dans l'incertitude des jaugeages ADCP par transects

HMEM, Durham, New Hampshire, USA, 09-/07/2017 - 12/07/2017International audienceStage-discharge rating curves are used to relate streamflow discharge to continuously measured river stage readings to create a continuous record of streamflow discharge. The stage-discharge relationship is estimated and refined using discrete streamflow measurements over time, during which both the discharge and stage are measured. There is uncertainty in the resulting rating curve due to multiple factors including the curve-fitting process, assumptions on the form of the model used, fluvial geomorphology of natural channels, and the approaches used to extrapolate the rating equation beyond available observations. This rating curve uncertainty leads to uncertainty in the streamflow timeseries, and therefore to uncertainty in predictive models that use the streamflow data. Many different methods have been proposed in the literature for estimating rating curve uncertainty, differing in mathematical rigor, in the assumptions made about the component errors, and in the information required to implement the method at any given site. This study describes the results of an international experiment to test and compare streamflow uncertainty estimation methods from 7 research groups across 9 institutions. The methods range from simple LOWESS fits to more complicated Bayesian methods that consider hydraulic principles directly. We evaluate these different methods when applied to three diverse gauging stations using standardized information (channel characteristics, hydrographs, and streamflow measurements). Our results quantify the resultant spread of the stage-discharge Quantifying the uncertainty of discharge measurements (or "gaugings") is a challenge in the hydrometric community. A useful tool to empirically estimate the uncertainty of a gauging method is the field inter-laboratory experiment (Le Coz et al., 2016). Previous inter-laboratory experiments conducted in France (in 2009, 2010, 2011 and 2012) showed that the expanded uncertainty (with a probability level of 95%) of an ADCP gauging made of six successive transects is typically around 5% under optimum site conditions (straight reach, uniform and smooth streambed cross-section, homogeneous flow, etc.) and may be twice higher under poorer site conditions. In practice, the selected cross-section does not always match all quality requirements which may result in larger uncertainty. However, the uncertainty due to site selection is very difficult to estimate with predictive equations. From 9 to 10 November 2016, 50 teams from 8 different countries, using 50 ADCPs simultaneously, conducted more than 600 discharge measurements in steady flow conditions (~14 m3/s released by a dam). 26 cross-sections with various shapes and flow conditions were distributed over 500 meters along the Taurion River at Saint-Priest-de-Taurion, France. A specific experiment protocol, which consisted of circulating every team over half of the cross-sections, was implemented in order to quantify the impact of site selection on the discharge measurement uncertainty. Beyond the description of the experiments, uncertainty estimates are presented. The overall expanded uncertainty of a 6-transect ADCP gaugings (duration around 720 seconds) is estimated to be around 6%.The uncertainty of the discharge measurements varies among the cross-sections. These variations are well correlated to the expert judgment on the cross-section quality made by each team. First results seem to highlight a relation between uncertainty computed for each cross-section and criteria such as flow shallowness and measured discharge ratio. Further investigations are necessary to identify the criteria related to error sources that are possibly meaningful for categorizing measurement conditions and site selection. Moreover, experimental uncertainty and the uncertainty predicted by analytical methods such as QRev, QUant, OURSIN, RiverFlowUA or QMSys software will be compared

The AVuPUR project (Assessing the Vulnerabiliy of Peri-Urbans Rivers): experimental set up, modelling strategy and first results

International audienceLe projet AVuPUR a pour objectif de progresser sur la compréhension et la modélisation des flux d'eau dans les bassins versants péri-urbains. Il s'agit plus particulièrement de fournir des outils permettant de quantifier l'impact d'objets anthropiques tels que zones urbaines, routes, fossés sur les régimes hydrologiques des cours d'eau dans ces bassins. Cet article présente la stratégie expérimentale et de collecte de données mise en ½uvre dans le projet et les pistes proposées pour l'amélioration des outils de modélisation existants et le développement d'outils novateurs. Enfin, nous présentons comment ces outils seront utilisés pour simuler et quantifier l'impact des modifications d'occupation des sols et/ou du climat sur les régimes hydrologiques des bassins étudiés. / The aim of the AVuPUR project is to enhance our understanding and modelling capacity of water fluxes within suburban watersheds. In particular, the objective is to deliver tools allowing to quantify the impact of anthropogenic elements such as urban areas, roads, ditches on the hydrological regime of suburban rivers. This paper presents the observation and data collection strategy set up by the project, and the directions for improving existing modelling tools or proposing innovative ones. Finally, we present how these tools will be used to simulate and quantify the impact of land use and climate changes on the hydrological regimes of the studied catchments

Quantification des incertitudes d'un jaugeage par profileur acoustique à effet Doppler

Stream gagings improve the knowledge of stage-discharge curves. Among the various techniques for discharge measures, the velocity field method consists in determining the velocity and the cross-sectional area of water flowing in open channels. There are different sensors and measurement procedures. Acoustic Doppler Current Profilers are river discharge instruments. A lot of data are acquired during the measurement sessions and also the post processing is complex. The " moving boat " is a deployment procedure for discharge measurements with ADCP (and measurements are difficult to assess). This study investigates a new operational method for uncertainty evaluation on discharge measurement made with ADCP on moving boats. This method is successfully tested on an array of discharge measurements in French rivers. Setting the appropriate parameters necessitates the adoption of some simple hypotheses, results are realistic. Good conditions stream gaugings show an uncertainty inferior to 4 % (k=2). To go further the method settings could be improved.Les jaugeages permettent à la fois de connaître le débit d'une rivière ponctuellement et de qualifier des stations de mesure du débit en continu (stations hydrométriques). Parmi les techniques de jaugeage, celles par exploration du champ des vitesses consistant à mesurer les vitesses de l'écoulement et la profondeur en différents points de la section sont les plus répandues. Les profileurs acoustiques à effet Doppler (ADCP) sont des instruments utilisés pour le jaugeage. La profusion et la complexité des mesures ADCP font que leur analyse nécessite des méthodes de post-traitement adaptées ; les incertitudes associées au débit jaugé par ADCP mobile sont difficiles à évaluer. L'objectif du travail est de mettre au point, tester et valider une méthodologie opérationnelle de calcul des incertitudes sur les débits issus de jaugeages complets par exploration du champ des vitesses par ADCP. Le paramétrage de la méthode implique quelques hypothèses simplificatrices. Les résultats obtenus sont réalistes, les jaugeages effectués dans les meilleures conditions présentent des incertitudes inférieures à 4 % (k=2). Pour aller plus loin, l'évaluation des différents paramètres peut encore être améliorée

Simulation des effets d'une hausse de 15 pourcents du prix du pétrole

info:eu-repo/semantics/publishe

Observation and modelling of sand fluxes in large rivers

Disposer de bilans de flux de sable dans les cours d'eau est important. Les enjeux socio-économiques sont multiples avec des aspects écologiques, industriels et de sécurité notamment. Les bilans de flux de sable restent actuellement difficiles à établir, du fait de la grande incertitude du peu de données existantes, ce qui ne permet pas un diagnostic et une prise de décision efficaces. Le sable des cours d'eau est transporté par charriage et suspension graduée. Les volumes de sable déplacés sont déterminés par la capacité de transport de l'écoulement et par la disponibilité des matériaux (apports amont, fond, berges). La motivation générale de cette thèse est de quantifier et réduire l'incertitude sur les flux de sable dans les grands cours d'eau par une approche à base physique. Ce travail explore les principales sources d'incertitude des jaugeages solides, liées à la représentativité des prélèvements, aux analyses, au calcul de flux dans la section. Il ressort que sans procédure d'analyse adaptée, la proportion de sable peut être fortement sous-estimée. Un protocole de mesure de terrain et une méthode alternative de calcul de flux sont proposées. La méthode combine des prélèvements ponctuels et des mesures ADCP (Acoustic Doppler Current Profiler). Cette approche est testée sur plusieurs grands fleuves (Colorado, Rhône, Mékong, Amazone). Plusieurs types de courbes de tarage de sable (empiriques ou à base physique) sont ensuite testées. Les résultats de jaugeages solides, combinés à des modèles de courbe de tarage de sable vont ensuite permettre, par une approche bayésienne, de déterminer des séries temporelles et des bilans de flux de sable ainsi que leurs incertitudes associéesSuspended-sand budgets estimation are important for hydrologists and river managers. It is required for river restoration and monitoring, river engineering, flood risk evaluation. Suspended-sand budgets are still difficult to establish, due to large uncertainty and scarce data, which does not allow appropriate diagnosis and decision making. Two main modes of sand transport are currently described : bedload and graded suspended load. The moving sand load depends both on the transport capacity of the river reach and on the supply of sand from upstream, river-bed and banks. The main motivation of this thesis is to quantify and reduce suspended-sand fluxes uncertainty in large rivers with a physically based approach. This work looks at the main uncertainty sources in suspended-sand flux data, related to sampling representativeness, sample analysis, and computation in the cross-section. One highlighted concern is that without a sand suitable analysis protocol, the amount of sand can be underestimated. A field measurement protocol and a surrogate method for suspended-sand flux computation in the cross-section are proposed. The method combines point sampling measurements and ADCP (Acoustic Doppler Current Profiler) data. This approach is applied on four large rivers in various morphological and flow conditions : the Colorado, Rhône, Mekong, and Amazon Rivers. Various sand rating curves approaches (physically based or empirical) are studied. The results of suspended sand flux measurements combined with suspended sand rating curve models allow, by a Bayesian approach, to determine continuous suspended-sand load, budgets and their associated uncertaintie