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A study on wildfire impacts on greenhouse gas emissions and regional air quality in South of Orléans,France

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Journal of Environmental Sciences 2024年第1期135卷 521-533页

作者： Chaoyang Xue Gisèle Krysztofiak Yangang Ren Min Cai Patrick Mercier Frédéric Le Fur Corinne Robin Benoit Grosselin Véronique Daele Max RMcGillen Yujing Mu Valéry Catoire Abdelwahid Mellouki Laboratoire de Physique et Chimie de l’Environnement et de l’Espace(LPC2E) CNRS–UniversitéOrléans–CNES(UMR 7328)Orléans Cedex 245071France Institut de Combustion AérothermiqueRéactivitéEnvironnement(ICARE)CNRSOrléans Cedex 245071France Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Lig’Air-Association de surveillance de la qualitéde l’air en région Centre-Val de Loire Saint-Cyr-en-Val 45590France Mohammed V University RabatMorocco

Wildfire events are increasing globally which may be partly associated with climate change,resulting in significant adverse impacts on local,regional air quality and global climate.In September 2020,a small wildfire(burned area:36.3 ha)event occurred in Souesmes(Loiret-Cher,Sologne,France),and its plume spread out over 200 km on the following day as observed by the MODIS satellite.Based on measurements at a suburban site(~50 km northwest of the fire location)in Orléans and backward trajectory analysis,young wildfire plumes were characterized.Significant increases in gaseous pollutants(CO,CH_(4),N_(2)O,VOCs,etc.)and particles(including black carbon)were found within the wildfire plumes,leading to a reduced air quality.Emission factors,defined as EF(X)=ΔX/ΔCO(where,X represents the target species),of various trace gases and black carbon within the young wildfire plumes were determined accordingly and compared with previous studies.Changes in the ambient ions(such as ammonium,sulfate,nitrate,chloride,and nitrite in the particle-and gasphase)and aerosol properties(e.g.,aerosol water content,aerosol p H)were also quantified and discussed.Moreover,we estimated the total carbon and climate-related species(e.g.,CO_(2),CH_(4),N_(2)O,and BC)emissions and compared them with fire emission inventories.Current biomass burning emission inventories have uncertainties in estimating small fire burned areas and emissions.For instance,we found that the Global Fire Assimilation System(GFAS)may underestimate emissions(e.g.,CO)of this small wildfire while other inventories(GFED and FINN)showed significant overestimation.Considering that it is the first time to record wildfire plumes in this region,related atmospheric implications are presented and discussed.

关键词： Wildfire Air quality Emission factor Emission inventory VOLTAIRE supersite

Littoral landforms of Lake Hulun and Lake Buir(China and Mongolia):Wind-driven hydro-sedimentary dynamics and resulting clastics distribution

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Journal of Palaeogeography 2024年第2期13卷 309-326页

作者： Li Wang Mathieu Schuster Shi-Wei Xin Florin Zainescu Xin-Yu Xue Joep Storms Jan-Hendrik May Alexis Nutz Helena van der Vegt Guilherme Bozetti Zai-Xing Jiang School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Universite de Strasbourg CNRSENGEESInstitut Terre et Environnement de StrasbourgUMR 70635 Rue DescartesStrasbourgFrance Tamsag Mongolia(XIX)Ltd. PetroChinaDaqing 163000China CEREGE Aix-Marseille UniversitéCNESIRDCollege de FranceINRAAix en ProvenceFrance School of Marine Science Sun Yat-sen UniversityZhuhai 519083China Delft University of Technology Department of Geoscience and EngineeringDelfthe Netherlands School of Geography Earth and Atmospheric SciencesUniversity of Melbourne253 Elgin St.CarltonVIC 3053Australia Deltares Delfthe Netherlands SCMF Faculty of GeographyUniversity of Bucharest1 N.Balcescu Blv.BucharestRomania

Two rectangular-shaped lakes,Lake Hulun and Lake Buir,located at the boundary between China and Mongolia,only c.75 km apart and therefore experiencing similar wind fields,have been studied based on satellite images and field surveys in order to compare their geomorphological and sedimentological characteristics.The wind-driven hydrodynamics,which have a significant effect on the development of littoral landforms and on sediment distribution,have been discussed for the two similar lakes that experienced a prevailing wind perpendicular to their long axis.A conceptual model related to wind-driven water bodies and sediment distribution is proposed.Wave-influenced to wave-dominated deltas,beaches,spits,and eolian dune deposits develop around these two lakes,with a strikingly similar distribution pattern.These features locally inform the longshore drift and help reconstruct the water circulation induced by wind forcing.Under the NW prevailing wind regime,the spits developed on the SW coast with a NW—SE extension,which was influenced by the NW—SE longshore currents.The same influence was observed in the delta extension in the NE area.The differences lie in the presence of fan deltas in the NW region of Lake Hulun,but not in Lake Buir.Additionally,the width of the beach and eolian deposits on the downwind coast of Lake Hulun is three times greater than that of Lake Buir which were caused by the differences in sediment supply and wind fetch between the two lakes.Lake Hulun and Lake Buir provide two reliable examples to understand the relationship among the wind field,provenance,hydrodynamics,landforms,and asymmetrical distribution of clastics in elongated lakes.They also represent relevant modern analogs,which may also be of guiding significance to wind-driven sand body prediction in lacustrine basins.

关键词： Wind-driven lakes Fetch Sedimentary facies Hydrodynamics Geomorphology Spits Shoreline Lake Hulun Lake Buir

Words as tracers in the history of science and technology:the case of photogrammetry and remote sensing

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Geo-Spatial Information Science 2021年第1期24卷 167-177,I0018页

作者： Laurent Polidori CESBIO Universitéde ToulouseCNES/CNRS/INRAE/IRD/UPSToulouseFrance

The evolution of terminology in a given field of science and technology is a good indicator of the context in which inventions originated and how concepts have evolved.This is the case of photogrammetry,remote sensing and related methods,whose terminology evolved,first under the influence of the early inventors Laussedat and Meydenbauer,in French and German,respectively,and then in English and other languages as an international professional community developed.The development of space remote sensing and analytical photogrammetry led to the modification of old concepts and the renewal of terminology,and more recently,the advent of digital photography has blurred the boundaries between different fields and the meaning of the terms.This article proposes an analysis of the evolution of technical terms through the Google Ngram Viewer tool,which allows the visualization of the occurrence of terms in documents accessible on the web.Despite its biases,this tool allows an interpretation of the evolution of the terminology over a long period of time,as well as a comparison of the evolution observed in the different languages.In particular,it makes it possible to highlight the periods when these methods were very popular,as well as a recent decline in the use of classical terms such as photogrammetry and remote sensing in favor of a new vocabulary,due to the blurring of boundaries between disciplines and to the emergence of new solutions related to UAVs,computer vision,etc.,which have renewed the potential of classical methods.

关键词： Photogrammetry remote sensing terminology Ngram Viewer

Development and Evolution of the Size of Polygonal Fracture Systems during Fluid-Solid Separation in Clay-Rich Deposits

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Journal of Earth Science 2018年第6期29卷 1319-1334页

作者： Teodolina Lopez Raphael Antoine JoséDarrozes Michel Rabinowicz David Baratoux CESBIO Universite de ToulouseCNES/CNRS/IRD/UPSloulousePrance International Space Science Institute(ISSI) BernSwitzerland CEREMA Laboratoire Regional de RouenGroupe Sciences de la TerreCS 90245F-76121 Le Grand QuevillyFrance GET Universite de ToulouseUPS/CNRS/IRD/CNESToulouseFrance Institut Fondamental d'Afrique Noire(IFAN) Cheikh Anta DioDakarSenegal

In continental and oceanic conditions, clay-rich deposits are characterised by the development of polygonal fracture systems（PFS）. PFS can increase the vertical permeability of clay-rich deposits（mean permeability ≤10-16 m2） and are pathways for fluids. On continents, the width of PFS ranges from centimeters to hundreds of meters, while in oceanic contexts they are up to a few kilometers large. These structures are linked to water-solid separation during deposition, consolidation and complete fluid squeeze of the clay horizon. During the last few decades, modeling of melt migration in partially molten plastic rocks led to rigorous quantifications of two-phase flows with a particular emphasis on 2D and 3D induced flow structures. The numerical modeling shows that the melt migrates on distances almost equal to a few times the compaction length L that depends on permeability and viscosity. Consequently, polygonal structures in partially molten plastic rocks are resulted from the melt-rock separation and their sizes are proportional to L. Applying these results to fluid-solid separation in clay-rich horizons, we show that（1） centimetric to kilometric PFS are resulted from the dramatic increase of L during compaction and（2）, this process involves agglomerates with 100 μm to 1 mm size.

关键词： compaction clay deposit agglomerates polygonal fractures desiccation cracks

Review of Mercury's dynamic magnetosphere:Post-MESSENGER era and comparative magnetospheres

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Science China Earth Sciences 2022年第1期65卷 25-74页

作者： Weijie SUN Ryan MDEWEY Sae AIZAWA Jia HUANG James A.SLAVIN Suiyan FU Yong WEI Charles F.BOWERS Department of Climate and Space Sciences and Engineering University of MichiganAnn ArborMl 48109USA Institut de Recherche en Astrophysique et Planetologie CNRS-UPS-CNESToulouse 31400France Department of Geophysics Graduate School of ScienceTohoku UniversitySendai 980-8578Japan School of Earth and Space Sciences Peking UniversityBeijing 100871China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100864China

This review paper summarizes the research of Mercury’s magnetosphere in the Post-MESSENGER era and compares its dynamics to those in other planetary magnetospheres,especially to those in Earth’s magnetosphere.This review starts by introducing the planet Mercury,including its interplanetary environment,magnetosphere,exosphere,and conducting core.The frequent and intense magnetic reconnection on the dayside magnetopause,which is represented by the flux transfer event"shower",is reviewed on how they depend on magnetosheath plasma β and magnetic shear angle across the magnetopause,followed by how it contributes to the flux circulation and magnetosphere-surface-exosphere coupling.In the next,Mercury’s magnetosphere under extreme solar events,including the core induction and the reconnection erosion on the dayside magnetosphere,as well as the responses of the nightside magnetosphere,are reviewed.Then,the dawn-dusk properties of the plasma sheet,including the features of the ions,the structure of the current sheet,and the dynamics of magnetic reconnection,are summarized.The last topic is devoted to the particle energization in Mercury’s magnetosphere,which includes the energization of the Kelvin-Helmholtz waves on the magnetopause boundaries,reconnection-generated magnetic structures,and the cross-tail electric field.In each chapter,the last section discusses the open questions related to each topic,which can be considered by the simulations and the future spacecraft mission.We end this paper by summarizing the future Bepi Colombo opportunities,which is a joint mission of ESA and JAXA and is en route to Mercury.

关键词： Mercury’s magnetosphere Flux transfer event shower Extreme solar events Core induction Reconnection erosion Dawn-dusk asymmetry Substorm current wedge Particle energization Kelvin-Helmholtz wave

Geodynamic evolution of the Tethyan lithosphere as recorded in the Spontang Ophiolite,South Ladakh ophiolites(NW Himalaya,India)

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Geoscience Frontiers 2022年第1期13卷 326-349页

作者： Mallika K.Jonnalagadda Mathieu Benoit Shivani Harshe Romain Tilhac Raymond A.Duraiswami Michel Grégoire Nitin R.Karmalkar Interdisciplinary School of Science Savitribai Phule Pune UniversityPune 411007India Department of Geology Savitribai Phule Pune UniversityPune 411007India Géosciences Environnement Toulouse CNRS-CNES-IRD-UniversitéPaul SabatierObservatoire Midi Pyrénées31400 ToulouseFrance Instituto Andaluz de Ciencias de la Tierra(IACT) CSIC–Universidad de Granada18100 ArmillaGranadaSpain Vice-Chancellor’s Office Savitribai Phule Pune UniversityPune 411007India

The Spontang Ophiolite complex represents the most complete ophiolite sequence amongst the South Ladakh ophiolites and comprises mantle rocks(depleted harzburgites,dunites and minor lherzolites)as well as crustal rocks(basalt,isotropic gabbros,layered gabbros etc.).In the present study,detailed geochemistry(whole rock as well as mineral chemistry)and Sr-Nd isotopic analyses of thirty-six ultramaficmafic samples have been attempted to constraint the evolution and petrogenetic history of the Tethyan oceanic crust.Major,trace-element and REE patterns of the peridotites and their minerals indicate that the lherzolites experienced lower degrees of partial melting resembling abyssal peridotites(at higher temperatures,TREE=$1216℃)than the harzburgites(6%–8%versus 15%–17%).Elevated eNd(t)and variable^(87) Sr/^(86) Sr(t)ratios along with REE patterns suggest that the Spontang mafic rocks display N-MORB affinity with negligible participation of oceanic sediments in their genesis are originated from a depleted upper mantle with little contribution from subduction-related fluids.MORB-type Neotethyan oceanic crust is associated with the earliest phase of subduction(of older Jurassic age)through which a younger intra-oceanic island arc(Spong arc)subsequently developed.Harzburgites REE display typical U-shaped patterns,suggesting that these rocks have been metasomatized by LREE-enriched fluids.On the other side,mafic rocks are characterized by heterogeneous(Nb/La)PMand(Hf/Sm)PMand relatively homogeneous eNd(t),indicating interaction of subduction-related melts with the upper mantle during the initiation of subduction,in Early Cretaceous times.

关键词： Peridotites Mafic rocks Partial melting Metasomatism Ladakh

A cloud detection method based on a time series of MODIS surface reflectance images

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International Journal of Digital Earth 2013年第S1期6卷 157-171页

作者： Hairong Tang Kai Yu Olivier Hagolle Kang Jiang Xiurui Geng Yongchao Zhao Key Laboratory of Technology in Geo-spatial information Processing and Application System Institute of ElectronicsChinese Academy of ScienceBeijingChina CESBIO Universite´de ToulouseUnite´mixte CNES CNRS IRD UPSToulouse Cedex 4France

The Moderate Resolution Imaging Spectroradiometer(MODIS)-Terra surface reflectance product(MOD09A1),with bands 1 to 7,is a gridded,eight-day composite product derived from the MODIS-Terra top of atmosphere reflectance swaths.It performs cloud detection and corrects for the effects of atmospheric gases and aerosols.The cloud mask(CM)algorithms for MODIS are based on empirical thresholds on spectral reflectance and brightness temperature.Since the spatial resolution of the thermal band is 1000 m,while that of MOD09A1 is 500 m,many undetected and false clouds are observed in MOD09A1.These errors always result in temporal and spatial inconsistencies in higher-level products.In this paper,a cloud detection algorithm(TSCD)based on a MOD09A1 time series is introduced.Time series cloud detection(TSCD)algorithm is based on the relative stability of ground reflectance and the sudden variations in reflectance that result from cloud cover.The algorithm first searches the clear-sky reference data,and then discriminates clouded and unclouded pixels by detecting a sudden change of reflectance in the blue wavelength and spectral correlation coefficient at the pixel level.Compared with cloud cover assessments obtained from MODIS’original CM,TSCD provides similar or better discrimination in most situations when the land surface changes slowly.

关键词： MODIS surface reflectance time series cloud detection BRDF

Hydrological Variability from Gauging Stations and Simulated SWOT Data, for Major French Rivers

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Journal of Geoscience and Environment Protection 2017年第13期5卷 54-69页

作者： L. Chevalier B. Laignel I. Turki F. Lyard C. Lion cnes/LEGOS University of Toulouse Toulouse France University of Rouen Rouen France

This study was carried out under the aegis of the program Surface Water and Ocean Topography (SWOT) associated with the National Center of Space Studies (cnes). The future SWOT mission will offer new opportunities to survey the hydrodynamic in the rivers because it will provide data on the water level/ discharges with a high spatial resolution (oceans: 1 km, rivers: 100 m of width) and with a global cover. However, it is important to estimate the capacity of SWOT to reproduce the hydrodynamic phenomena in the estuaries and the temporal and the spatial variability of this dynamic. The aim of this paper is 1) to estimate the capacity of SWOT to reproduce the hydrological variability of watersheds, and 2) to validate the use of these data for other zone without hydrometric station. Based on discharge measurements and simulated Surface Water and Ocean Topography (SWOT) data, we have investigated the hydrological variability of the main French rivers (Seine, Loire, Garonne and Rh?ne) by applying a series of statistical analyses to the discharge time series. A frequency analysis has been also used using a technique of wavelet. Results have shown a similar hydrological variability of the four watersheds. Three different periods of hydrologic variability has been identified: before 1970, between 1970 and 1990, and after 1990. Using these analyses, simulated SWOT samples and discharges were compared during the three studied periods. Simulated SWOT data, obtained by a synthetic sampling of river discharges basing on the number of measurements per repeat orbit, reproduce the hydrological variability of rivers. Such reproduction seems to be independent in the number of SWOT passages (from two to four), except for the minimum and maximum annual discharges where number of overpass seems to have an influence. These results were validated by coherence wavelet which underlines coherence higher than 90% between simulated SWOT data and in-situ discharges. Nevertheless, good correlation was not observed for the minimum and the maxim

关键词： Hydrological Variability Discharge SWOT Watershed Wavelet Analyses

About Lorentz Invariance and Gauge Symmetries: An Alternative Approach to Relativistic Gravitation

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Natural Science 2014年第16期6卷 1244-1252页

作者： Richard Bonneville Centre National d’Etudes Spatiales (cnes) 2 Place Maurice Quentin Paris France

An alternative presentation of a relativistic theory of gravitation, equivalent to general relativity, is given. It is based upon the restriction of the Lorentz invariance of special relativity from a global invariance to a local one. The resulting expressions appear rather simple as we consider the transformations of a local set of pseudo-orthonormal coordinates and not the geometry of a 4-dimension hyper-surface described by a set of curvilinear coordinates. This is the major difference with the usual presentations of general relativity but that difference is purely formal. The usual approach is most adequate for describing the universe on a large scale in astrophysics and cosmology. The approach of this paper, derived from particle physics and focused on local reference frames, underlines the formal similarity between gravitation and the other interactions inasmuch as they are associated to the restriction of gauge symmetries from a global invariance to a local one.

关键词： Gravitation General Relativity Gauge Symmetries