Modelo de escoamento multif��sico para estudo da intera����o onda/sedimento

Modelos de escoamento multif��sico s��o amplamente usados em diversas ��reas de pesquisa ambiental, como leitos fluidizados, dispers��o de g��s em l��quidos e v��rios outros processos que englobam mais de uma propriedade f��sico-qu��mica do meio. Dessa forma, um modelo multif��sico foi desenvolvido e adaptado para o estudo do transporte de sedimentos de fundo devido �� a����o de ondas de gravidade. Neste trabalho, foi elaborado o acoplamento multif��sico de um modelo euleriano n��o-linear de ondas do tipo Boussinesq, baseado na formula����o num��rica encontrada em Wei et al. (1995), com um modelo lagrangiano de part��culas, fundamentado pelo princ��pio Newtoniano do movimento com o esquema de colis��es do tipo esferas r��gidas. O modelo de ondas foi testado quanto �� sua fonte geradora, representada por uma fun����o gaussiana, p��-pist��o e p��-batedor, e quanto �� sua intera����o com a profundidade, atrav��s da n��o-linearidade e de propriedades dispersivas. Nos testes realizados da fonte geradora, foi observado que a fonte gaussiana, conforme Wei et al. (1999), apresentou melhor consist��ncia e estabilidade na gera����o das ondas, quando comparada �� teoria linear para um kh ��� ��� . A n��o-linearidade do modelo de ondas de 2�� ordem para a dispers��o apresentou resultados satisfat��rios quando confrontados com o experimento de ondas sobre um obst��culo trapezoidal, onde a deforma����o da onda sobre a estrutura submersa est�� em concord��ncia com os dados experimentais encontrados na literatura. A partir da��, o modelo granular tamb��m foi testado em dois experimentos. O primeiro simula uma quebra de barragem em um tanque contendo ��gua e o segundo, a quebra de barragem �� simulada com um obst��culo r��gido adicionado ao centro do tanque. Nesses experimentos, o algoritmo de colis��o foi eficaz no tratamento da intera����o entre part��cula-part��cula e part��cula-parede, permitindo a evid��ncia de processos f��sicos que s��o complicados de serem simulados por modelos de malhas regulares. Para o acoplamento do modelo de ondas e de sedimentos, o algoritmo foi testado com base de dados da literatura quanto �� morfologia do leito. Os resultados foram confrontados com dados anal��ticos e de modelos num��ricos, e se mostraram satisfat��rios com rela����o aos pontos de eros��o, de sedimenta����o e na altera����o da forma da barra arenosa

Conservation of a threatened European tree frog (Hyla arborea) metapopulation

Summary: Amphibians are among the most vulnerable animals of the world. One third of all species are currently threatened with extinction. Habitat loss is the major menace to pond- and stream-breeding species in the old world. In highly urbanized landscape like the Swiss Plateau, most species suffer from habitat reduction and fragmentation. Among all indigenous species, the European tree frog (Hyla arborea L., 1758) is one of the most endangered. It experienced an alarming decline during the last century and its regional long-term persistence is not guaranteed. We developed a monitoring framework based on calling male counts which included multiple visits to each wetland during the reproduction period in order to precisely determine its distribution on the Lemanic coast. Our results indicate that visiting populations 3 limes under suitable climatic conditions (temperature >20��C) provides reliable presence/absence data. Based on our monitoring data, we analyzed the species requirements regarding its breeding habitat. It appeared that anthropogenic activities had paradoxical effects on the species. On one hand, urbanization, traffic and intensive agriculture had a strong detrimental effect on tree frog distribution. On the other hand, large tree frog populations were frequently associated with gravel pits and military training grounds. Our results allowed us to create a habitat suitability map taking into account detrimental landscape elements around ponds (>1100m away from urban areas and >500m away from first class roads). In parallel, we developed a metapopulation model of the European tree frog in order to identify the critical threats to the long term persistence of the species. Our results indicated that suitable pond density is at the low end of the species requirements. Pond creation must therefore be considered an essential complementary approach to pond conservation and restoration. Our model also provided a mapping solution permitting the location of the must suitable area for pond creation from a metapopulation perspective. As many other amphibians, the European tree frog is not only exposed to an aquatic habitat (breeding and larval period), but also to a terrestrial stage (summer and overwintering habitats). Unfortunately, animals in their terrestrial phase are less conspicuous and, as a consequence, their terrestrial needs are relatively unknown. Using a recent tracking method (the Harmonic Direction Finder), we followed post-breeding frogs and identified favored terrestrial habitats, thus providing another practical conservation tool. We conclude that only the combination of multiple spatially explicit approaches (landscape-scale habitat suitability, metapopulation dynamics and terrestrial needs) is likely to provide wildlife managers with effective tools for the conservation of highly endangered amphibians. R��sum��: Les amphibiens font partie des animaux les plus vuln��rables du monde. Un tiers des esp��ces est actuellement menac�� d'extinction. Dans l'ancien monde, la disparition des habitats constitue la principale menace pour les grenouilles, crapauds, tritons et salamandres. Dans les paysages fortement urbanis��s comme le Plateau Suisse, la plupart des esp��ces souffrent d'une r��duction et d'une fragmentation de leurs habitats. Parmi toutes les esp��ces indig��nes, la rainette verte (Hyla arborea L., 1758) est l'une des plus menac��e. Sa distribution a r��gress�� de mani��re alarmante durant le si��cle pass�� et sa survie r��gionale �� long terme n'est pas assur��e. Nous avons d��velopp�� une m��thode de suivi des populations se basant sur le comptage des m��les chanteurs durant la p��riode de reproduction. Cette m��thode requiert plusieurs visites �� chaque plan d'eau de mani��re �� d��terminer pr��cis��ment la distribution de l'esp��ce. Nos r��sultats d��montrent que 3 visites par population dans des conditions climatiques favorable (temp��rature >20��C) permettent d'obtenir des donn��es de pr��sence/ absence valables. Sur la base de nos comptages sur la C��te l��manique, nous avons analys�� les exigences de l'esp��ce concernant ses sites de reproduction. Il est apparu que les activit��s humaines avaient un effet paradoxal sur l'esp��ce. D'une part, l'urbanisation, le trafic routier et l'intensification de l'agriculture ont un effet fortement pr��judiciable, tandis que d'autre part les plus grandes populations sont souvent associ��es �� des gravi��res et autres places d'armes. Nos r��sultats ont permis de cr��er une carte de qualit�� d'habitat prenant en compte les ��l��ments paysagers pr��judiciables �� la rainette (situ�� �� plus de 1100m de zones urbaines et �� plus de 500m de routes de premi��re classe). En parall��le, nous avons d��velopp�� un mod��le m��tapopulationnel (incluant l'ensemble des populations) de mani��re �� identifier les menaces pr��pond��rantes sur la survie �� long terme de l'esp��ce. Nos r��sultats ont permis de d��terminer que la densit�� actuelle de plans d'eau ad��quats est �� la limite inf��rieure des exigences de l'esp��ce. La cr��ation d'��tangs doit donc ��tre consid��r��e comme une approche indispensable et compl��mentaire �� la protection et �� la restauration des sites existants. Notre mod��le a ��galement fourni des r��sultats cartographiables permettant l'identification des sites les plus appropri��s dans une perspective m��tapopulationnelle. Comme de nombreux autres amphibiens, la rainette verte est expos��e �� un habitat aquatique (reproduction et d��veloppement larvaire) ainsi qu'�� un habitat terrestre (��t�� et hiver). Les animaux ��tant particuli��rement cryptiques dans cette seconde phase, leurs besoins terrestres sont relativement mal connus. Nous avons donc d��velopp�� une nouvelle m��thode de t��l��m��trie bas��e sur le goniom��tre harmonique. Cette m��thode nous a permis de suivre des rainettes dans leurs migrations jusqu'�� leurs habitats d'��t�� et d'��tablir ainsi des recommandations pratiques pour la conservation de la rainette. Nous concluons que la combinaison de multiples approches spatialement explicites (qualit�� d'habitat, dynamique de m��tapopulation et habitats terrestres) est seule �� m��me de produire des outils efficaces pour la conservation des esp��ces menac��es d'amphibiens.

Using 3D surface datasets to understand landslide evolution: From analogue models to real case study

Early detection of landslide surface deformation with 3D remote sensing techniques, as TLS, has become a great challenge during last decade. To improve our understanding of landslide deformation, a series of analogue simulation have been carried out on non-rigid bodies coupled with 3D digitizer. All these experiments have been carried out under controlled conditions, as water level and slope angle inclination. We were able to follow 3D surface deformation suffered by complex landslide bodies from precursory deformation still larger failures. These experiments were the basis for the development of a new algorithm for the quantification of surface deformation using automatic tracking method on discrete points of the slope surface. To validate the algorithm, comparisons were made between manually obtained results and algorithm surface displacement results. Outputs will help in understanding 3D deformation during pre-failure stages and failure mechanisms, which are fundamental aspects for future implementation of 3D remote sensing techniques in early warning systems.

Long time behaviour of diffusing particles in constrained geometries; application to chromatin motion

Inspired by experiments that use single-particle tracking to measure the regions of confinement of selected chromosomal regions within cell nuclei, we have developed an analytical approach that takes into account various possible positions and shapes of the confinement regions. We show, in particular, that confinement of a particle into a subregion that is entirely enclosed within a spherical volume can lead to a higher limit of the mean radial square displacement value than the one associated with a particle that can explore the entire spherical volume. Finally, we apply the theory to analyse the motion of extrachromosomal chromatin rings within nuclei of living yeast.

Thermal activation and ATP dependence of the cytoskeleton remodeling dynamics

The cytoskeleton (CSK) is a nonequilibrium polymer network that uses hydrolyzable sources of free energy such as adenosine triphosphate (ATP) to remodel its internal structure. As in inert nonequilibrium soft materials, CSK remodeling has been associated with structural rearrangements driven by energy-activated processes. We carry out particle tracking and traction microscopy measurements of alveolar epithelial cells at various temperatures and ATP concentrations. We provide the first experimental evidence that the remodeling dynamics of the CSK is driven by structural rearrangements over free-energy barriers induced by thermally activated forces mediated by ATP. The measured activation energy of these forces is ~40kBTr (kB being the Boltzmann constant and Tr being the room temperature). Our experiments provide clues to understand the analogy between the dynamics of the living CSK and that of inert nonequilibrium soft materials.

Hamiltonian formalism for nonlocal Lagrangians

A Hamiltonian formalism is set up for nonlocal Lagrangian systems. The method is based on obtaining an equivalent singular first order Lagrangian, which is processed according to the standard Legendre transformation and then, the resulting Hamiltonian formalism is pulled back onto the phase space defined by the corresponding constraints. Finally, the standard results for local Lagrangians of any order are obtained as a particular case.

Real-time Imaging and Mosaicking of Planar Surfaces

Laajojen pintojen kuvaaminen rajoitetussa ty��skentelytilassa riitt��v��ll�� kuvatarkkuudella voi olla vaikeaa. Kuvaaminen on suoritettava osissa ja osat koottava saumattomaksi kokonaisn��kym��ksi eli mosaiikkikuvaksi. Kuvauslaitetta k��sin siirtelev��n k��ytt��j��n on saatava v��lit��nt�� palautetta, jotta mosaiikkiin ei j��isi aukkoja ja ty�� olisi nopeaa. Ty��n tarkoituksena oli rakentaa pieni, kannettava ja tarkka kuvauslaite paperi- ja painoteollisuuden tarpeisiin sek�� kehitt���� palautteen antamiseen menetelm��, joka koostaaja esitt���� karkeaa mosaiikkikuvaa tosiajassa. Ty��ss�� rakennettiin kaksi kuvauslaitetta: ensimm��inen kuluttajille ja toinen teollisuuteen tarkoitetuista osista. Kuvamateriaali k��siteltiin tavallisella p��yt��tietokoneella. Videokuvien v��linen liike laskettiin yksinkertaisella seurantamenetelm��ll�� ja mosaiikkikuvaa koottiin kameroiden kuvanopeudella. Laskennallista valaistuksenkorjausta tutkittiin ja kehitetty menetelm�� otettiin k��ytt����n. Ensimm��isess�� kuvauslaitteessa on ongelmia valaistuksen ja linssiv����ristymien kanssa tuottaen huonolaatuisia mosaiikkikuvia. Toisessa kuvauslaitteessa n��m�� ongelmat on korjattu. Seurantamenetelm�� toimii hyvin ottaen huomioon sen yksinkertaisuuden ja siihen ehdotetaan monia parannuksia. Ty��n tulokset osoittavat, ett�� tosiaikainen mosaiikkikuvan koostaminen megapikselin kuvamateriaalista on mahdollista kuluttajille tarkoitetulla tietokonelaitteistolla.

Development of advanced silicon radiation detectors for harsh radiation environment

This thesis describes the development of advanced silicon radiation detectors and their characterization by simulations, used in the work for searching elementary particles in the European Organization for Nuclear Research, CERN. Silicon particle detectors will face extremely harsh radiation in the proposed upgrade of the Large Hadron Collider, the future high-energy physics experiment Super-LHC. The increase in the maximal fluence and the beam luminosity up to 1016 neq / cm2 and 1035 cm-2s-1 will require detectors with a dramatic improvement in radiation hardness, when such a fluence will be far beyond the operational limits of the present silicon detectors. The main goals of detector development concentrate on minimizing the radiation degradation. This study contributes mainly to the device engineering technology for developing more radiation hard particle detectors with better characteristics. Also the defect engineering technology is discussed. In the nearest region of the beam in Super-LHC, the only detector choice is 3D detectors, or alternatively replacing other types of detectors every two years. The interest in the 3D silicon detectors is continuously growing because of their many advantages as compared to conventional planar detectors: the devices can be fully depleted at low bias voltages, the speed of the charge collection is high, and the collection distances are about one order of magnitude less than those of planar technology strip and pixel detectors with electrodes limited to the detector surface. Also the 3D detectors exhibit high radiation tolerance, and thus the ability of the silicon detectors to operate after irradiation is increased. Two parameters, full depletion voltage and electric field distribution, is discussed in more detail in this study. The full depletion of the detector is important because the only depleted area in the detector is active for the particle tracking. Similarly, the high electric field in the detector makes the detector volume sensitive, while low-field areas are non-sensitive to particles. This study shows the simulation results of full depletion voltage and the electric field distribution for the various types of 3D detectors. First, the 3D detector with the n-type substrate and partial-penetrating p-type electrodes are researched. A detector of this type has a low electric field on the pixel side and it suffers from type inversion. Next, the substrate is changed to p-type and the detectors having electrodes with one doping type and the dual doping type are examined. The electric field profile in a dual-column 3D Si detector is more uniform than that in the single-type column 3D detector. The dual-column detectors are the best in radiation hardness because of their low depletion voltages and short drift distances.

Subcellular Redistribution of Root Aquaporins Induced by Hydrogen Peroxide.

Aquaporins are water channel proteins that mediate the fine-tuning of cell membrane water permeability during development or in response to environmental stresses. The present work focuses on the oxidative stress-induced redistribution of plasma membrane intrinsic protein (PIP) aquaporins��from the plasma membrane (PM) to intracellular membranes. This process was investigated in the Arabidopsis root. Sucrose density gradient centrifugation showed that exposure of roots to 0.5��mM H2O2 induces significant depletion in PM fractions of several abundant PIP homologs after 15��min. Analyses by single-particle tracking and fluorescence correlative spectroscopy showed that, in the PM of epidermal cells, H2O2 treatment induces an increase in lateral motion and a reduction in the density of a fluorescently tagged form of the prototypal AtPIP2;1 isoform, respectively. Co-expression analyses of AtPIP2;1 with endomembrane markers revealed that H2O2 triggers AtPIP2;1 accumulation in the late endosomal compartments. Life-time analyses established that the high stability of PIPs was maintained under oxidative stress conditions, suggesting that H2O2 triggers a mechanism for intracellular sequestration of PM aquaporins��without further degradation. In addition to information on cellular regulation of aquaporins, this study provides novel and complementary insights into the dynamic remodeling of plant internal membranes during oxidative stress responses.

Tunkeuman hallinta MIG/MAG-hitsauksessa

MIG/MAG-hitsaukselle tyypillinen ominaispiirre, valokaaren itses����tyvyys, saavutetaan vakioj��nnitel��hdett�� k��ytt��m��ll��. Valokaaren sis��isen s����t��mekanismin ansiosta kaarenpituus pysyy vakiona, vaikka hitsauspolttimen ja ty��kappaleen v��linen et��isyys vaihtelisi hitsauksen aikana. Vakioj��nnitel��hteen k��ytt��minen aiheuttaa kuitenkin kaaritehon vaihtelua vapaalankapituuden muuttuessa. Vapaalangan kasvaessa liian pitk��ksi kaariteho laskee niin alas, ettei se en���� riit�� sulattamaan tarpeeksi perusainetta railon kyljiss��. T��m��n seurauksena hitsausliitokseen syntyy erilaisia liittym��virheit��. K��sinhitsauksessa vapaalangan pituus saattaa polttimen ep��vakaasta kuljetuksesta johtuen vaihdella erityisesti kokemattomilla hitsaajilla. Mekanisoidussa ja automatisoidussa hitsauksessa railojen mitta- ja muotopoikkeamat aiheuttavat vapaalankapituuden vaihtelua. Poikkeamia syntyy kaikissa hitsausrailojen esivalmistusvaiheissa. Lis��ksi l��mm��ntuonnin aiheuttamat muodonmuutokset kappaleissa lis����v��t poikkeamia railonsovituksessa hitsauksen aikana. Ongelma on useimmiten ratkaistavissa railonseurantaa k��ytt��m��ll��. Railonseurantaj��rjestelm��t ovat kuitenkin kalliita, eiv��tk�� ne toimi luotettavasti kaikissa olosuhteissa. Diplomity��ss�� tutkittiin uutta MIG/MAG-hitsauksen reaaliaikaiseen tunkeuman hallintaan kehitetty�� s����t��j��rjestelm����. Ty��n tavoitteina olivat s����t��j��rjestelm��n luotettavan toiminnan takaavien reunaehtojen ja kosketussuutinet��isyyden suositusrajojen m����ritt��minen. Tavoitteiden t��ytt��miseksi ty��n kokeellisessa osiossa suoritettiin laaja hitsauskokeiden sarja, jossa hitsattavina materiaaleina k��ytettiin seostamatonta ja runsasseosteista ter��st��.

Readout electronics for low dark count pixel detectors based on geiger mode avalanche photodiodes fabricated in conventional CMOS technologies for future linear colliders

The high sensitivity and excellent timing accuracy of Geiger mode avalanche photodiodes makes them ideal sensors as pixel detectors for particle tracking in high energy physics experiments to be performed in future linear colliders. Nevertheless, it is well known that these sensors suffer from dark counts and afterpulsing noise, which induce false hits (indistinguishable from event detection) as well as an increase of the necessary area of the readout system. In this work, we present a comparison between APDs fabricated in a high voltage 0.35 ��m and a high integration 0.13 ��m commercially available CMOS technologies that has been performed to determine which of them best fits the particle collider requirements. In addition, a readout circuit that allows low noise operation is introduced. Experimental characterization of the proposed pixel is also presented in this work.

Readout architectures for hybrid pixel detector readout chips

The original contribution of this thesis to knowledge are novel digital readout architectures for hybrid pixel readout chips. The thesis presents asynchronous bus-based architecture, a data-node based column architecture and a network-based pixel matrix architecture for data transportation. It is shown that the data-node architecture achieves readout efficiency 99% with half the output rate as a bus-based system. The network-based solution avoids ���broken��� columns due to some manufacturing errors, and it distributes internal data traffic more evenly across the pixel matrix than column-based architectures. An improvement of > 10% to the efficiency is achieved with uniform and non-uniform hit occupancies. Architectural design has been done using transaction level modeling (TLM) and sequential high-level design techniques for reducing the design and simulation time. It has been possible to simulate tens of column and full chip architectures using the high-level techniques. A decrease of > 10 in run-time is observed using these techniques compared to register transfer level (RTL) design technique. Reduction of 50% for lines-of-code (LoC) for the high-level models compared to the RTL description has been achieved. Two architectures are then demonstrated in two hybrid pixel readout chips. The first chip, Timepix3 has been designed for the Medipix3 collaboration. According to the measurements, it consumes < 1 W/cm^2. It also delivers up to 40 Mhits/s/cm^2 with 10-bit time-over-threshold (ToT) and 18-bit time-of-arrival (ToA) of 1.5625 ns. The chip uses a token-arbitrated, asynchronous two-phase handshake column bus for internal data transfer. It has also been successfully used in a multi-chip particle tracking telescope. The second chip, VeloPix, is a readout chip being designed for the upgrade of Vertex Locator (VELO) of the LHCb experiment at CERN. Based on the simulations, it consumes < 1.5 W/cm^2 while delivering up to 320 Mpackets/s/cm^2, each packet containing up to 8 pixels. VeloPix uses a node-based data fabric for achieving throughput of 13.3 Mpackets/s from the column to the EoC. By combining Monte Carlo physics data with high-level simulations, it has been demonstrated that the architecture meets requirements of the VELO (260 Mpackets/s/cm^2 with efficiency of 99%).

Exploitation de contraintes photom��triques et g��om��triques en vision : application au suivi, au calibrage et �� la reconstruction

Cette th��se a ��t�� r��alis��e dans le cadre d'une cotutelle avec l'Institut National Polytechnique de Grenoble (France). La recherche a ��t�� effectu��e au sein des laboratoires de vision 3D (DIRO, UdM) et PERCEPTION-INRIA (Grenoble).

Regional Differences in the Prediction of Extratropical Cyclones by the ECMWF Ensemble Prediction System

A regional study of the prediction of extratropical cyclones by the European Centre for Medium-Range Weather Forecasts (ECMWF) Ensemble Prediction System (EPS) has been performed. An objective feature-tracking method has been used to identify and track the cyclones along the forecast trajectories. Forecast error statistics have then been produced for the position, intensity, and propagation speed of the storms. In previous work, data limitations meant it was only possible to present the diagnostics for the entire Northern Hemisphere (NH) or Southern Hemisphere. A larger data sample has allowed the diagnostics to be computed separately for smaller regions around the globe and has made it possible to explore the regional differences in the prediction of storms by the EPS. Results show that in the NH there is a larger ensemble mean error in the position of storms over the Atlantic Ocean. Further analysis revealed that this is mainly due to errors in the prediction of storm propagation speed rather than in direction. Forecast storms propagate too slowly in all regions, but the bias is about 2 times as large in the NH Atlantic region. The results show that storm intensity is generally overpredicted over the ocean and underpredicted over the land and that the absolute error in intensity is larger over the ocean than over the land. In the NH, large errors occur in the prediction of the intensity of storms that originate as tropical cyclones but then move into the extratropics. The ensemble is underdispersive for the intensity of cyclones (i.e., the spread is smaller than the mean error) in all regions. The spatial patterns of the ensemble mean error and ensemble spread are very different for the intensity of cyclones. Spatial distributions of the ensemble mean error suggest that large errors occur during the growth phase of storm development, but this is not indicated by the spatial distributions of the ensemble spread. In the NH there are further differences. First, the large errors in the prediction of the intensity of cyclones that originate in the tropics are not indicated by the spread. Second, the ensemble mean error is larger over the Pacific Ocean than over the Atlantic, whereas the opposite is true for the spread. The use of a storm-tracking approach, to both weather forecasters and developers of forecast systems, is also discussed.

TIGGE: Comparison of the prediction of northern hemisphere extratropical cyclones by different ensemble prediction systems

The Observing System Research and Predictability Experiment (THORPEX) Interactive Grand Global Ensemble (TIGGE) is a World Weather Research Programme project. One of its main objectives is to enhance collaboration on the development of ensemble prediction between operational centers and universities by increasing the availability of ensemble prediction system (EPS) data for research. This study analyzes the prediction of Northern Hemisphere extratropical cyclones by nine different EPSs archived as part of the TIGGE project for the 6-month time period of 1 February 2008���31 July 2008, which included a sample of 774 cyclones. An objective feature tracking method has been used to identify and track the cyclones along the forecast trajectories. Forecast verification statistics have then been produced [using the European Centre for Medium-Range Weather Forecasts (ECMWF) operational analysis as the truth] for cyclone position, intensity, and propagation speed, showing large differences between the different EPSs. The results show that the ECMWF ensemble mean and control have the highest level of skill for all cyclone properties. The Japanese Meteorological Administration (JMA), the National Centers for Environmental Prediction (NCEP), the Met Office (UKMO), and the Canadian Meteorological Centre (CMC) have 1 day less skill for the position of cyclones throughout the forecast range. The relative performance of the different EPSs remains the same for cyclone intensity except for NCEP, which has larger errors than for position. NCEP, the Centro de Previs��o de Tempo e Estudos Clim��ticos (CPTEC), and the Australian Bureau of Meteorology (BoM) all have faster intensity error growth in the earlier part of the forecast. They are also very underdispersive and significantly underpredict intensities, perhaps due to the comparatively low spatial resolutions of these EPSs not being able to accurately model the tilted structure essential to cyclone growth and decay. There is very little difference between the levels of skill of the ensemble mean and control for cyclone position, but the ensemble mean provides an advantage over the control for all EPSs except CPTEC in cyclone intensity and there is an advantage for propagation speed for all EPSs. ECMWF and JMA have an excellent spread���skill relationship for cyclone position. The EPSs are all much more underdispersive for cyclone intensity and propagation speed than for position, with ECMWF and CMC performing best for intensity and CMC performing best for propagation speed. ECMWF is the only EPS to consistently overpredict cyclone intensity, although the bias is small. BoM, NCEP, UKMO, and CPTEC significantly underpredict intensity and, interestingly, all the EPSs underpredict the propagation speed, that is, the cyclones move too slowly on average in all EPSs.