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Ozone profiles retrieved from Global Ozone Monitoring Experiment (GOME, flying on ERS-2 satellite) spectra from July 1995 to June 2003 by means of 2 independent neural network (NN) schemes have been validated with ozone lidar measurements performed at different stations belonging to the network for the detection of atmospheric composition changes (NDACC). The retrieval and the whole validation have been carried out by using the performances and resources of the European project Enabling Grid for E-sciencE (EGEE) and of a local Grid at the European Space Research Institute of the European Space Agency (ESRIN/ESA). Roughly 1800 collocated profiles have been found, in tropical, mid-latitude and high-latitude regions; for each lidar station the differences between GOME and lidar profiles have been evaluated and the global performance of the proposed NN approaches has been critically discussed. The results indicate the potentialities for obtaining reliable ozone field analysis on global scale, including detailed altitude resolved trend analysis.

This paper presents the results of a unique opportunity of analyzing a large drop-size-distribution (DSD) sample. Using a well calibrated Optical Spectro Pluviometer sensor for measuring 1-min DSDs, a sample of one year and seven months of tropical rain has been collected in San Jose, Costa Rica. In addition, a quality control procedure was applied to the sample in order to construct a very robust data set. We examined frequency distributions of some DSD-derived parameters (such as rainrate, reflectivity, liquid-water content, median and mean volume diameters). Distinct shapes of average DSDs are observed for convective, transition, and stratiform rain. It is found that the transition and the stratiform curves are parallel. In terms of drop growth, this suggests that stratiform and transition raindrops evolve by similar physical process. Stratifying the DSDs by precipitation types based on physical criteria, prior to normalization, leads to very distinct normalized shapes. Thus, the idea that all DSDs can be represented by a single two-parameter normalization does not apply in our case. Overall, the results indicate that many of the microphysical characteristics of the rain in the sample resemble the ones observed in orographic rain at Hawaii.

Dimensionality reduction can be of crucial importance in the application of inversion schemes to atmospheric remote sensing data. In this study the problem of dimensionality reduction in the retrieval of ozone concentration profiles from the radiance measurements provided by the instrument Global Ozone Monitoring Experiment (GOME) on board of ESA satellite ERS-2 is considered. By means of radiative transfer modelling, neural networks and pruning algorithms, a complete procedure has been designed to extract the GOME spectral ranges most crucial for the inversion. The quality of the resulting retrieval algorithm has been evaluated by comparing its performance to that yielded by other schemes and co-located profiles obtained with lidar measurements.

The purpose of this work is the estimation of Doppler echoes spectral moments. In case of strong overlapping, Fourier-like techniques provide poor results because of the lack of resolution. We propose the use of stochastic maximum-likelihood (SML) and subspace-based methods (WPSF algorithm) for a joint estimation of spectral moments. The statistical performances (theoretical and empirical by Monte Carlo simulations) of estimators are compared with the Cramer-Rao lower bound. The results of tests performed on very high frequency (VHF) times series obtained during Thunderstorm, Arecibo, PR during September and October 1998 validate the model and algorithms and confirm the interest of both approaches.

Previous studies have shown that ageostrophic circulations play an important role in frontogenesis phenomena. They result from the maintenance of the balanced state of the atmosphere which tends to be broken down by the large-scale forcing of the atmosphere. Their existence explains how a frontal discontinuity can be produced in a few days. From an experimental and forecasting point of view it would be interesting to obtain these circulations in real time. Unfortunately, the ageostrophic wind is not a measurable quantity and its retrieval from experimental data is difficult, particularly at the mesoscale, since instrumental noise leads to a need for significant data correction. In this context, this paper provides answers to some of the main problems related to the retrieval of ageostrophic winds in frontal systems. It focuses on the feasibility of retrieval while retaining, at small enough scale, details of physical interest. The framework of this study is the future implementation of regular meteorological wind-profiler networks with a sampling time of one hour. This paper proposes to overcome numerous practical problems using an approach based on the variational Analyse du Vent AGeostrophique (AVAG) analysis. Tests of such an approach are done on real data extracted from the Mesoscale Frontal Dynamic Project/FRONTS 87 data base for a typical two-dimensional frontal case (the IOP 7 case). They confirm that the AVAG analysis is able to provide a non-noisy and consistent ageostrophic circulation. Comparisons with classical methods demonstrate the robustness of AVAG and its capability to obtain physically meaningful ageostrophic wind fields. This study also estimates the best and most suitable experimental sampling for practical applications. Sensitivity tests on the quality of the retrieved wind field with respect to (i) the sampling time used, (ii) the availability of additional thermodynamic data and (iii) the geometrical pattern of the network are presented. These tests provide evidence of the importance of accounting for thermodynamical- and dynamical-field along-front variations.

The testing and evaluation of new observing systems (VHF–45MHz, UHF–961 MHz wind profilers) as well as their performance in a network was listed among the goals of the FRONTS87 European field experiment. Using the FRONTS87 dataset for the 12–13 January 1988 cold front, the two horizontal wind components from the INSU-METEO VHF and UHF wind profilers are' quantitatively compared with those derived from collocated special upper-air soundings. Comparison between the sounding and the protilers data shows good agreement with rms differences of 4–4·5 ms-1 for the VHF and 2·2ms-1 for the UHF wind profiler. The combined use of the two profilers with their high timeresolution data (one vertical profile every 15min) along with the high altituderesolution data of the UHF profiler (150m) allowed us to obtain, in precipitation as well as in clear sky areas, a detailed image of both the low-level and upperlevel jet associated with the cold front observed over Brittany France, 12–13 January 1988. The case-study...

A study of the internal dynamics of a low-level jet, its role on the frontal discontinuity evolution, and its relevance to the organization of convection at mesoscale and small scale is presented. The low-level jet studied is associated with an active cold front that was observed during the French—British co-operative field experiment Fronts 87. The originality of the present low-level-jet description lies in the fact that it is observed not only by means of soundings but also by means of a new tool for mesoscale meteorology observations, a wind profiler (stratospheric—tropospheric UHF radar). The high resolution of the wind-profiler data in both time and height allows one to assess, in precipitating as well as in clear-sky areas, a detailed image of the low-level jet and the associated mesoscale and convective-scale circulations. The comparison between observations and predictions of various theories provides information on the physical mechanisms responsible for the initiation and maintenance of the observed mesoscale features. The flow resulting from the presence of the low-level jet produces inertial acceleration and baroclinic symmetric instability which lead to a narrow mesoscale line of sloping motions. Moreover, the interaction of the cold surface outflow with the low-level vertical shear below the jet maximum is found to be crucial in the intensification and maintenance of the observed narrow cold-frontal rainband.

International audience; Advances in e-Infrastructure promise to revolutionize sensing systems and the way in which data are collected and assimilated, and complex water systems are simulated and visualized. According to the EU Infrastructure 2010 work-programme, data and compute infrastructures and their underlying technologies, either oriented to tackle scientific challenges or complex problem solving in engineering, are expected to converge together into the so-called knowledge infrastructures, leading to a more effective research, education and innovation in the next decade and beyond. Grid technology is recognized as a fundamental component of e-Infrastructures. Nevertheless, this emerging paradigm highlights several topics, including data management, algorithm optimization, security, performance (speed, throughput, bandwidth, etc.), and scientific cooperation and collaboration issues that require further examination to fully exploit it and to better inform future research policies. The paper illustrates the results of six different surface and subsurface hydrology applications that have been deployed on the Grid. All the applications aim to answer to strong requirements from the Civil Society at large, relatively to natural and anthropogenic risks. Grid technology has been successfully tested to improve flood prediction, groundwater resources management and Black Sea hydrological survey, by providing large computing resources. It is also shown that Grid technology facilitates e-cooperation among partners by means of services for authentication and authorization, seamless access to distributed data sources, data protection and access right, and standardization.

Gravity wave activity is studied with six years radio sounding data from some of the African meteorological stations located in the 18° N and 05° S latitude domains. This study focuses on gravity wave parameters (e.g., total energy, kinetic and potential energies, fraction of upward propagating energy) above Bamako, Mali (12°53’ N, 07°95’ W). Climatology and seasonal variation are analyzed in the lower stratosphere and upper troposphere. Sources and variability are also examined in relation to convection indices and monsoons.

We provide evidence of the influence of planetary waves on the intensity variations of the 557.7-nm airglow emission. The comparison relies on simultaneous measurements at four different stations located between 37°N and 56°N in latitude, 36°E and 3°W in longitude: meteor wind observations in France and USSR and optical measurements at 557.7 nm in France and Spain, in July 1971. An oscillation of period near 2 days had been identified in the wind data; it is also apparent on the nightglow intensity variations. Its characteristics are well accounted for by the first symmetric mode of the 52- hour period planetary oscillation of horizontal wave number 3, described previously (Glass et al., 1975). A 4±1 hour period gravity wave apparently present in the data of the French stations is discussed.

The stratosphere-troposphere radar PROUST (prototype de radar pour l'observation en UHF de la stratosphere et troposphere) is located at Saint Santin, France (44°39′N; 2°12′E), a place devoted to the French ionospheric incoherent scatter facility whose frequency is 935 MHz. The use of this equipment as stratosphere-troposphere radar has required important modifications of the transmitting and receiving systems, which have been planned in several steps. In a first one, the radar works in a bistatic mode with a 600-m height resolution, allowing measurements in the altitude range 3–10 km. The first results presented here have been obtained with this configuration during two campaigns. In the first one, observations can be interpreted in terms of lee waves; in the second, an intense turbulence activity associated with a high-altitude temperature inversion is observed. In this last case, the oscillations observed in the vertical wind are consistent with trapped gravity waves generated by a decaying turbulence in a stratified medium. In a second step, now operating, a 30-m height resolution has been implemented and will allow a better understanding of these phenomena. In its final version, the PROUST radar will operate in a monostatic mode that will permit to extend the observations up to 15 km.

There are two mechanisms which can account for the oxygen green line emission at 100 km Altitude, namely the Chapman and Barth mechanisms. Theoretical results and experimental data are used in order to discriminate which of these predominates in the atmosphere. In particular we have used an important new test which consists in comparing the phase of the mean diurnal variation of the green line intensity with the phase of the tide responsible for this variation. This is a powerful test because the phase of the green line variation calculated from the tidal phase has a very weak dependence on the atmospheric model used. Our conclusion is that in the atmosphere the Chapman mechanism predominates.

A new hardware decoder-coherent integrator, which will allow a 30 m height resolution with a UHF radar, is described. By using quasi-complementary codes, the decoding is performed in real time before the coherent integration. This device consists of 20 identical PC boards, as many as the number of subpulses in the transmitted pulse, and is able to process simultaneously 20 gates; 40 additions or substractions and memory accesses are performed in 200 ns. This decoder-coherent integrator is very modular and simple in its design, with its 20 identical boards which enhance the overall reliability of the system.

Internal partition functions for the NO molecule have been calculated for the range 100–1000 K at 10 K intervals using a direct summation over all the individual levels involved. Relative populations of the v = 0 level of the fundamental X 2 II state have been deduced. The integrated line absorption cross sections of the γ(1-0) and γ(2-0) bands have been determined for the same range of temperature.

The authors use the Bain Circuit with spontaneous breathing during head surgery (neurosurgery and ophthalmological procedures). Suitable for both adult and pediatric use, it seems to be, due to its unique characteristics, the choice circuit for all anaesthesia procedures in which the physician does not have direct control over the patient's head. Comparative analysis of blood gas levels is effected, on the one hand in children connected to a Digby-Leigh system and Bain Circuit, and on the other hand in adults, some of whom are connected to a two-way system and the other under a filter circuit; all of the patients are then connected to the Bain Circuit. In children the analysis of results shows that for an identical protocol of anaesthesia the quality of spontaneous breathing obtained using the Bain Circuit is the same as that obtained using the Digby-Leigh. In adults anaesthetized using fluothane and with spontaneous breathing, the average level of hypercapnia under filter circuit and Bain Circuit is identical. Also, the same level of alveolar hypoventilation is obtained under spontaneous breathing with the two-way and Bain Circuit systems when there are properly provisioned. Thus this work confirms other studies by showing that the Bain Circuit is particularly well adapted to head surgery because of its low weight and easy manageability. On the other hand, when using spontaneous breathing the level of alveolar hypoventilation, and thus the degree of hypercapnia, is directly related to the level of anaesthesia and independent of the circuit chosen. Only the setting up of controlled breathing would allow the physician to work under the desired level of normo or hypocapnia.

The authors give their experiences in nurseling and children brain neuroradiology anaesthesia. Sodium gammahydroxybutyrate has been definitively adopted after multiples anaesthesial protocoles for the gaz tomoencephalographic exam, known for its technical risks. The gamma OH gives a perfect cardiac and pulmonary stability in difficult conditions, with normal intracranial pression, even in children anaesthesia with Halothane (0.5%) for complementary analgesic effect or with fractionate injections of dextromoramide. Pneumoencephalography has been releguated in second place by the even of brain computer tomography except some particular indications. But this exam qualified as painless is usually indicated in fragile and deficient childrens. Though the intravenous iodated contrasted substance injection can improve the scan image quality and may induce secondary effects at 2 cm3/kg dose. It's again gamma OH after correct premedication that gives stable, perfect immobility, cardiac and pulmonary stability in an ideal anaesthesia for non ventilated patients. The only critical aspect of this method consists on a prolonged and imprevisible delay to awake so that it cannot be an ambulatory anaesthesial method. Therefore it appears that gamma OH in spite of brain computer tomographic event, is an interesting anaesthesic drug but non definitive in brain neuroradiological exam for childrens.

Lafenêtre Henri, Carrère Louis, Petitdidier M., Vollhardt Yves, Quatrefages H. Vaccins anti-brucelliques tués et allergie dans l’espèce ovine. In: Bulletin de l'Académie Vétérinaire de France tome 117 n°4, 1964. pp. 189-191.

Climate-G is a large scale distributed testbed devoted to climate change research. It is an unfunded effort started in 2008 and involving a wide community both in Europe and US. The testbed is an interdisciplinary effort involving partners from several institutions and joining expertise in the field of climate change and computational science. Its main goal is to allow scientists carrying out geographical and cross-institutional data discovery, access, analysis, visualization and sharing of climate data. It represents an attempt to address, in a real environment, challenging data and metadata management issues. This paper presents a complete overview about the Climate-G testbed highlighting the most important results that have been achieved since the beginning of this project.