[hal-00924109] Atmospheric CO2 retrievals from GOSAT TANSO-FTS data

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00443057] Airborne measurements of aerosol optical properties related to early spring transport of mid-latitude sources into the Arctic

Airborne lidar and in-situ measurements of the aerosol properties were conducted between Svalbard Island and Scandinavia in April 2008. Evidence of aerosol transport from Europe and Asia is given. The analysis of the aerosol optical properties based on a multiwavelength lidar (355, 532, 1064 nm) including depolarization at 355 nm aims at distinguishing the role of the different aerosol sources (Siberian wild fires, Eastern Asia and European anthropogenic emissions). Combining, first aircraft measurements, second FLEXPART simulations with a calculation of the PBL air fraction originating from the three different mid-latitude source regions, and third level-2 CALIPSO data products (i.e. backscatter coefficient, depolarisation and color ratio in aerosol layers) along the transport pathways, appears a valuable approach to identify the role of the different aerosol sources even after a transport time larger than 4 days. Above Asia, CALIPSO data indicate more depolarisation (up to 15%) and largest color ratio (>0.5) for the northeastern Asia emissions (i.e. an expected mixture of Asian pollution and dust), while low depolarisation together with smaller and quasi constant color ratio (≈0.3) are observed for the Siberian biomass burning emissions. A similar difference is visible between two layers observed by the aircraft above Scandinavia. The analysis of the time evolution of the aerosol optical properties revealed by CALIPSO between Asia and Scandinavia shows a gradual decrease of the aerosol backscatter, depolarisation ratio and color ratio which suggests the removal of the largest particles in the accumulation mode. A similar study conducted for a European plume has shown aerosol optical properties intermediate between the two Asian sources with color ratio never exceeding 0.4 and moderate depolarisation ratio being always less than 8%, i.e. less aerosol from the accumulation mode.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00750122] On the effect of moisture on the detection of tropospheric turbulence from in situ measurements

The present paper addresses the detection of turbulence based on the Thorpe (1977) method applied to an atmosphere where saturation of water vapor occurs. The detection method proposed by Thorpe relies on the sorting in ascending order of a measured profile of a variable conserved through adiabatic processes, (e.g. potential temperature). For saturated air, the reordering should be applied to a moist-conservative potential temperature, θm, which is analogous to potential temperature for a dry (subsaturated) atmosphere. Here, θm is estimated from the Brunt-Väisälä frequency derived by Lalas and Einaudi (1974) in a saturated atmosphere. The application to balloon data shows that the effective turbulent fraction of the troposphere can dramatically increase when saturation is taken into account. Preliminary results of comparisons with data simultaneously collected from the VHF Middle and Upper atmosphere radar (MUR, Japan) seem to give credence to the proposed approach.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00697491] Hindcast experiments of tropospheric composition during the summer 2010 fires over western Russia

The severe wildfires in western Russia during July-August 2010 coincided with a strong heat wave and led to large emissions of aerosols and trace gases such as carbon monoxide (CO), hydrocarbons and nitrogen oxides into the troposphere. This extreme event is used to evaluate the ability of the global MACC (Monitoring Atmospheric Composition and Climate) atmospheric composition forecasting system to provide analyses of large-scale pollution episodes and to test the respective influence of a priori emission information and data assimilation on the results. Daily 4-day hindcasts were conducted using assimilated aerosol optical depth (AOD), CO, nitrogen dioxide (NO2) and ozone (O3) data from a range of satellite instruments. Daily fire emissions were used from the Global Fire Assimilation System (GFAS) version 1.0, derived from satellite fire radiative power retrievals. The impact of accurate wildfire emissions is dominant on the composition in the boundary layer, whereas the assimilation system influences concentrations throughout the troposphere, reflecting the vertical sensitivity of the satellite instruments. The application of the daily fire emissions reduces the area-average mean bias by 63% (for CO), 60% (O3) and 75% (NO2) during the first 24 h with respect to independent satellite observations, compared to a reference simulation with a multi-annual mean climatology of biomass burning emissions. When initial tracer concentrations are further constrained by data assimilation, biases are reduced by 87, 67 and 90%. The forecast accuracy, quantified by the mean bias up to 96 h lead time, was best for all compounds when using both the GFAS emissions and assimilation. The model simulations suggest an indirect positive impact of O3 and CO assimilation on hindcasts of NO2 via changes in the oxidizing capacity. However, the quality of local hindcasts was strongly dependent on the assumptions made for forecasted fire emissions. This was well visible from a relatively poor forecast accuracy quantified by the root mean square error, as well as the temporal correlation with respect to ground-based CO total column data and AOD. This calls for a more advanced method to forecast fire emissions than the currently adopted persistency approach. The combined analysis of fire radiative power observations, multiple trace gas and aerosol satellite observations, as provided by the MACC system, results in a detailed quantitative description of the impact of major fires on atmospheric composition, and demonstrate the capabilities for the real-time analysis and forecasts of large-scale fire events.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[insu-01021932] Magnetic induction and diffusion mechanisms in a liquid sodium spherical Couette experiment

We present a reconstruction of the mean axisymmetric azimuthal and meridional flows in the DTS liquid sodium experiment. The experimental device sets a spherical Couette flow enclosed between two concentric spherical shells where the inner sphere holds a strong dipolar magnet, which acts as a magnetic propeller when rotated. Measurements of the mean velocity, mean induced magnetic field and mean electric potentials have been acquired inside and outside the fluid for an inner sphere rotation rate of 9 Hz (Rm 28). Using the induction equation to relate all measured quantities to the mean flow, we develop a nonlinear least square inversion procedure to reconstruct a fully coherent solution of the mean velocity field. We also include in our inversion the response of the fluid layer to the non-axisymmetric time-dependent magnetic field that results from deviations of the imposed magnetic field from an axial dipole. The mean azimuthal velocity field we obtain shows super-rotation in an inner region close to the inner sphere where the Lorentz force dominates, which contrasts with an outer geostrophic region governed by the Coriolis force, but where the magnetic torque remains the driver. The meridional circulation is strongly hindered by the presence of both the Lorentz and the Coriolis forces. Nevertheless, it contributes to a significant part of the induced magnetic energy. Our approach sets the scene for evaluating the contribution of velocity and magnetic fluctuations to the mean magnetic field, a key question for dynamo mechanisms.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01084596] Quantum Theory of Helimagnetic Thin Films

We study properties of a helimagnetic thin film with quantum Heisenberg spin model by using the Green's function method. Surface spin configuration is calculated by minimizing the spin interaction energy. It is shown that the angles between spins near the surface are strongly modified with respect to the bulk configuration. Taking into account this surface spin reconstruction, we calculate self-consistently the spin-wave spectrum and the layer magnetizations as functions of temperature up to the disordered phase. The spin-wave spectrum shows the existence of a surface-localized branch which causes a low surface magnetization. We show that quantum fluctuations give rise to a crossover between the surface magnetization and interior-layer magnetizations at low temperatures. We calculate the transition temperature and show that it depends strongly on the helical angle. Results are in agreement with existing experimental observations on the stability of helical structure in thin films and on the insensitivity of the transition temperature with the film thickness. We also study effects of various parameters such as surface exchange and anisotropy interactions. Monte Carlo simulations for the classical spin model are also carried out for comparison with the quantum theoretical result.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[tel-00831642] Étude de la coalescence et du mûrissement dans les mousses liquides : des expériences modèles à différentes échelles.

Liquid foams are widely used in industry and in everyday life. However, their stability is not fully understood or fully controlled, their formulation being essentially empirical. It is therefore difficult to predict the ability of a surfactant solution to generate foam and to control their destabilization. This thesis proposes simple experiments that rely on the multi-scale nature of foams in order to attempt to establish clear links between physical chemistry and stability.First of all, we revisited an experiment of liquid films entrainment to illustrate the stability of foam films during generation or rearrangement (T1 process). We have shown the existence of two regimes: (i) a unconfined regime, for which the stability of films is reduced and depends on physical chemistry and (ii) a confined regime for which the role of physical chemistry stability is limited and is mainly controlled by hydrodynamics.Secondly, we investigated the influence of physical chemical and liquid fraction on the competition between coalescence and coarsening thanks to the study of a single layer of bubbles (2D foam). We propose a method for in situ measurement of the permeability of films by simple and fast study of the transient regime of coarsening in 2D foam. We observed a correlation between diffusion coefficient of gas and permeability.Finally we describe the results of a space experiment on wet foam aging at large times (volume liquid fraction higher than 30%), extremely difficult on Earth because of gravity drainage, and to which we participated.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[tel-00831642] Étude de la coalescence et du mûrissement dans les mousses liquides : des expériences modèles à différentes échelles

Liquid foams are widely used in industry and in everyday life. However, their stability is not fully understood or fully controlled, their formulation being essentially empirical. It is therefore difficult to predict the ability of a surfactant solution to generate foam and to control their destabilization. This thesis proposes simple experiments that rely on the multi-scale nature of foams in order to attempt to establish clear links between physical chemistry and stability.First of all, we revisited an experiment of liquid films entrainment to illustrate the stability of foam films during generation or rearrangement (T1 process). We have shown the existence of two regimes: (i) a unconfined regime, for which the stability of films is reduced and depends on physical chemistry and (ii) a confined regime for which the role of physical chemistry stability is limited and is mainly controlled by hydrodynamics.Secondly, we investigated the influence of physical chemical and liquid fraction on the competition between coalescence and coarsening thanks to the study of a single layer of bubbles (2D foam). We propose a method for in situ measurement of the permeability of films by simple and fast study of the transient regime of coarsening in 2D foam. We observed a correlation between diffusion coefficient of gas and permeability.Finally we describe the results of a space experiment on wet foam aging at large times (volume liquid fraction higher than 30%), extremely difficult on Earth because of gravity drainage, and to which we participated.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[tel-00809290] Quantum transport of ultracold atoms in disordered potentials

In this thesis we study the quantum transport of matter waves with ultracold atoms. Such ultracold atom systems provide a very good control and a high flexibility of the parameters of the systems like the interactions, its dimensionality and the external potentials. This makes them a great tool for the investigation of several fundamental concepts of condensed matter physics. We focus on the quantum transport in disordered media. It differs to classical transport by the fundamental role played by inference phenomena, which can eventually lead to the suppression of transport; known as Anderson Localization. Observing the expansion of a Bose-Einstein condensate in a strong light disorder, we show evidence for Localization of ultracold atoms in three dimensions. In the last part of this manuscript we discuss the observation of Coherent Backscattering of ultracold atoms, which is a direct signal of the role of quantum coherence in quantum transport in disordered media. We observe the time evolution of the momentum distribution of a cloud of ultra-cold atoms, launched with a narrow velocity distribution in a disordered potential. A peak emerges in the backwards direction, corresponding to the CBS signal.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[tel-00809290] Quantum transport of ultracold atoms in disordered potentials

In this thesis we study the quantum transport of matter waves with ultracold atoms. Such ultracold atom systems provide a very good control and a high flexibility of the parameters of the systems like the interactions, its dimensionality and the external potentials. This makes them a great tool for the investigation of several fundamental concepts of condensed matter physics. We focus on the quantum transport in disordered media. It differs to classical transport by the fundamental role played by inference phenomena, which can eventually lead to the suppression of transport; known as Anderson Localization. Observing the expansion of a Bose-Einstein condensate in a strong light disorder, we show evidence for Localization of ultracold atoms in three dimensions. In the last part of this manuscript we discuss the observation of Coherent Backscattering of ultracold atoms, which is a direct signal of the role of quantum coherence in quantum transport in disordered media. We observe the time evolution of the momentum distribution of a cloud of ultra-cold atoms, launched with a narrow velocity distribution in a disordered potential. A peak emerges in the backwards direction, corresponding to the CBS signal.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01063795] Sensitivity analysis of complex models: coping with dynamic and static inputs

In this paper, we address the issue of performing sensitivity analysis of complex models presenting uncertain static and dynamic inputs. The dynamic inputs are viewed as random processes which can be represented by a linear combination of the deterministic functions depending on time whose coefficients are uncorrelated random variables. To achieve this, the Karhunen-Loève decomposition of the dynamic inputs is performed. For sensitivity analysis purposes, the influence of the dynamic inputs onto the model response is then given by the one of the uncorrelated random coefficients of the Karhunen-Loève decomposition, which is the originality here. The approach is applied to a building energy model, in order to assess the impact of the uncertainties of the material properties and the weather data on the energy performance of a real low energy consumption house.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01088995] A 2D reconstruction for the transverse coupling of shallow water models

This work is dedicated to the modeling of exchanges between a river and its surrounding floodplains during floods overflowing its bed. Modeling flows in each subdomain, that of the river and that of the floodplain, has been the subject of numerous works for over 50 years and is now well understood. A coupling strategy is considered in order to preserve the advantages of 1D and 2D models in their respective subdomains. In comparison with other transverse coupling strategies already presented in the literature, we introduce a direct method, without overlapping the models or introducing numerical parameters. This strategy is based on the resolution of the Riemann 2D problem at the coupling interface (the bank) and requires the estimation of the transverse velocity close to the interface. We propose a model of transverse velocity using successive resolutions of Riemann problems. Then, we present a numerical resolution of the coupling system, based on a finite volume method for any Riemann solvers. Particular attention was given to the essential properties of the model (conservation of mass, positivity of water depth, and well-balanced scheme). Lastly, the precision and efficiency of the method are illustrated using examples of simulations.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00840190] Sur la mesure d'une force suiveuse mobile fléchissant une lame en grands déplacements

On s'intéresse à la force exercée par un patin mobile en translation fléchissant une lame élastique encastrée à une extrémité. Le contact étant supposé obéir à une loi de frottement de Coulomb, la force est suiveuse et la forme de la lame est donnée par l'elastica via une transformation homothétique dont le facteur d'échelle est donné par la valeur de la force. Après avoir rappelé la modélisation de ce problème non linéaire, nous verrons comment accéder expérimentalement à la raideur en flexion et au coefficient de frottement à partir de la mesure de la force et du déplacement du patin. Outre la généralité de la situation, ce problème rentre dans le cadre de la caractérisation de surfaces textiles pileuses dont les propriétés mécaniques sont difficilement accessibles étant donnés les matériaux et les échelles considérés.



from HAL : Dernières publications https://hal-upec-upem.archives-ouvertes.fr/hal-00840190

[hal-00840190] Sur la mesure d'une force suiveuse mobile fléchissant une lame en grands déplacements

On s'intéresse à la force exercée par un patin mobile en translation fléchissant une lame élastique encastrée à une extrémité. Le contact étant supposé obéir à une loi de frottement de Coulomb, la force est suiveuse et la forme de la lame est donnée par l'elastica via une transformation homothétique dont le facteur d'échelle est donné par la valeur de la force. Après avoir rappelé la modélisation de ce problème non linéaire, nous verrons comment accéder expérimentalement à la raideur en flexion et au coefficient de frottement à partir de la mesure de la force et du déplacement du patin. Outre la généralité de la situation, ce problème rentre dans le cadre de la caractérisation de surfaces textiles pileuses dont les propriétés mécaniques sont difficilement accessibles étant donnés les matériaux et les échelles considérés.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00796341] Lower tropospheric ozone at northern midlatitudes: Changing seasonal cycle

At northern mid-latitudes the abundance of tropospheric O3 has increased by a factor of approximately 2 since the 1950s. The cause of this increase is generally attributed to increasing anthropogenic precursor emissions, but present chemical and transport models cannot quantitatively reproduce its magnitude. Here we show another manifestation of changes in O3 abundance - a shift of the seasonal cycle at northern mid-latitudes so that the observed peak concentrations now appear earlier in the year than in previous decades. The rate of this shift has been 3 to 6 days per decade since the 1970s. We examine possible reasons to explain this shift and suggest it is due to changes in atmospheric transport patterns combined with spatial and temporal changes in emissions. Detailed modeling is necessary to test these hypotheses; this investigation will provide useful guidance for improving global chemistry-climate models as well as stringent tests of the model results.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00778597] Year-round retrievals of trace gases in the Arctic using the Extended-range Atmospheric Emitted Radiance Interferometer

The Extended-range Atmospheric Emitted Radiance Interferometer (E-AERI) was installed at the Polar Environment Atmospheric Research Laboratory (PEARL) at Eureka, Nunavut, Canada in October 2008. Spectra from the E-AERI provide information about the radiative balance and budgets of trace gases in the Canadian high Arctic. Measurements are taken every seven minutes year-round, including polar night when the solar-viewing spectrometers at PEARL are not operated. This allows E-AERI measurements to fill the gap in the PEARL dataset during the four months of polar night. Measurements were taken year-round in 2008-2009 at the PEARL Ridge Lab, which is 610 m above sea-level, and from 2011-onwards at the Zero-Altitude PEARL Auxiliary Lab (0PAL), which is 15 km from the Ridge Lab at sea level. Total columns of O3, CO, CH4, and N2O have been retrieved using a modified version of the SFIT2 retrieval algorithm adapted for emission spectra. This provides the first nighttime measurements of these species at Eureka. Changes in the total columns driven by photochemistry and dynamics are observed. Analyses of E-AERI retrievals indicate accurate spectral fits (root-mean-square residuals < 1.5%) and a 10-15% uncertainty in the total column, depending on the trace gas. O3 comparisons between the E-AERI and a Bruker IFS 125HR Fourier transform infrared (FTIR) spectrometer, three Brewer spectrophotometers, two UV-visible ground-based spectrometers, and a System D'Analyse par Observations Zenithales (SAOZ) at PEARL are made from 2008-2009 and for 2011. 125HR CO, CH4, and N2O columns are also compared with the E-AERI measurements. Mean relative differences between the E-AERI and the other spectrometers are 1-14% (depending on the gas), which are less than the E-AERI's total column uncertainties. The E-AERI O3 and CO measurements are well correlated with the other spectrometers; the best correlation is with the 125HR (r > 0.92). The 24-h diurnal cycle and 365-day seasonal cycle of CO are observed and their amplitudes are quantified by the E-AERI (6-12% and 46%, respectively). The seasonal variability of H2O has an impact on the retrievals, leading to larger uncertainties in the summer months. Despite increased water vapour at the lower-altitude site 0PAL, measurements at 0PAL are consistent with measurements at PEARL.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00808110] Arctic ozone loss in Siberia in 2011 and 2012

The atmospheric ozone plays an important role in understanding of the processes occurring in the atmosphere and changes in the climate. Total ozone observations in Siberia were performed by Brewer MKIV No. 049 spectrophotometer in Tomsk, Western Siberia and SAOZ UV-Vis spectrometers deployed along the Arctic Circle in Salekhard aerological station since 1998 and Zhigansk aerological station in Eastern Siberia since 1991. We also use 2Z-ECC ozonesondes for ozone profile observations in winter-spring period at the Salekhard aerological station at the in Western Siberia and ECC-6A sondes at the drifting North Pole station NP-38 in the Central Arctic area. During the winter-spring season in 2011, Arctic ozone in the 19-21 km altitude region was observed to be more than 70% less that typical values. In the winter-spring of 2012, on the other hand, Arctic conditions were overall much warmer than in 2011, and no evidence of significant ozone loss was seen above the Asiatic regions of Russian Federation. The aim of the paper is to describe which and where these measurements were carried out and illustrate their performances by some examples of ozone data measured in Western and Eastern Siberia, Russia such as that which occurred in the winter-spring season of 2011.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00817093] Vertical and horizontal transport of water vapour and aerosol in the tropical stratosphere from high-resolution balloon-borne observations. (poster)

We present the results of accurate balloon-borne observations of water vapor and aerosol obtained during a field campaign held in March 2012 in Bauru, Brazil (22.3 S) in the frame of a TRO-pico project. The aim of the TRO-pico project, supported by the French ANR, is to characterize the variability and frequency of water convective injections, their contribution at the regional wet season timescale, and to improve the understanding of their role with respect to the cold trap at a wider scale. The balloon payloads flown during the campaign included Pico-SDLA IR laser hygrometers, FLASH-B fluorescence Lyman-alpha hygrometers, COBALD aerosol backscatter sondes and several other instruments for the measurement of gas-phase and particle constituents. A S-band radar operating on the site provided the information on cloud tops. The series of vertical profiles obtained show well correlated enhancements in water vapor and aerosol in the lowermost stratosphere at 430 K in some of the soundings. Trajectory analysis links these features to horizontal transport from Southern Hemisphere extra-tropical stratosphere. Another sounding performed on a convectively active day revealed water vapor enhancements above the cold point tropopause at 385 and 400 K without coincident aerosol enhancements. These are unambiguously associated with local convective overshoots as shown by an overshoot tracking analysis making use of backward trajectories and a sequence of echo tops radar images of echo tops. The relative contributions of long-range horizontal and local vertical transport on the stratospheric composition will be discussed.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00817128] Evidence of much more intense land convection in the Southern than in the Northern tropics and tentative explanation. (poster)

Convective overshooting over tropical land areas is a key contributor to troposphere-to-stratosphere exchange, shown to inject in the lower stratosphere adiabatically cooled air (Pommereau and Held 2007, Cairo et al., 2011, Khaykin et al., 2012,), trace and chemically active gases (Ricaud et al., 2007, 2010), ice crystals (Corti et al., 2007, Nielsen et al., 2007, Khaykin et al., 2009) and tropospheric clean air diluting the aerosols (Vernier et al., 2011). However, the altitude reached by those events differs dramatically between the hemispheres. Convective overshootings are observed to reach 20-21 km over the southern tropical continents, whereas in the Northern they are limited to altitude below the tropopause. Convection appears much more intense in the South. The suggested explanation for that is the higher albedo and the larger anthropogenic and desert dust tropospheric aerosols AOD of the northern tropical continents limiting the solar heating and thus the daytime increase of Convective Available Potential Energy (CAPE), compared to the low albedo and clean rain forest areas of the southern tropics. Shown in the presentation will be the experimental evidence from the various observations of the difference of convection intensity between the two hemispheres, the tentative explanation of this feature by the influence of aerosols AOD and albedo on CAPE, and brief conclusions regarding the impact of the difference on the composition of the stratosphere and climate modeling.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00822038] Seasonal variation of NO2 and O3 VCD at Río Gallegos, Argentine, using portable zenith-sky DOAS

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00821957] Ozone depletion at temperature warmer than TNAT in the Arctic. (poster)

The unprecedented ozone destruction in the Arctic vortex in 2011 that extended until the end of March offers a unique opportunity for testing the relationship between temperature, responsible for heterogeneous chlorine activation on PSCs and aerosols and the amplitude of ozone loss. Indeed, as shown by the total ozone evolution in the vortex during that winter from the SAOZ network compared to passive ozone simulations from the REPROBUS CTM, most of the total 39% total ozone depletion occurred after mid-February at a rate of near 0.8% /day when relatively low temperatures were still present in the Arctic. The evolution of ozone depletion is shown to fully match that of the cumulative area of temperatures below the chlorine activation threshold weighted by vortex sunlight illumination, assuming, as shown by Drlda and Mueller (2010), that chlorine activation occurs at 195 K at the 475 K level. However, if instead, the total integrated backscatter for combined liquid aerosols/PSCs inside the vortex reported by CALIPSO or the cumulated PSC surface at 191 K aligned to STS threshold are used, PSCs are seen to disappear in early March, that is three weeks before the end of ozone depletion. The suggestion is thus that chlorine activation takes place at temperature significantly warmer than that of NAT or STS PSC formation, on binary aerosol, still present and accounted for in the integrated backscatter, but of smaller surface area. The same analyses applied to all past winters since 1994 confirms the ozone depletion at relatively warm temperature in the absence of PSC. The mechanism involved is explored by a variety of model simulations, including or not, liquid binary aerosols, NAT and STS.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00989750] Tidal effects on stratospheric temperature series derived from successive Advanced Microwave Sounding Units

Stratospheric temperature series derived from the Advanced Microvave Sounding Unit on board successive NOAA satellites reveal during periods of overlap some bias and drifts. Part of the reason for these discrepancies could be associated with atmospheric tides as the orbits of these satellites drifted, inducing large changes in the actual time of measurements. NOAA 15 and 16, which exhibit a long period of overlap, allow deriving diurnal tides that can correct such temperature drifts. The characteristics of the derived diurnal tides during summer periods is in good agreement with those calculated with the Global Scale Wave model, indicating that most of the observed drifts is likely due to the atmospheric tides. Cooling can be biased by a factor of 2, if time of measurements are not considered. When diurnal tides are considered trends derived with temperature lidar series are in good agreement with AMSU series. Future adjustments of temperature time series based on successive AMSU instruments will require to consider corrections associated with the local time of measurements.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00808439] Particles in the tropical UTLS from CALIPSO lidar measurements

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01073965] Water vapor observations up to the lower stratosphere through the Raman lidar during the MAïdo LIdar Calibration Campaign

A new lidar system devoted to tropospheric and lower stratospheric water vapor measurements has been installed at the Maïdo altitude station facility of La Reunion Island, in the southern subtropics. The main objectives of the MAïdo LIdar Calibration Campaign (MALICCA), performed in April 2013, were to validate the system, to set up a calibration methodology, to compare the acquired water profiles with radiosonde measurements and to evaluate its performances and capabilities with a particular focus on the UTLS measurements. Varying the characteristics of the transmitter and the receiver components, different system configuration scenarios were tested and possible parasite signals (fluorescent contamination, rejection) were investigated. A hybrid calibration methodology has been set up and validated to insure optimal lidar calibration stability with time. In particular, the receiver transmittance is monitored through the calibration lamp method that, at the moment, can detect transmittance variations greater than 10-15%. Calibration coefficients are then calculated through the hourly values of IWV provided by the co-located GPS. The comparison between the constants derived by GPS and Vaisala RS92 radiosondes launched at Maïdo during MALICCA, points out an acceptable agreement in terms of accuracy of the mean calibration value (with a difference of approximately 2-3%), but a significant difference in terms of variability (14 vs. 7-9%, for GPS and RS92 calibration procedures, respectively). We obtained a relatively good agreement between the lidar measurements and 15 co-located and simultaneous RS92 radiosondes. A relative difference below 10% is measured in low and middle troposphere (2-10 km). The upper troposphere (up to 15 km) is characterized by a larger spread (approximately 20%), because of the increasing distance between the two sensors. To measure water vapor in the UTLS region, nighttime and monthly water vapor profiles are presented and compared. The good agreement between the lidar monthly profile and the mean WVMR profile measured by satellite MLS has been used as a quality control procedure of the lidar product, attesting the absence of significant wet biases and validating the calibration procedure. Thanks to its performance and location, the MAIDO H2O lidar is devoted to become a reference instrument in the southern subtropics, allowing to insure the long-term survey of the vertical distribution of water vapor, and to document scientific themes such as stratosphere-troposphere exchange, tropospheric dynamics in the subtropics, links between cirrus clouds and water vapor.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00732464] Temperature of Polar Stratospheric Clouds formation in the Arctic and Antarctic

Polar Stratospheric Clouds (PSCs) induce a remarkable reddenings of the sky at twilight. Such reddening has been observed regularly by the SAOZ UV-visible spectrometers operating in polar regions in Dumont d'Urville in Antarctica and Sodankyla in Finland. The PSC detection is based on a Color Index (CI) derived from the ratio of sunlight scattered at zenith at 550 to 350 nm. The cloud altitude is retrieved from the SZA (Sun Zenith Angle) of maximum CI, after calibration by comparison with PSCs altitude observed by the CALIPSO lidar in orbit since 2006, a ground-based lidar in Dumont d'Urville and backscatter sondes balloon flights in Sodankyla. The temperature threshold at which PSCs can form is then investigated using the ECMWF model at the cloud level. Shown will be the statistics based on more than 20 years of observations in Sodankyla in Finland and in Dumont d'Urville in Antarctica. The PSC threshold temperature is found to be lower by about 5K in the Antarctic than in the Arctic, which is consistent with the expected stronger de-nitrification and dehydration of the southern winter vortex compared to the northern.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00732514] Long-term evolution of tropical stratospheric O3 and NO2 Columns

The tropical region is the main entry point of the chemical species in the troposphere lifted and transported by convection in the stratosphere through the tropopause and redistributed to higher latitudes via the Brewer Dobson circulation. Thus any change in the distribution of stratospheric constituents in the tropics will have an impact on their concentration at mid-latitudes. Long time series of O3 and NO2 columns in the tropics are available from 2 SAOZ UV-visible spectrometers stations: in Bauru (Brazil, 22°S, 49°W) since 1995 and in La Réunion (21°S, 55°E) in the Indian Ocean since 1993. The most significant modulation for both components at both stations is the seasonal cycle (~40%). A multiple regression analysis of ozone and NO2 columns at Bauru and la Reunion has quantified the impact of solar and geophysical parameters of their variability. Following this analysis, the cycles of the most influential parameters in the tropics are (in decreasing order): the Quasi-Biennal Oscillation (QBO) with 40 % for both species, the El-Niño Southern Oscillation (ENSO) with 25% for O3 and 20% for the NO2, the solar flux with 15% and 18%, and finally the stratospheric aerosols with 20% and 12%. After subtracting these influences, the long-term residual variations of ozone are not significant. In contrast, NO2 shows a significant increase at both stations between 2001-2006, followed by a decrease after 2007. Same analysis has been applied to a merged satellite data set above the stations with GOME (1995-2002) - SCIAMACHY (2003-2011) for NO2 columns and EPTOMS (1995-2004) - OMI TOMS (2005-2011) for O3 columns. The long-term residual variations of those data present similar behaviour as SAOZ. From variations of the Eddy heat flux, variations in average intensity of meridional exchange through the southern subtropical barrier related to the amplitude of planetary waves over the entire Southern Hemisphere have been identified since 2001. These distortions of amplitude of planetary waves, affecting all longitudes, have been detected through the modulation of the two tropical stations's equivalent latitude. After taking into account this influence, the NO2 residual trend in the tropics is shown to be of 3%/decade only, that is consistent with the known increase by 2.5%/decade, of N2O the source of nitrogen oxides in the stratosphere.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00732567] Observation of solar UV radiation and total ozone column using ground based instruments in Rio Gallegos, Argentina (51°36'S, 69°19'W). (poster)

As a part of environmental studies in the southern hemisphere, the CEILAP (UNIDEF-MINDEF) Lidar Division with the financial support of JICA (Japan International Cooperation Agency) and the collaboration of LATMOS, France mounted a ground based remote sensing site at Río Gallegos city (51º 36'S, 69º 19'W), at southern part of Argentina. The site called Atmospheric Observatory of Southern Patagonia (OAPA) has carried out systematic measurements of stratospheric ozone with lidar remote sensing techniques and passive sensors to measure solar UV irradiance from 2005. The Patagonian region is affected each spring season by the polar vortex which produces depletion in the total ozone column increasing the UV radiation that reaches the surface. In this work we report the results of total ozone column and UV radiation from different passive instruments as SAOZ and multichannel GUV-541 radiometer. A correlation between both instruments has been established to Río Gallegos in the period 2005-2011. Also we have taken into account the cloud cover that produces strong impact in the the amount of the UV radiation that reach the ground surface. We reported different cases of study where the OAPA site was inside of polar vortex.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00734081] Evaluation of Satellite Total Ozone and NO2 Columns Using the SAOZ UV-Vis Network

The full series of SAOZ network total ozone measurements in the visible Chappuis bands has been revised according to the spectral analysis and Air Mass Factor (AMF) settings recommended by the NDACC UV-Vis Working Group (Hendrick et al., 2011). They have been compared to overpass observations from the TOMS, GOME-GDP4, SCIAMACHY-TOSOMI, SCIAMACHY-OL3, OMI-TOMS, and OMI-DOAS satellite instruments. Significant improvement is obtained after applying the new O3 AMFs, although systematic seasonal differences between SAOZ and all other instruments still remain. These are shown to originate from (i) a stratospheric temperature and solar zenith angle (SZA) dependencies in the satellites retrievals, (ii) longitudinal modulations and seasonal variations of tropospheric ozone columns not accounted for in the TOMS V8 ozone profile climatology used for calculating the AMFs, and (iii) uncertainties on the climatological stratospheric ozone profiles for polar winter conditions. For those measurements mostly sensitive to stratospheric temperature like TOMS, OMI-TOMS or to SZA like SCIAMACHY-TOSOMI, the application of temperature and SZA corrections results in the almost complete removal of the seasonal difference with SAOZ, improving significantly the consistency between satellite and ground-based total ozone series. However, small but sometimes significant biases remain after applying those corrections. A similar exercise is in progress with SAOZ NO2 data sets, using AMFs calculated from a profile climatology based on HALOE, SAGE II, POAM III and SAOZ balloon profiles. The consistency with GOME/ERS2, SCIAMACHY/ENVISAT and OMI/AURA NO2 total columns is also currently 5 examined. In this presentation, we will focus on the resulting evaluation of ozone and NO2 total columns biases of the various satellite instruments.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00739026] Local To Global Distributions of Atmospheric Ammonia. (poster)

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00439408] First global ammonia distributions from infrared satellite observations

Infrared sounding of our atmosphere is at present confined to a number of species with lifetimes of several weeks to years. Short lived species are mainly confined to the boundary layer, close to their emission sources and for a long time it has been assumed that infrared instruments are not well suited for monitoring them. Yet, satellite monitoring of such species is highly desirable, as ground based measurements are sparse and are unable to map the regional and seasonal variability. Ammonia is one of the most important short lived species in our atmosphere, being the principal alkaline component and a large contributor to reactive nitrogen. In the last century global ammonia emissions have doubled and are expected to increase further in the coming decades, with huge implications on the Earth's biogeochemistry, environment and climate. The ammonia budget is poorly understood and accounts for the largest uncertainty in the global nitrogen cycle. Ammonia has been observed in the last years with infrared sounders locally and for the first time with IASI in biomass burning plumes. In this talk we present the first global ammonia concentrations from space based observations. Concentrations are retrieved using the infrared spectra of the space-borne sounder IASI onboard the MetOp-A platform. We present the 2008 global yearly average and identify a multitude of hotspots, notably over biomass burning regions and agricultural areas. Next we compare the measured concentrations with the concentrations from a global chemistry model, and draw robust conclusions on underestimates in the model in large parts of North-America, Europe and Asia. IASI provides daily global coverage with a high spatial resolution and is therefore ideal in monitoring the spatio-temporal variability of ammonia. As a test case, we analyse in detail the seasonal and geographical variations of ammonia in the San Joaquin Valley, California, for which we also present measurements from the AIRS sounder.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00485499] Global and local ozone measurements from the thermal infrared IASI sounder for the monitoring of atmospheric composition

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01005169] TIR retrievals of CO2, N2O and CH4 over the Arctic ocean from TANSO-FTS and comparison with IASI

The TANSO-FTS thermal infrared (TIR) spectra of GOSAT in band B4 are quite interesting to provide additional atmospheric information on what is available from the SWIR (B3 and B2) and NIR bands (B1). In this presentation the retrieval scheme based on the LARA radiative transfer and inversion algorithm will be presented for the determination of XCO2, XN2O and XCH4 from spectra recorded over the Arctic ocean during summer. This choice was made to characterize the TANSO-FTS performances in rather difficult conditions (large solar zenith angle (SZA) and cold surface), pushing the performances of TIR sounders to the limit. It also allows us to compare the performances of TANSO-FTS (high spectral resolution for the nominal L1B product of ~ 0.25 cm-1) with those of the lesser resolved Fourier transform space instrument IASI (L1C product of ~ 0.5 cm-1 resolution), which has a better noise figure. Comparisons of the two sounders are possible at high latitude where simultaneous off-nadir observations (SONO) are possible. Comparisons of the expected theoretical performances will be presented together with the actual performances on nearly coinciding SONO footprints (or IFOVs) of the two TIR sounders over water. The IFOVs where carefully filtered for clouds and the choice of Arctic ocean observations is reducing the uncertainties related to IFOV homogeneity. The retrieved surface temperatures Tsurf is used as a common diagnostic and is also compared to the L2 Eumetsat IASI product. A progress report on the issues related to the knowledge of the TANSO-FTS noise and instrument line shape (ILS) as well as spectroscopic issues with line-by-line parameters or heavy molecule cross-sections will be presented. Results will be presented for 2010 (the period of the SCORE-MIP exercises) and possibly for 2013 (to demonstrate that trends are indeed detectable with TANSO-FTS on GOSAT).



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01088959] Helium clusters doped with electronically excited alkali metal atoms

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00439440] Monitoring of atmospheric composition using the thermal infrared IASI sounder

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00485500] Using IASI trace gas retrievals to analyze the impact of fire emissions on air quality

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01088957] Temperature dependence of sodium and ionized calcium resonance lines perturbed by helium

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00672737] Thin films of SmFeO3 on quartz substrate modelled as anisotropic optical material. (poster)

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00671761] Spectroscopie IR de molécules piégées en matrices à la fois du point de vue expérimental et de l'analyse des résultats expérimentaux par modélisation et simulation

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00673356] Caractérisation d'un système fritté de nanoparticules d'argent par Analyses Spectroscopiques Complémentaire. (poster)

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00672545] Reliabilty of Mechatronic systems from analysis by MEB and SE spectroscopy

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00672519] Modelling optical ellipsometric parameters perovskite oxides thin films deposited by pulsed laser

N/A



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00921248] Towards IASI-New Generation (IASI-NG): impact of improved spectral resolution and radiometric noise on the retrieval of thermodynamic, chemistry and climate variables

Besides their strong contribution to weather forecast improvement through data assimilation, thermal infrared sounders onboard polar-orbiting platforms are now playing a key role for monitoring atmospheric composition changes. The Infrared Atmospheric Sounding Interferometer (IASI) instrument developed by the French space agency (CNES) and launched by Eumetsat onboard the Metop satellite series is providing essential inputs for weather forecasting and pollution/climate monitoring owing to its smart combination of large horizontal swath, good spectral resolution and high radiometric performance. EUMETSAT is currently preparing the next polar-orbiting program (EPS-SG) with the Metop-SG satellite series that should be launched around 2020. In this framework, CNES is studying the concept of a new instrument, the IASI-New Generation (IASI-NG), characterized by an improvement of both spectral and radiometric characteristics as compared to IASI, with three objectives: (i) continuity of the IASI/Metop series; (ii) improvement of vertical resolution; (iii) improvement of the accuracy and detection threshold for atmospheric and surface components. In this paper, we show that an improvement of spectral resolution and radiometric noise fulfill these objectives by leading to (i) a better vertical coverage in the lower part of the troposphere, thanks to the increase in spectral resolution; (ii) an increase in the accuracy of the retrieval of several thermodynamic, climate and chemistry variables, thanks to the improved signal-to-noise ratio as well as less interferences between the signatures of the absorbing species in the measured radiances. The detection limit of several atmospheric species is also improved. We conclude that IASI-NG has the potential for strongly benefiting the numerical weather prediction, chemistry and climate communities now connected through the European GMES/Copernicus initiative.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00638646] High resolution assimilation of IASI ozone data with a global CTM

The pixel size of the Infrared Atmospheric Sounding Interferometer (IASI) remote sensor is much smaller than the horizontal grid size of current Chemical Transport Models (CTMs). In order to assimilate the maximum of information from the IASI retrievals, we have increased the horizontal resolution of our model MOCAGE to be consistent with the IASI pixel size. Experiments are carried out with the Valentina data assimilation system using the standard and the high resolution versions of the model. Two resolutions of the horizontal Gaussian grid have been used for the model: with a T42 and a T170 triangular truncations. Our study is based on the combination of data from the IASI instrument and from the Microwave Limb Sounder (MLS), since this latter dataset allows the information to be spread through the whole atmospheric columns at a low computational cost. Two datasets of ozone super-observations have been constructed by averaging the IASI data on the two model grids. Direct model simulations without data assimilation first show that the increase of the horizontal resolution modifies the ozone smallest scale structures as well as the ozone meridional distribution. This modification results from a better representation of the vertical velocity with the T170 configuration. When the ozone assimilation is performed there is less influence of the horizontal resolution of the model. Nevertheless, in a general way, comparisons with independent data show large reductions of the ozone standard deviations when the resolution is increased. When the ozone assimilation is performed with the high resolution dataset, the high resolution model does not improve the ozone analysis compared to the one obtained with the same model resolution but with the low resolution IASI dataset. This result is due to the difficulty to combine IASI data and MLS data. For assimilating IASI data at high resolution the horizontal correlation length-scale has to be decreased to catch the small scale structures present in the dataset. By doing so the influence of the coarser resolution MLS data is decreased and part of the information brought on the vertical shape of the ozone profile is lost. It is concluded that it is essential to add information on the vertical distribution of ozone column when the IASI data is assimilated at a resolution close to the pixel size. Using IASI averaging kernels would likely improve the simulations, but the computational cost would be much higher. Alternatively, better results might be obtained by a careful tuning of the horizontal correlation length-scale.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00546155] Validation of IASI Ozone profiles using balloon sounding data

Here we present a validation of IASI vertical ozone profiles. This has been done using balloon ozonesonde data, which have a vertical resolution of about 100 m and measures ozone from the surface up to an altitude of about 30 km. IASI vertical ozone profiles are given as partial ozone columns [in DU per layer] between varying pressure levels. To validate the satellite derived ozone layers with the balloon ozone sounding data we integrate the ozone measured by the balloon ozone soundings between the corresponding IASI pressure levels. We take into account the IASI averaging kernels in our analysis in order to smooth the ozonesonde data towards the resolution of the satellite data.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00614632] Using Thermal Infrared Absorption and Emission to Determine Trace Gases

The light emerging from the top of the atmosphere in the greater part of the infrared region is thermal radiation from the Earth's surface. The resultant spectra obtained depend on the temperature difference between the emitting feature and absorbing gas. In this region the greenhouse gases, carbon dioxide, CO2, methane, CH4, ozone, O3, and water, H2O, are observed as well as carbon monoxide, CO, a product indicative of fossil fuel combustion, methanol, CH3OH, from biomass burning, and ammonia, NH3, from agriclulture. Chapter 3 describes the techniques for retrieving atmospheric abundances of these and other species from a number of satellite instruments, and concludes with suggestions for future developments.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01005478] IASI METOP L1C analyses for methane and carbone dioxide over 5 years

During the last decade, remote sensing sounders have demonstrated their capability for monitoring atmospheric composition and pollution. The Infrared Atmospheric Sounding Interferometer (IASI) instrument delivers more than 1.3x106 spectra per day and provides global coverage twice a day. It is characterized by an apodized resolution of 0.5 cm-1 and a low radiometric noise. Concentrations and seasonal patterns for several atmospheric key species are routinely retrieved from the IASI spectra using inverse methods. Such processes rely on both observations and an a priori, which can lead to errors in the geophysical retrievals. Retrieving carbon dioxide (CO2) or methane (CH4) is challenging due to the sensitivity of infrared channels to both temperature and concentration variations. In addition, spectroscopic broadening effects (for example line-mixing) specific to these molecules add more complexity in the retrieval process. In this work we investigate the temporal variations of some atmospheric species by using only the L1C radiances. This method avoids the simulation of the complex spectroscopic effects and provides a new process to analyze the IASI dataset. Only the clear sky scenes are taken into account in this work. Clear sky scene are discriminated from cloudy scenes using the IASI L2 products. This work discusses the L1C radiances analysis for 5 complete years of IASI observations from January 2008 to December 2012, in CH4 and CO2 spectral ranges to study their temporal variability. Seasonal patterns calculated for different latitude bands are discussed for each molecule. These patterns highlight the typical seasonal variations of the species. Geographical distributions of mean radiance value are calculated for each month and year, the long term evolution as well as sporadic events are discussed.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-01004655] Status and evolution of the operational IASI L2 products at EUMETSAT: An introduction to the version 6

Geophysical parameters from the IASI instrument on Metop-A are essential products provided from EUMETSAT's Central Facility in near real time. They include vertical profiles of temperature and humidity, related cloud information, surface emissivity and temperature, and atmospheric composition parameters (CO, ozone and several other trace gases). The IASI L2 processor version 5 has been running routinely since September 2010. We give here a short summary of the most recent related validation studies, including results from the Metop-B/IASI L2 Cal/Val activities which started end January 2013, after the conclusion of the first phase of the L1c commissioning. We then introduce the current developments and the future evolutions of the IASI L2 processor operated at EUMETSAT towards the version 6 (v6), which release is scheduled second half of 2013. In particular we will address the integration of new atmospheric composition products from ULB/LATMOS in the scope of O3M-SAF CDOP-2, with first the retrieval of CO profiles. Only the CO total column has been retrieved until version 5. The cloud screening has been improved with the addition of a third detection algorithm based on artificial neural networks and independent from NWP forecasts. We will discuss here the use of concurrent cloud detection methods and the relationship between the cloudiness estimate and the sensing products yield and quality. A quality indicator is associated to the retrieved geophysical parameters in v6. Lastly, new retrieval methods for temperature and water-vapour sounding have been developed, including joint use of micro-wave (MW) and infrared (IR) measurements. The statistical MW+IR retrieval scheme, developed for v6, takes advantage of AMSU and MHS measurements collocated with IASI L1c spectra. It allows for sounding below the clouds in most cloud contaminated IFOVs with improved performances (typically about 1K rms) as compared to the current operational IR-based partly-cloudy retrieval. The MWIR-derived temperature and humidity profiles are used to constrain the retrieval of temperature, humidity and ozone 1D-Var retrievals in clear sky. The latter are performed with reconstructed radiances from a new channel selection and a scene-dependent bias correction. Initial results with the version 6 using ECMWF analyses as reference have shown that the temperature profiles are improved by 0.2 to 0.5K rms in the lower troposphere and that the precision in water-vapour profiles is increased by 30 to 50% in the boundary layer.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00816523] The IASI mission after 2020: what to expect for atmospheric composition monitoring. (poster)

In terms of Earth observing capability, the horizon is shrinking as only a few new satellite missions have been approved and will be financed in the coming years. This is particularly true for polar-orbiting nadir viewing instruments using the thermal radiation emitted by the Earth's surface to probe the troposphere. After 2020 there should be an unprecedented combination of more frequent observation from the geostationary orbit (Meteosat Third Generation (MTG)/Sentinel 4 program) with more precise measurements from the polar orbit (MetOp- Second Generation satellites as part of the EPS-Second Generation/Sentinel 5 program). Along with several other instruments, the latter should embark the IASI-New Generation (IASI-NG) mission. The IASI-NG mission is a versatile mission that builds on the legacy of IASI and fulfills the needs of three different communities: numerical weather forecast, climate research and atmospheric composition monitoring. The instrument is currently designed by CNES and both the spectral resolution and the signal/noise ratio should be improved by at least a factor of two. In order to converge on the design of such an instrument all three communities had to make "reasonable accommodations". The presentation will describe what to expect in terms of products, accuracy and vertical resolution.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00732699] Validation of MIPAS IMK/IAA ozone profiles

We present the results of extensive validation program of Version V5R_O3_220 of ozone vertical profiles retrieved with IMK/IAA MIPAS scientific level 2 processor from version 5 of spectral Level 1 files provided by ESA. The time period covered corresponds to Reduced Resolution period of MIPAS instrument, i.e. January 2005-present. The comparison with satellite instruments includes ACE-FTS, MLS, GOMOS, SCIAMACHY, OSIRIS, HALOE and POAM. The comparison with ground-based instruments includes 5 stations from SHADOZ Network and LIDAR from NDACC network. Also, the comparison with Mark IV balloon measurements is presented. For each reference dataset, bias determination and precision validation are performed.



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50

[hal-00734141] Biogenic Methanol and Formic Acid Constrained from IASI Measurements

Methanol and formic acid, the simplest alcohol and carboxylic acid in the atmosphere, are directly emitted from anthropogenic activities, fire events and vegetation, as well as from photochemical sources. They are removed from the atmosphere through OH oxidation, and wet and dry deposition, and their global lifetime is estimated to 6 days for methanol and to 4 days for formic acid. According to state-of-art estimates, the ocean and terrestrial biosphere account for two thirds of the total methanol source, whereas the contributions from human activities and biomass burning are minor. Plant emissions represent the major part of the methanol flux from terrestrial ecosystems, but the uncertainty regarding the magnitude and localization of this source is very large, ranging between 100 and 300 Tg on an annual basis. Formic acid is a ubiquitous trace gas in air and precipitation and a major contributor to rain acidity in remote environments. Its sources, however, are far from being fully understood, as testify severe underpredictions of observed formic acid concentrations in earlier global modelling studies, spotting the existence of unaccounted sources. New insights into our understanding of methanol and formic acid atmospheric cycle are brought forward by newly acquired measurements of tropospheric columns retrieved from the IASI thermal infrared satellite sounder. In this communication, we report findings from two source inversion studies of methanol and formic acid emissions performed using the IMAGESv2 CTM constrained by one complete year of IASI column measurements. The optimized global methanol source is estimated to about 100 Tg on a yearly basis, with significant emission decreases, compared to the bottom-up inventory, inferred over tropical rainforests and unexpectedly high flux strengths in arid environments. The IASI column data suggest an annual formic acid source about three times higher than estimated from known sources, with a biogenic contribution of about 90%, mostly from tropical and boreal forests. We investigate the implications of the large formic source on precipitation acidity on the global scale. The resulting fluxes are extensively evaluated against previous modelling work, available aircraft and in situ independent measurements. Variabilities of Chemical Species Over the Mediterranean Basin: Measurements



from HAL : Dernières publications https://hal.archives-ouvertes.fr/search/hal/?omitHeader=true&q=%2A&fq=NOT+instance_s%3Asfo&fq=NOT+instance_s%3Adumas&fq=NOT+instance_s%3Amemsic&fq=NOT+%28instance_s%3Ainria+AND+docType_s%3A%28MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Aafssa+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aenpc+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Auniv-mlv+AND+docType_s%3A%28OTHERREPORT+OR+MINUTES+OR+NOTE+OR+MEM+OR+PRESCONF%29%29&fq=NOT+%28instance_s%3Ademocrite+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Aafrique+AND+docType_s%3AMEM%29&fq=NOT+%28instance_s%3Asaga+AND+docType_s%3A%28PRESCONF+OR+BOOKREPORT%29%29&fq=NOT+status_i%3A111&fq=%7B%21tag%3Dtag0__domain_t%7Ddomain_t%3A%28phys%29&defType=edismax&rows=50