77 research outputs found
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Empirical models for estimating monthly global solar radiation: a most comprehensive review and comparative case study in China
Global solar radiation is a core component of scientific research and engineering application across a broad spectrum. However, its measurement is limited by a small number of stations due to the technical and financial restricts. Estimating solar radiation with the meteorological variables using empirical models is of benefit to obtain solar radiation data at global scale. Yet, there are various options of available empirical models to select the most suitable one. This study conducted a most comprehensive collection and review of empirical models employing the commonly measured meteorological variables and geographic factors. A total of 294 different types of empirical models were collected and classified into 37 groups according to input attributes. Such collection built an empirical model library providing an overall overview of the developed empirical models in literatures. Furthermore, the collected models were calibrated and evaluated at three meteorological stations in the Three Gorges Reservoir Area in China. This study suggests that these model-comparing processes can assist the governments, scientists and engineers in tailoring the most fitted model for specific applications and in particular areas
Approche quantitative et qualitative d'un probleme de securite industrielle
Dogniaux, A. 1978. Quantitative and qualitative approach to an industrial safety problem. Journal of Occupational Accidents, 1: 311-330. The case of a Belgian foundry is studied in its work safety aspects. A statistical approach exploring various parameters provides evidence for a paradoxical situation: the unit of the factory that is expected to be the most dangerous, according to technical criteria, is in fact the safest. A psychosociological approach tries to bring some explanation by studying the attitude of the personnel towards the factory's norms and its philosophy of safety. The need for a global socio-technical analysis is illustrated as a condition for a diagnosis in order to assist future prevention. © 1978.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Suivi de la concentration atmosphĂ©rique de CO2 par satellite : performances et sensibilitĂ©s des prochains concepts dâobservation dans le proche infrarouge
The monitoring of anthropogenic CO2 emissions is crucial to assess the progress made towards the 2015 Paris Agreement objectives, and estimations of CO2 atmospheric concentration from satellite observations in the near and shortwave infrared can help to reach this goal. Thus, many concepts of greenhouse gas observing satellites are planned or are currently being developed for this opening decade. The very nature of their measurements, their spectral, radiometric and spatial resolutions greatly vary depending on whether they are targeting natural and/or anthropogenic CO2 fluxes. This work aims to study how the characteristics of these upcoming concepts impact the performance and sensitivities of the CO2 atmospheric concentration estimations made from their measurements. For this purpose, we first present the 5AI inverse radiative transfer model that relies on the Optimal Estimation algorithm and the 4A/OP forward radiative transfer model. It is applied on real measurements performed by the currently flying American Orbiting Carbon Observatory-2 mission, and the sensitivities of the retrievals results to the accounting of the detrimental scattering effects by aerosols and to the knowledge of atmospheric gaseous absorption, brought by molecular spectroscopy, are especially studied. The 5AI inverse model is then applied to assess the performance of the concept proposed by the Space CARBon Observatory (SCARBO) which consists in estimating CO2 atmospheric concentration from truncated interferograms, instead of radiance spectra like most the CO2 observing concepts currently flying or being developed. These truncated interferograms would be measured by the NanoCarb instrument, a miniaturized imaging interferometer which could be carried on a constellation of small satellites, that would have an increased revisit frequency of anthropogenic CO2 emission hotspots compared to single-platform satellite missions. The original measurement approach proposed but the SCARBO concept allows for an increased spatial resolution that enables to distinguish anthropogenic CO2 emission plumes. On the other hand, a trade-off between spatial and spectral resolutions is performed in order to enable the observing concepts that rely on spectra measurements to observe CO2 emission plumes. Thus, we finally study how spectral resolution, radiometric noise and misknwoledge of scattering particles and other interfering geophysical variables, and of spectroscopic parameters impact the performance and/or sensitivities of these CO2 observing concepts.Le suivi des Ă©missions anthropiques de CO2 est crucial pour Ă©valuer les progrĂšs rĂ©alisĂ©s vers les objectifs de lâAccord de Paris signĂ© en 2015, et les estimations de la concentration atmosphĂ©rique de CO2, rĂ©alisĂ©es Ă partir de mesures satellites du rayonnement proche infrarouge, peuvent y contribuer. Ainsi, de nombreux concepts dâobservation satellite dĂ©diĂ©s au suivi du CO2 ou Ă dâautres gaz Ă effet de serre sont planifiĂ©s ou en cours de dĂ©veloppement pour la dĂ©cennie qui sâouvre. La nature mĂȘme des mesures quâils feront, leurs rĂ©solutions spectrale, radiomĂ©trique et spatiale varient grandement selon quâils visent le suivi des flux naturels et/ou anthropiques de CO2. Ce travail de thĂšse propose dâĂ©tudier comment les caractĂ©ristiques de ces prochains concepts modifient les performances de l'estimation de la concentration atmosphĂ©rique de CO2 Ă partir de leurs mesures. Pour le mener Ă bien, le modĂšle de transfert radiatif inverse 5AI, reposant sur lâalgorithme dâestimation optimale et la modĂ©lisation directe de 4A/OP est dâabord prĂ©sentĂ©, puis testĂ© sur les mesures de la mission amĂ©ricaine Orbiting Carbon Observatory-2 actuellement en vol. Les sensibilitĂ©s des rĂ©sultats obtenus Ă prise en compte de lâeffet parasite des aĂ©rosols ainsi quâĂ la connaissance des coefficients dâabsorption des gaz, apportĂ©e par la spectroscopie molĂ©culaire, sont en particulier Ă©tudiĂ©es. Ce modĂšle inverse est ensuite utilisĂ© pour Ă©valuer les performances du concept Space CARBone Observatory (SCARBO) qui propose dâestimer la concentration atmosphĂ©rique de CO2 Ă partir dâinterfĂ©rogrammes tronquĂ©s, et non pas de spectres comme la majoritĂ© des concepts dâobservation Ă lâĂ©tude. Ces interfĂ©rogrammes tronquĂ©s seraient mesurĂ©s par lâinstrument imageur miniaturisĂ© NanoCarb qui serait embarquĂ© sur de petits satellites volant en constellation, permettant dâaugmenter la frĂ©quence de survol des principales sources dâĂ©missions anthropiques de CO2 par rapport aux missions spatiales Ă plateforme unique. Lâapproche de mesure originale proposĂ©e par SCARBO autorise par ailleurs une rĂ©solution spatiale des mesures suffisante pour distinguer les panaches dâĂ©missions anthropiques de CO2. Les concepts reposant sur des mesures de spectres rĂ©alisent quant Ă eux un compromis entre rĂ©solutions spectrale et spatiale pour pouvoir observer les panaches. On Ă©tudie donc finalement lâimpact de lâĂ©volution de la rĂ©solution spectrale, du bruit radiomĂ©trique mais aussi de la mĂ©connaissance de la spectroscopie et des aĂ©rosols sur les performances et sensibilitĂ©s des diffĂ©rents concepts proposĂ©s pour le suivi de la concentration atmosphĂ©rique de CO2
Monitoring CO2 atmospheric concentration from space : performance and sensitivities of the upcoming satellite observation concepts in the shortwave infrared
Le suivi des Ă©missions anthropiques de CO2 est crucial pour Ă©valuer les progrĂšs rĂ©alisĂ©s vers les objectifs de lâAccord de Paris signĂ© en 2015, et les estimations de la concentration atmosphĂ©rique de CO2, rĂ©alisĂ©es Ă partir de mesures satellites du rayonnement proche infrarouge, peuvent y contribuer. Ainsi, de nombreux concepts dâobservation satellite dĂ©diĂ©s au suivi du CO2 ou Ă dâautres gaz Ă effet de serre sont planifiĂ©s ou en cours de dĂ©veloppement pour la dĂ©cennie qui sâouvre. La nature mĂȘme des mesures quâils feront, leurs rĂ©solutions spectrale, radiomĂ©trique et spatiale varient grandement selon quâils visent le suivi des flux naturels et/ou anthropiques de CO2. Ce travail de thĂšse propose dâĂ©tudier comment les caractĂ©ristiques de ces prochains concepts modifient les performances de l'estimation de la concentration atmosphĂ©rique de CO2 Ă partir de leurs mesures. Pour le mener Ă bien, le modĂšle de transfert radiatif inverse 5AI, reposant sur lâalgorithme dâestimation optimale et la modĂ©lisation directe de 4A/OP est dâabord prĂ©sentĂ©, puis testĂ© sur les mesures de la mission amĂ©ricaine Orbiting Carbon Observatory-2 actuellement en vol. Les sensibilitĂ©s des rĂ©sultats obtenus Ă prise en compte de lâeffet parasite des aĂ©rosols ainsi quâĂ la connaissance des coefficients dâabsorption des gaz, apportĂ©e par la spectroscopie molĂ©culaire, sont en particulier Ă©tudiĂ©es. Ce modĂšle inverse est ensuite utilisĂ© pour Ă©valuer les performances du concept Space CARBone Observatory (SCARBO) qui propose dâestimer la concentration atmosphĂ©rique de CO2 Ă partir dâinterfĂ©rogrammes tronquĂ©s, et non pas de spectres comme la majoritĂ© des concepts dâobservation Ă lâĂ©tude. Ces interfĂ©rogrammes tronquĂ©s seraient mesurĂ©s par lâinstrument imageur miniaturisĂ© NanoCarb qui serait embarquĂ© sur de petits satellites volant en constellation, permettant dâaugmenter la frĂ©quence de survol des principales sources dâĂ©missions anthropiques de CO2 par rapport aux missions spatiales Ă plateforme unique. Lâapproche de mesure originale proposĂ©e par SCARBO autorise par ailleurs une rĂ©solution spatiale des mesures suffisante pour distinguer les panaches dâĂ©missions anthropiques de CO2. Les concepts reposant sur des mesures de spectres rĂ©alisent quant Ă eux un compromis entre rĂ©solutions spectrale et spatiale pour pouvoir observer les panaches. On Ă©tudie donc finalement lâimpact de lâĂ©volution de la rĂ©solution spectrale, du bruit radiomĂ©trique mais aussi de la mĂ©connaissance de la spectroscopie et des aĂ©rosols sur les performances et sensibilitĂ©s des diffĂ©rents concepts proposĂ©s pour le suivi de la concentration atmosphĂ©rique de CO2.The monitoring of anthropogenic CO2 emissions is crucial to assess the progress made towards the 2015 Paris Agreement objectives, and estimations of CO2 atmospheric concentration from satellite observations in the near and shortwave infrared can help to reach this goal. Thus, many concepts of greenhouse gas observing satellites are planned or are currently being developed for this opening decade. The very nature of their measurements, their spectral, radiometric and spatial resolutions greatly vary depending on whether they are targeting natural and/or anthropogenic CO2 fluxes. This work aims to study how the characteristics of these upcoming concepts impact the performance and sensitivities of the CO2 atmospheric concentration estimations made from their measurements. For this purpose, we first present the 5AI inverse radiative transfer model that relies on the Optimal Estimation algorithm and the 4A/OP forward radiative transfer model. It is applied on real measurements performed by the currently flying American Orbiting Carbon Observatory-2 mission, and the sensitivities of the retrievals results to the accounting of the detrimental scattering effects by aerosols and to the knowledge of atmospheric gaseous absorption, brought by molecular spectroscopy, are especially studied. The 5AI inverse model is then applied to assess the performance of the concept proposed by the Space CARBon Observatory (SCARBO) which consists in estimating CO2 atmospheric concentration from truncated interferograms, instead of radiance spectra like most the CO2 observing concepts currently flying or being developed. These truncated interferograms would be measured by the NanoCarb instrument, a miniaturized imaging interferometer which could be carried on a constellation of small satellites, that would have an increased revisit frequency of anthropogenic CO2 emission hotspots compared to single-platform satellite missions. The original measurement approach proposed but the SCARBO concept allows for an increased spatial resolution that enables to distinguish anthropogenic CO2 emission plumes. On the other hand, a trade-off between spatial and spectral resolutions is performed in order to enable the observing concepts that rely on spectra measurements to observe CO2 emission plumes. Thus, we finally study how spectral resolution, radiometric noise and misknwoledge of scattering particles and other interfering geophysical variables, and of spectroscopic parameters impact the performance and/or sensitivities of these CO2 observing concepts
Suivi de la concentration atmosphĂ©rique de CO2 par satellite : performances et sensibilitĂ©s des prochains concepts dâobservation dans le proche infrarouge
The monitoring of anthropogenic CO2 emissions is crucial to assess the progress made towards the 2015 Paris Agreement objectives, and estimations of CO2 atmospheric concentration from satellite observations in the near and shortwave infrared can help to reach this goal. Thus, many concepts of greenhouse gas observing satellites are planned or are currently being developed for this opening decade. The very nature of their measurements, their spectral, radiometric and spatial resolutions greatly vary depending on whether they are targeting natural and/or anthropogenic CO2 fluxes. This work aims to study how the characteristics of these upcoming concepts impact the performance and sensitivities of the CO2 atmospheric concentration estimations made from their measurements. For this purpose, we first present the 5AI inverse radiative transfer model that relies on the Optimal Estimation algorithm and the 4A/OP forward radiative transfer model. It is applied on real measurements performed by the currently flying American Orbiting Carbon Observatory-2 mission, and the sensitivities of the retrievals results to the accounting of the detrimental scattering effects by aerosols and to the knowledge of atmospheric gaseous absorption, brought by molecular spectroscopy, are especially studied. The 5AI inverse model is then applied to assess the performance of the concept proposed by the Space CARBon Observatory (SCARBO) which consists in estimating CO2 atmospheric concentration from truncated interferograms, instead of radiance spectra like most the CO2 observing concepts currently flying or being developed. These truncated interferograms would be measured by the NanoCarb instrument, a miniaturized imaging interferometer which could be carried on a constellation of small satellites, that would have an increased revisit frequency of anthropogenic CO2 emission hotspots compared to single-platform satellite missions. The original measurement approach proposed but the SCARBO concept allows for an increased spatial resolution that enables to distinguish anthropogenic CO2 emission plumes. On the other hand, a trade-off between spatial and spectral resolutions is performed in order to enable the observing concepts that rely on spectra measurements to observe CO2 emission plumes. Thus, we finally study how spectral resolution, radiometric noise and misknwoledge of scattering particles and other interfering geophysical variables, and of spectroscopic parameters impact the performance and/or sensitivities of these CO2 observing concepts.Le suivi des Ă©missions anthropiques de CO2 est crucial pour Ă©valuer les progrĂšs rĂ©alisĂ©s vers les objectifs de lâAccord de Paris signĂ© en 2015, et les estimations de la concentration atmosphĂ©rique de CO2, rĂ©alisĂ©es Ă partir de mesures satellites du rayonnement proche infrarouge, peuvent y contribuer. Ainsi, de nombreux concepts dâobservation satellite dĂ©diĂ©s au suivi du CO2 ou Ă dâautres gaz Ă effet de serre sont planifiĂ©s ou en cours de dĂ©veloppement pour la dĂ©cennie qui sâouvre. La nature mĂȘme des mesures quâils feront, leurs rĂ©solutions spectrale, radiomĂ©trique et spatiale varient grandement selon quâils visent le suivi des flux naturels et/ou anthropiques de CO2. Ce travail de thĂšse propose dâĂ©tudier comment les caractĂ©ristiques de ces prochains concepts modifient les performances de l'estimation de la concentration atmosphĂ©rique de CO2 Ă partir de leurs mesures. Pour le mener Ă bien, le modĂšle de transfert radiatif inverse 5AI, reposant sur lâalgorithme dâestimation optimale et la modĂ©lisation directe de 4A/OP est dâabord prĂ©sentĂ©, puis testĂ© sur les mesures de la mission amĂ©ricaine Orbiting Carbon Observatory-2 actuellement en vol. Les sensibilitĂ©s des rĂ©sultats obtenus Ă prise en compte de lâeffet parasite des aĂ©rosols ainsi quâĂ la connaissance des coefficients dâabsorption des gaz, apportĂ©e par la spectroscopie molĂ©culaire, sont en particulier Ă©tudiĂ©es. Ce modĂšle inverse est ensuite utilisĂ© pour Ă©valuer les performances du concept Space CARBone Observatory (SCARBO) qui propose dâestimer la concentration atmosphĂ©rique de CO2 Ă partir dâinterfĂ©rogrammes tronquĂ©s, et non pas de spectres comme la majoritĂ© des concepts dâobservation Ă lâĂ©tude. Ces interfĂ©rogrammes tronquĂ©s seraient mesurĂ©s par lâinstrument imageur miniaturisĂ© NanoCarb qui serait embarquĂ© sur de petits satellites volant en constellation, permettant dâaugmenter la frĂ©quence de survol des principales sources dâĂ©missions anthropiques de CO2 par rapport aux missions spatiales Ă plateforme unique. Lâapproche de mesure originale proposĂ©e par SCARBO autorise par ailleurs une rĂ©solution spatiale des mesures suffisante pour distinguer les panaches dâĂ©missions anthropiques de CO2. Les concepts reposant sur des mesures de spectres rĂ©alisent quant Ă eux un compromis entre rĂ©solutions spectrale et spatiale pour pouvoir observer les panaches. On Ă©tudie donc finalement lâimpact de lâĂ©volution de la rĂ©solution spectrale, du bruit radiomĂ©trique mais aussi de la mĂ©connaissance de la spectroscopie et des aĂ©rosols sur les performances et sensibilitĂ©s des diffĂ©rents concepts proposĂ©s pour le suivi de la concentration atmosphĂ©rique de CO2
Suivi de la concentration atmosphĂ©rique de CO2 par satellite : performances et sensibilitĂ©s des prochains concepts dâobservation dans le proche infrarouge
The monitoring of anthropogenic CO2 emissions is crucial to assess the progress made towards the 2015 Paris Agreement objectives, and estimations of CO2 atmospheric concentration from satellite observations in the near and shortwave infrared can help to reach this goal. Thus, many concepts of greenhouse gas observing satellites are planned or are currently being developed for this opening decade. The very nature of their measurements, their spectral, radiometric and spatial resolutions greatly vary depending on whether they are targeting natural and/or anthropogenic CO2 fluxes. This work aims to study how the characteristics of these upcoming concepts impact the performance and sensitivities of the CO2 atmospheric concentration estimations made from their measurements. For this purpose, we first present the 5AI inverse radiative transfer model that relies on the Optimal Estimation algorithm and the 4A/OP forward radiative transfer model. It is applied on real measurements performed by the currently flying American Orbiting Carbon Observatory-2 mission, and the sensitivities of the retrievals results to the accounting of the detrimental scattering effects by aerosols and to the knowledge of atmospheric gaseous absorption, brought by molecular spectroscopy, are especially studied. The 5AI inverse model is then applied to assess the performance of the concept proposed by the Space CARBon Observatory (SCARBO) which consists in estimating CO2 atmospheric concentration from truncated interferograms, instead of radiance spectra like most the CO2 observing concepts currently flying or being developed. These truncated interferograms would be measured by the NanoCarb instrument, a miniaturized imaging interferometer which could be carried on a constellation of small satellites, that would have an increased revisit frequency of anthropogenic CO2 emission hotspots compared to single-platform satellite missions. The original measurement approach proposed but the SCARBO concept allows for an increased spatial resolution that enables to distinguish anthropogenic CO2 emission plumes. On the other hand, a trade-off between spatial and spectral resolutions is performed in order to enable the observing concepts that rely on spectra measurements to observe CO2 emission plumes. Thus, we finally study how spectral resolution, radiometric noise and misknwoledge of scattering particles and other interfering geophysical variables, and of spectroscopic parameters impact the performance and/or sensitivities of these CO2 observing concepts.Le suivi des Ă©missions anthropiques de CO2 est crucial pour Ă©valuer les progrĂšs rĂ©alisĂ©s vers les objectifs de lâAccord de Paris signĂ© en 2015, et les estimations de la concentration atmosphĂ©rique de CO2, rĂ©alisĂ©es Ă partir de mesures satellites du rayonnement proche infrarouge, peuvent y contribuer. Ainsi, de nombreux concepts dâobservation satellite dĂ©diĂ©s au suivi du CO2 ou Ă dâautres gaz Ă effet de serre sont planifiĂ©s ou en cours de dĂ©veloppement pour la dĂ©cennie qui sâouvre. La nature mĂȘme des mesures quâils feront, leurs rĂ©solutions spectrale, radiomĂ©trique et spatiale varient grandement selon quâils visent le suivi des flux naturels et/ou anthropiques de CO2. Ce travail de thĂšse propose dâĂ©tudier comment les caractĂ©ristiques de ces prochains concepts modifient les performances de l'estimation de la concentration atmosphĂ©rique de CO2 Ă partir de leurs mesures. Pour le mener Ă bien, le modĂšle de transfert radiatif inverse 5AI, reposant sur lâalgorithme dâestimation optimale et la modĂ©lisation directe de 4A/OP est dâabord prĂ©sentĂ©, puis testĂ© sur les mesures de la mission amĂ©ricaine Orbiting Carbon Observatory-2 actuellement en vol. Les sensibilitĂ©s des rĂ©sultats obtenus Ă prise en compte de lâeffet parasite des aĂ©rosols ainsi quâĂ la connaissance des coefficients dâabsorption des gaz, apportĂ©e par la spectroscopie molĂ©culaire, sont en particulier Ă©tudiĂ©es. Ce modĂšle inverse est ensuite utilisĂ© pour Ă©valuer les performances du concept Space CARBone Observatory (SCARBO) qui propose dâestimer la concentration atmosphĂ©rique de CO2 Ă partir dâinterfĂ©rogrammes tronquĂ©s, et non pas de spectres comme la majoritĂ© des concepts dâobservation Ă lâĂ©tude. Ces interfĂ©rogrammes tronquĂ©s seraient mesurĂ©s par lâinstrument imageur miniaturisĂ© NanoCarb qui serait embarquĂ© sur de petits satellites volant en constellation, permettant dâaugmenter la frĂ©quence de survol des principales sources dâĂ©missions anthropiques de CO2 par rapport aux missions spatiales Ă plateforme unique. Lâapproche de mesure originale proposĂ©e par SCARBO autorise par ailleurs une rĂ©solution spatiale des mesures suffisante pour distinguer les panaches dâĂ©missions anthropiques de CO2. Les concepts reposant sur des mesures de spectres rĂ©alisent quant Ă eux un compromis entre rĂ©solutions spectrale et spatiale pour pouvoir observer les panaches. On Ă©tudie donc finalement lâimpact de lâĂ©volution de la rĂ©solution spectrale, du bruit radiomĂ©trique mais aussi de la mĂ©connaissance de la spectroscopie et des aĂ©rosols sur les performances et sensibilitĂ©s des diffĂ©rents concepts proposĂ©s pour le suivi de la concentration atmosphĂ©rique de CO2
Suivi de la concentration atmosphĂ©rique de CO2 par satellite : performances et sensibilitĂ©s des prochains concepts dâobservation dans le proche infrarouge
The monitoring of anthropogenic CO2 emissions is crucial to assess the progress made towards the 2015 Paris Agreement objectives, and estimations of CO2 atmospheric concentration from satellite observations in the near and shortwave infrared can help to reach this goal. Thus, many concepts of greenhouse gas observing satellites are planned or are currently being developed for this opening decade. The very nature of their measurements, their spectral, radiometric and spatial resolutions greatly vary depending on whether they are targeting natural and/or anthropogenic CO2 fluxes. This work aims to study how the characteristics of these upcoming concepts impact the performance and sensitivities of the CO2 atmospheric concentration estimations made from their measurements. For this purpose, we first present the 5AI inverse radiative transfer model that relies on the Optimal Estimation algorithm and the 4A/OP forward radiative transfer model. It is applied on real measurements performed by the currently flying American Orbiting Carbon Observatory-2 mission, and the sensitivities of the retrievals results to the accounting of the detrimental scattering effects by aerosols and to the knowledge of atmospheric gaseous absorption, brought by molecular spectroscopy, are especially studied. The 5AI inverse model is then applied to assess the performance of the concept proposed by the Space CARBon Observatory (SCARBO) which consists in estimating CO2 atmospheric concentration from truncated interferograms, instead of radiance spectra like most the CO2 observing concepts currently flying or being developed. These truncated interferograms would be measured by the NanoCarb instrument, a miniaturized imaging interferometer which could be carried on a constellation of small satellites, that would have an increased revisit frequency of anthropogenic CO2 emission hotspots compared to single-platform satellite missions. The original measurement approach proposed but the SCARBO concept allows for an increased spatial resolution that enables to distinguish anthropogenic CO2 emission plumes. On the other hand, a trade-off between spatial and spectral resolutions is performed in order to enable the observing concepts that rely on spectra measurements to observe CO2 emission plumes. Thus, we finally study how spectral resolution, radiometric noise and misknwoledge of scattering particles and other interfering geophysical variables, and of spectroscopic parameters impact the performance and/or sensitivities of these CO2 observing concepts.Le suivi des Ă©missions anthropiques de CO2 est crucial pour Ă©valuer les progrĂšs rĂ©alisĂ©s vers les objectifs de lâAccord de Paris signĂ© en 2015, et les estimations de la concentration atmosphĂ©rique de CO2, rĂ©alisĂ©es Ă partir de mesures satellites du rayonnement proche infrarouge, peuvent y contribuer. Ainsi, de nombreux concepts dâobservation satellite dĂ©diĂ©s au suivi du CO2 ou Ă dâautres gaz Ă effet de serre sont planifiĂ©s ou en cours de dĂ©veloppement pour la dĂ©cennie qui sâouvre. La nature mĂȘme des mesures quâils feront, leurs rĂ©solutions spectrale, radiomĂ©trique et spatiale varient grandement selon quâils visent le suivi des flux naturels et/ou anthropiques de CO2. Ce travail de thĂšse propose dâĂ©tudier comment les caractĂ©ristiques de ces prochains concepts modifient les performances de l'estimation de la concentration atmosphĂ©rique de CO2 Ă partir de leurs mesures. Pour le mener Ă bien, le modĂšle de transfert radiatif inverse 5AI, reposant sur lâalgorithme dâestimation optimale et la modĂ©lisation directe de 4A/OP est dâabord prĂ©sentĂ©, puis testĂ© sur les mesures de la mission amĂ©ricaine Orbiting Carbon Observatory-2 actuellement en vol. Les sensibilitĂ©s des rĂ©sultats obtenus Ă prise en compte de lâeffet parasite des aĂ©rosols ainsi quâĂ la connaissance des coefficients dâabsorption des gaz, apportĂ©e par la spectroscopie molĂ©culaire, sont en particulier Ă©tudiĂ©es. Ce modĂšle inverse est ensuite utilisĂ© pour Ă©valuer les performances du concept Space CARBone Observatory (SCARBO) qui propose dâestimer la concentration atmosphĂ©rique de CO2 Ă partir dâinterfĂ©rogrammes tronquĂ©s, et non pas de spectres comme la majoritĂ© des concepts dâobservation Ă lâĂ©tude. Ces interfĂ©rogrammes tronquĂ©s seraient mesurĂ©s par lâinstrument imageur miniaturisĂ© NanoCarb qui serait embarquĂ© sur de petits satellites volant en constellation, permettant dâaugmenter la frĂ©quence de survol des principales sources dâĂ©missions anthropiques de CO2 par rapport aux missions spatiales Ă plateforme unique. Lâapproche de mesure originale proposĂ©e par SCARBO autorise par ailleurs une rĂ©solution spatiale des mesures suffisante pour distinguer les panaches dâĂ©missions anthropiques de CO2. Les concepts reposant sur des mesures de spectres rĂ©alisent quant Ă eux un compromis entre rĂ©solutions spectrale et spatiale pour pouvoir observer les panaches. On Ă©tudie donc finalement lâimpact de lâĂ©volution de la rĂ©solution spectrale, du bruit radiomĂ©trique mais aussi de la mĂ©connaissance de la spectroscopie et des aĂ©rosols sur les performances et sensibilitĂ©s des diffĂ©rents concepts proposĂ©s pour le suivi de la concentration atmosphĂ©rique de CO2
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