Wavelet methods have become a very much common tool for exploring and analyzing solar data. Many methods have been developed. I will briefly describe three different methods: Wavelet Power Spectra (WPS), Ampligrams, and Multi-Resolution Analysis (MRA). I will then give examples of how the wavelet methods have been applied to indicators of solar activity. Interestingly these studies raise fundamental questions about what we mean by solar activity and how good the indicators are.
{"title":"Wavelet reconstructions of solar magnetic activity","authors":"H. Lundstedt","doi":"10.1051/JP4:2006139012","DOIUrl":"https://doi.org/10.1051/JP4:2006139012","url":null,"abstract":"Wavelet methods have become a very much common tool for exploring and analyzing solar data. Many methods have been developed. I will briefly describe three different methods: Wavelet Power Spectra (WPS), Ampligrams, and Multi-Resolution Analysis (MRA). I will then give examples of how the wavelet methods have been applied to indicators of solar activity. Interestingly these studies raise fundamental questions about what we mean by solar activity and how good the indicators are.","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"29 1","pages":"167-174"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74917043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Valentin, O. Boyko, G. Rey, Brigitte Mercier, E. Papalazarou, Laura Antonucci
Dans le but de developper une source intense EUV pour les applications, nous avons realise des experiences d'optimisation du signal harmonique. La generation d'harmoniques d'ordre eleve est tres sensible a la forme de l'impulsion du laser fondamental. Nous avons utilise un filtre acousto-optique dispersif programmable (Dazzler) afin de modifier la phase spectrale du laser fondamental. Nous avons optimise le signal harmonique genere dans l'argon a l'aide d'un algorithme genetique jusqu'a un facteur 10. Nous montrons l'influence des parametres macroscopiques de generation sur le processus d'optimisation.
{"title":"Étude expérimentale de l'optimisation de la génération d'harmoniques d'ordre élevé par l'utilisation d'un algorithme génétique","authors":"C. Valentin, O. Boyko, G. Rey, Brigitte Mercier, E. Papalazarou, Laura Antonucci","doi":"10.1051/JP4:2006138005","DOIUrl":"https://doi.org/10.1051/JP4:2006138005","url":null,"abstract":"Dans le but de developper une source intense EUV pour les applications, nous avons realise des experiences d'optimisation du signal harmonique. La generation d'harmoniques d'ordre eleve est tres sensible a la forme de l'impulsion du laser fondamental. Nous avons utilise un filtre acousto-optique dispersif programmable (Dazzler) afin de modifier la phase spectrale du laser fondamental. Nous avons optimise le signal harmonique genere dans l'argon a l'aide d'un algorithme genetique jusqu'a un facteur 10. Nous montrons l'influence des parametres macroscopiques de generation sur le processus d'optimisation.","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"129 9 1","pages":"35-41"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80234681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Point, É. Robert, S. Dozias, C. Cachoncinlle, R. Viladrosa
Cette contribution se propose de presenter les derniers developpements d'une etude dont l'objectif est d'ameliorer l'efficacite energetique et les performances lumineuses d'enseignes sans mercure excitees en regime impulsionnel. Ces etudes ont montre que, pour un melange de neon et de xenon, l'utilisation de pressions relativement elevees permet de favoriser l'emission a 147 nm du xenon, laquelle est capable d'exciter les phosphores des enseignes. Par ailleurs, on a pu mettre en evidence que l'elevation de pression s'accompagne de la production d'excimeres et du developpement de bandes d'emissions moleculaires dans l'ultraviolet du vide (VUV).
{"title":"Effet de la pression de mélange sur le rayonnement VUV du xénon dans le cas d'enseignes lumineuses sans mercure excitées en régime d'impulsions électriques","authors":"S. Point, É. Robert, S. Dozias, C. Cachoncinlle, R. Viladrosa","doi":"10.1051/JP4:2006138013","DOIUrl":"https://doi.org/10.1051/JP4:2006138013","url":null,"abstract":"Cette contribution se propose de presenter les derniers developpements d'une etude dont l'objectif est d'ameliorer l'efficacite energetique et les performances lumineuses d'enseignes sans mercure excitees en regime impulsionnel. Ces etudes ont montre que, pour un melange de neon et de xenon, l'utilisation de pressions relativement elevees permet de favoriser l'emission a 147 nm du xenon, laquelle est capable d'exciter les phosphores des enseignes. Par ailleurs, on a pu mettre en evidence que l'elevation de pression s'accompagne de la production d'excimeres et du developpement de bandes d'emissions moleculaires dans l'ultraviolet du vide (VUV).","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"26 1","pages":"105-110"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79438511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper is presents a concise review of regional climate modeling, from its ensuing stages in the late 1980s to the most recent developments. A tremendous progress has been achieved in improving the performance of regional climate models, which are currently used by a growing research community for a wide range of applications, from process studies to paleoclimate and future climate simulations. Basic concepts underlying the nested modeling technique, along with the current debate on outstanding issues in regional climate modeling, are discussed. Finally, perspectives of future developments in this rapidly evolving research area are briefly outlined. An extensive reference list is provided to support the discussion.
{"title":"Regional climate modeling: Status and perspectives","authors":"F. Giorgi","doi":"10.1051/JP4:2006139008","DOIUrl":"https://doi.org/10.1051/JP4:2006139008","url":null,"abstract":"This paper is presents a concise review of regional climate modeling, from its ensuing stages in the late 1980s to the most recent developments. A tremendous progress has been achieved in improving the performance of regional climate models, which are currently used by a growing research community for a wide range of applications, from process studies to paleoclimate and future climate simulations. Basic concepts underlying the nested modeling technique, along with the current debate on outstanding issues in regional climate modeling, are discussed. Finally, perspectives of future developments in this rapidly evolving research area are briefly outlined. An extensive reference list is provided to support the discussion.","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"27 1","pages":"101-118"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84436414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ch. Hecquet, M. Roulliay, F. Delmotte, M.-F. Ravet-Krill, A. Hardouin, M. Idir
Le Laboratoire Charles Fabry concoit de nombreuses optiques dont certaines pour les applications dans le spectre EUV. Pour les besoins de caracterisation, il est necessaire de posseder une metrologie a la longueur d'onde d'utilisation proche des moyens de fabrication. Ceci permet d'etudier les composants des leur conception et de caracteriser les optiques. Nous presentons ici les performances d'un reflectometre automatise EUV large spectre. Il a ete developpe dans le cadre de la centrale CEMOX 1 , initiee par le pole PRaXO 2 .
{"title":"Réflectomètre à large spectre EUV pour la métrologie d'optiques","authors":"Ch. Hecquet, M. Roulliay, F. Delmotte, M.-F. Ravet-Krill, A. Hardouin, M. Idir","doi":"10.1051/JP4:2006138030","DOIUrl":"https://doi.org/10.1051/JP4:2006138030","url":null,"abstract":"Le Laboratoire Charles Fabry concoit de nombreuses optiques dont certaines pour les applications dans le spectre EUV. Pour les besoins de caracterisation, il est necessaire de posseder une metrologie a la longueur d'onde d'utilisation proche des moyens de fabrication. Ceci permet d'etudier les composants des leur conception et de caracteriser les optiques. Nous presentons ici les performances d'un reflectometre automatise EUV large spectre. Il a ete developpe dans le cadre de la centrale CEMOX 1 , initiee par le pole PRaXO 2 .","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"28 1","pages":"259-264"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78012738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An effective adaptation to the changing climate at farm, sector and policy level is a prerequisite for reducing negative impacts and for obtaining possible benefits. These adaptations include land use and land management, as well as changes in inputs of water, nutrients and pesticides. Some of the most wide ranging adaptations involve changes in water management and water conservation, which involves issues such as changing irrigation, adoption of drought tolerant crops and water saving cropping methods (e.g. mulching and minimum tillage). Many of these adaptation options have substantial effects on greenhouse gas emissions from agriculture. However, so far few studies have attempted to link the issue of adaptation and mitigation in agriculture. This is primarily because the issues have so far been dealt with by different research communities and within different policy contexts. As both issues are becoming increasingly relevant from a policy perspective, these issues will have to be reconciled. Dealing with these issues requires a highly interdisciplinary approach.
{"title":"Reconciling adaptation and mitigation to climate change in agriculture$^{ast}$","authors":"J. Olesen","doi":"10.1051/JP4:2006139026","DOIUrl":"https://doi.org/10.1051/JP4:2006139026","url":null,"abstract":"An effective adaptation to the changing climate at farm, sector and policy level is a prerequisite for reducing negative impacts and for obtaining possible benefits. These adaptations include land use and land management, as well as changes in inputs of water, nutrients and pesticides. Some of the most wide ranging adaptations involve changes in water management and water conservation, which involves issues such as changing irrigation, adoption of drought tolerant crops and water saving cropping methods (e.g. mulching and minimum tillage). Many of these adaptation options have substantial effects on greenhouse gas emissions from agriculture. However, so far few studies have attempted to link the issue of adaptation and mitigation in agriculture. This is primarily because the issues have so far been dealt with by different research communities and within different policy contexts. As both issues are becoming increasingly relevant from a policy perspective, these issues will have to be reconciled. Dealing with these issues requires a highly interdisciplinary approach.","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"47 1","pages":"403-411"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86305525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water is the key to our existence on this planet and it is involved in nearly all biological, geological, and chemical processes. Life on Earth depends very much on the remarkable properties of water. The availability of freshwater is for many regions one of the key concerns in connection with global climate change. The atmosphere contains only about 0.001% of the water available on our planet. Despite this small amount its horizontal and vertical distribution plays a key role in the global water cycle and the Earth's climate. The atmosphere has direct connections to most of the other reservoirs and steers the redistribution of water between them with an average turnover time of about 10 days. Evaporation over the oceans exceeds precipitation and over land evapotranspiration amounts only to 2/3 of the precipitation reaching the ground. Consequently, there is a net flux of water from the oceans towards the continents, of course via the atmosphere, which has the largest overall volume of fluxes. Water is present in the atmosphere as solid, liquid, or gas. Water vapour is the most important greenhouse gas in the atmosphere and, in addition, changes of water phase and cloud-radiation interaction contribute strongly to the global energy cycle. Water is also a physically and chemically integral part of other biogeochemical cycles. Although there have been large efforts and improvements in recent years, uncertainties in quantifying the components of the atmospheric water cycle still exist. Observational capabilities on the global scale are not satisfactory at present, but the advent of new satellites devoted to the global observation of precipitation and cloud systems along with dedicated modelling projects certainly will improve the situation. Progress is urgently needed to adequately contribute to the answer of one of the central questions in the context of global warming: Is the hydrological cycle accelerating'?
{"title":"Water in the Earth's atmosphere","authors":"M. Quante, V. Matthias","doi":"10.1051/JP4:2006139005","DOIUrl":"https://doi.org/10.1051/JP4:2006139005","url":null,"abstract":"Water is the key to our existence on this planet and it is involved in nearly all biological, geological, and chemical processes. Life on Earth depends very much on the remarkable properties of water. The availability of freshwater is for many regions one of the key concerns in connection with global climate change. The atmosphere contains only about 0.001% of the water available on our planet. Despite this small amount its horizontal and vertical distribution plays a key role in the global water cycle and the Earth's climate. The atmosphere has direct connections to most of the other reservoirs and steers the redistribution of water between them with an average turnover time of about 10 days. Evaporation over the oceans exceeds precipitation and over land evapotranspiration amounts only to 2/3 of the precipitation reaching the ground. Consequently, there is a net flux of water from the oceans towards the continents, of course via the atmosphere, which has the largest overall volume of fluxes. Water is present in the atmosphere as solid, liquid, or gas. Water vapour is the most important greenhouse gas in the atmosphere and, in addition, changes of water phase and cloud-radiation interaction contribute strongly to the global energy cycle. Water is also a physically and chemically integral part of other biogeochemical cycles. Although there have been large efforts and improvements in recent years, uncertainties in quantifying the components of the atmospheric water cycle still exist. Observational capabilities on the global scale are not satisfactory at present, but the advent of new satellites devoted to the global observation of precipitation and cloud systems along with dedicated modelling projects certainly will improve the situation. Progress is urgently needed to adequately contribute to the answer of one of the central questions in the context of global warming: Is the hydrological cycle accelerating'?","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"14 1","pages":"37-61"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83908669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Information regarding the distribution of metallic/metalloid chemical species in biological compartments is required for understanding their biochemical impact on living organisms. To obtain such information implies the use of a dedicated measurement approach, namely speciation analysis. The current trend in (elemental) speciation analysis regards bioinorganic applications. New analytical methodologies are therefore necessary for identification, detection and characterization of metal(loids) complexed or incorporated into biomolecules. The established element-speciation approaches developed for the determination of low molecular mass metal(loid) species (e.g. organometallic compounds) in environmental, food, toxicological and health sciences are presently being adapted for the determination of high molecular mass metal-species, generally related to biological processes. This is one of the newest approaches in terms of element speciation and is called metallomics; this concept refers to the totality of metal species in a cell and covers the inorganic element content and the ensemble of its complexes with biomolecules, particularly proteins, participating in the organisms' response to beneficial or harmful conditions. Compared to conventional elemental speciation analysis, the approach applied to bioinorganic analysis is challenging, particularly given the difficulties in identification/characterization of the organic (e.g. protein) content of such species. In addition, quantification is not feasible with the conventional approaches, which led to the exploitation of the unique feature of (post-column) online isotope dilution-mass spectrometry for species quantification in metallomics.
{"title":"Elemental speciation analysis, from environmental to biochemical challenge","authors":"P. Jitaru, C. Barbante","doi":"10.1051/JP4:2006139019","DOIUrl":"https://doi.org/10.1051/JP4:2006139019","url":null,"abstract":"Information regarding the distribution of metallic/metalloid chemical species in biological compartments is required for understanding their biochemical impact on living organisms. To obtain such information implies the use of a dedicated measurement approach, namely speciation analysis. The current trend in (elemental) speciation analysis regards bioinorganic applications. New analytical methodologies are therefore necessary for identification, detection and characterization of metal(loids) complexed or incorporated into biomolecules. The established element-speciation approaches developed for the determination of low molecular mass metal(loid) species (e.g. organometallic compounds) in environmental, food, toxicological and health sciences are presently being adapted for the determination of high molecular mass metal-species, generally related to biological processes. This is one of the newest approaches in terms of element speciation and is called metallomics; this concept refers to the totality of metal species in a cell and covers the inorganic element content and the ensemble of its complexes with biomolecules, particularly proteins, participating in the organisms' response to beneficial or harmful conditions. Compared to conventional elemental speciation analysis, the approach applied to bioinorganic analysis is challenging, particularly given the difficulties in identification/characterization of the organic (e.g. protein) content of such species. In addition, quantification is not feasible with the conventional approaches, which led to the exploitation of the unique feature of (post-column) online isotope dilution-mass spectrometry for species quantification in metallomics.","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"12 5 1","pages":"269-294"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90173296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A review is given of the dynamical mechanisms responsible for the monsoon circulation over West Africa. Features of the circulation are first described, including the seasonal displacement of the rain bands, the structure of the heat low over the Sahara, the meridional circulation to the south and the associated zonal jets. Simple theories for the zonal-mean meridional circulation are then presented, using the principles of angular momentum conservation, thermal wind balance and moist convective equilibrium. The application of these theories to the West African monsoon reveals a sensitivity to the low-level meridional gradient of equivalent potential temperature, which helps explain observed variability in the monsoon onset. Processes leading to east-west asymmetries in the circulation are also described, and mechanisms linking West African rainfall anomalies with remote events in the tropics are discussed. These dynamical considerations are then placed in the broader context of the ongoing AMMA research program.
{"title":"Dynamics of the West African monsoon","authors":"N. Hall, P. Peyrillé","doi":"10.1051/JP4:2006139007","DOIUrl":"https://doi.org/10.1051/JP4:2006139007","url":null,"abstract":"A review is given of the dynamical mechanisms responsible for the monsoon circulation over West Africa. Features of the circulation are first described, including the seasonal displacement of the rain bands, the structure of the heat low over the Sahara, the meridional circulation to the south and the associated zonal jets. Simple theories for the zonal-mean meridional circulation are then presented, using the principles of angular momentum conservation, thermal wind balance and moist convective equilibrium. The application of these theories to the West African monsoon reveals a sensitivity to the low-level meridional gradient of equivalent potential temperature, which helps explain observed variability in the monsoon onset. Processes leading to east-west asymmetries in the circulation are also described, and mechanisms linking West African rainfall anomalies with remote events in the tropics are discussed. These dynamical considerations are then placed in the broader context of the ongoing AMMA research program.","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"5 1","pages":"81-99"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75386482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A system as complex and extensive as the earth's atmosphere with its chemistry involving gases and particles requires many observations for understanding its workings and following its changes. A logical yet unusual, but potentially extremely powerful way is to use civil aircraft in regular service for making measurements and thus lending science a helping hand. There are 3 such aircraft systems in operation and development which are briefly discussed with emphasis on a container based project, named CARIBIC. It is shown which regions of the atmosphere can be probed, what different air masses are encountered, and what one can measure using a container inside an aircraft as a compact automated laboratory. This is illustrated by 3 examples.
{"title":"Civil aircraft in global atmospheric chemistry research and monitoring","authors":"C. Brenninkmeijer","doi":"10.1051/JP4:2006139021","DOIUrl":"https://doi.org/10.1051/JP4:2006139021","url":null,"abstract":"A system as complex and extensive as the earth's atmosphere with its chemistry involving gases and particles requires many observations for understanding its workings and following its changes. A logical yet unusual, but potentially extremely powerful way is to use civil aircraft in regular service for making measurements and thus lending science a helping hand. There are 3 such aircraft systems in operation and development which are briefly discussed with emphasis on a container based project, named CARIBIC. It is shown which regions of the atmosphere can be probed, what different air masses are encountered, and what one can measure using a container inside an aircraft as a compact automated laboratory. This is illustrated by 3 examples.","PeriodicalId":14838,"journal":{"name":"Journal De Physique Iv","volume":"46 1","pages":"321-336"},"PeriodicalIF":0.0,"publicationDate":"2006-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82223252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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