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Philippe Drobinski - One of the best experts on this subject based on the ideXlab platform.
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Linear theory of the Sea Breeze in a thermal wind
Quarterly Journal of the Royal Meteorological Society, 2011Co-Authors: Philippe Drobinski, Richard Rotunno, Thomas DubosAbstract:This article investigates the linear dynamics of the Sea Breeze in an along-shore thermal wind shear. The present analysis shows that the Sea-Breeze circulation is tilted towards the slanted isentropes associated with the thermal wind. At a critical value of the thermal wind shear, the tilt of the Sea-Breeze circulation becomes equal to the slope of the background isentropes. The present analysis also shows a spatial shift between the heating pattern and the Sea-Breeze circulation. The present linear theory is then applied to interpret measurements made in the vicinity of New York City where there is a warm-Season synoptic southwesterly jet. It is compared with observations and past numerical simulations. Agreement is found with respect to the enhanced along-coast wind that follows the tilted isentropes, the order of magnitude of the isentrope tilt and the clockwise rotating wind hodograph showing the jet maximum peaking at 1800 solar time. There is a disagreement between theory and observations on the phase lag between the jet maximum and the cross-shore pressure gradient maximum. However, this disagreement can reasonably be attributed to either the angle made by the synoptic jet to the coastline and/or the presence of friction. The inland spatial shift of the Breeze indicated by the theory might also be indirectly confirmed by the coastal inlan dw ind observations of al arger diurnal amplitude for a stronger synoptic jet. Copyright c � 2011 Royal Meteorological Society
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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Sea-Breeze-Induced Mass Transport over Complex Terrain in South-eastern France: A Case Study
Quarterly Journal of the Royal Meteorological Society, 2006Co-Authors: Sophie Bastin, Philippe DrobinskiAbstract:The structure and evolution of the Sea Breeze in southern France on 25 June 2001 is investigated experimentally and numerically. This study shows how interactions between the Sea Breeze, the synoptic flow and the complex terrain affect the Sea-Breeze structure, and quantifies and discusses the air-mass transport associated with the Sea-Breeze circulation. The analysis of the front propagation and the associated turbulent kinetic energy budget allows four distinct stages of Sea-Breeze front evolution to be identified. Quantification of the horizontal and vertical air-mass fluxes is related to these four stages: the horizontal advection is directly linked to the intensity of the Sea-Breeze flow. Two main mechanisms contribute to the vertical export within the free troposphere: anabatic upslope winds which are intensified by the Sea-Breeze flow and frontogenesis at the Sea-Breeze front which generates turbulence and mixing and upward motion
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the
2006Co-Authors: Rhône Valley, Patricia Delville, Sophie Bastin, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d’Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain M. Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhône Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhône Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Expérience sur Site pour Contraindre les Modèles de Pollution Atmosphérique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhône Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhône Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhône Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhône Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhône Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
Sophie Bastin - One of the best experts on this subject based on the ideXlab platform.
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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Variability of three-dimensional Sea Breeze structure in southern France: observations and evaluation of empirical scaling laws
Ann. Geophys., 2006Co-Authors: Ph. Drobinski, Abhimanyu Dabas, Patricia Delville, Sophie Bastin, Oliver ReitebuchAbstract:Sea-Breeze dynamics in southern France is investigated using an airborne Doppler lidar, a meteorological surface station network and radiosoundings, in the framework of the ESCOMPTE experiment conducted during summer 2001 in order to evaluate the role of thermal circulations on pollutant transport and ventilation. The airborne Doppler lidar WIND contributed to three-dimensional (3-D) mapping of the Sea Breeze circulation in an unprecedented way. The data allow access to the onshore and offshore Sea Breeze extents (xsb), and to the Sea Breeze depth (zsb) and intensity (usb). They also show that the return flow of the Sea Breeze circulation is very seldom seen in this area due to (i) the presence of a systematic non zero background wind, and (ii) the 3-D structure of the Sea Breeze caused by the complex coastline shape and topography. A thorough analysis is conducted on the impact of the two main valleys (Rhône and Durance valleys) affecting the Sea Breeze circulation in the area.\n\nFinally, this dataset also allows an evaluation of the existing scaling laws used to derive the Sea Breeze intensity, depth and horizontal extent. The main results of this study are that (i) latitude, cumulative heating and surface friction are key parameters of the Sea Breeze dynamics; (ii) in presence of strong synoptic flow, all scaling laws fail in predicting the Sea Breeze characteristics (the Sea Breeze depth, however being the most accurately predicted); and (iii) the ratio zsb/usb is approximately constant in the Sea Breeze flow.
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Sea-Breeze-Induced Mass Transport over Complex Terrain in South-eastern France: A Case Study
Quarterly Journal of the Royal Meteorological Society, 2006Co-Authors: Sophie Bastin, Philippe DrobinskiAbstract:The structure and evolution of the Sea Breeze in southern France on 25 June 2001 is investigated experimentally and numerically. This study shows how interactions between the Sea Breeze, the synoptic flow and the complex terrain affect the Sea-Breeze structure, and quantifies and discusses the air-mass transport associated with the Sea-Breeze circulation. The analysis of the front propagation and the associated turbulent kinetic energy budget allows four distinct stages of Sea-Breeze front evolution to be identified. Quantification of the horizontal and vertical air-mass fluxes is related to these four stages: the horizontal advection is directly linked to the intensity of the Sea-Breeze flow. Two main mechanisms contribute to the vertical export within the free troposphere: anabatic upslope winds which are intensified by the Sea-Breeze flow and frontogenesis at the Sea-Breeze front which generates turbulence and mixing and upward motion
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the
2006Co-Authors: Rhône Valley, Patricia Delville, Sophie Bastin, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d’Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain M. Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhône Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhône Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Expérience sur Site pour Contraindre les Modèles de Pollution Atmosphérique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhône Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhône Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhône Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhône Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhône Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
Christian Werner - One of the best experts on this subject based on the ideXlab platform.
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the
2006Co-Authors: Rhône Valley, Patricia Delville, Sophie Bastin, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d’Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain M. Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhône Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhône Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Expérience sur Site pour Contraindre les Modèles de Pollution Atmosphérique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhône Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhône Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhône Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhône Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhône Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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Impact of the Rhone and Durance valleys on Sea-Breeze Circulation in the Marseille Area
Atmospheric Research, 2004Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Alain Dabas, Christian WernerAbstract:Sea-Breeze dynamics in the Marseille area, in the south of France, is investigated in the framework of the ESCOMPTE experiment conducted during summer 2001 in order to evaluate the role of thermal circulations on pollutant transport and ventilation. Under particular attention in this paper is the Sea-Breeze channelling by the broad Rhone valley and the narrow Durance valley, both oriented nearly-north–south, i.e., perpendicular to the coastline, and its possible impact on the Sea-Breeze penetration, intensity and depth, which are key information for air pollution issues. One situation of slight synoptic pressure gradient leading to a northerly flow in the Rhone valley (25 June 2001) and one situation of a weak onshore prevailing synoptic wind (26 June 2001) are compared. The impact of the Rhone and Durance valleys on the Sea-Breeze dynamics on these two typical days is generalized to the whole ESCOMPTE observing period. The present study shows by combining simple scaling analysis with wind data from meteorological surface stations and Doppler lidars that (i) the Durance valley always affects the Sea Breeze by accelerating the flow. A consequence is that the Durance valley contributes to weaken the temperature gradient along the valley and thus the Sea-Breeze circulation. In some cases, the acceleration of the channelled flow in the Durance valley suppresses the Sea-Breeze flow by temperature gradient inhibition; (ii) the Rhone valley does not generally affect the Sea Breeze significantly. However, if the Sea Breeze is combined with an onshore flow, it leads to further penetration inland and intensification of the low-level southerly flow. In this situation, lateral constriction may accelerate the Sea Breeze. Simple scaling analysis suggests that Saint Paul (44.35°N, about 100 km from the coastline) is the lower limit where Sea Breeze can be affected by the Rhone valley. These conclusions have implications in air quality topics as channelled Sea Breeze may advect far inland pollutants which may be incorporated into long-range transport, particularly in the Durance valley.
Oliver Reitebuch - One of the best experts on this subject based on the ideXlab platform.
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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Variability of three-dimensional Sea Breeze structure in southern France: observations and evaluation of empirical scaling laws
Ann. Geophys., 2006Co-Authors: Ph. Drobinski, Abhimanyu Dabas, Patricia Delville, Sophie Bastin, Oliver ReitebuchAbstract:Sea-Breeze dynamics in southern France is investigated using an airborne Doppler lidar, a meteorological surface station network and radiosoundings, in the framework of the ESCOMPTE experiment conducted during summer 2001 in order to evaluate the role of thermal circulations on pollutant transport and ventilation. The airborne Doppler lidar WIND contributed to three-dimensional (3-D) mapping of the Sea Breeze circulation in an unprecedented way. The data allow access to the onshore and offshore Sea Breeze extents (xsb), and to the Sea Breeze depth (zsb) and intensity (usb). They also show that the return flow of the Sea Breeze circulation is very seldom seen in this area due to (i) the presence of a systematic non zero background wind, and (ii) the 3-D structure of the Sea Breeze caused by the complex coastline shape and topography. A thorough analysis is conducted on the impact of the two main valleys (Rhône and Durance valleys) affecting the Sea Breeze circulation in the area.\n\nFinally, this dataset also allows an evaluation of the existing scaling laws used to derive the Sea Breeze intensity, depth and horizontal extent. The main results of this study are that (i) latitude, cumulative heating and surface friction are key parameters of the Sea Breeze dynamics; (ii) in presence of strong synoptic flow, all scaling laws fail in predicting the Sea Breeze characteristics (the Sea Breeze depth, however being the most accurately predicted); and (iii) the ratio zsb/usb is approximately constant in the Sea Breeze flow.
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the
2006Co-Authors: Rhône Valley, Patricia Delville, Sophie Bastin, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d’Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain M. Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhône Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhône Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Expérience sur Site pour Contraindre les Modèles de Pollution Atmosphérique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhône Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhône Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhône Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhône Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhône Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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Impact of the Rhone and Durance valleys on Sea-Breeze Circulation in the Marseille Area
Atmospheric Research, 2004Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Alain Dabas, Christian WernerAbstract:Sea-Breeze dynamics in the Marseille area, in the south of France, is investigated in the framework of the ESCOMPTE experiment conducted during summer 2001 in order to evaluate the role of thermal circulations on pollutant transport and ventilation. Under particular attention in this paper is the Sea-Breeze channelling by the broad Rhone valley and the narrow Durance valley, both oriented nearly-north–south, i.e., perpendicular to the coastline, and its possible impact on the Sea-Breeze penetration, intensity and depth, which are key information for air pollution issues. One situation of slight synoptic pressure gradient leading to a northerly flow in the Rhone valley (25 June 2001) and one situation of a weak onshore prevailing synoptic wind (26 June 2001) are compared. The impact of the Rhone and Durance valleys on the Sea-Breeze dynamics on these two typical days is generalized to the whole ESCOMPTE observing period. The present study shows by combining simple scaling analysis with wind data from meteorological surface stations and Doppler lidars that (i) the Durance valley always affects the Sea Breeze by accelerating the flow. A consequence is that the Durance valley contributes to weaken the temperature gradient along the valley and thus the Sea-Breeze circulation. In some cases, the acceleration of the channelled flow in the Durance valley suppresses the Sea-Breeze flow by temperature gradient inhibition; (ii) the Rhone valley does not generally affect the Sea Breeze significantly. However, if the Sea Breeze is combined with an onshore flow, it leads to further penetration inland and intensification of the low-level southerly flow. In this situation, lateral constriction may accelerate the Sea Breeze. Simple scaling analysis suggests that Saint Paul (44.35°N, about 100 km from the coastline) is the lower limit where Sea Breeze can be affected by the Rhone valley. These conclusions have implications in air quality topics as channelled Sea Breeze may advect far inland pollutants which may be incorporated into long-range transport, particularly in the Durance valley.
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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Variability of three-dimensional Sea Breeze structure in southern France: observations and evaluation of empirical scaling laws
Ann. Geophys., 2006Co-Authors: Ph. Drobinski, Abhimanyu Dabas, Patricia Delville, Sophie Bastin, Oliver ReitebuchAbstract:Sea-Breeze dynamics in southern France is investigated using an airborne Doppler lidar, a meteorological surface station network and radiosoundings, in the framework of the ESCOMPTE experiment conducted during summer 2001 in order to evaluate the role of thermal circulations on pollutant transport and ventilation. The airborne Doppler lidar WIND contributed to three-dimensional (3-D) mapping of the Sea Breeze circulation in an unprecedented way. The data allow access to the onshore and offshore Sea Breeze extents (xsb), and to the Sea Breeze depth (zsb) and intensity (usb). They also show that the return flow of the Sea Breeze circulation is very seldom seen in this area due to (i) the presence of a systematic non zero background wind, and (ii) the 3-D structure of the Sea Breeze caused by the complex coastline shape and topography. A thorough analysis is conducted on the impact of the two main valleys (Rhône and Durance valleys) affecting the Sea Breeze circulation in the area.\n\nFinally, this dataset also allows an evaluation of the existing scaling laws used to derive the Sea Breeze intensity, depth and horizontal extent. The main results of this study are that (i) latitude, cumulative heating and surface friction are key parameters of the Sea Breeze dynamics; (ii) in presence of strong synoptic flow, all scaling laws fail in predicting the Sea Breeze characteristics (the Sea Breeze depth, however being the most accurately predicted); and (iii) the ratio zsb/usb is approximately constant in the Sea Breeze flow.
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the
2006Co-Authors: Rhône Valley, Patricia Delville, Sophie Bastin, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhone Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhone Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Experience sur Site pour Contraindre les Modeles de Pollution Atmospherique et de Transport d’Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhone Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhone Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhone Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhone Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhone Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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On the Interaction between Sea Breeze and Summer Mistral at the Exit of the Rhône Valley
Monthly Weather Review, 2006Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Vincent Guénard, Jean-luc Caccia, Bernard Campistron, Alain M. Dabas, Christian WernerAbstract:The three-dimensional structure and dynamics of the combination of the Sea Breeze and the mistral at the Rhône Valley exit, in southeastern France, have been investigated experimentally and numerically on 22 June 2001. The mistral refers to a severe northerly wind that develops along the Rhône Valley. The exit of this valley is located near the Mediterranean Sea where Sea-Breeze circulation often develops. The Sea Breeze and the mistral coexist this day because of the weakness of this mistral event. The event was documented in the framework of the Expérience sur Site pour Contraindre les Modèles de Pollution Atmosphérique et de Transport d'Emissions (ESCOMPTE) field experiment. Several important data sources are used (airborne Doppler lidar, UHF wind profilers, radiosoundings, and surface stations) as well as nonhydrostatic mesoscale simulations. This paper examines the various mechanisms that drive the time and spatial variability of the mistral and the Sea Breeze in various regions of the Rhône Valley. In the morning, the Sea Breeze penetrates inland near the western side of the Rhône Valley then moves back because of the reinforcement of the mistral flow caused by the deepening of the leeward surface low due to convection at noon. At midday, the Sea Breeze penetrates inland in the middle of the Rhône Valley only. In contrast to pure Sea-Breeze episodes when the Sea Breeze can extend inland over a horizontal range of more than 150 km, the presence of the mistral prevents the Sea Breeze from penetrating more than 40 km onshore. In the late afternoon, the Sea Breeze reaches the eastern side of the Rhône Valley but over a smaller horizontal range because of higher local topography and because the mistral is more intense in this part of the Rhône Valley. The situations of Sea-Breeze–mistral interactions can have a severe impact on regional air quality. Indeed, the southerly Sea Breeze, which advects toward the countryside the pollutants emitted from the large coastal city of Marseille, France, and its industrialized suburbs, cannot penetrate far inland because of the mistral blowing in the opposite direction. This leads to the stagnation of the pollutants near the area of emission that is also the most densely inhabited area of the region (over one million inhabitants).
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Impact of the Rhone and Durance valleys on Sea-Breeze Circulation in the Marseille Area
Atmospheric Research, 2004Co-Authors: Sophie Bastin, Patricia Delville, Oliver Reitebuch, Philippe Drobinski, Alain Dabas, Christian WernerAbstract:Sea-Breeze dynamics in the Marseille area, in the south of France, is investigated in the framework of the ESCOMPTE experiment conducted during summer 2001 in order to evaluate the role of thermal circulations on pollutant transport and ventilation. Under particular attention in this paper is the Sea-Breeze channelling by the broad Rhone valley and the narrow Durance valley, both oriented nearly-north–south, i.e., perpendicular to the coastline, and its possible impact on the Sea-Breeze penetration, intensity and depth, which are key information for air pollution issues. One situation of slight synoptic pressure gradient leading to a northerly flow in the Rhone valley (25 June 2001) and one situation of a weak onshore prevailing synoptic wind (26 June 2001) are compared. The impact of the Rhone and Durance valleys on the Sea-Breeze dynamics on these two typical days is generalized to the whole ESCOMPTE observing period. The present study shows by combining simple scaling analysis with wind data from meteorological surface stations and Doppler lidars that (i) the Durance valley always affects the Sea Breeze by accelerating the flow. A consequence is that the Durance valley contributes to weaken the temperature gradient along the valley and thus the Sea-Breeze circulation. In some cases, the acceleration of the channelled flow in the Durance valley suppresses the Sea-Breeze flow by temperature gradient inhibition; (ii) the Rhone valley does not generally affect the Sea Breeze significantly. However, if the Sea Breeze is combined with an onshore flow, it leads to further penetration inland and intensification of the low-level southerly flow. In this situation, lateral constriction may accelerate the Sea Breeze. Simple scaling analysis suggests that Saint Paul (44.35°N, about 100 km from the coastline) is the lower limit where Sea Breeze can be affected by the Rhone valley. These conclusions have implications in air quality topics as channelled Sea Breeze may advect far inland pollutants which may be incorporated into long-range transport, particularly in the Durance valley.
