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O. R. Cooper - One of the best experts on this subject based on the ideXlab platform.
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics, 2006Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbon monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a Lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3?100 ppbv; CO?90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3?200 ppbv; CO?90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement with the maritime development of the cyclone, the chemical composition of the anticyclonic portion of the warm conveyor belt outflow (O3?40 ppbv; CO?85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbon monoxide in the upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents identification of the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed.
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics, 2006Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbone monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3≃100 ppbv; CO≃90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3≃200 ppbv; CO≃90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement to the maritime development of the cyclone, the chemical composition of the anticyclonic part outflow of the warm conveyor belt (O3≃40 ppbv; CO≃85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbone monoxide in upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents to identify the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed Stratosphere-troposphere exchange in a summertime extratropical low: Analysis (PDF Download Available). Available from: https://www.researchgate.net/publication/26637935_Stratosphere-troposphere_exchange_in_a_summertime_extratropical_low_Analysis [accessed Jun 16, 2017].
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics Discussions, 2005Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbone monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3?100 ppbv; CO?90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3?200 ppbv; CO?90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement to the maritime development of the cyclone, the chemical composition of the anticyclonic part outflow of the warm conveyor belt (O3?40 ppbv; CO?85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbone monoxide in upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents to identify the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed.
Jérôme Brioude - One of the best experts on this subject based on the ideXlab platform.
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics, 2006Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbon monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a Lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3?100 ppbv; CO?90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3?200 ppbv; CO?90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement with the maritime development of the cyclone, the chemical composition of the anticyclonic portion of the warm conveyor belt outflow (O3?40 ppbv; CO?85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbon monoxide in the upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents identification of the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed.
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics, 2006Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbone monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3≃100 ppbv; CO≃90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3≃200 ppbv; CO≃90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement to the maritime development of the cyclone, the chemical composition of the anticyclonic part outflow of the warm conveyor belt (O3≃40 ppbv; CO≃85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbone monoxide in upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents to identify the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed Stratosphere-troposphere exchange in a summertime extratropical low: Analysis (PDF Download Available). Available from: https://www.researchgate.net/publication/26637935_Stratosphere-troposphere_exchange_in_a_summertime_extratropical_low_Analysis [accessed Jun 16, 2017].
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics Discussions, 2005Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbone monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3?100 ppbv; CO?90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3?200 ppbv; CO?90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement to the maritime development of the cyclone, the chemical composition of the anticyclonic part outflow of the warm conveyor belt (O3?40 ppbv; CO?85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbone monoxide in upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents to identify the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed.
Jean-pierre Cammas - One of the best experts on this subject based on the ideXlab platform.
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics, 2006Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbon monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a Lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3?100 ppbv; CO?90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3?200 ppbv; CO?90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement with the maritime development of the cyclone, the chemical composition of the anticyclonic portion of the warm conveyor belt outflow (O3?40 ppbv; CO?85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbon monoxide in the upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents identification of the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed.
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics, 2006Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbone monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3≃100 ppbv; CO≃90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3≃200 ppbv; CO≃90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement to the maritime development of the cyclone, the chemical composition of the anticyclonic part outflow of the warm conveyor belt (O3≃40 ppbv; CO≃85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbone monoxide in upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents to identify the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed Stratosphere-troposphere exchange in a summertime extratropical low: Analysis (PDF Download Available). Available from: https://www.researchgate.net/publication/26637935_Stratosphere-troposphere_exchange_in_a_summertime_extratropical_low_Analysis [accessed Jun 16, 2017].
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Stratosphere-troposphere exchange in a summertime extratropical low: analysis
Atmospheric Chemistry and Physics Discussions, 2005Co-Authors: Jérôme Brioude, Jean-pierre Cammas, O. R. CooperAbstract:Ozone and carbone monoxide measurements sampled during two commercial flights in Airstreams of a summertime midlatitude cyclone are analysed with a lagrangian-based study (backward trajectories and a Reverse Domain Filling technique) to gain a comprehensive understanding of transport effects on trace gas distributions. The study demonstrates that summertime cyclones can be associated with deep stratosphere-troposphere transport. A tropopause fold is sampled twice in its life cycle, once in the lower troposphere (O3?100 ppbv; CO?90 ppbv) in the dry Airstream of the cyclone, and again in the upper troposphere (O3?200 ppbv; CO?90 ppbv) on the northern side of the large scale potential vorticity feature associated with baroclinic development. In agreement to the maritime development of the cyclone, the chemical composition of the anticyclonic part outflow of the warm conveyor belt (O3?40 ppbv; CO?85 ppbv) corresponds to the lowest mixing ratios of both ozone and carbone monoxide in upper tropospheric airborne observations. The uncertain degree of confidence of the Lagrangian-based technique applied to a 100 km segment of upper level airborne observations with high ozone (200 ppbv) and relatively low CO (80 ppbv) observed northwest of the cyclone prevents to identify the ozone enrichment process of air parcels embedded in the cyclonic part of the upper level outflow of the warm conveyor belt. Different hypotheses of stratosphere-troposphere exchange are discussed.
Andreas Stohl - One of the best experts on this subject based on the ideXlab platform.
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a 1 year lagrangian climatology of Airstreams in the northern hemisphere troposphere and lowermost stratosphere
Journal of Geophysical Research, 2001Co-Authors: Andreas StohlAbstract:This paper presents a 1-year “climatology” of Airstreams, based on a large number of three-dimensional air parcel trajectories started daily from points on a grid covering the Northern Hemisphere troposphere and lowermost stratosphere. Different types of Airstreams (warm conveyor belts, dry intrusions, stratosphere-to-troposphere flows, and troposphere-to-stratosphere flows) are identified, and their geographical distribution and associated mass fluxes are examined. Warm conveyor belt air parcels, which are deposited in the uppermost troposphere and even the lowermost stratosphere, originate most frequently in the boundary layer over the warm water pools at the eastern seaboards of North America and Asia, close to the worldwide highest anthropogenic emissions. Therefore their chemical characteristics likely range from very clean to highly polluted. Because warm conveyor belts rarely start over Europe, European trace gas emissions have fewer chances of reaching the upper troposphere and lowermost stratosphere with warm conveyor belts than emissions from other densely populated regions. On the other hand, the upper troposphere over Europe frequently receives outflow from warm conveyor belts originating over the North American seaboard. Dry intrusion activity is highest in winter and lowest in summer and shows maxima over western North America and eastern Asia. Deep intrusions from the stratosphere into the lower troposphere are almost nonexistent during the summer. Mass fluxes associated with each of the Airstream types are reported and are an alternative to Eulerian mass flux estimates. All types of Airstreams with strong vertical motions are highly incoherent. Rather than depositing compact air parcels, they stir air masses into a new environment and create filamentary tracer structures.
David M. Schultz - One of the best experts on this subject based on the ideXlab platform.
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Global Climatologies of Fronts, Airmass Boundaries, and Airstream Boundaries: Why the Definition of “Front” Matters
Monthly Weather Review, 2019Co-Authors: Carl M. Thomas, David M. SchultzAbstract:AbstractClimatologies of fronts, airmass boundaries, and Airstream boundaries can be calculated using automated approaches on gridded data. Such approaches may require choices to define a front, in...
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Contraction Rate and Its Relationship to Frontogenesis, the Lyapunov Exponent, Fluid Trapping, and Airstream Boundaries
Monthly Weather Review, 2005Co-Authors: Robert A. Cohen, David M. SchultzAbstract:Although a kinematic framework for diagnosing frontogenesis exists in the form of the Petterssen frontogenesis function and its vector generalization, a similar framework for diagnosing Airstream boundaries (e.g., drylines, lee troughs) has not been constructed. This paper presents such a framework, beginning with a kinematic expression for the rate of change of the separation vector between two adjacent air parcels. The maximum growth rate of the separation vector is called the instantaneous dilatation rate and its orientation is called the axis of dilatation. Similarly, a maximum decay rate is called the instantaneous contraction rate and its orientation is called the axis of contraction. These expressions are related to the vector frontogenesis function, in that the growth rate of the separation vector corresponds with the scalar frontogenesis function, and the rotation rate of the separation vector corresponds with the rotational component of the vector frontogenesis function. Because vorticity can rotate air-parcel pairs out of regions of deformation, the instantaneous dilatation and contraction rates and axes may not be appropriate diagnostics of Airstream boundaries for fluid flows in general. Rather, the growth rate and orientation of an Airstream boundary may correspond better to the so-called asymptotic contraction rate and the asymptotic axis of dilatation, respectively. Expressions for the asymptotic dilatation and contraction rates, as well as their orientations, the asymptotic dilatation and contraction axes, are derived. The asymptotic dilatation rate is related to the Lyapunov exponent for the flow. In addition, a fluid-trapping diagnostic is derived to distinguish among adjacent parcels being pulled apart, being pushed together, or trapped in an eddy. Finally, these diagnostics are applied to simple, idealized, steady-state flows and a nonsteady idealized vortex in nondivergent, diffluent flow to show their utility for determining the character of air-parcel trajectories and Airstream boundaries.