5:15 PM - 7:15 PM
[AAS06-P11] Analysis of layered structures observed in the tropical to subtropical troposphere
Keywords:troposphere, layered structure, gravity wave, advection
In the troposphere, vertically layered structures with their thicknesses ranging from several hundred meters to several kilometers, characterized by variations in water vapor and ozone concentrations, are occasionally observed. The cause of those layered structures has long been discussed, and they were attributed to the advection of different air masses originating from different regions sometimes related to atmospheric waves (gravity and Rossby waves). However, because of their smallness in scale, it has been difficult to obtain direct evidence of their formation process e.g., from reanalysis data.
In this study, we use radiosonde data as well as the latest high-resolution vertical reanalysis data (model-level data of ERA5) to reveal the formation process of the layered structures. Radiosonde data obtained by YMC campaign observations made from May 27, 2021 to June 3, 2021 in a wide latitudinal range of 30°N to 1°N are analyzed.
The analysis of radiosonde data showed that there was a negative correlation between ozone mixing ratio and relative humidity, indicating the mixture of the airmass from the marine boundary layer and the one from the stratosphere. On the other hand, ozone mixing ratio and potential temperature anomalies were generally positively correlated, suggesting the influence of gravity wave-induced vertical advection. A further analysis of the ERA5 data shows that a subtropical disturbance contributes to the formation, while its detailed process is unclear. We plan to conduct isentropic analysis and discuss the three-dimensional formation process of the layered structures in more detail on the day of the presentation.
In this study, we use radiosonde data as well as the latest high-resolution vertical reanalysis data (model-level data of ERA5) to reveal the formation process of the layered structures. Radiosonde data obtained by YMC campaign observations made from May 27, 2021 to June 3, 2021 in a wide latitudinal range of 30°N to 1°N are analyzed.
The analysis of radiosonde data showed that there was a negative correlation between ozone mixing ratio and relative humidity, indicating the mixture of the airmass from the marine boundary layer and the one from the stratosphere. On the other hand, ozone mixing ratio and potential temperature anomalies were generally positively correlated, suggesting the influence of gravity wave-induced vertical advection. A further analysis of the ERA5 data shows that a subtropical disturbance contributes to the formation, while its detailed process is unclear. We plan to conduct isentropic analysis and discuss the three-dimensional formation process of the layered structures in more detail on the day of the presentation.