Accessibility navigation


Atmospheric boundary layer classification with Doppler lidar

Manninen, A. J., Marke, T., Tuononen, M. and O'Connor, E. J. (2018) Atmospheric boundary layer classification with Doppler lidar. Journal of Geophysical Research: Atmospheres, 123 (15). pp. 8172-8189. ISSN 2169-8996

[img]
Preview
Text - Published Version
· Please see our End User Agreement before downloading.

4MB

It is advisable to refer to the publisher's version if you intend to cite from this work. See Guidance on citing.

To link to this item DOI: 10.1029/2017jd028169

Abstract/Summary

We present a method using Doppler lidar data for identifying the main sources of turbulent mixing within the atmospheric boundary layer. The method identifies the presence of turbulence and then assigns a turbulent source by combining several lidar quantities: attenuated backscatter coefficient, vertical velocity skewness, dissipation rate of turbulent kinetic energy, and vector wind shear. Both buoyancy‐driven and shear‐driven situations are identified, and the method operates in both clear‐sky and cloud‐topped conditions, with some reservations in precipitation. To capture the full seasonal cycle, the classification method was applied to more than 1 year of data from two sites, Hyytiälä, Finland, and Jülich, Germany. Analysis showed seasonal variation in the diurnal cycle at both sites; a clear diurnal cycle was observed in spring, summer, and autumn seasons, but due to their respective latitudes, a weaker cycle in winter at Jülich, and almost non‐existent at Hyytiälä. Additionally, there are significant contributions from sources other than convective mixing, with cloud‐driven mixing being observed even within the first 500 m above ground. Also evident is the considerable amount of nocturnal mixing within the lowest 500 m at both sites, especially during the winter. The presence of a low‐level jet was often detected when sources of nocturnal mixing were diagnosed as wind shear. The classification scheme and the climatology extracted from the classification provide insight into the processes responsible for mixing within the atmospheric boundary layer, how variable in space and time these can be, and how they vary with location.

Item Type:Article
Refereed:Yes
Divisions:Faculty of Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
ID Code:78693
Publisher:American Geophysical Union

Downloads

Downloads per month over past year

University Staff: Request a correction | Centaur Editors: Update this record

Page navigation