1. First year of Rayleigh lidar measurements of middle atmosphere temperatures above davis, Antarctica
- Author
-
Klekociuk, A.R., Lambert, M.M., Vincent, R.A., and Dowdy, A.J.
- Subjects
- *
STRATOSPHERE , *TEMPERATURE , *MESOSPHERE - Abstract
We report,the first high spatial resolution measurements of the annual variation of temperatures in the stratosphere and lower mesosphere obtained using lidar from a site near the Antarctic Circle. The observations were made using a zenith-oriented Rayleigh backscatter lidar on 77 days between February 2001 and March 2002 at Davis, Antarctica (68.6°S, 78.0°E). Daily average temperature profiles with 1km vertical resolution were retrieved using the standard Rayleigh inversion method. The lidar temperatures were validated through comparison with a variety of observational and model data which included radiosonde measurements, satellite profiles, and meterorological analyses at various altitudes between approximately 30km (the top of the stratospheric aerosol layer) and 60km. Comparison of the lidar temperatures with the MSISE-90 model revealed some significant differences. Between the stratopause and the upper limit of the measurements (65km), monthly average temperatures from March to June and during September were warmer than MSISE-90 by up to 20K. Comparison with previous lidar measurements at South Pole (Pan et al., 2002) and McMurdo (Di Donfrancesco et al., 1996) suggests that stratopause region temperatures near midwinter over Antarctica may be more uniform than predicted by the MSIS model. Between 30km altitude and the stratopause, average temperatures from December to March and during July were cooler than the model (by an average of 5K). The October and November averages were warmer than the model (by up to 15K) below approximately 40km, and cooler than the model (by up to 10K) towards the stratopause. Temperature fluctuations associated with planetary wave activity were observed during late autumn (10K amplitude) and spring (up to 25K amplitude). The spring anomaly coincided with the development of a dominant zonal wavenumber 1 disturbance in the mid-stratosphere temperature field that was quasi-stationary in longitude near Davis. This feature appeared to have a vertical wavelength on the order of 50–60km. [Copyright &y& Elsevier]
- Published
- 2003
- Full Text
- View/download PDF