Winds and temperatures of the Arctic middle atmosphere during January measured by Doppler lidar

Abstract

Abstract. We present an extensive data set of simultaneous temperature and wind measurements in the Arctic middle atmosphere. It consists of more than 300 h of Doppler Rayleigh lidar observations obtained during three January seasons (2012, 2014, and 2015) and covers the altitude range from 30 km up to about 85 km. The data set reveals large yearto-year variations in monthly mean temperatures and winds, which in 2012 are affected by a sudden stratospheric warming. The temporal evolution of winds and temperatures after that warming are studied over a period of 2 weeks, showing an elevated stratopause and the reformation of the polar vortex. The monthly mean temperatures and winds are compared to data extracted from the Integrated Forecast System of the European Centre for Medium-Range Weather Forecasts (ECMWF) and the Horizontal Wind Model (HWM07). Lidar and ECMWF data show good agreement of mean zonal and meridional winds below ≈ 55 km altitude, but we also find mean temperature, zonal wind, and meridional wind differences of up to 20 K, 20 m s −1 , and 5 m s −1 , respectively. Differences between lidar observations and HWM07 data are up to 30 m s −1 . From the fluctuations of temperatures and winds within single nights we extract the potential and kinetic gravity wave energy density (GWED) per unit mass. It shows that the kinetic GWED is typically 5 to 10 times larger than the potential GWED, the total GWED increases with altitude with a scale height of ≈ 16 km. Since temporal fluctuations of winds and temperatures are underestimated in ECMWF, the total GWED is underestimated as well by a factor of 3-10 above 50 km altitude. Similarly, we estimate the energy density per unit mass for largescale waves (LWED) from the fluctuations of nightly mean temperatures and winds. The total LWED is roughly constant with altitude. The ratio of kinetic to potential LWED varies with altitude over 2 orders of magnitude. LWEDs from ECMWF data show results similar to the lidar data. From the comparison of GWED and LWED, it follows that largescale waves carry about 2 to 5 times more energy than gravity waves.

Does Strong Tropospheric Forcing Cause Large‐Amplitude Mesospheric Gravity Waves? A DEEPWAVE Case Study

“…Shorter waves with smaller amplitudes as they appear in the observations below 40 km are not resolved. Yet the amplitude of the temperature perturbations is underestimated by the IFS by a factor of up to about 7, in agreement with previous findings, for example, Hildebrand et al () and Le Pichon et al ().…”

Doppler lidar at Observatoire de Haute-Provence for wind profiling up to 75 km altitude: performance evaluation and observations

“…While the necessity of high-resolution (< 1 km) wind profiling of USLM region is well recognized (e.g., Meriwether and Gerrard, 2004;Dörnbrack et al, 2017); presently, very few instruments with such capacity are operated on a regular or quasi-regular basis. These are Doppler lidars at Arctic Lidar Observatory for Middle Atmospheric Research (ALO-MAR) in northern Norway (Baumgarten, 2010;Hildebrand et al, 2017), LiWind lidar at high-altitude Maido observatory at Réunion island (Baray et al, 2013;Khaykin et al, 2018) and LIOvent lidar at Observatoire de Haute-Provence (OHP), where the pioneering lidar measurements of wind up to 50 km altitude were conducted by Chanin et al (1989).…”

Experimental Calibration of the Overlap Factor for the Pulsed Atmospheric Lidar by Employing a Collocated Scheimpflug Lidar

“…Conventional atmospheric pulsed lidar technique, based on the time-of-flight principle, has been widely developed for atmospheric aerosol remote sensing [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. International lidar networks have also been established for routine observation of atmospheric aerosols [15][16][17][18][19].…”