Atmospheric Measurement Techniques (May 2021)
Evaluation of the new DWD ozone and temperature lidar during the Hohenpeißenberg Ozone Profiling Study (HOPS) and comparison of results with previous NDACC campaigns
Abstract
A newly upgraded German Weather Service (DWD) ozone and temperature lidar (HOH) located at the Hohenpeißenberg Meteorological Observatory (47.8∘ N, 11.0∘ E) has been evaluated through comparison with the travelling standard lidar operated by NASA's Goddard Space Flight Center (NASA GSFC Stratospheric Ozone (STROZ) lidar), satellite overpasses from the Microwave Limb Sounder (MLS), the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER), the Ozone Mapping and Profiler Suite (OMPS), meteorological radiosondes launched from Munich (65 km northeast), and locally launched ozonesondes. The “blind” evaluation was conducted under the framework of the Network for the Detection of Atmospheric Composition Change (NDACC) using 10 clear nights of measurements in 2018 and 2019. The campaign, referred to as the Hohenpeißenberg Ozone Profiling Study (HOPS), was conducted within the larger context of NDACC validation activities for European lidar stations. There was good agreement between all ozone lidar measurements in the range of 15 to 41 km with relative differences between co-located ozone profiles of less than ±10 %. Differences in the measured ozone number densities between the lidars and the locally launched ozone sondes were also generally less than 5 % below 30 km. The satellite ozone profiles demonstrated some differences with respect to the ground-based lidars which are due to sampling differences and geophysical variation. Both the original and new DWD lidars continue to meet the NDACC standard for lidar ozone profiles by exceeding 3 % accuracy between 16.5 and 43 km. Temperature differences for all instruments were less than ±5 K below 60 km, with larger differences present in the lidar–satellite comparisons above this region. Temperature differences between the DWD lidars met the NDACC accuracy requirements of ±1 K between 17 and 78 km. A unique cross-comparison between the HOPS campaign and a similar, recent campaign at Observatoire de Haute-Provence (Lidar Validation NDACC Experiment; LAVANDE) allowed for an investigation into potential biases in the NASA-STROZ reference lidar. The reference lidar may slightly underestimate ozone number densities above 43 km with respect to the French and German NDACC lidars. Below 20 km, the reference lidar temperatures profiles are 5 to 10 K cooler than the temperatures which are reported by the other instruments.