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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. [ABSTRACT FROM AUTHOR]

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 STROZ), 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 München (65 km north-east), 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. This campaign was conducted within the larger context of NDACC validation activities for European lidar stations. The previous 2017-2018 validation campaign took place at the French Observatoire de Haute Provence and and showed a high degree of fidelity between participating instruments. The results are reported in the companion article (Wing et al., 2020). 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 numbers 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. Temperatures 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 lidars met the NDACC accuracy requirements of ±;1 K between 17 and 78 km. The NASA lidar exhibited slightly colder temperatures, between 5 and 10 K, than the other instruments below 20 km and slightly warmer temperatures, 5 to 10 K, above 70 km. These differences are likely due to algorithm initialisation choices and photon count saturation corrections. [ABSTRACT FROM AUTHOR]

A two-part intercomparison campaign was conducted at Observatoire de Haute-Provence (OHP) for the validation of lidar ozone and temperature profiles using the mobile NASA Stratospheric Ozone Lidar (NASA STROZ), satellite overpasses from the Microwave Limb Sounder (MLS), the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER), meteorological radiosondes launched from Nîmes, and locally launched ozonesondes. All the data were submitted and compared "blind", before the group could see results from the other instruments. There was good agreement between all ozone measurements between 20 and 40 km, with differences of generally less than 5 % throughout this region. Below 20 km, SABER and MLS measured significantly more ozone than the lidars or ozonesondes. Temperatures for all lidars were in good agreement between 30 and 60 km, with differences on the order of ±1 to 3 K. Below 30 km, the OHP lidar operating at 532 nm has a significant cool bias due to contamination by aerosols. Systematic, altitude-varying bias up to ±5 K compared to the lidars was found for MLS at many altitudes. SABER temperature profiles are generally closer to the lidar profiles, with up 3 K negative bias near 50 km. Total uncertainty estimates for ozone and temperature appear to be realistic for nearly all systems. However, it does seem that the very low estimated uncertainties of lidars between 30 and 50 km, between 0.1 and 1 K, are not achieved during Lidar Validation Network for the Detection of Atmospheric Composition Change (NDACC) Experiment (LAVANDE). These estimates might have to be increased to 1 to 2 K. [ABSTRACT FROM AUTHOR]

A two-part inter-comparison campaign was conducted at L'Observatoire de Haute Provence (OHP) for the validation of lidar ozone and temperature profiles using the mobile NASA Stratospheric Ozone Lidar (NASA STROZ), satellite overpasses from the Microwave Limb Sounder (MLS), the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER), meteorological radiosondes launched from Nimes, and locally launched ozonesondes. All the data were submitted and compared blind, before the group could see results from the other instruments. There was good agreement between all ozone measurements between 20 and 40 km with differences of generally less than 5 % throughout this region. Below 20 km SABER and MLS measured significantly more ozone than the lidars or ozone sondes. Temperatures for all lidars were in good agreement between 30 and 60 km with differences on the order of ±1 to 3 K. Below 30 km, the OHP lidar operating at 532 nm has a significant cool bias due to contamination by aerosols. Systematic, altitude varying bias up to ±5 K compared to the lidars was found for MLS at many altitudes. SABER temperature profiles are generally closer to the lidar profiles, with up 3 K negative bias near 50 km. Uncertainty estimates for ozone and temperature appear to be realistic for nearly all systems. However, it does seem that the very low estimated uncertainties of lidars between 30 and 50 km, between 0.1 and 1 K, are not achieved during LidAr VAlidation NDacc Experiment (LAVANDE). These estimates might have to be increased to 1 to 2 K. [ABSTRACT FROM AUTHOR]

During a 2-week period in May 2014, the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center Tropospheric Ozone Differential Absorption Lidar (GSFC TROPOZ DIAL) was situated near the NASA Langley Research Center (LaRC) Mobile Ozone Lidar (LMOL) and made simultaneous measurements for a continuous 15-h observation period in which six separate ozonesondes were launched to provide reference ozone profiles. Although each of these campaign-ready lidars has very different transmitter and receiver components, they produced very similar ozone profiles, which were mostly within 10% of each other and the ozonesondes. The observed column averages as compared to the ozonesondes also agree well and are within 8% of each other. A robust uncertainty analysis was performed, and the results indicate that there is no statistically significant systematic bias between the TROPOZ and LMOL instruments. With the extended measurements and ozonesonde launches, this intercomparison has yielded an in-depth evaluation of the precision and accuracy of the two new lidars. This intercomparison is also the first (to the best of the authors' knowledge) reported measurement intercomparison of two ground-based tropospheric ozone lidar systems within the United States. [ABSTRACT FROM AUTHOR]