Drone-based meteorological observations up to the tropopause – a concept study Atmospheric Measurement Techniques DOI 10.5194/amt-16-3739-2023 11 August 2023 The first atmospheric soundings with an electrically powered small uncrewed aircraft system (UAS) up to an altitude of 10 km are presented and assessed for quality, revealing the potential to augment atmospheric observations and fill observation gaps for numerical weather prediction. This is significant because of the need for high-resolution meteorological data, in particular in remote areas with limited in situ measurements, and for reference data for satellite measurement calibration. Read more
The EarthCARE mission – science and system overview Atmospheric Measurement Techniques DOI 10.5194/amt-16-3581-2023 9 August 2023 The EarthCARE satellite is due for launch in 2024. It includes four scientific instruments to measure global vertical profiles of aerosols, clouds and precipitation properties together with radiative fluxes and derived heating rates. The mission’s scientific requirements, the satellite and the ground segment are described. In particular, the four scientific instruments and their performance are described at the level of detail required by mission data users. Read more
Diurnal carbon monoxide observed from a geostationary infrared hyperspectral sounder: first result from GIIRS on board FengYun-4B Atmospheric Measurement Techniques DOI 10.5194/amt-16-3059-2023 5 July 2023 Observations from geostationary orbit provide contiguous coverage with a high temporal resolution, representing an important advancement over current low-Earth-orbit instruments. Using measurements from GIIRS on board China’s FengYun satellite, the world’s first geostationary hyperspectral infrared sounder, we showed the first results of diurnal CO in eastern Asia from a geostationary orbit, which will have great potential in improving local and global air quality and climate research. GIIRS on board FengYun-4B">Read more
Applying machine learning to improve the near-real-time products of the Aura Microwave Limb Sounder Atmospheric Measurement Techniques DOI 10.5194/amt-16-2733-2023 21 June 2023 The algorithm that produces the near-real-time data products of the Aura Microwave Limb Sounder has been updated. The new algorithm is based on machine learning techniques and yields data products with much improved accuracy. It is shown that the new algorithm outperforms the previous versions, even when it is trained on only a few years of satellite observations. This confirms the potential of applying machine learning to the near-real-time efforts of other current and future mission concepts. Read more
Evaluation of polarimetric ice microphysical retrievals with OLYMPEX campaign data Atmospheric Measurement Techniques DOI 10.5194/amt-16-2089-2023 10 May 2023 We present an evaluation of current retrieval techniques in the ice phase applied to polarimetric radar measurements with collocated in situ observations of aircraft conducted over the Olympic Mountains, Washington State, during winter 2015. Radar estimates of ice properties agreed most with aircraft observations in regions with pronounced radar signatures, but uncertainties were identified that indicate issues of some retrievals, particularly in warmer temperature regimes. OLYMPEX campaign data">Read more
Influence of ozone and humidity on PTR-MS and GC-MS VOC measurements with and without a Na2S2O3 ozone scrubber Atmospheric Measurement Techniques DOI 10.5194/amt-16-1179-2023 7 April 2023 Atmospheric ozone can induce artefacts in volatile organic compound measurements. Laboratory tests were made using GC-MS and PTR-MS aircraft systems under tropospheric and stratospheric conditions of humidity and ozone, with and without sodium thiosulfate filter scrubbers. Ozone in dry air produces some carbonyls and degrades alkenes. The scrubber lifetime depends on ozone concentration, flow rate and humidity. For the troposphere with scrubber, no significant artefacts were found over 14 d. PTR-MS and GC-MS VOC measurements with and without a Na2S2O3 ozone scrubber">Read more
Atmospheric boundary layer height from ground-based remote sensing: a review of capabilities and limitations Atmospheric Measurement Techniques DOI 10.5194/amt-16-433-2023 3 March 2023 Profile observations of the atmospheric boundary layer now allow for layer heights and characteristics to be derived at high temporal and vertical resolution. With novel high-density ground-based remote-sensing measurement networks emerging, horizontal information content is also increasing. This review summarises the capabilities and limitations of various sensors and retrieval algorithms which need to be considered during the harmonisation of data products for high-impact applications. Read more
Validation of the Aeolus L2B wind product with airborne wind lidar measurements in the polar North Atlantic region and in the tropics Atmospheric Measurement Techniques DOI 10.5194/amt-15-7049-2022 8 February 2023 In August 2018, the first wind lidar Aeolus was launched into space and has since then been providing data of the global wind field. The primary goal of Aeolus was the improvement of numerical weather prediction. To verify the quality of Aeolus wind data, DLR performed four airborne validation campaigns with two wind lidar systems. In this paper, we report on results from the two later campaigns, performed in Iceland and the tropics. Read more
Determination of atmospheric column condensate using active and passive remote sensing technology Atmospheric Measurement Techniques DOI 10.5194/amt-15-3555-2022 29 August 2022 It is necessary to correctly evaluate the amount of cloud water resources in an area. Currently, there is a lack of effective observation methods for atmospheric column condensate evaluation. We propose a method for atmospheric column condensate by combining millimetre cloud radar, lidar and microwave radiometers. The method can realise determination of atmospheric column condensate. The variation of cloud before precipitation is considered, and the atmospheric column is deduced and obtained. Read more
Enhancing MAX-DOAS atmospheric state retrievals by multispectral polarimetry – studies using synthetic data Atmospheric Measurement Techniques DOI 10.5194/amt-15-2077-2022 4 July 2022 MAX-DOAS is a widely used measurement technique for the remote detection of atmospheric aerosol and trace gases. It relies on the analysis of ultra-violet and visible radiation spectra of skylight. To date, information contained in the skylight’s polarisation state has not been utilised. On the basis of synthetic data, we carried out sensitivity analyses to assess the potential of polarimetry for MAX-DOAS applications. MAX-DOAS atmospheric state retrievals by multispectral polarimetry – studies using synthetic data">Read more