We have developed a laboratory system that provides mass spectra of individual particles, roughly 20 microns in diameter, after they have been levitated in an electric field. Measured evaporation of polyethylene glycol particles was found to agree with a kinetic model. The system can be used to study fundamental chemical and physical processes involving particles that are difficult to isolate and study with other techniques, and hence improve our understanding of atmospheric particles. Hide

A unique CIMS utilizing a multi-species neg. ion chemistry was designed to measure peroxides and organic acids throughout the troposphere from an aircraft. Prior CIMS have used a single reagent ion and the multi-ion approach has the potential to be a significant step forward, although one with analytical risk. Here, a chemical kinetics numerical model is presented which simulates its past water vapor and pressure dependence, providing a test-bed to characterize its use in future environments. Hide

We present SWING-UAV, an atmospheric observation system based on a compact scanning spectrometer (SWING) mounted on an Unmanned Aerial Vehicle (UAV). SWING-UAV was operated in the exhaust plume of a power plant in Romania in September 2014, during the AROMAT campaign. SWING quantified the NO₂ emitted by the plant and the water vapor content in the boundary layer, in agreement with ancillary data. The system appears in particular promising to study emissions in rural areas. Hide

This work focuses on making unambiguous measurements of Arctic cloud phase and assessing those measurements within the context of cloud radiative effects. It is found that effects related to lidar data recording systems can cause retrieval ambiguities that alter the interpretation of cloud phase in as much as 30 % of the available data. This misinterpretation of cloud phase data can cause a misinterpretation of the effect of cloud phase on the surface radiation budget by as much as 10 % to 30 %. Hide

A new generation of the Infrared Atmospheric Sounding Interferometer (IASI) sounders, whose highly accurate measurements are commonly used in environment applications, has been already designed: IASI New Generation (IASI-NG). A database of IASI and IASI-NG simulated observations was built to set a common framework for future impact studies. This first study showed the IASI-NG benefit with an improvement of the temperature retrievals along all the atmosphere and a lower benefit for the humidity. Hide

Data from the high-sensitivity CALIOP cloud lidar onboard the CALIPSO satellite has been used to evaluate cloud amounts estimated from satellite imagery and, specifically, from the climate dataset CLARA-A2. The main purpose has been to study the limit of how thin clouds that can be detected efficiently (i.e., detected at the 50 % level) in CLARA-A2 data and how this limit varies globally. The study revealed very large geographical differences in the cloud detection efficiency. Hide

Prior satellite comparisons of bispectral and polarimetric cloud droplet size retrievals exhibited systematic biases. However, similar airborne instrument retrievals have been found to be quite similar to one another. This study explains this discrepancy in terms of differing sensitivity to vertical profile, as well as spatial and angular resolution. This is accomplished by using a satellite retrieval simulator – an LES cloud model coupled to radiative transfer and retrieval algorithms. Hide

In the first part, we revise selected findings regarding utilization of Global Positioning System radio occultation density profiles for analysis of internal gravity waves. The results show that previously published results are valid only for one specific data version. Using radiosonde profiles, we also analyze nonhydrostatic component in temperature profiles. The last part presents detailed study on the utilization of density profiles for characterization of the wave field stability. Hide

The estimation of precipitable water vapour (W) content is of great interest in both meteorological and climatological studies. Sun-photometers allowed the development of W automatic estimations with high temporal resolution. A new methodology, based on the hypothesis that the calibration parameters characterizing the atmospheric transmittance are dependent on vertical profiles of temperature, air pressure and moisture typical of each measurement site, has been presented providing good results. Hide

This paper presents a novel statistical data selection method for CO₂ measurements at elevated mountain measuring stations. It provides insights on how data processing techniques are critical for measurements and data analyses. By applying different methods on atmospheric CO₂ of various mountain stations, our method appears to be a good option as a generalized approach with improved comparability, which is important for researches on station characteristics or data analyses between stations. Hide

Estimating aerosol layer height in the atmosphere from satellite data in the oxygen A-band (758–770 nm) over land is challenging over land, since the surface is generally very bright in this wavelength region. This paper discusses an interplay between the surface and the atmosphere in their contributions to the top of atmosphere reflectance spectrum and the consequent biases obtained while estimating aerosol layer height, using synthetic data and real data from the GOME-2 satellite instrument. Hide

This manuscript presents an inter-comparison of state of the art online and in situ particle sampling techniques connected to proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS). Collection and vaporization of aerosol combined with soft ionization mass spectrometry offers the advantage of detailed chemical characterization of SOA species. The benefits of these techniques are highlighted through their consistency in providing the chemical composition of biogenic SOA. Hide

We present a first analysis of UV/VIS spectral measurements obtained with the Spectrolite Breadboard Instrument (developed by TNO, The Netherlands) during the AROMAPEX campaign held in Berlin in April 2016 (campaign supported by ESA and EUFAR). This new sensor was used to measure air pollution in the form of tropospheric NO₂ columns. The study focuses specifically on the retrieval of surface reflectances, an important intermediate step towards the final product. Hide

In this study, we use an all-sky stereo camera network to perform geolocation of individual elements of a cloud field. This allows to track individual clouds, estimate their morphological characteristics and their evolution in real-time. Furthermore, this allows to use cloud geolocation for cloud airborne measurements. For example, in the case of instrumented UAVs, the GPS coordinates of the target cloud may be communicated in real-time to the autopilot. Hide

The Ozone Mapping and Profiler Suite Limb Profiler measures scattered sunlight which is then inverted to obtain vertical profiles of ozone in the atmosphere. We have developed a new algorithm for inverting the data which is better suited for areas with large horizontal ozone gradients, such as the polar vortex. Data from the full currently 5 year mission has been processed and is publicly available. Hide

Annual emissions of trace gases requires knowledge of the emissions throughout the day and year. Unfortunately emissions into the surface boundary layer during calm nights are rarely measured. During such conditions surface layer concentrations of carbon dioxide (CO₂) and nitrous oxide (N₂O) often accumulate in the surface boundary layer and the time rate of change of this accumulation was used to estimate emissions. Results showed this approach to be reasonable. Hide

The hotplate precipitation gauge has potential to solve some problems with conventional precipitation gauge measurements, especially for snowfall. This paper extents the seminal published work (Rasmussen et al., 2011). We picked the journal Atmospheric Measurement Techniques over Atmospheric and Oceanic Technology because we want an open review. We assert that the precipitation rate algorithm we have developed for the hotplate is an improvement over that previously published. Hide

PHIPS-HALO is a novel aircraft instrument for cloud research. It combines microscopic imaging of single cloud particles with the measurement of their spacial light scattering properties. The knowledge of how atmospheric ice particles in clouds scatter visible light is important for improving future climate models. Hide

In this work, we evaluated a source of black carbon aerosol generated by ultrasonic spray which shows good performance in our experiments. It has good feasibility in the BC concentrations range of 0–200 μg m⁻³. This generator can be used as a standard source for black carbon monitoring in atmosphere. Hide

This paper verifies and corrects the Ozone Mapping and Profiler Suite (OMPS) Nadir Mapper (NM) Level 1B v2.0 measurements to retrieve reliable ozone profile and tropospheric ozone using an optimal estimation inversion with the fitting window of 302.5–340 nm. We apply "soft calibration" and "common mode correction" to OMPS radiances to eliminate systematic errors in the fitting residuals and derive random-noise measurement errors accounting for both OMPS radiances and forward model calculation. Hide

The affordability and small size of low-cost particle sensors makes them attractive for air pollution experiments that require multiple instruments, or take place in hard to access locations or low income countries. For any sensor to be useful, their accuracy and precision needs to be known. We evaluate the Alphasense OPC-N2 for monitoring airborne particles at typical UK urban background sites. The devices were found to be accurate provided they are correctly calibrated. Hide

We present a novel automated enclosure for protecting solar-tracking atmospheric instruments. It has been deployed in central Munich for greenhouse gas monitoring for one year and withstood all critical weather conditions, including rain, storm, and snow. The enclosure leads to a fully automated measurement system, which collects data whenever possible without any human interaction. It provides the fundament for a long-term greenhouse gas monitoring sensor network. Hide