Measurement report: Properties of aerosol and gases in the vertical profile during the LAPSE-RATE campaign

Abstract

Abstract. Unmanned aerial systems (UASs) are increasingly being used as observation platforms for atmospheric applications. The Lower Atmospheric Process Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE) in Alamosa, Colorado, USA, on 14–20 July 2018 investigated and validated different UASs, measurement sensors and setup configurations. Flight teams from the Finnish Meteorological Institute (FMI) and Kansas State University (KSU) participated in LAPSE-RATE to measure and investigate properties of aerosol particles and gases in the lower atmosphere. During the experiment, the performance of different UAS configurations were investigated and confirmed to operate reliably, resulting in a scientifically sound observational dataset. As an example, concentration of aerosols – including two new particle formation events, CO2 and water vapor, and meteorological parameters in the atmospheric vertical profile were measured during the short experiment. Such observations characterizing atmospheric phenomena of this specific environment would have not been possible in any other way and, thus, demonstrate the power of UASs as new, promising tools in atmospheric and environmental research.

Aerosol particle characteristics measured in the United Arab Emirates and their response to mixing in the boundary layer

“…Our explanation for the correlation between the starting time of boundary layer growth and the start of NPF events is that precursor gases from elevated levels are mixed down to the surface and initiate an NPF event at the surface or that the NPF event is initiated aloft, which has been observed by several studies (Größ et al, 2018;Lampilahti et al, 2021;Brus et al, 2021), and the newly formed particles are then measured at the surface once they are entrained within the growing boundary layer.…”

Temperature and pressure effects on the performance of the portable TSI 3007 condensation particle counter: Implications on ground and aerial observations

“…The performance of this CPC was assessed by Hämeri et al (2002) in laboratory constant-temperature/pressure conditions. Since then, it has been employed in numerous studies where outdoor measurements have been carried out with manned hot-air balloons (e.g., Laakso et al, 2007), unmanned tethered balloons (e.g., Chen et al, 2018;Samad et al, 2020, Brus et al, 2021Creamean et al, 2021), and unmanned aerial vehicles (e.g., Altstädter et al, 2015;Altstädter et al, 2018;Lampert et al, 2020). It should be noted here that the detection efficiency of CPCs can be affected by the measurement conditions as these can in principle affect both the temperature difference/window between the saturator and the condenser (Hermann & Wiedensohler, 2001), as well as the position of this window in the temperature space (Barmpounis et al, 2018).…”

An extensive data set for in situ microphysical characterization of low-level clouds in a Finnish sub-Arctic site

“…Three general approaches were used in previous studies of cloud microphysical properties: in situ sampling through airborne measurements by aircraft (e.g., Heymsfield et al, 2011;Craig et al, 2014;Petäjä et al, 2016;Nguyen et al, 2021) and recently by unmanned aerial systems (UASs) (e.g., Girdwood et al, 2020;Brus et al, 2021;Harrison et al, 2021), in situ sampling by using laboratory cloud chambers (e.g., Möhler et al, 2003;Stratmann et al, 2004;Nichman et al, 2017;Doulgeris et al, 2018), and in situ ground-based measurements (e.g., Guyot et al, 2015;Lloyd et al, 2015;Lowenthal et al, 2019;Doulgeris et al, 2020). In situ airborne and ground measurements (Wandinger et al, 2018) using cloud spectrometers are considered fundamental as they offer instrumental access to individual hydrometeors within a sampling volume.…”