Data of Fluorescent Aerosol Particles during the Pallas Cloud Experiment 2022

Overview: This data set contains number concentrations and number size distributions of total aerosol particles (TAPs), fluorescent aerosol particles (FAPs) and highly fluorescent aerosol particles (HFAPs) of diameter 0.5 to 30 µm (optical equivalent diameter) obtained by a Wideband Integrated Bioaerosol Sensor 5/NEO (Droplet Measurement Technologies) during the Pallas Cloud Experiment 2022 (PaCE22) campaign in the sub Arctic region of Finish Lapland. The instrument was operated between 17.09.2022 17:00 UTC and 13.12.2022 21:00 UTC at Sammaltunturi Station (67.9733°N 24.1157°E) at 564 m above sea level in the Pallas Atmosphere-Ecosystem Supersite and was connected to a heated total suspended particles (TSP) inlet.

Instrument description: The WIBS samples air with a sample flow rate of 0.3 L/min and uses a 635 nm diode laser to measure the size of single particles between 0.5 and 30 µm and to trigger two xenon lamps with excitation wavelengths of 280 nm and 370 nm. Fluorescence emission intensity is measured in two emission windows of 310 - 400 nm and 420 - 650 nm resulting in three main fluorescence channels: FL1 (excitation 280 nm and emission 310 – 400 nm), FL2 (excitation 280 nm and emission 420 - 650 nm) and FL3 (excitation 370 nm and emission 420 - 650 nm). A particle is considered as fluorescent, if it exceeds the three sigma fluorescence threshold (forced trigger intensity plus three standard deviations) in any channel (FAP). A particle is considered highly fluorescent if it exceeds the nine sigma fluorescence threshold (forced trigger intensity plus nine standard deviations) in any channel (HFAP). Both FAPs and HFAPs are split into 10 types of fluorescent particles each, using the Perring nomenclature (Perring et al., 2015): (H)FAP_ A (FL1 only),  (H)FAP_ B (FL2 only), (H)FAP_ C (FL3 only), (H)FAP_ AB (FL1 and FL2 only), (H)FAP_ AC (FL1 and FL3 only), (H)FAP_ BC(FL2 and FL3 only) and  (H)FAP_ ABC (FL1 and FL2 and FL3), (H)FAP_ FL1 (A+AB+AC+ABC), (H)FAP_ FL2(B+AB+BC+BC) and (H)FAP_ FL3 (C+AC+BC+ABC). 

The files are separated by date (in UTC) and are named the following: TUW.WIBS_N.b1.yyyyMMdd.hhmm.csv. The data file processing level is b1. Quality control checks were applied and missing data points or those with bad values were set to -9999.9.

References: Perring et al., “Airborne observations of regional variation in fluorescent aerosol across the United States,” J Geophys Res-Atmos, vol. 120, Art. no. 3, 2015.