NCSU Flux Tower Data Level b1: QC checks applied to measurements Data Format: CSV Description: See "instrument descripotion Site: Houston, TX; Tracking Aerosol Convection interactions ExpeRiment (HOU) Location: Houston, TX; AMF1 (main site for TRACER) Facility Code: M1 Category: Aerosol Properties Data Type: PI Data Source Instrument/Data: Sonic Anemometer, 3 Condensation Particle Counters, 1 SP2, 1 POPS Start Date: 2022-06-01 End Date: 2022-9-26 Contact PI: Markus Petters (mdpetter@ncsu.edu) Funding Source: DOE ASR award US Department of Energy, Office of Science, Biological and Environment Research (grant no. DE-SC 0021074) instrument description "The NCSU flux tower was located next to the AMF sampling pad. The flux tower consisted of a 10 m telescoping tower. Mounted at the top of the tower was a sonic anemometer (RM Young 8000) and a Krypton Hygrometer. A sample line (¼” conductive tubing) and communication line was laid to a trailer located underneath and slightly adjacent to the tower. The sample line brought aerosol inside the trailer at 4.5 L min-1, where it was distributed between 3 CPCs (TSI 3776c, Dc ~ 2.5 nm, TSI 3771, Dc ~10nm, and TSI 3772, Dc ~40 nm) with different size cuts. Also sampling was a printed particle optical spectrometer (POPS) and a single particle soot photometer (SP2). Please contact mdpetter@ncsu.edu for further information.” alignement tests "The data from the tower were acquired using a custom data acquisition system that logged time at UTC. Due to transport from the top of the tower into the trailer, the three CPCs and the POPS have slightly different arrival times. Alignment tests were performed to pass particles through tubing of approximately similar length than the tubing to the top of the tower. A 3-way valve, one side open to the room and one side capped with a HEPA filter was placed at the end of the tubing. Toggling the valve provides information about the net instrument response time and relative alignment. For each filter toggle, t50 values corresponding to the time where concentration went from 0-50% or 100-50% was calculated and averaged over several filter toggles. The lagging data streams were shifted such that the particle time series are all aligned in the data file. Filter tests were not removed from the data and occurred during the times noted below. For days with no filter test mean t50 values were used to correct for delay. The SP2 sampled on its own clock, which was subject to additional drift compared to the other particle sensors (3 CPCs and 1 POPS). Note that no correction was made to align to the data in time with the sonic anemometer." Filter test times: "06022022: 13:55-13:59 06062022: 16:38-16:43 06082022: 14:00-14:03 06102022: 14:41-14:45 06132022: 14:00-14:04 06152022: 13:45-13:49 06172022: 14:55-14:59 06182022: 16:22-16:25 06202022: 13:28-13:31 06212022: 14:33-14:35 06232022: 14:30-14:34 06272022: 14:25-14:28 06292022: 13:51-13:53 07012022: 14:40-14:44 07042022: 14:48-14:51 07062022: 12:57-13:02 07082022: 15:42-15:45 07112022: 14:32-14:35 07132022: 14:55-15:00 07162022: 15:29-15:34 07202022: 14:14-14:17 07252022: 13:42-13:47 08012022: 15:36-15:39 08022022: 13:32-13:37 08052022: 15:15-15:21 08092022: 14:23-14:36 08152022: 14:42-14:55 08172022: 14:14-14:18 08262022: 16:29-16:34 08302022: 14:27-14:32 09012022: 14:20-14:23 09032022: 14:06-14:09 09052022: 14:29-14:33 09102022: 13:50-13:55 09152022: 13:50-13:55 09182022: 14:25-14:30 09202022: 14:24-14:30 09262022: 15:53-15:59" SP2 calibration times: 07262022: 14:36-17:02 09262022: 16:16-18:39 quality assurance and quality control "Data during general instrument maintenance, data outages during storms, and suspected instrument malfunction are removed. Examples of instrument malfunction are CPC flag errors or concentration errors due to water build up in the CPC." POPS is configured by its own manufacturer into 16 bins for particle size distributions double diameter_pops_bounds(diameter_opc, bound) ; diameter_pops_bounds:units = "nm" ; diameter_pops_bounds:longname = "POPS diameter bin boundaries calibrated using ammonium sulfate at NCSU" ; diameter_pops_bounds_minimum = "158, 175, 194, 215, 238, 292, 381, 500, 592, 820, 1290, 1674, 2090, 2917, 3795, 4923" diameter_pops_bounds_maximum = "175, 194, 215, 238, 292, 381, 500, 592, 820, 1290, 1674, 2090, 2917, 3795, 4923, 6393" variables timestamp ; longname = "NCSU tower time stamp, in ISO 8601 standard form, UTC Timestamp since 2022-06-0100:00:00.0"; unit = "YYYY-MM-ddHH:MM:SS.s" comment = nothing u ; longname = "u component of the wind of sonic anemometer of NCSU tower." unit = "m s-1" missing value = "" comment = "u,v,w,T are from an RM Young 8000 sonic anemometer mounted at the top of a 10 m telescoping tower" v ; longname = "v component of the wind of sonic anemometer of NCSU tower." unit = "m s-1" missing value = "" comment = nothing w ; longname = "w component of the wind of sonic anemometer of NCSU tower." unit = "m s-1" missing value = "" comment = nothing T ; longname = "Tempertaure component of sonic anemometer of NCSU tower." unit = "Celsius" missing value = "" comment = nothing KH2Or ; longname = "Water vapor concentration measured by a krypton hygrometer." unit = "g m-3" missing value = "" comment = "The KH2O data acquisition suffered from low voltage readings that result in frequent Inf values. However, fluxes computed from the KH2O compare well with the ECOR, when sufficient data were available. Therefore the data is included here" conc3776c ; longname = "Total number concentration of condensation particle counter 3776c." unit = "cm-3" missing value = "" comment = "CPC 3776c was operated with a condenser temperature at 10 degrees Celsius, and a saturation temperature at 39 degrees Celsius. The CPC data were upsampled from 1Hz to 10 Hz to fit the file format." conc3771 ; longname = "Total number concentration of condensation particle counter 3771" unit = "cm-3" missing value = "" comment = "CPC 3771 was operated with a condenser temperature at 22 degrees Celsius, and a saturation temperature at 39 degrees Celsius. The CPC data were upsampled from 1Hz to 10 Hz to fit the file format." conc3772 ; longname = "Total number concentration of condensation particle counter 3772" unit = "cm-3" missing value = "" comment = "CPC 3772 was operated at reduced condenser temperature, corresponding to a lower size cut of 40 nm; condenser temperature at 34 degrees Celsius, saturation temperature at 39 degrees Celsius. The CPC data were upsampled from 1Hz to 10 Hz to fit the file format" sdTotal ; longname = "Derived total number concentration from POPS Digitizer-PH concentration." unit = "cm-3" missing value = "" comment = "All 'sd' data were reprocessed from single particle output to 10Hz using the method described in Kasparoglu et al. (2022, https://doi.org/10.5194/amt-15-5007-2022). The binning is virtually identical to the 16 bin manufacturer output streamed via serial, except for the faster time resolution. The binbounds for channels sd1 to sd16 are given above" sd1 ; longname = "First bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd2 ; longname = "Second bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd3 ; longname = "Third bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd4 ; longname = "Fourth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd5 ; longname = "Fifth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd6 ; longname = "Sixth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd7 ; longname = "Seventh bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd8 ; longname = "Eighth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd9 ; longname = "Ninth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd10 ; longname = "Tenth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd11 ; longname = "Eleventh bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd12 ; longname = "Twelfth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd13 ; longname = "Thirteenth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd14 ; longname = "Fourteenth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd15 ; longname = "Fifteenth bin size distribution derived from the Digitizer-PH." unit = "cm-3" missing value = "" comment = nothing sd16 ; longname = "Sixteenth bin size distribution derived from the Digitizer-PH". unit = "cm-3" missing value = "" comment = nothing sp2scat ; longname = "Scattering particles concentrations detected by the single particle soot photometer (SP2)." unit = "cm-3" missing value = "" comment = "Scattering concentration obtained from the SP2 houskeeping file. Concentrations are resampled from 1Hz to 10Hz to fit the file format." sp2rbc ; longname = "Refractory black carbon (rBC) concentrations detected by the single particle soot photometer (SP2)." unit = "cm-3" missing value = "" comment = "refractory black carbon concentration obtained from the SP2 housekeeping file. Concentrations are resampled from 1Hz to 10Hz to fit the file format." sp2status; longname = "Status of the single particle soot photometer (SP2)." unit = "0" missing value = "" comment = nothing