NOAA PSL OttDisdrometerStats BrushCreek for SLASH

Data Format for DisdrometerOTTParsivel Stats

 
    

Header: InstrumentModel (SN: SerialNumber) Time (YYJJJHH): StatsFileBeginTime[2-digit-Year;3-digit-DayOfYear;2-digit-Hour] UTC

Data Field 1:     Begin time of the accumulation/averaging period in UTC

                  MM  = minute
                  SS  = second
                  mmm = millisecond

Data Field 2:     End time of the accumulation/averaging period in UTC

                  MM  = minute
                  SS  = second
                  mmm = millisecond
Data Field 3-34:  Partical distribution (count) binned by ClassNumber

                  ClassNumber according to volume-equivalent diameter:
                  
                  ClassNumber  ClassAverage(mm) ClassSpread(mm)
                       1            0.062            0.125
                       2            0.187            0.125
                       3            0.312            0.125
                       4            0.437            0.125
                       5            0.562            0.125
                       6            0.687            0.125
                       7            0.812            0.125
                       8            0.937            0.125
                       9            1.062            0.125
                       10           1.187            0.125
                       11           1.375            0.250
                       12           1.625            0.250
                       13           1.875            0.250
                       14           2.125            0.250
                       15           2.375            0.250
                       16           2.750            0.500
                       17           3.250            0.500
                       18           3.750            0.500
                       19           4.250            0.500
                       20           4.750            0.500
                       21           5.500            1.000
                       22           6.500            1.000
                       23           7.500            1.000
                       24           8.500            1.000
                       25           9.500            1.000
                       26           11.000           2.000
                       27           13.000           2.000
                       28           15.000           2.000
                       29           17.000           2.000
                       30           19.000           2.000
                       31           21.500           3.000
                       32           24.500           3.000
                       
                       Note: Class 1 and Class 2 are limits and are not evaluated 
                             at the current time in measurements using the Parsivel 
                             since they are outside the measurement range of the
                             device.
                             
Data Field 35-37:  Data acquisition software quality control

                   Blackout = number of data samples excluded during PC clock synchronization
                   Good     = number of samples that passed the quality control checks, as performed by the data acquisition software
                   Bad      = number of samples that failed the quality control checks, as performed by the data acquisition software
                   
Data Field 38-42:  Precipitation statistics

                   NumParticle   = total number of detected particles
                   Rate(mm/h)    = rain rate; units: millimeter per hour
                   Amount(mm)    = interval rain accumulation ; units: millimeter
                   AmountSum(mm) = event rain accumulation; units: millimeter
                   Z(dB)         = radar refelctivity factor; units: decibel
                   
Data Field 43-48:  Laser status

                   NumError     = number of sample instances that were reported as dirty, very dirty, or damaged 
                   Dirty        = laser protective glass is dirty, but measurements are still possible
                   VeryDirty    = laser protective glass is dirty, partially covered; no further usable measurements are possible
                   Damaged      = laser damaged
                   SignalAvg    = average signal amplitude of the laser strip; unitless
                   SignalStdDev = standard deviation of the signal amplitude of the laser strip; unitless
                   

Data Field 49-54:  Sensor status

                   TempAvg(C)           = average sensor temperature; units: Celsius
                   TempStdDev(C)        = standard deviation of the sensor temperature; units: Celsius
                   VoltAvg(V)           = sensor power supply voltage; units: Volts
                   VoltStdDev(V)        = standard deviation of the sensor power supply voltage; units: Volts
                   HeatCurrentAvg(A)    = average heating system current; units: Amps
                   HeatCurrentStdDev(A) = standard deviation of the heating system current; units: Amps
                   
Data Field 55-58:  Precipitation partitioning

                   NumRain   = number of particles detected as rain
                   NumNoRain = number of particles detected not as rain
                   NumAmbig  = number of particles detected as ambiguous
                   Type      = precipitation type (1=rain; 2=mixed; 3=snow)
                   
                   Note: NumRain, NumNoRain, and NumAmbig counts are determined based on size-velocity masking described in:
                   
                         Yuter, S. E., D. E. Kingsmill, L. B. Nance, and M. Loffler-Mang, 2006: Observations of precipitation
                         size and fall speed characteristics within coexisting rain and wet snow. J. Appl. Meteor.,45, 1450-1464.
                         
                         Precipitation type is determined by RainFraction thresholds, where
                         
                         RainFraction = NumRain / (NumRain + NumNoRain), and
                         
                         Type = 1 (rain)  for RainFraction > 0.95
                         Type = 3 (snow)  for RainFraction < 0.05
                         Type = 2 (mixed) for RainFraction >= 0.05 and RainFraction <= 0.95
                         
                         Erroneous particle-size-velocity measurements (and thereby derived precipitation types) can occur at 
                         higher wind speeds (as low as ~ 6 m/s), as documented in:

                         Neiman, P.J., D.J. Gottas, A.B. White, W.R. Schneider, and D. Bright, 2018: A Real-Time Online Data 
                         Product that Automatically Detects Easterly Gap Flow Events and Precipitation Type in the Columbia 
                         River Gorge.  J. Atmos. Oceanic Technol., 35, 2037-2052.

                         Less conservative RainFraction thresholds for precipitation typing were also explored in Neiman et al.