This page provides a brief overview of the functions avaliable in Eubrewnet to determine Brewer configuration parameters.

• Function: langley
• Description: Determine the ETC and the ETC filter corrections applying the Langley-plot method to each half day.
• Access function example: https://rbcce-test.aemet.es/eubrewnet/data/cal/langley?brewerid=185&date=2022-04-01&enddate=2022-04-22&format=text
• Input: a complete list of input arguments is provided next, but we strongly recommed to use the web interface at https://rbcce-test.aemet.es/eubrewnet/caldata/langley to access this function
  1. brewerid: see Brewerid in common inputs
  2. date: see Date in common inputs
  3. enddate: see Enddate in common inputs
  4. format: see Format
  5. data: input data used, available options are o3l15 (default if the option is not passed in the url), o3l15v2, o3l1, sco3 for the O3L1.5, O3L1.5V2, O3L1 and sun scan measurements, respectively. For the sco3 option, the step option with the value of the micrometer step must be also passed in the url. Individual observation (not summaries) are used in all cases. Note you can override the default configuration used to process the data in Eubrewnet using the urlconfig method (eg, to pass new ETC filter correction methods add &urlconfig&fc=1,2,3,4,5 to the url)
  6. calc: calculation to perform, available options are etc (Langley-plot with all the data, default option), filters (the Langley-plot fit is done using dummy variables for filters 3, 4, 5, and thus allows to determine the ETC filter correction of those filters with respect to the ETC obtained for the set measurements with filters 0, 1, and 2), and filters_etc (this option performs two fits: first, a filters run to determine the ETC filter corrections, and then an etc calculation using these ETC filter corrections). For etc runs, two different fits are performed: ms9 vs airmass (brewer method) and ms9/airmass vs 1/airmass (dobson method)
  7. minairmass: airmass minimum in etc calculations (defaults to 1.70 if the option is not passed in the url)
  8. maxairmass: airmass maximum in etc calculations (defaults to 3.75 if the option is not passed in the url)
  9. minobs: minimum number of observations in the half-day to perform the Langley in etc calculations (default value: 25)
  10. filters_minairmass: airmass minimum in filters calculations (defaults to 1 if the option is not passed in the url)
  11. filters_maxairmass: airmass maximum in filters calculations (defaults to 5 if the option is not passed in the url)
  12. filters_minobs: minimum number of observations in the half-day to perform the Langley in filters calculations (default value: 15)
  13. maxstdo3: don't perform the langley if the maximum of the standard deviation of the half-day ozone is above this value (default: 2.5)
  14. minrsquared: don't accept the langley results if the r² of the fits are below this value (default: 0.999)
• Output:
  1. date: date and time of each half-day langley, morning langleys correspond to 00 time, and afternoon ones, to 12
  2. etc: calculated ETC
  3. o3xabs: calculated ozone multiplied by the ozone absorption coefficient
  4. rsquared: r² of the langley fit
  5. nobs: number of observations used in the fit
  6. stdo3: standard deviation of the half-day ozone
  7. meano3: mean ozone of the half-day
  8. filter_corr_3,filter_corr_4,filter_corr_5: ETC filter corrections, either calculated in filters run or supplied passing &urlconfig&fc=1,2,3,4,5 in the url
  9. info: a brief description of the calculation performed

• Name: fcor_o3dif
• Description: this function returns the ETC filter corrections (with respect to the mean of filters 1 and 2) as calculated from the ozone differences of near-simultaneous measurements taken with different filters. Mathematically, for two measurements taken with different filters at almost the same airmass μ and with a ΔO3L1 difference in the (uncorrected) ozone, Δfiltercorr=ΔO3L1∗μ∗abscoeff∗10
• Access function example: https://rbcce.aemet.es/eubrewnet/data/cal/fcor_o3dif?brewerid=185&format=text&minutes=15&airmass=0.03&date=2022-01-01&enddate=2022-02-01
• Input:
  1. brewerid: see Brewerid in common inputs
  2. date: see Date in common inputs. If not specified, the calculation will be carried out for all the date ranges between the configurations available in Eubrewnet
  3. enddate: see Enddate in common inputs. If not specified, the current date is used.
  4. format: see Format
  5. maxminutes: maximum difference in minutes between consecutive measurements, default value: 15
  6. airmass: maximum airmass between consecutive measurements, default value: 0.1
• Output:
  1. config_f1_cor, config_f2_cor, config_f3_cor, config_f4_cor , config_f5_cor: ETC filter corrections set in the configuration at Eubrewnet
  2. calc_f1_cor, calc_f2_cor, calc_f3_cor, calc_f4_cor, calc_f5_cor: median of all the ETC filter corrections calculated in the period, referred to the mean of filters 1 and 2
  3. calc_f1_sd, calc_f2_sd, calc_f3_sd, calc_f4_sd, calc_f5_sd: standard deviation of the ETC filter corrections in the period
  4. calc_f01_nobs, calc_f12_nobs, calc_f23_nobs, calc_f34_nobs, calc_f45_nobs: number of near simultaneous observations with the indicated filters

• Name: fcor_o3dif_raw
• Description: this function returns the raw data used in the fcor_o3dif function. That is, it returns Δfiltercorr=ΔO3L1∗μ∗abscoeff∗10 for each pair of measurements, without referring the result to filters 1 and 2 nor calculating any median over a date range.
• Access function example: https://rbcce.aemet.es/eubrewnet/data/cal/fcor_o3dif_raw?brewerid=185&format=text&minutes=15&airmass=0.03&date=2022-01-01&enddate=2022-02-01
• Input:
  1. brewerid: see Brewerid in common inputs
  2. date: see Date in common inputs. If not specified, the calculation will be carried out for all the date ranges between the configurations available in Eubrewnet
  3. enddate: see Enddate in common inputs. If not specified, the current date is used.
  4. format: see Format
  5. maxminutes: maximum difference in minutes between consecutive measurements, default value: 15
  6. airmass: maximum airmass between consecutive measurements, default value: 0.1
• Output:
  1. previous_gmt: date and time of the first measurement in the pair
  2. gmt: date and time of the second measurement
  3. previous_airmass: airmass of the first measurement
  4. airmass: airmass of the second measurement
  5. previous_filt: filter position for the first measurement
  6. filt: filter position for the second measurement
  7. previous_o3_l1: level 1 ozone for the first measurement
  8. o3_l1: level 1 ozone for the second measurement
  9. configdate: date of the operative configuration
  10. o3o3rate: ozone absorption coefficient
  11. fcor: filter correction
  12. fchange: a single string with both filter positions

• Name: fcor_fioavg
• Description: this function returns the ETC filter corrections (with respect to the mean of filters 1 and 2) as calculated from the results of the Brewer filter tests with the standard lamp, as found in the FIOAVG file.
• Access function example: https://rbcce.aemet.es/eubrewnet/data/cal/fcor_fioavg?brewerid=185&format=text&date=2022-01-01&enddate=today
• Input:
  1. brewerid: see Brewerid in common inputs
  2. date: see Date in common inputs. If not specified, the calculation will be carried out for all the date ranges between the configurations available in Eubrewnet
  3. enddate: see Enddate in common inputs. If not specified, the current date is used.
  4. format: see Format
• Output:
  1. config_f1_cor, config_f2_cor, config_f3_cor, config_f4_cor , config_f5_cor: ETC filter corrections set in the configuration at Eubrewnet
  2. calc_f1_cor, calc_f2_cor, calc_f3_cor, calc_f4_cor, calc_f5_cor: median of all the ETC filter corrections calculated in the period, referred to the mean of filters 1 and 2
  3. calc_f1_sd, calc_f2_sd, calc_f3_sd, calc_f4_sd, calc_f5_sd: standard deviation of the ETC filter corrections in the period
  4. calc_nobs: number of measurements in the FIOAVG file