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Eubrewnet Documentation

codes:calibration

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.
- Input: a complete list of input arguments is provided next, but we strongly recommed to use the web interface at https://rbcce.aemet.es/eubrewnet/caldata/langley to access this function
`brewerid`

: see Brewerid in common inputs`date`

: see Date in common inputs`enddate`

: see Enddate in common inputs`format`

: see Format`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; if checking a mic step which does not correspond to the cal step, it's also recommended to pass the ozone absorption coefficient specific to that mic step using the`urlconfig`

option, see below. Individual observations (not summaries) are used in all cases unless`use_summaries`

is selected, see below.`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)`minairmass`

: airmass minimum in`etc`

calculations (defaults to 1.70 if the option is not passed in the url)`maxairmass`

: airmass maximum in`etc`

calculations (defaults to 3.75 if the option is not passed in the url)`minobs`

: minimum number of observations (either individual observations or summaries) in the half-day to perform the Langley in`etc`

calculations (default value: 25). Note by default all the`data`

functions are configured to return individual observations, but see`use_summaries`

below`filters_minairmass`

: airmass minimum in`filters`

calculations (defaults to 1 if the option is not passed in the url)`filters_maxairmass`

: airmass maximum in`filters`

calculations (defaults to 5 if the option is not passed in the url)`filters_minobs`

: minimum number of observations in the half-day to perform the Langley in`filters`

calculations (default value: 15)`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)`minrsquared`

: don't accept the langley results if the r^{2}of the fits are below this value (default: 0.999)`residuals_filtering`

: do each fit twice, using the residuals of the first to remove observations whose residual is larger than 1.5*std(residuals)`use_summaries`

: if passed as an option, use summaries instead of individual observations for o3l15 and o3l15v2 data. Note the default values for`minobs`

and`filter_minobs`

(25 and 15, respectively) are provided as a guide for calculations with individual observations, the user must set suitable values (eg, 5 for`minobs`

) if`use_summaries`

is passed.`urlconfig`

: allows setting the configuration's parameters, overriding the values in Eubrewnet's database. For example, to set a value of 0.4 for the ozone absorption coefficient, add`&urlconfig&o3o3rate=0.4`

to the url, and to set specific values for the filter corrections add`&urlconfig&fc=1,2,3,4,5`

`debug`

: include debug output. As of 2023-06-29, this returns four additional vectorial fields, 'airmass', 'ms9', 'filt', and 'solartime', with the raw data used in the half-day langley fit.

- Output:
`date`

: date and time of each half-day langley, morning langleys correspond to 00 time, and afternoon ones, to 12`etc`

: calculated ETC`o3xabs`

: calculated ozone multiplied by the ozone absorption coefficient`rsquared`

: r^{2}of the langley fit`nobs`

: number of observations used in the fit`stdo3`

: standard deviation of the half-day ozone`meano3`

: mean ozone of the half-day`filter_corr_3`

,`filter_corr_4`

,`filter_corr_5`

: ETC filter corrections, either calculated in a`filters`

run or supplied passing`&urlconfig&fc=1,2,3,4,5`

in the url`info`

: a brief description of the calculation performed

- Function:
`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
- Input:
`brewerid`

: see Brewerid in common inputs`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`enddate`

: see Enddate in common inputs. If not specified, the current date is used.`format`

: see Format`maxminutes`

: maximum difference in minutes between consecutive measurements, default value: 15`airmass`

: maximum airmass between consecutive measurements, default value: 0.1

- Output:
`config_f1_cor`

,`config_f2_cor`

,`config_f3_cor`

,`config_f4_cor`

,`config_f5_cor`

: ETC filter corrections set in the configuration at Eubrewnet`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`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`calc_f01_nobs`

,`calc_f12_nobs`

,`calc_f23_nobs`

,`calc_f34_nobs`

,`calc_f45_nobs`

: number of near simultaneous observations with the indicated filters

- Function:
`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.
- Input:
`brewerid`

: see Brewerid in common inputs`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`enddate`

: see Enddate in common inputs. If not specified, the current date is used.`format`

: see Format`maxminutes`

: maximum difference in minutes between consecutive measurements, default value: 15`airmass`

: maximum airmass between consecutive measurements, default value: 0.1

- Output:
`previous_gmt`

: date and time of the first measurement in the pair`gmt`

: date and time of the second measurement`previous_airmass`

: airmass of the first measurement`airmass`

: airmass of the second measurement`previous_filt`

: filter position for the first measurement`filt`

: filter position for the second measurement`previous_o3_l1`

: level 1 ozone for the first measurement`o3_l1`

: level 1 ozone for the second measurement`configdate`

: date of the operative configuration`o3o3rate`

: ozone absorption coefficient`fcor`

: filter correction`fchange`

: a single string with both filter positions

- Function:
`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.
- Input:
`brewerid`

: see Brewerid in common inputs`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`enddate`

: see Enddate in common inputs. If not specified, the current date is used.`format`

: see Format

- Output:
`config_f1_cor`

,`config_f2_cor`

,`config_f3_cor`

,`config_f4_cor`

,`config_f5_cor`

: ETC filter corrections set in the configuration at Eubrewnet`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`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`calc_nobs`

: number of measurements in the FIOAVG file

- Function:
`TempCoef`

- Description: This function analyses the temperature sensitivity of SL measurements.
- Input:
`brewerid`

: see Brewerid in common inputs`date`

: see Date in common inputs`enddate`

: see Enddate in common inputs`format`

: see Format`tc`

: if we pass the tc parameter with no value, the fit is done with the SL measurements corrected using the temperature coefficients from the operational setup on Eubrewnet. If we pass six values separated by commas, the fit is done with the corrected SL measurements using these values as temperature coefficients. If the tc parameter is omitted, no temperature correction is applied to the SL measurements.`tmin`

: all data below tmin are removed.`tmax`

: all data above tmax are removed.`alpha`

: Outliers can be removed by giving the alpha parameter a value greater than zero. In this case, after performing the linear regression, all measures whose residuals are greater than the standard deviation of all residuals multiplied by the alpha factor will be removed, and the linear regression will be repeated. This process is repeated iteratively until all values are below this threshold.

- Output: the following fields are included in the output:
`channel`

: Brewer measurement channels in the ozone position next to R5 and R6.`a`

: intercept value for the linear regression.`sa`

: standard error of the intercept of the linear regression.`b`

: slope value for the linear regression.`sb`

: standard error of the slope of the linear regression.`r2`

: R-squared of the linear regression.

- Function:
`SC`

- Description: Returns SC measurements from B file. It adds the temperature of the last HG test made before measurement
- Inputs:
`brewerid`

: see Brewerid in common inputs`date`

: see Date in common inputs`enddate`

: see Enddate in common inputs`format`

: see Format

- Output: SC measurements with extra field:
`temp`

: Temperature from the last made HG before each SC measurement

- Function:
`SCO3`

- Description: Same as SC above with additional information (O3, ms9, longitude, …). A specific micrometer step can be also selected using
`&step=XXX`

. Note by default the ozone will be calculated with the ozone absorption coefficient stored in the operative configuration, which corresponds to the cal step. An ozone absorption coefficient specific for the requested mic step can be passed using the`urlconfig`

method: add e.g.`&urlconfig&o3o3rate=0.4`

to the url - Inputs:
`brewerid`

: see Brewerid in common inputs`date`

: see Date in common inputs`enddate`

: see Enddate in common inputs`format`

: see Format

- Output: SC measurements with additional fields, including:
`temp`

: Temperature from the last made HG before each SC measurement`O3`

: ozone`ms9`

: ms9 double ratio

- Function:
`CI`

or`CJ`

- Description: Return the data from the CI (forward scan) or CJ (forward and backward scans) lamp tests. For CJ, the two scans are shown as two measurements with close but different times.
- Input:
`brewerid`

: see Brewerid in common inputs`date`

: see Date in common inputs`enddate`

: see Enddate in common inputs`format`

: see Format`lamp`

: optional, allowed values are`b1`

and`b2`

, used to select only data with the`b1`

(Hg) or`b2`

(Standard) lamp

- Output: standard output plus other fields, including
`gmt`

: time of the first wavelength measured – the shortest for the CI and CJ forward scan, and the longest for the CJ backward.`mmmm_l`

: time in minutes of the measurement of wavelength`l`

, where`l = 2865, 2870, … 3630`

`raw_counts_l`

: raw counts of wavelength`l`

`counts_per_second_l`

: counts/second for wavelength`l`

`lamp`

: either`b1`

(Hg) or`b2`

(Standard)

- Debug output: if
`&debug`

is passed in the url, two extra fields are included in the output:`lamp_time`

: time at which the lamp was switched on`lamp_co`

: comment from the B file stating which lamp was switched on. This comment corresponds to the most recent in a search on all the comments containing the keywords`b1`

or`b2`

in the B file in the 20 minutes before the first measurement in the CI/CJ

- Function:
`CZ`

- Description: Return the data from the CZ lamp tests. Because in this test the wavelengths are defined by the Brewer operator, Eubrewnet's output is different than in the case of the CI/CJ tests. In particular, the
`l`

in fields such as`mmmm_l`

is now just a numerical index from 0 to 149, and the wavelengths are shown in the new`wavelengths_l`

fields - Input: same as for the CI and CJ functions, see above
- Output: the output is quite similar to that of the CI and CJ functions, the main difference being that the
`_l`

suffix is now a numerical index instead of a wavelength. There are also some new fields:`wavelength_l`

: wavelength in nm corresponding to the l-th measurement`fwpos1`

and`fwpos2`

: filter wheel positions`startwv`

and`finalwv`

: initial and final wavelengths

- Function:
`NI`

- Description: Return the data from the NI responsivity tests.
- Input:
`brewerid`

: see Brewerid in common inputs`date`

: see Date in common inputs`enddate`

: see Enddate in common inputs`format`

: see Format

- Output: besides the usual
`brewerid`

,`gmt`

,`lat`

, … output, some other fields returned include`mmmm`

: minutes since 00:00`wavelength`

: wavelength measured`fwpos1`

and`fwpos2`

: filter wheel positions`rawcountssml`

: raw counts for the slit mask`l`

position, where`l=0,1,…,7`

- Functions:
`HS`

and`HL`

- Description: Return the data from the short (2950 – 2984 Å) and long (3331 – 3351 Å) wavelength-range Mercury lamp tests
- Input:
`brewerid`

: see Brewerid in common inputs`date`

: see Date in common inputs`enddate`

: see Enddate in common inputs`format`

: see Format

- Output: besides the usual
`brewerid`

,`gmt`

,`lat`

, … output, some other fields returned include`mmmm`

: minutes since 00:00`wavelength`

: wavelength measured`fwpos1`

and`fwpos2`

: filter wheel positions`rawcounts`

: raw counts`countspsecond`

: counts per second

codes/calibration.txt · Last modified: 2023/08/25 08:45 by jlsolano

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