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instructions_to_the_participants_2008

Instructions_to_the_Participants_2008

= Before Calibration Campaing =

Pre calibration

#With your instrument bring an version of average files (AVG) , AP,DT,RS,HG,SL,MI , better if you send by mail this files to the organization before the campaign. #Take a list of the important events of your instrument log book, problems with your instrument, change of lams…etc #Collect your previous calibrations (ICF, UVR files) and if you use the software O3Brewer bring your current and previous configuration files (O3brewer.i01,….) #For the UV bring the updated calibration and the QL or XL files. #If you have new electronics brewer, bring a copy of the EPROM configuration

Travel

Before the transport of your instrument is recommended to perform a set of test, to assurance than your instrument is not changing during the transport. This test will be repeat after the travel and examine for possible changes. This is important for backward calibration.  Also is recommended to perform an external lamp uv calibration to see any change on the instrument responsivity
The recommended test are:
 HPHGSLDTRSAPPOB1w1CIb2w1CZ (NI( ?))   (unattended)
 FI (1/2hour) FWTEST2, SH(?)           (user assisted)
 HPHGQLTU                              (Ultraviolet)  

Packing /Unpacking instructions

BREWER SPECTROMETER PACKING INSTRUCTIONS

Packing Instructions

  1. Affix a piece of cardboard over the zenith prism window with a tape such as electrical or masking tape.
  2. Install the UV dome protector cap onto the UV dome. Tape can be used to affix an appropriately sized cardboard box over the dome if the protector cap is not available–but this is risky and not a long-term solution.
  3. Remove the Brewer cover. Manually rotate the zenith prism down to the lamps using the brass gear in the zenith drive system.
  4. Use masking tape to affix a piece of foam on the top part of the split-gear in the zenith drive assembly to prevent the split gear from being damaged by impacting against the Brewer cover (sometimes Brewers are transported upside-down despite all of the “UP” labels placed on the packing case).
  5. Insert a thick piece of foam under the spectrometer case, between the spectrometer case and the heat sink assembly.
  6. Place a piece of foam over the control panel (iris and entrance slit viewer panel) so that the Brewer cover presses down on the foreoptics and spectrometer. This will also help to ensure that movement is restricted during shipping.
  7. Place a container of desiccant inside the instrument–usually over the secondary power supply. Ensure that the container cannot open during shipping–a few elastic bands are helpful if a plastic dish with a re-sealable lid is used. Also ensure that the desiccant in the drying tube is fresh.
  8. Replace the Brewer cover.

Unpacking Instructions

  1. Remove the Brewer cover and the piece of foam over the control panel.
  2. Remove the piece of foam under the spectrometer case, between the spectrometer case and the heat sink assembly.
  3. Remove foam on the top part of the split-gear in the zenith drive.
  4. Ensure that the dessicant in both the desiccant tube and the desiccant container are fresh.
  5. Replace the Brewer cover.
  6. Remove the piece of cardboard over the zenith prism window.
  7. Remove the UV dome protector cap on the UV dome after the Brewer has been installed onto the tracker.

SUN-SCAN calibration

Before the campaign put several sun-scan test, SC, on your operating schedule at airmasses between 2-3.5. The objective is to have almost seven good sc between 500-1200 DU of ozone slant path (ozone concentration X airmass ). You have to put an hphg test before and after the sun-scan. The measure is only valid is the sky is clear during the measurement.

= Principals Investigator and Participating instruments =

Every participating instrument are associated to a Principal Investigator (PI). The PI are considered de responsible to send the data to the coordinators . The list of the PI are and instrument are shown bellow

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The first day is dedicated to installation and setup, the next two-three days (depending on the weather conditions) the intercomparison will be blind with a predefined schedule for all brewer participants. The next two-three days the schedule can be interrupted to perform calibration maintenance (Dispersion, Laser scans, etc). The blind days for UV (see later) are also blind days for the ozone and can be used as final calibration the first days will be considered as initial calibration.

= Campaing Schedule =

For the brewers the campaign start on day 21 to day 29 when the Dobson-Brewer campaign start, everybody interested can stay until the Saturday 2.

The first day is dedicated to installation and setup, the next two-three days (depending on the weather conditions) the intercomparison will be blind with a predefined schedule for all brewer participants. The next two-three days the schedule can be interrupted to perform calibration maintenance (Dispersion, Laser scans, etc).

The blind days for UV (see later) are also blind days for the ozone and can be used as final calibration the first days will be considered as initial calibration.

Campaing Program

3rd RBCC-E Calibration Campaign, LKO, Arosa (Switzerland). July, 20 to August, 01 2008

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- Adjustments & Maintenance

- Calculation of calibration constant

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-ETC for aerosols transfer

Instruments not interested on the Dobson-Brewer comparison can pack the instruments

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The 3rd RBCC-E Calibration Campaign, LKO, Arosa (Switzerland). July, 20 to August, 01 2008: Note: Click on Agenda tab below to see a detailed events list. style="left:0"|title=Third Iberonesia Comparison Events|content= <googlecalendar>ugkutdcrtn6k0ia7cmfaofbnds@group.calendar.google.com</googlecalendar>

Blind Intercomparison

You have to avoid any manipulation of the instrument which could produce a change on the calibration. The interchange of data between participants is forbidden.

= Ozone =

Ozone calibration Schedule

For the calibration the main priority is to have as much as possible direct sun measurements but also is recommended to use the routines already present on the operational schedules of the stations, this include zenith sky measurements, focused sun and global uv ozone measurements and ultraviolet measurements.

On this 3rd campaign we use the synchronized schedules, the program developed by Alexaner Cede were used at SAUNA campaigns http://fmiarc.fmi.fi/SAUNA and is adapted for the Huelva campaign. The schedules produced assure the synchronization of the measures on different types of brewers. There is two main groups, the uv extended range brewers 290-360 nm (MK-III and most of the MK-IV) and the uv short range (290-325) brewers. The schedules are based in groups of measurements in solar zenith angle ranges (Table 1), the measures in the same group must be last the same for different types of brewer (Table 2).

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Due physical limitations of the quartz window, in most of the brewers, the direct sun is only possible for sza angles above 80º. Below this angle zenith sky, focused sun (for sza >85) and global uv scan are also possible. This is the reason to divide the schedules in four sza angles below 92 to 85, from 85 to 80 , 85 to 75 and above 75. In addition there are two special ranges, a range before and after the start of measurements for test and noon for measurements performed around noon. For the big part of the campaign, sza> 75º, (around 9 hours) there are three possibilities normal, normal with SL and normal with Sun-Scan test. The time consuming Sun-Scan is scheduled for airmass around 1.5,2 and 2.5, three per day. And also three SL are scheduled during the day and two more on the night

Table 4 Mesurements groups

  # 1  92-85     zenith sky measurements + focused sun
  # 2  85-80     zenith sky focused sun, global uv measurements
  # 3  80-75     Start of DS observations, end of focused sun
  # 4  >75       Normal operational  measures  DS, ZS and UV
  # 5  >75       Normal operational plus Standard lamp
  # 6  >75       Normal operational plus Sun Scan
  # 7            Beginning and end of the day
  # 8            noon measurements

Table 5 Mesurements groups

G sza range Short UV range (290-325 nm) Extended UV (290-360 nm)

  1 92-85  tdpdzszszszsufb1fzfzhgzs   	         tpdzszszszsuxhpb1fzfzhgck  
  2 85-80  tdpdzsgifzb1ufhgzsgifzzsgigib1ufhgck   tdpdzsgifzzsgifzzsgifzuxhpb1fzfzhgck
  3 80-75  tdpddsdsdsufb1dshgdsb2zssldsdsgidsfv   tdpddsdsdsuxhpb1dshgb2zssldsdsgidsfv   
  4 75 >   tdpddsdsdsufb1dshgdsdszsdsgidsdszsds   tdpddsdsdsuxhpb1dshgdszsdsgidsdszsds   
  5  or    tdpddsdsdsufb1dshgdsb2zssldsdsgidsfv   tdpddsdsdsuxhpb1dshgb2zssldsdsgidsfv
  6  or    tdpddsdsdsufb1dshgdsscb1fvfvhgdsdsdsfv tdpddsdsdsuxhpb1dshgschpb1fvfvhgdsdsds
  7 >92    tpdcktdhphgsldtrsappob2w1cicztdpdck    tdpdcktdhphgsldtrsappob2w1cicztdpdck
  8        ufb1dshgds  			         uxhpb1dshg

Download the schedules here http://www.iberonesia.net/sdk_are.zip


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In summary for the day 07 (Figure 2) we get around 80 direct sun observations for extended brewers and 90 for short ones, 60 of this measurements will be in less than one minute from both brewer types. With three Sun Scan and Standard Lamp Measures per day. Lest frequent are the zenith sky measurements around 25 (~14 below 80º), uv scans around 15, and focused sun and global ozone (gi) with around 10. You can see also fv ‘field of view routines’ useful to check the sitting without going up to the terrace and the “ck” routine who send the data to Iberonesia database. {| border=“1” cellspacing=“0” cellpadding=“5”

On the schedule we use the burning time of the mercury and standard lamp to perform measurements we believe this not affect the measurements almost in MK.-IV (P Kiedron NOAA-EPA,http://esrl.noaa.gov/gmd/grad/neubrew/docs/CountsAndNoise.pdf ) please check if your version of brewer software allow this.

Table 7 Schedule for short range brewers TIME SZA AIRM SCHEDULE (single)

4:35  AM 107.3512  -3.3531 pdcktdhphgsldtrsappob2w1cicztdpdck    
5:55  AM 92.07111  -7.6703 tdpdzszszszsufb1fzfzhgzs              
6:32  AM 84.60847  10.6427 tdpdzsgifzb1ufhgzsgifzzsgigib1ufhgck  
7:25  AM 74.14947  3.66128 tdpddsdsdsufb1dshgdsb2zssldsdsgidsfv  
8:26  AM 62.17313  2.14224 tdpddsdsdsufb1dshgdsscb1fvfvhgdsdsdsfv
9:28  AM 50.56773  1.57439 tdpddsdsdsufb1dshgdsscb1fvfvhgdsdsdsfv
10:30 AM  40.3226  1.31162 tdpddsdsdsufb1dshgdsdszsdsgidsdszsds  
11:32 AM 32.94322   1.1916 tdpddsdsdsufb1dshgdsdszsdsgidsdszsds  
12:34 PM 30.69116  1.16288 ufb1dshgds                            
12:50 PM 31.14145  1.16837 tdpddsdsdsufb1dshgdsb2zssldsdsgidsfv  
1:51  PM 36.32369  1.24118 tdpddsdsdsufb1dshgdsdszsdsgidsdszsds  
2:53  PM 45.45691  1.42563 tdpddsdsdsufb1dshgdsdszsdsgidsdszsds  
3:55  PM 56.55404  1.81439 tdpddsdsdsufb1dshgdsscb1fvfvhgdsdsdsfv
4:57  PM 68.54131  2.73351 tdpddsdsdsufb1dshgdsdszsdsgidsdszsds  
5:59  PM 80.82179  6.26937 tdpdzszszszsufb1fzfzhgzs              
6:36  PM 87.99806  28.6259 tdpdzszszszsufb1fzfzhgzs              
7:13  PM 95.56144 -10.3185 pdcktdhphgsldtrsappob2w1cicztdpdck   

Table 8 : Schedule for extended range brewers TIME SZA AIRM SCHEDULE (extended) 4:36 AM 107.3552 -3.35239 pdcktdhphgsldtrsappob2w1cicztdpdck 5:56 AM 92.03624 -28.1439 tdpdzszszszsuxhpb1fzfzhgck 6:33 AM 84.5669 10.5615 tdpdzsgifzzsgifzzsgifzuxhpb1fzfzhgck 7:26 AM 74.10719 3.65179 tdpddsdsdsuxhpb1dshgb2zssldsdsgidsfv 8:27 AM 62.14861 2.1405 tdpddsdsdsuxhpb1dshgschpb1fvfvhgdsdsds 9:29 AM 50.58774 1.57506 tdpddsdsdsuxhpb1dshgschpb1fvfvhgdsdsds 10:31 AM 40.4273 1.31366 tdpddsdsdsuxhpb1dshgdszsdsgidsdszsds 11:33 AM 33.18441 1.19487 tdpddsdsdsuxhpb1dshgdszsdsgidsdszsds 12:35 PM 31.08483 1.16767 uxhpb1dshg 12:51 PM 31.56573 1.17365 tdpddsdsdsuxhpb1dshgb2zssldsdsgidsfv 1:52 PM 36.81258 1.24906 tdpddsdsdsuxhpb1dshgdszsdsgidsdszsds 2:54 PM 45.95709 1.43844 tdpddsdsdsuxhpb1dshgdszsdsgidsdszsds 3:56 PM 57.04984 1.83854 tdpddsdsdsuxhpb1dshgschpb1fvfvhgdsdsds 4:58 PM 69.03193 2.79449 tdpddsdsdsuxhpb1dshgb2zssldsdsgidsfv 5:59 PM 81.10977 6.47074 tdpdzszszszsuxhpb1fzfzhgck 6:36 PM 88.26949 33.1142 tdpdzszszszsuxhpb1fzfzhgck 7:13 PM 95.85958 -9.7952 pdcktdhphgsldtrsappob2w1cicztdpdck

Roughly every group of measurements takes one hour and start at half hours before noon and full hours after noon. Easily we can restrict the access to the terrace during the first 45 minutes of the start of every group of measurements to avoid interferences with the measurements. We are too many people on the campaign, around 40!! We must have to be strict about that. Of course this schedule is only a recommendation, during the maintenance days (5-7 of September) when access to the terrace is allowed.

I’m only test the schedule on MK-III and MK-II at Izaña if anybody wants to test the schedules I’m only need the latitude and longitude of the station to produce the schedules for you.

Data handling

The configuration files ICF and O3files will be collected by the intercomparison referee and deposited in the RBCC-E database during the setup days

The Bfiiles were sent to RBCC-E database (www.iberonesia.net) in near real-time (if we can solve the problem with the firewall ;))

Rene Stubi will act as independent referee with the technical assistance of Carmen Guirado.

Interchange File Format

As there are also different types of instrument every Principal Investigator must send the data in ascii format, the reported observations are than you think are “valid” with all the corrections which you think are necessary.

Format of the file The format of the file is the EXT-CSV format from WOUDCftp://ftp.tor.ec.gc.ca/documentation/www/extCSV.html, ftp://woudc:woudc*@ftp.tor.ec.gc.ca/documentation/www/o3_guide.pdf) for individual “OBSERVATIONS” with some limitations

*There is only one file per day the name of the file is:

Filename: O3DDDYY.XXX
 DDD is de day of the year
 YY   :is the two digits year
 XXX: Is the instrument identification (see PI/instrument table) 

* The time is reported in GMT * ObsCode, use the Numeric code not the character one, for example use “0” for direct sun observations not “DS” * The field of SO2 are omitted , the observation table are: Time, WLCode,ObsCode,Airmass,ColumnO3,StdDevO3

The following field names definitions are taken from WOUDC and repeated here as remember.

Field Definition Time hh:mm:ss WLCode Code to designate the wavelength pair(s) used for total ozone measurement.

      Code 0-7 are used for Dobson instruments only, 8 for Filter instruments 
      only and 9 for Brewer instruments only.)

ObsCode Code to designate the type of total ozone measurement. Airmass Relative slant path through atmosphere. ColumnO3 Discrete total column ozone (O3) amount (in Dobson Units, i.e., milli atm-cm)

                            	measured at the time of observation.

StdDevO3 Standard Deviation of total column ozone measurement (where applicable)

WLCode Description

0 AD wavelengths, ordinary setting
1 BD wavelengths, ordinary setting
2 CD wavelengths, ordinary setting
3 CC' wavelengths, ordinary setting
4 AD wavelengths, focused image
5 BD wavelengths, focused image
6 CD wavelengths, focused image
7 CC' wavelengths, focused image
8 Used to denote filter ozonemeter instruments
9 Used to denote Brewer spectrophotometer instruments
10-N To be defined

ObsCode Description

0 for DS Direct Sun
1 for FM Focused Moon
2 for ZB Zenith Blue Sky
3 for ZS Zenith Cloud (uniform stratified layer of small opacity)
4 for ZS Zenith Cloud (uniform or moderately variable layer of medium opacity)
5 for ZS Zenith Cloud (uniform or moderately variable layer of large opacity)
6 for ZS Zenith Cloud (highly variable layer with or without precipitation)
7 for ZS Zenith Cloud (fog)
8 for UV Ozone derived from UV spectrum
9 for  GI Total ozone value calculated from global irradiance (GI) type of measurement
 (specifically for Brewer instruments)

Example #CONTENT Class,Category,Level,Form WOUDC,TotalOzoneObs,1.0,1 #DATA_GENERATION Date,Agency,Version,ScientificAuthority 2007-09-03,IZO,1.00,Alberto Redondas #PLATFORM Type,ID,Name,Country,GAW_ID STN,300,RBCC-E,SP,60000 #INSTRUMENT Name,Model,Number Brewer,MKIII,185 #LOCATION Latitude,Longitude,Height 37.1, 6.73, 25 #TIMESTAMP UTCOffset,Date,Time +00:00:00,2007-09-03,00:00:00 #OBSERVATIONS Time,WLCode,ObsCode,Airmass,ColumnO3,StdDevO3 07:36:02,9,0,3.301,290.1,1.1, 07:50:21,9,0,2.846,289.3,1.9, 07:53:40,9,0,2.758,289.7,1.2, 08:08:01,9,0,2.434,289.7,0.9, 08:12:07,9,0,2.356,288.4,1.8, 08:16:13,9,0,2.283,290.4,0.3, 08:19:30,9,0,2.227,290.4,1.2,

= Ultraviolet = (by Julian Grobner)

Start and end times as close as possible to 85 SZA.

Measurements every 30 minutes, from 290 to 400 nm (or as far as possible), every 0.5 nm. The first wavelength should be sampled exactly at the half and full hour; each following wavelength measurement should be spaced by 3 seconds from the previous one.

The format of the UV files should be the following: *One Spectrum per file

Filename = dddhhmmG.xxx,

  • *ddd is the day of the year, hh and mm are the hours and minutes of the start of the measurement in UTC, xxx** a unique instrument identifier.

*First column, wavelength in nanometers (nm). *Second column, global Irradiance in W/m^2/nm *Third column, measurement time of each wavelength sampling in hours.decimal UT *The number of header lines is free, however there should not be any empty lines.

Since we are measuring global irradiance, I think that you should apply all corrections which you think are necessary to your data. That includes angular response corrections if your entrance optic does deviate noticeably from a cosine weighted response.

The processed UV data should be given to me in the required format at the latest by the day following the measurements. At the end of the campaign, all measured UV data should anyway be given to me for the final analysis.

instructions_to_the_participants_2008.txt · Last modified: 2015/02/27 10:03 by 0.0.0.0