1996 UV Intercomparison Files

I.  Overview

	There are three levels of data: raw, formatted, and final.  The raw data is that obtained directly from the instruments.  This is converted into formatted data, which has a common file format for all the instruments and contains the measured signals.  Schedule files are used to supply additional information not found in the raw data, and a file of all the header information is generated along with the formatted files.  The formatted data is further analyzed to obtain the final data, which contains the values of interest.  Again, schedule files are used to specify which formatted files are to be used in the analysis, and a file of all the header information is generated.  

	The operation of the instruments is either discrete or continuous.  Scanning instruments are discrete, since at each time the signal from only one wavelength is measured.  Examples are the Brewer Spectrophotometers.  Instruments with filtered channels, such as the SERC Radiometer, are continuous since the signals from all the channels are measured during each time interval.  

	Each formatted file contains the signals from only one wavelength scan, for discrete instruments, or from one type of measurement for continuous instruments.  The type of the measurement is given by the signals detected, either dark, diffuse, or total.  The purpose of the measurement is either wavelength, responsivity, or irradiance.

II.  Channel Wavelengths

	The centroids of the filter transmittances of the channels of continuous instruments are used to determine the wavelengths of these channels.  
	
A.  SERC

	The raw files						Iwl1-wl2.FIL
		where wl1 = starting wavelength
		           wl2 = ending wavelength
	are combined into a single, formatted file		Tran696.UI
		where 696 is the month and year
			UI is the instrument
	The program						SERC_Filt_Cent_Calc.c
	is used to calculate the centroids,
	yielding						Cent696.UI
		where 696 is the month and year
			UI is the instrument
	The wavelengths of the channels are specified in	96WL01.SER
		where 96 is the year
			01 indexes the wavelength determination
			SER is the instrument

B.  USDA

	The raw files						uvmfriii.filter
		where iii = instrument (270 or 271)
	are condensed into a single, formatted file		Tran696.iii
		where 696 is the month and year
			iii = instrument (270 or 271)
	The program						USDA_Filt_Cent_Calc.c
	is used to calculate the centroids,
	yielding						Cent696.iii
		where 696 is the month and year
			iii = instrument (270 or 271)
	The wavelengths of the channels are specified in	96WL01.iii
		where 96 is the year
			01 indexes the wavelength determination
			iii = instrument (270 or 271)

III.  Emission Lines

	Lines from emission lamps and a HeCd laser are scanned to yield information about the bandwidth, wavelengths accuracy, slit-scatter function, and stray-light rejection of the instruments.  

A.  AES
	
	The raw files						SSddd.085
		where SS = source (CD, HG, ZN, HECD)
			ddd = day
	are combined with the information in the schedule
		file						96Ln_Sch.AES
	using the formatting program				Fmt_96AES_Ln.c
	to yield the formatted files				96dddFLn.AES
		where ddd = day
			FL indicates formatted line file
			n = index of scan (0 - 9, A - Z)
	The headers of the formatted files are stored in	96FL.AES

B.  EPA
	
	The raw files						LHddd96.101
		where ddd = day
	are combined with the information in the schedule
		file						96Ln_Sch.EPA
	using the formatting program				Fmt_96EPA_Ln.c
	to yield the formatted files				96dddFLn.EPA
		where ddd = day
			FL indicates formatted line file
			n = index of scan (0 - 9, A - Z)
	The headers of the formatted files are stored in	96FL.EPA
	 
C.  NSF
	
	The raw files						XV96hhmm.ddd
		where hh = hour	
			mm = minute
			ddd = day
	are converted from CSV to Tab using			CSVtoTab_File.c
	and are combined with the information in the schedule
		file						96Ln_Sch.NSF
	using the formatting program				Fmt_96NSF_Ln.c
	to yield the formatted files				96dddFLn.NSF
		where ddd = day
			FL indicates formatted line file
			n = index of scan (0 - 9, A - Z)
	The headers of the formatted files are stored in	96FL.NSF
	
D.  SERC
	
	The raw file						I960622B.CAL
	is combined with the information in the schedule
		file						96Ln_Sch.SER
	using the formatting program				Fmt_96SERC_Ln.c
	to yield the formatted files				96dddFLn.SER
		where ddd = day
			FL indicates formatted line file
			n = index of scan (0 - 9, A - Z)
	The headers of the formatted files are stored in	96FL.SER

E.  USDA
	
	The raw file						RSRHECD.DAT
	is combined with the information in the schedule
		file						96Ln_Sch.UDm
		where m = instrument (0 or 1)
	using the formatting program				Fmt_96USDA_Ln.c
	to yield the formatted files				96dddFLn.UDm
		where ddd = day
			FL indicates formatted line file
			n = index of scan (0 - 9, A - Z)
			m = instrument (0 or 1)
	The headers of the formatted files are stored in	96FL.UDm
		where m = instrument (0 or 1)

F.  Analysis

	The formatted files					96dddFLn.iii
		where ddd = day
			n = index
			iii = instrument (AES, EPA, etc.)
	are combined with information in the schedule
		files						96LnFile.iii
		where iii = instrument (AES, EPA, etc.)
	and the line wavelengths in the files			SSLn96.iii
		where SS = source (Cd, Hg, Zn,  He)
			iii = instrument
	using the analysis program				Calc_Cent.c
	to yield the centroids and bandwidths in the
		files						96Cent.iii
		where iii = instrument

IV.  Responsivity

	The responsivities of the instruments were determined by measuring the signals from calibrated irradiance lamps.  Where possible, the direct signal was calculated from the difference between the total signal and the diffuse signal.  The signal was divided by the lamp irradiance to obtain the responsivity.

A.  AES
	
	The raw files						XLddd96.085
		where ddd = day
	are combined with the information in the schedule
		files						96LpSchm.AES
		where m = type of scan (1 or 2)
	using the formatting programs				Fmt_96AES_Lpm.c
		where m = type of scan (1 or 2)
	to yield the formatted files				96dddFRn.AES
		where ddd = day
			FR indicates formatted responsivity file
			n = index of scan (0 - 9, A - Z)
	The headers of the formatted files are stored in	96FR.AES

B.  EPA
	
	The raw files						XLddd96.101
		where ddd = day
	are combined with the information in the schedule
		file						96Lp_Sch.EPA
	using the formatting program				Fmt_96EPA_Lp.c
	to yield the formatted files				96dddFRn.EPA
		where ddd = day
			FR indicates formatted responsivity file
			n = index of scan (0 - 9, A - Z)
	The headers of the formatted files are stored in	96FR.EPA

C.  NSF

	No files available

D.  SERC

	The raw files						I9606dda.CAL
		where dd = day of month
			a = index
	are combined with the information in the schedule
		file						96Lp_Sch.SER
	and the wavelength file				96WL01.SER
	using the formatting program				Fmt_96SERC_Lp.c
	to yield the formatted files				96dddFRn.SER
		where ddd = day
			FR indicates formatted responsivity file
			n = index of scan (0 - 9, A - Z)
	The headers of the formatted files are stored in	96FR.SER

E.  USDA

	The raw files						UVRSRddd.DAT
		where ddd = day
	are combined with the information in the schedule
		file						96Lp_Sch.UDm
		where m = instrument (0 or 1)
	and the wavelength file				96WL01.UDm
		where m = instrument (0 or 1)
	using the formatting program				Fmt_96USDA_Lp.c
	to yield the formatted files				96dddFRn.UDm
		where ddd = day
			FR indicates formatted responsivity file
			n = index of scan (0 - 9, A - Z)
			m = instrument (0 or 1)
	The headers of the formatted files are stored in	96FR.UDm
		where m = instrument (0 or 1)

F.  Analysis

	The formatted files					96dddFRn.iii
		where ddd = day
			n = index
			iii = instrument (AES, EPA, etc.)
	are combined with information in the file
		schedules					96R_Sch.iii
		where iii = instrument (AES, EPA, etc.)
	the lamp irradiances in the files			llllpmyy.irr
		where llll = lamp (E002, S702, 271, etc.)
			p = position (H or V)
			m = calibration month (1 - 12, A - C)
			yy = calibration year
	and the uncertainties in the files			96UHnPme.iii
		where n = lamp housing (1 or 2)
			m = power supply (1 or 2)
			e = environment (I or O for indoors and
			        outdoors)
			iii = instrument
	using the analysis program				Calc_Resp.c
	to yield the responsivities in the files			96dddRnn.iii
		where ddd = day
			R indicates responsivity file
			nn = index (1 - 99)
			iii = instrument
	The headers of the responsivity files are stored in 	96R.iii
		where iii = instrument

V.  Solar Irradiance

	The signals measured by the instruments were divided by the responsivities determined at the closest times to the scans to obtain the solar irradiance.

A.  AES
	
	The raw files						UZddd96.085
		where ddd = day
	are combined with the information in the schedule
		files						96S_Sch.AES
	using the formatting program				Fmt_96AES_S.c
	to yield the formatted files				96dddFnn.AES
		where ddd = day
			F indicates formatted irradiance file
			nn = index of scan (01 - 99)
	The headers of the formatted files are stored in	96FE.AES

B.  EPA
	
	The raw files						UAddd96.101
		where ddd = day
	are combined with the information in the schedule
		files						96S_Sch.EPA
	using the formatting program				Fmt_96EPA_S.c
	to yield the formatted files				96dddFnn.EPA
		where ddd = day
			F indicates formatted irradiance file
			nn = index of scan (01 - 99)
	The headers of the formatted files are stored in	96FE.EPA

C.  NSF

	No files available

D.  SERC

	The raw files						I9606dda.DAT
		where dd = day of month
			a = index
	are combined with the information in the schedule
		file						96S_Sch.SER
	and the wavelength file				96WL01.SER
	using the formatting program				Fmt_96SERC_S.c
	to yield the formatted files				96dddFnn.SER
		where ddd = day
			F indicates formatted irradiance file
			nn = index (01 - 99)
	The headers of the formatted files are stored in	96FE.SER

E.  USDA

	The raw files						96ddd.iii
		where ddd = day
			iii = instrument (270 or 271)
	are combined with the information in the schedule
		file						96S_Sch.UDm
		where m = instrument (0 or 1)
	and the wavelength file				96WL01.UDm
		where m = instrument (0 or 1)
	using the formatting program				Fmt_96USDA_S.c
	to yield the formatted files				96dddFnn.UDm
		where ddd = day
			F indicates formatted irradiance file
			nn = index of scan (01 - 99)
			m = instrument (0 or 1)
	The headers of the formatted files are stored in	96FE.UDm
		where m = instrument (0 or 1)
	
F.  Analysis

	The formatted files					96dddFnn.iii
		where ddd = day
			nn = index
			iii = instrument (AES, EPA, etc.)
	are combined with information in the file
		schedules					96E_Sch.iii
		where iii = instrument (AES, EPA, etc.)
	and the responsivity in the files			96dddRnn.iii
		where ddd = day
			nn = index
			iii = instrument
	using the analysis program				Calc_Irrad.c
	to yield the irradiance for discrete operation 
		in the files					96dddhht.iii
		where ddd = day
			hh = hour	
			t = tenths of hour
			iii = instrument
		and for continuous operation 
		in the files					96ddd.iii
		where ddd = day
			iii = instrument
		for continuous operation
	The headers of the irradiance files are stored in	96E.iii
		where iii = instrument

VI.  Miscellaneous

	Emission lines of lamps and laser are given in
		files						SS.txt
		where SS = source (Hg, Cd, Zn, HeCd)

	Irradiances of NIST lamps are given in 
		files						llllpmyy.irr
		where llll = lamp (E002, E004, etc.)
			p = position (H or V)
			m = calibration month (1 - 12, A - C)
			yy = calibration year

	Ancillary information in files	
		Location and geographical information	UV96Loc.txt
		Instrument information			UV96Inst.txt
		Source information				UV96Src.txt
		Lamp housing information			UV96HS.txt
		Lamp power supply information		UV96PS.txt