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        Preliminary Scientific Sponsorship Statement
    for the data from the UV-B monitoring network of the
                Japan Meteorological Agency.


This document describes the deployment of instruments and
the responsivity calibration procedures that are used in the
JMA network.  A more extensive sponsorship statement which
deals with other aspects of the data will be provided later.

The instruments in the network are Brewer MK-II
spectrophotometers located as shown in Table 1.

Table 1         JMA Network for UV monitoring.
[Station]                            [location]
[Instrument]   [purpose]
 Sapporo                 43:03N  141:20E     #058
Routine Observation [from 1991]
 Tsukuba                      36:03N  140:08E     #052
Routine Observation [from 1990]
 Tsukuba                      36:03N  140:08E     #113
Standard use
 Kagoshima               31:38N  130:36E     #059
Routine Observation [from 1991]
 Naha                         26:12N  127:42E     #060
Routine Observation [from 1991]
 Syowa (Antarctica)      69:00S     39:35E     #091
Routine Obs.[from 1991] (1991-94: #034)
Routine observations are made at every hour from sunrise to
sunset.

QC (calibration) system in the network.
The responsivity of each Brewer is obtained by measuring the
irradiance from NIST lamps supplied with 7.900 or 8.000A
constant current just before being sent to observation site
(we define it calibration).
We use two other kinds of lamp:-  internal lamp which is
installed already in spectrometer and the external one.  The
time change of the responsivity is corrected by comparison
between external and internal lamp(we call stability check).
There are 5 external lamps at each site which are checked
against themselves in the dark, once a week for two lamps,
once a month for three lamps, and once each half year for
five lamps.  Simultaneously the responsivity of each
spectrometer is also checked.  The internal lamp is used
three times a day, sunrise, noon and sunset times in order
to monitor the responsivity of each spectrometer.

An international intercomparison was carried out at Table
Mountain near Boulder (USA) in September 1994.  From Japan,
spectrometer #113 of Brewer was brought as a Japanese
standard, and according to the results we revised the
responsivity of all other Brewers used in UV-B network in
Japan.  These were based on the intercomparisons between
standard #113 and the others for routine observation use at
each station.

The latest international intercomparison of the standard
spectrometer between Japan and Canada was carried out during
the period February through March 1997 at AES in Toronto,
Canada.  Calibration activities are summarized in tables 2,3
and 4

Definition of terms:
Intercomparison.    The comparison between JMA's standard
instrument and the instruments in routine use
          and between the JMA standard and standard
     instruments of other agencies ( i.e. AES).
Calibration.   The source of calibration is a 1000W lamp
that is traceable to NIST.
Stability check.    Monitoring for the time change of
responsivity using lamps that are not calibrated.

.
Table 2  Types and frequency of calibration activities in
the JMA UV network.
          [Spectral interval] [Frequency.]        [Scans]
Intercomparison          0.25nm         every 3 years
see 3.(1)
Calibration         0.50nm         every 3 years       see
3.(2)
Stability checks:
External 50W lamp   0.50nm         2 lamps: every week 3
double scans
                         3 lamps: every month     3 double
                    scans
                         5 lamps: every half year 3 double
                    scans
Internal 20W lamp   variable       3 times a day       5
scans

note1: external lamps are checked simultaneously
note2: the responsivity of instrument for every month are
calculated by this stability check
note3: external lamp is not necessary to be traceable to
NIST lamp
note4: spectral interval for internal lamp depends on
wavelength being scanned
note5: The intercomparison and the calibration specifics do
not apply to the observation at Syowa.

Table 3 The most recent intercomparisons for of JMA
spectrometers
[Instrument]   [Frequency]    [Date of latest]
[Site]         [standard instrument]
#113 Standard  every 2 years  Feb. - Mar., 1997
Toronto        AES #013.
#058 Sapporo   every 3 years  Jul.,1997      Sapporo
#113
#052 Tsukuba   every  year    Jun.,1997      Tsukuba
#113
#034 Tsukuba   every  year    Jun.,1997      Tsukuba
#113
#059 Kagoshima every 3 years  Sept.-Oct.,1995
Kagoshima #113
#060 Naha every 3 years  Oct.,1996      Naha      #113
#091 Syowa(Antarc.)  Temporal Sept.-Oct.,1993
Tsukuba        #113

Table 4.  Details of calibration procedures
(1) Intercomparison for each are done by comparing with the
standard measuring solar radiation.
            sky condition     clear sky
            frequency         every 30 minutes from sunrise
to sunset (several days)
            range        290-325nm per 0.25nm
            error in timing   < 1.0 s
(2) Calibration by NIST lamp
           NIST lamp     DXW type 1000 W lamps (Eppley,inc.
and Optronic,inc.)
           distance      50.0 cm
           lamp housing  manufactured Takasho,inc., Japan
           power supply  manufactured Takasago,inc., Japan
           error of ampere    < 0.0005 A
           range         290-325nm per 0.5nm double-scans
           scans         15 times      (It takes about 3
hours to complete a lamp test)
(3) Check of responsivity by external lamp after (1) and (2)
          lamp and holder     5 halogen 50 W lamps (SCI-
TEC,inc.)
          distance       5 cm
          power supply and lamp housing          : SCI-
TEC,inc.
          Range          290-325nm per 0.5nm double-scan
          scans          3 times    (It takes about 40
minutes to complete a lamp test)


Masaatsu  Miyauchi
97/09/15:    for the
Japan Meteorological Agency