UV station data based on operational TEMIS satellite ozone data	UV archive overview
UV index main page  |  UV dose main page

Time series of UV data

Time series UV index and UV dose data derived from the operational TEMIS assimilates ozone data -- so-called overpass files -- are generated from the UV data archive for selected places.

For all stations the overpass file contains the cloud-free UV index and UV dose data (starting 1 July 2002). For stations inside the MSG data area, see the 4th column, there is in principle also cloud-modified UV dose data in the overpass file (MSG data is available since 24 Jan. 2004).

Information on the structure of the data files is given below the table.
Information on availability of cloud-modified UV dose data is given on this page.

Data description

The header of an overpass file details contents and structure of the file:

# TEMIS v2.0 UV index and UV dose overpass file
# =============================================
# http://www.temis.nl/uvradiation/UVarchive.html
#
# Station name     = Zugspitze
# Station country  = Germany
# Station lon, lat = 10.98, 47.42
#
# Grid cell size              = 0.25 x 0.25 degrees
# Grid cell centre lon, lat   = 10.875, 47.375
# Grid cell average elevation = 1390 (+/- 424) m
# Grid cell within MSG area   = yes
#
# Data columns:
#      1 = YYYYMMDD        : date string
#   2, 3 = UVIEF, UVIEFerr : cloud-free erythemal UV index      [-]
#   4, 5 = UVDEF, UVDEFerr : cloud-free     erythemal  UV dose  [kJ/m2]
#   6, 7 = UVDEC, UVDECerr : cloud-modified erythemal  UV dose  [kJ/m2]
#   8, 9 = UVDVF, UVDVFerr : cloud-free     vitamin-D  UV dose  [kJ/m2]
#  10,11 = UVDVC, UVDVCerr : cloud-modified vitamin-D  UV dose  [kJ/m2]
#  12,13 = UVDDF, UVDDFerr : cloud-free     dna-damage UV dose  [kJ/m2]
#  14,15 = UVDDC, UVDDCerr : cloud-modified dna-damage UV dose  [kJ/m2]
#     16 = CMF             : average cloud modification factor  [-]
#     17 = ozone           : local solar noon ozone column      [DU]
#
# No-data entry = -1.000
#
#
# YYYYMMDD    UVIEF UVIEFerr  UVDEF UVDEFerr  UVDEC UVDECerr  ...   CMF    ozone
  20020701    8.752   0.526   5.180   0.354  -1.000  -1.000   ...  -1.000  313.2
  20020702    8.009   0.520   4.760   0.351  -1.000  -1.000   ...  -1.000  334.0
...

In case the station lies outside the MSG data area, the columns
with cloud-modified UV dose data have -1.000 throughout.   *)

The UV data is corrected for the effect of surface albedo on the surface UV radiation,
with the surface albedo is derived from a climatology; for details, see this page.

 
*) Note: The yes/no flag in the "MSG area" column of the table and comment line in the file header is based on the area covered by an MSG satellite in the default location (lon,lat)=(0,0). On days when a backup MSG satellite, located to the east or west, is used, stations just inside/outside the MSG perimeter may temporarily miss/have cloud-modified UV dose data.

last modified: 13 March 2023
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