Some info on the data file
The data file contains the cloud-free and cloud-modified UV index for
an area covering The Netherlands
or the Benelux (as of 16 February 2026)
for each quarter of an hour from 03:00 UTC
up to and including 21:45 UTC, both in the usual non-dimensional unit,
and given with 3 decimals.
For time steps with insufficient sunlight to determine UV index or cloud
data or with missing cloud data, the entries have fill-values (-1.0).
The area that is covered by the data is:
>
Netherlands: 3.00 – 7.75°E, 50.25 – 54.00°N
>
Benelux: 2.25 – 7.75°E, 49.25 – 54.00°N
The original resolution of the data is the same as the standard UV grid:
0.25 by 0.25°. The line plots shown above are extracted from these data.
A version at higher resolution is made by interpolating the cloud-free data
to 0.05 by 0.05° and then averaging the cloud data over 0.15 by
0.15° around the grid cell center.
This "hr" version is available as of 11 February 2025 (back-processing of
the archive is not feasible).
The difference in grid cell average surface elevation between the two
resolutions is accounted for in the "hr" data for the Benelux region.
The example maps on the right show the area of The Netherlands
at (top)
the original resolution of 0.25 by 0.25°, and
(bottom)
the higher resolution of 0.05 by 0.05°.
- Most important global attributes:
-
-
data_product_date
- date of the data in the file
-
date_created
- date the data file was created
-
latest_cloud_modified_time
- UTC time of the last time slice filled with cloud-modified
UV index data
-
data_product_status
- "near-real time" for the operational processing
(as of 5 Dec. 2024) or "archive" for reprocessing data
- Main data variables:
-
uvi_clear
- Erythemal UV index cloud-free
-
uvi_cloudy
- Erythemal UV index cloud-modified
-
status
- Status of cloud-modified data:
0 = not available
1 = available for at least one grid cell
2 = forecast cloud data used (reserved flag)
- plus grid cell coordinate & time data.
-
Data file(s) can be downloaded from the links provide above under the
graph with the date in the filename. Today's data is also available with a
static filename via:
- >
https://www.temis.nl/uvradiation/UVI/uviec_bx.nc
- == 0.25 degree
- >
https://www.temis.nl/uvradiation/UVI/uviec_bx_hr.nc
- == 0.05 degree
|
Example plots of the cloud-free and cloud-modified UV index at 12:00 UTC
for 21 June 2024 over The Netherlands at a resoltion of 0.25 by 0.25°
(above) and 0.05 by 0.05° (below)
|
last modified: 06 March 2026
