Some info on the data file
The data file contains the cloud-free and cloud-modified UV index for
an area covering The Netherlands for each quarter of an hour from 03:00 UTC
up to and including 21:45 UTC, both in the usual non-dimentional unit,
and given with 3 decimals.
For quarters with insufficient sunlight to determine the UV index or the cloud
data or with missing cloud data, the entries have fill-values (-1.0).
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 example maps on the right show the area that is covered by the data:
longitude = 3.00 – 7.75°E, latitude = 50.25 – 54.00°N,
at:
(top)
the original resolution, i.e. divided in 19 by 15 grid cells of 0.25 by 0.25°, and
(bottom)
the higher resolution, i.e. divided in 95 by 75 grid cells 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_nl.nc
- == 0.25 degree
- >
https://www.temis.nl/uvradiation/UVI/uviec_nl_hr.nc
- == 0.05 degree
|
Example plots of the cloud-free and cloud-modified UV index at 12:00 UTC
for 21 June 2024 at a resoltion of 0.25 by 0.25° (above)
and 0.05 by 0.05° (below)
|
last modified: 27 October 2025
