Calculated Ultraviolet Exposure Levels for a Healthy Vitamin D Status and no sunburn

Version 1.2, Copyright © 2011 NILU, Ola Engelsen
Norwegian Institute for Air Research

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Solar Geometry for Irradiance Calculations

Month Day

Latitude (degs N) Longitude (degs E)

When checked, use degrees for Solar Zenith Angle directly and ignore Date, Time, and Location


Skin type: 1 2 3 4 5 6
Press here for description of skin types.

Timing of exposure: Around midday Start time (hours UTC)

Body exposure: %.

Desired dietary equivalent dose of vitamin D: IU. (1000 IU widely recommended every other day)


Cloudless sky: Visibility of km, Range [5-350] km. Ångström β of , Range [0.0-0.4] (AOD = βλµm-1.3).

Scattered clouds: Cloud fraction of %, Range [0-100]. Cloud liquid water column of g m-2, Range [0-5000].

Broken clouds (radiation enhancement): Cloud liquid water column of g m-2, Range [0-5000].

Overcast sky: Cloud liquid water path (LWP) of g m-2, Range [0-5000]. (Thin clouds: LWP < 50 g m-2; Thick clouds: LWP > 500 g m-2)

Estimate cloud thickness from UV index assuming overcast sky: UV index [0-20]


Total ozone column: Dobson Units (DU), Range [100-600]
Press here for total ozone column measurements from the satellite instruments (OMI).


Surface elevation km above sea level. Range [0.0-6.0] km

Surface albedo of Range [0.0-1.0].

Surface type:






This work has been funded by the European Commission (EC) and the Norwegian Research Council ( NFR) through the projects UV Radiation in the Arctic: Past, Present and Future (UVRAPPF), European Database for UV Climatology and Evaluation (EDUCE) and Integrated Assessment of Health Risks of Environmental Stressors in Europe (INTARESE).

Contact: nilu@nilu.no (Arve Kylling or Tove Svendby)
NILU - Norwegian Institute for Air Research
Instituttveien 18
NO-2027 Kjeller
Norway