Information on Vitamin D Synthesis / Erythemal UV


Exposure Time for Vitamin D Synthesis / Minimal Erythema Dose (MED):Climatology

Climatology, here, means the long-term averaged view of the various climatic parameters. In this climatology section, the exposure time for vitamin D synthesis and MED averaged over long term for each site and season is shown as climatic data. Even if you can not access the real-time data, you can know approximate UV exposure time based on climatic data.

In this climatology section, the climatic data are shown in each 10 day period. Though some sites have not accumulated enough data so far to derive climatic data of good quality because data acquisition for analysis of vitamin D synthesis started in 2013, we expect that these climatic data still provide an indication for approximate UV exposure time.

The exposure time for vitamin D synthesis and MED corresponding to UV radiation around noon can be seen in the table of every site. The exposure time for vitamin D Synthesis is shown as the time required for 10 µg vitamin D to be produced for a skin area of 600 cm2 and 1200 cm2 exposed to solar UV radiation. By clicking each 10 day period, you can also see a diurnal variation of exposure time for that period. Here, skin photo type (SPT) Ⅲ is supposed. For people who have other skin types than SPT Ⅲ, please see the Correction factor of the table "Skin Types".

Appropriate exposure time at every site shown below can be seen.
Cape Ochi-ishi (Hokkaido), Rikubetsu (Hokkaido), Tsukuba (Ibaraki), Cape Hedo (Okinawa), Hateruma (Okinawa).

Monitoring Stations