Information on Vitamin D Synthesis / Erythemal UV

Japanese

Exposure Time for Vitamin D Synthesis / MED (Climatology):Hateruma

Exposure Time around Noon (min.)
January February March
early middle late early middle late early middle late
MED505050403532323030
600 cm220201515121111109
1200 cm210108866655

April May June
early middle late early middle late early middle late
MED252525232120202018
600 cm2999877776
1200 cm2444444443

July August September
early middle late early middle late early middle late
MED181820202020202020
600 cm2666666667
1200 cm2333333334 4

October November December
early middle late early middle late early middle late
MED222530334045505050
600 cm27910121315202020
1200 cm245567810910

The numerical values in the row of 'MED', '600 cm2' and '1200 cm2' show the mean time to reach MED (Minimal Erythema Dose), the time required for 10 µg Vitamin D to be produced for a skin area of 600 cm2, and 1200 cm2 exposed to solar radiation in minutes, respectively.
By clicking each 10 day period, you can also see a diurnal variation of exposure time for that period.

Appropriate exposure time at every site shown below can be seen.
Cape Ochi-ishi (Hokkaido), Rikubetsu (Hokkaido), Sapporo (Hokkaido), Aomori (Aomori), Sendai (Miyagi), Tsukuba (Ibaraki), Yokohama (Kanagawa), Nagoya (Aichi), Otsu (Shiga), Osaka (Osaka), Miyazaki (Miyazaki), Cape Hedo (Okinawa), Hateruma (Okinawa).

Position of Hateruma