Spring UV Is Sneaky: Why March Sunburns Catch You Off Guard
Cool air paired with strong rays is the seasonal mismatch that burns people in March.
Visible light is ~45% of sunlight; UV is ~5-7%; infrared makes up the rest.
The Skin Cancer Foundation notes UVA passes through clouds and ordinary window glass.
Frequently asked questions
How does sunscreen actually work?
Sunscreens use UV filters in two groups. Organic ('chemical') filters such as avobenzone absorb UV and release it as a small amount of heat. Mineral ('physical') filters — zinc oxide and titanium dioxide — mainly absorb UV and also scatter some. Both cut how much UV reaches living skin cells.
What does the UV index mean and when should I protect my skin?
The UV Index, from the EPA and WHO, rates the strength of midday UV on a scale from 1–2 (low) to 11+ (extreme). Dermatologists generally advise sun protection whenever it reaches 3 or higher. It appears in most weather apps and rises with sun elevation, altitude and proximity to the equator.
Is visible light bad for skin?
Visible light makes up about 45% of sunlight. Research shows high-energy visible (blue) light can worsen pigmentation and melasma, especially in medium-to-deep skin tones. Tinted sunscreens containing iron oxides help shield against it, which clear sunscreens generally do not.
r/30PlusSkinCare: 'Is the UV index app on my phone actually accurate?'
Sources & citations
- D'Orazio J et al., 'UV Radiation and the Skin,' Int J Mol Sci, 2013;14(6):12222-12248
- wearshade.com ↗