When we talk about climate change and skin, it is tempting to make a very simple connection:
Hotter planet = stronger sun = more UV damage.
But that isn’t quite how it works.
Heat and ultraviolet radiation are not the same thing. A scorching hot day does not necessarily have more UV than a cooler one — and you can receive a surprisingly high UV dose on a cool, cloudy day.
So does climate change have anything to do with UV exposure and skin health?
Yes. But the relationship is much more interesting than temperature alone.
First: UV is not heat
You cannot feel ultraviolet radiation.
That warmth you feel on your skin comes predominantly from infrared radiation and the surrounding air temperature. UV radiation is a different part of the electromagnetic spectrum altogether.
This matters because our behaviour is often guided by temperature.
A cool breeze can make us think the sun is harmless. A cloudy day can make us leave the hat at home. Yet significant UV can still reach the skin.
The World Health Organization recommends sun protection when the UV Index reaches 3 or above — regardless of whether the day actually feels hot.
So what controls how much UV reaches us?
Think of sunlight travelling through an atmospheric obstacle course before it reaches your skin.
Its UV component is influenced by:
- the angle of the sun
- latitude
- altitude
- cloud cover
- atmospheric ozone
- particles and aerosols in the atmosphere
- reflection from surfaces such as water, sand and snow.
That means climate can change UV exposure indirectly by changing some of the conditions the sunlight travels through.
Clouds are particularly interesting. Heavy cloud can reduce UV, but broken or scattered cloud does not necessarily mean low UV — and under some conditions UV exposure can remain substantial.
Ozone is also important because it absorbs part of the Sun's UV radiation before it reaches us. Less atmospheric ozone means more UV reaching Earth's surface.
And this is where climate change enters the story
Climate change and ozone depletion are not the same environmental problem.
The famous “ozone hole” was largely caused by ozone-depleting chemicals such as chlorofluorocarbons, rather than by greenhouse warming itself.
But the atmosphere is one enormous interconnected chemical and physical system.
Changes in temperature, atmospheric circulation, cloud formation, ozone chemistry and aerosols can all influence the amount and distribution of UV radiation reaching the surface.
WHO therefore notes that climate change — including its effects on ozone and cloud cover — is expected to influence surface UV radiation.
It isn't as simple as saying:
“Climate change means UV everywhere will increase.”
Some locations or seasons may experience increases, others decreases, and the pattern is influenced by regional atmospheric conditions.
Then there is another factor: us
This might ultimately be one of the biggest connections between climate and UV exposure.
Climate change alters the weather conditions in which people live, work and recreate.
Longer warm seasons, hotter summers and changing patterns of outdoor activity can change the amount of sunlight people receive over a lifetime.
For outdoor workers, gardeners, surfers, walkers, swimmers and anyone living the Australian outdoor life, actual UV dose is a combination of the UV environment and human behaviour.
And skin remembers cumulative exposure.
What does UV actually do to skin?
UV radiation is not just about sunburn.
UVA penetrates relatively deeply into skin, reaching connective tissue where repeated exposure contributes to photoageing and loss of elasticity.
UVB acts predominantly in the epidermis and is particularly important in sunburn and direct DNA damage.
Both are relevant to long-term skin health, and excessive solar UV exposure is the major environmental cause of skin cancer.
UV exposure can contribute to:
- DNA damage
- oxidative stress
- inflammation
- collagen and elastin damage
- changes in pigmentation
- reduced elasticity
- premature skin ageing and, most importantly,
- skin cancer.
So skincare cannot reasonably be separated from sun care.
And here's the bit I find fascinating
Our skin isn't sitting passively waiting for all of this to happen.
- It is constantly responding.
- Repairing DNA.
- Replacing cells.
- Managing inflammation.
- Producing antioxidants.
- Maintaining its extracellular matrix.
- Rebuilding its barrier.
Which takes us back to something we talk about often at PhycoHealth:
Skin health isn't simply about what you put on your skin. It is about the biological system you are asking to cope with the environment.
Good nutrition does not replace sunscreen.
Antioxidants do not make UV harmless.
And no skincare ingredient gives us permission to sit unprotected in the Australian midday sun.
But supporting healthy skin biology — from both inside and outside — makes sense precisely because our skin spends its entire life responding to environmental stress.
Climate change therefore changes the skincare conversation
Perhaps the interesting question isn't:
“Is climate change making UV stronger?”
It is:
“As our environment changes, how do we help our skin remain resilient within it?”
That means paying attention to the UV Index rather than simply the temperature.
It means hats, clothing, shade and appropriate sunscreen.
And it means remembering that skin health is bigger than the contents of the bathroom cabinet.
Your skin sits at the boundary between you and a changing planet.
Looking after that boundary is probably becoming more important, not less.