Do the UV rays the sun emits go through clouds?

Question

I heard from a couple of people that even if the suns begins to be covered by clouds when you're tanning, the UV rays that darken your skin can still darken it. Is this true? Anyway other information regarding this subject would also be greatly appreciated =).

Answer 1

no, i don't think that uv rays can penetrate clouds unless they are especially high and thin.

Answer 2

No, the higher the wavelength of light, the more energetic they are but less able to penetrate particulate substances like clouds.  The wavelength of light determines the size of particles which are invisible to them, and the small water droplets that make up clouds are even too big for visible light to get through directly.

Answer 3

Yes!

Answer 4

Yes, UV rays do penetrate the clouds.  You can get sunburned on a cloudy day.

Too much sun is dangerous. Summertime is when the sun is highest in the sky and the rays are most direct. This means that there is less filtering by the earth's thin atmosphere. You must take precautions against the sun's ultra-violet (UV) radiation.

UV radiation is a normal component of the sun's energy that in large quantities causes sunburns, and may eventually lead to premature wrinkling, skin cancer, or cataracts. Simple measures reduce risk. Here are some basics:

If your shadow is shorter than you are tall, UV levels will be high.

UV radiation is most intense between 10am and 3pm. Limit your exposure to direct sun during these hours.

Don't lay in the sun. When out for extended periods, wear a hat, along with light-colored, lightweight clothes that cover your arms, legs and the rest of your skin. Use sunglasses with UV protection and apply a sunblock.

Children need extra protection since their bodies are still developing and too much sun can be much more dangerous than to adults.

Lighter skin is more affected by UV radiation but all skin types require some type of protection.

UV radiation penetrates clouds and water so even on a cloudy day or while swimming, take precautions.

Shiny, smooth, or bright surfaces such as cement or sand can reflect UV radiation.

Cooler temperatures do not lower UV values. Skiers commonly are sunburned when they underestimate the sun's UV radiation reflected by snow.

As the UV index gets higher, use a sunscreen with a higher SPF (Sun Protection Factor) and spend less time in the sun.

If you notice blotches or other permanent changes to your skin, see your doctor.

Answer 5

Yes.  You can get a tan on a cloudy day.

eelfins - ultraviolet is higher frequency, which means SHORTER wavelength.

.

Answer 6

It's absolutely true, more people get sunburned when it's cloudy than when it's sunny because people think that the UV rays are blocked by the clouds and don't wear sunscreen.

Answer 7

From personal experience I can answer with a definite and painful Y-E-S..! The worst sunburn I've ever had happened on a totally overcast day with no sun visible at all.

Answer 8

Yes they can.  You can get a sunburn on a hazy overcast day almost as easily as a bright sunny day.

I found this information from http://www.theweatherprediction.com/haby...

&

This from the department of energy (so it's at least 1/2 true!)

http://www.newton.dep.anl.gov/askasci/ge...

5. You may have heard this: "you can get a sunburn just as quickly on a cloudy day as compared to a sunny day". In many cases this is completely false. On an overcast day, especially an overcast rainy day, the amount of UV reaching the surface is significantly reduced. Any overcast conditions will reduce UV radiation reaching the surface. With this said, partly cloudy conditions do NOT reduce the sunburn risk much. Some people make the mistake of staying outside longer when there is cloud cover. This increased time can make up for the fact there is less UV radiation reaching the surface. This mistake is worst on a partly cloudy day.

>>  name       BILLY

> >>  status     other

> >>  age        50s

>

> >>  Question - iS IT POSSIBLE TO GET SUN TANNED/BURNED ON A CLOUDY OR

> >> RAINY DAY?

>

>Yes! It's definitely possible to get a sunburn on a cloudy day. Sunburns

>are caused by UV light, which is not blocked by clouds, just by sunscreen.

>Sunburns are sometimes worse on cloudy days than on sunny ones because

>people don't realize they're at risk for getting sunburned.

>---------

>Christine Ticknor

>Ph.D. Student

>Yale University

>New Haven, Connecticut

======================================...

>Yes. It has happened to me. It turns out that the ultraviolet rays from

>the sun actually penetrate clouds better than visible light does, so you are

>not getting as much shielding as your eyes might think that you are.

>

>In a similar vein, it is also possible to get a sunburn while sitting in the

>shade. Ultraviolet rays scatter more strongly in the atmosphere than

>visible light, so they can literally bounce off the air and then to you even

>if you are in the shade. If you can see blue sky, you are getting scattered

>UV.

>

>Richard E. Barrans Jr., Ph.D.

>Assistant Director

>PG Research Foundation, Darien, Illinois

======================================...

Answer 9

Yes actualy it can. I got sun burn on a cloudy day.

Answer 10

Yes, it's true.  You can get sun-burned or sun-tanned through the clouds.  Always wear sunscreen!  :-)  

Clouds block visible light, but visible light is only a small fraction of the electromagnetic spectrum.  Ultraviolet light has smaller wavelengths than visible light, so it passes through clouds.