It is the center of our solar system and it makes life happen here on Earth. The Sun has a lot of power in our lives. But with that power comes harmful radiation.
Ultraviolet rays are invisible radiation rays emitted from the Sun. There are UV-A, UV-B, and UV-C rays… but we simply refer to them all in the blanket term of “UV Rays”.
UV-C rays are completely absorbed by our ozone layer… so we’re protected from them. They’re the most harmful if they made their way to our atmosphere. Most of the UV-B rays are absorbed by the ozone layer but not all….some make it through… and most of the UV-A rays make it through to our atmosphere.
It’s the UV-A and UV-B rays that are the most harmful to our bodies. They cause premature aging and skin cancer. Most skin cancers are caused by over-exposure to these UV rays. They can also cause potentially blinding eye diseases
The UV rays are measured with a number called the UV Index. The higher the index, the stronger the rays. In the summer, the index is much higher than in the winter. When we have high index values, you can burn in less than 20 minutes. The lower UV rays – like what we have in the winter, it would take about an hour.
And speaking of protecting the skin, SPF 100 may be a waste of your time. Anything around SPF 30 is almost just as protective blocking out 97% of the harmful rays. Nothing will block out 100% of the dangerous rays. According to a Health Day poll, 80% of adults know they should be applying sunscreen every two hours but only around 30% typically do.
But just when you think it’s not safe to be outdoors at all… UV rays actually do have benefits. The Centers for Disease Control recommend around 5 to 15 minutes of sun exposure 2 to 3 times a week. That’s because UV rays in very small amounts can help the production of vitamin D. Another interesting tidbit about these invisible rays is that some insects, birds, and reptiles can actually see them bounce off of plants. Think of it kind of like a dog whistle.
The highest UV index in North Dakota in the summer are around 8. In January, we average zero.