Sun Safety Alliance

As William Holstien of the New York Times claims, "Ultraviolet Rays are just around the corner!" Now is a good time to brush up on all things "UV".

UV, or ultraviolet, rays are the sun's "invisible" burning rays. They can cause sunburns, and in some cases skin cancer.

There are three types of UV rays:

UVA: Are more constant year-round and penetrate deeper into the skin's layers; UVA rays are also harmful and contribute to burning, premature aging of the skin, and the development of certain forms of skin cancer.

UVB: Are the primary cause of sun burning, premature aging of the skin and the development of skin cancer.

UVC: Are blocked by the ozone layer and do not reach the earth's surface.

From Sun Safety Alliance Photos

The more intense the sun, the greater your exposure to UV rays. The amount of UV that will reach you depends on the following:

Time of Day—UV is greatest when the sun is at its highest in the sky (between 10 am and 4 pm) and less in the early morning and late afternoon.

Season—While UV exposure is the greatest in the summer (May—August) in the United States, it is important to remember that UV rays reach Earth every day and you should be sun safe year-round—including wintertime! Snow can reflect 85% to 90% of the sun's UV rays!

Altitude—The air is cleaner and thinner at higher altitudes, so UV exposure is greater in the mountains than in the valleys. (For example, you can still get sunburned while skiing in the winter!)

Location—UV is strongest at the equator and gets weaker as you move towards the poles. Going tropical? Be prepared and take your sunscreen with you on family vacations.

Exposure Time—The longer you are out in the sun, the more UV rays you receive. Remember, you are exposed whenever you're out: picnics, Saturday yard chores, long drives, spectator/sports events, and more!

From Sun Safety Alliance Photos

What is the UV Index?!?!?

The UV Index (short for "Ultraviolet Ray Index") is a next-day forecast of the amount of skin-damaging UV radiation that's expected to reach Earth's surface when the sun is highest in the sky (solar noon). It was created to help people make informed decisions about the amount of time that they spend in the sun.

From Sun Safety Alliance Photos

How Should You Use This Index?
The UV Index is issued daily to advise you on the strength of the sun's UV rays in your region. Make a habit of checking the index so you'll know how much sun protection you'll need each day.

How Accurate Is the Index?
The UV Index is based on monitoring the sun's position, cloud movements, altitude, ozone data, and other factors. Each year the National Weather Service performs a validation of the UV Index forecasts by incorporating the help from several government agencies and private companies, hospitals, and colleges, that provide observations of surface UV radiation. From these observations, statistical corrections are made to ensure accuracy of the index.

Ozone & Local Effects
While it is well known that the Earth's ozone decreases the amount of UV rays you receive, the exact impact of ozone depletion is not yet fully understood. However, some local factors such as smog, or the type of reflective surface you're near, can also determine the amount of exposure you receive. For example, water, sand, snow, and concrete can all reflect ultraviolet rays, increasing your exposure.

Check the UV index of your hometown here!