I can't say that it is a long term effect of the sun because I don't know you well enough to determine that. Spending alot of time in the sun does have a long term effect, wrinkling being one of them. However, as women get older and hormones begin to change, this effects the skin as well. Skin on the shins, particularly, appear thin and scaly. Some of it is external, but some of it comes from internal reasons. Continue applying rich emollient lotions or creams. Always use sunscreen #30 or higher, when out in the sun, even for casual reasons. Add some oil to your diet such as flax seed oil (you can purchase it at the healthfood store) and spray it on your salad or foodor just use vegetable oil.
If you feel that your condition persists or worsens then you can make an appointment with a dermatologist for evaluation.
The skin is constantly exfoliating itself, dead cells die off and new cels replace them. You can use a loufah sponge in the shower if you want to exfoliate your skin. Your skin still needs to me moisturized. As I mentioned earlier, apply emollient creams and moisturizers. Please try adding healthy oils to your diet, as well, to promote supple moist skin. Without examining your skin, it is difficult to know exactly what it looks like, you would have to see a dermatologist for further investigation. I can only suggest what you might do to get moisture back into your skin, as to reduce the dry scaly appearance.
I wish you well!