Relative humidity is the percentage or ratio of the amount of water vapor in a volume of air at a given temperature and the amount that it can hold at that given temperature. An amount of water vapor in warm air will result to a lower relative humidity than in cool air.ummary: 1.Humidity is the amount of water vapor in the atmosphere while relative humidity is one type of humidity. 2.Humidity is the water content of the mixture of water vapor and other elements found in the air while relative humidity is the percentage of water vapor in the air at a given temperature.
Actinic keratosis (AK) is a UV lightâinduced lesion of the skin that may progress to invasive squamous cell carcinoma. It is by far the most common lesion with malignant potential to arise on the skin. See the image below.
Keratosis refers to a group of skin disorders that are caused by abnormal growth of keratin, which is a key structural protein found in the skin, hair and nails.t is most commonly found on areas of the skin that are exposed to the sun, such as the face, back of the hands, forearms, scalp, or neck. Symptoms of actinic keratosis include: 1  A dry or rough patch of skin (usually less than one inch in diameter). 2  A flat to slightly raised patch of skin.