Bioclimatology is the study of the effects of the climate on living things. Weather and atmospheric conditions can affect humans in many ways, both positive and negative. Our climate affects our moods, the chemical content of our bodies, the chances of getting a disease, and more. In Europe, awareness of the importance of bioclimatology has resulted in weather forecasts that include warnings of possible health hazards. The United States has not kept up with this pace, but meteorologists in America do often warn of such hazards as air pollution and allergen levels, as well as temperature extremes that might be dangerous because of frostbite or heat stroke.