Dr. Seth Stephens-Davidowitz analyzed tens of millions of Google searches for health related depression over nine years. His research focused on searches that would reflect the prevalence of actual depression or suggestions of emotional dips. What he discovered was another predictor for the impact of weather on mood and the effect of temperature related to medical depression. His research contends that although factors such as unemployment and season affected prevalence of depression or S.A.D. enhance depression, the strongest predictor by far was an area’s average temperature in January and February. Colder locations have higher rates of depression as related to the colder months. Temperature outweighed all other factors for depression.