Climatology is the study of climate, its global variations and causes. Climatologists record mean daily, monthly, and annual temperatures and monthly and annual rainfall totals, as well as maximum and minimum values. Other data collected relate to pressure, humidity, sunshine, cold cover, and the frequency of days of frost, snow, hail, thunderstorms, and gales. The main facts are summarised in tables and climatological atlases published by nearly all the national meteorological services of the world. Research Climatology