Õhumass

An õhumass, or air mass, is a large body of air that has similar temperature and humidity throughout. These large volumes of air are formed when air stays over a particular region, such as a large landmass or an ocean, for an extended period. This prolonged contact allows the air to acquire the thermal and moisture characteristics of the surface below.

Õhumassid are classified based on their latitude and the type of surface they originate from. Continental air masses form over land, tending to be drier, while maritime air masses form over oceans, usually being more humid. Latitudinal classifications include polar, tropical, and equatorial, indicating whether the air mass is cold, warm, or hot. Combining these, we can have, for example, a continental polar air mass, which is cold and dry, or a maritime tropical air mass, which is warm and humid.

The interaction of different õhumassid is a primary driver of weather. When two air masses with contrasting properties meet, they create a weather front. The boundary between these air masses is where significant weather changes often occur, such as precipitation, temperature shifts, and wind changes. The movement and eventual dissipation or merging of õhumassid dictate daily and seasonal weather patterns across the globe. Understanding õhumassid is fundamental to weather forecasting and climatology.