In weather lingo, think of an air mass as a gigantic bubble of air hanging out in the sky, keeping its chill vibes consistent in terms of temperature and humidity. This air party can cover massive distances, like hundreds or thousands of kilometers wide and reach as high as the top part of the troposphere, which is like 10–18 km above our heads. when the atmosphere spends quality time with a big land or sea area, it picks up on their temperature and moisture style. The cool part is, these major air mass personalities start their journey at either polar or subtropical spots. As they venture into the middle latitudes, it’s like this awesome mashup of polar and tropical air having a big mixing and mingling session.

Categorisation of Air Masses

Meteorologists classify anticyclone based on where they are formed. Here is the classification. Typically, there are 4 types of air masses:

• Arctic: These anticyclone form in the Arctic region and are very cold.
• Tropical: These anticyclone form in low lying latitudes and are warm up to a moderate level.
• Polar: These air masses form in the high-latitude region and are cold.
• Equatorial: They start forming over the Equator and are warm.

Besides this classification, there is another way to categorise air masses. Meteorologists classify them based on whether they form over water or land. These distinctions are:

• Maritime: Maritime ones form over the water bodies and are filled with moisture.
• Continental: Whereas, the Continental ones form over the land and are arid.

For instance, an air mass formed over interior Asia is a continental polar air mass that is cold and dry. However, one that is formed over the Indian Ocean is a tropical air mass that is humid and warm.

Air Mass Categorisation of the USA

Continental Polar: This air mass takes shape over expansive land areas, like the vast reaches of Northern Canada. It tends to be quite stable and lacks the usual cloud formations as it originates over land. When these masses interact with heat or moisture from the ground, they have the potential to bring about snow or rain.

Maritime Polar: Originating over large bodies of water, these air masses gather significant moisture. As they move toward land in the middle and high latitudes, they can lead to heavy rainfall, especially when pushed upward by mountain slopes or caught up in cyclonic activity.

Continental Tropical: Emerging in the lower latitudes, often from deserts or inland areas, these air masses typically form during the summer. Subject to intense heat and lacking ground moisture, they are commonly dry and arid in nature.

Maritime Tropical: Born over the expansive tropical oceans, these air masses are laden with moisture, making them prime contributors to rainfall. If they move towards higher latitudes, the cooling effect from the land surface can lead to fog. Over continental regions, they heat up significantly, fostering convectional rain or thunderstorms.

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