Final answer:
The four main air masses include Tropical, Polar, Maritime, and Continental. They can change due to movement over different surfaces and interactions with other air masses, affecting weather and climate. Atmospheric composition, particularly greenhouse gases, and seasonal sunlight variations also impact atmospheric circulation and long-term climate changes.
Step-by-step explanation:
The four main air masses discussed typically include Tropical (warm), Polar (cold), Maritime (moist), and Continental (dry). These air masses are named based on their source region's latitude (tropical or polar) and their moisture content (maritime or continental). The way these air masses are usually stacked is dependent on the general circulation of the atmosphere and boundaries that separate them, such as front lines.
The changes in air masses occur due to the movement over different surfaces, which can cause them to gain or lose heat and moisture, and interactions with other air masses. These interactions can lead to weather events such as storms when warm and cold air masses meet.
Atmospheric composition and changes therein, such as increases in greenhouse gases like CO₂, can influence air temperature and, consequently, weather and climate patterns. Furthermore, the seasonal variation in sunlight due to Earth's orbit and axial tilt drives atmospheric circulation and can lead to long-term climate changes.
The atmosphere is structured into the troposphere, stratosphere, mesosphere, and ionosphere. Most of Earth's weather occurs in the troposphere where clouds form. The most abundant component of the atmosphere is nitrogen (N₂), followed by oxygen (O₂). The presence of other trace gases like water vapor (H₂O), carbon dioxide (CO₂), and ozone (O₃) also play crucial roles in Earth's climate and weather patterns.