Answer: Thermal inversion
Explanation: Thermal inversion or change the position of the air layer, when the warmer layer of air is above the cold layer, which is usually not the case. It happens due to a change in the normal temperature gradient, i.e. when the gradient becomes inverted. Such thermal inversions can occur in oceanic areas with a lot of upwelling near the coasts. Thermal inversion also occurs when sun radiation is less than radiation from the earth, which is the case during the night. The significance of these inversions is great, especially for air quality in polluted environments such as urban. The strongest inversions are during the winter and can then be dangerous due to poor air quality, which is measured by the AQI (Air Quality Index). The higher the AQI index, the greater the risk of bad air, that is, the worse air.
Asia is located north of the equator. East is the direction that Asia is located from the Prime Meridian. Asia is located in both the northern and eastern hemispheres.
You're right that volcanoes are out. We can find each of the abovementioned landforms in the USA, but about 50% of them are plains. They're specific for central USA and southern coast.
Answer: 2
