The irregular imaginary line of thermal equilibrium between hemispheres, situated about 5 degrees North of the geographical equator and its positions changes with the seasons, moving slightly North in northern summer.

• A. Meteorological Equator
• B. Polar Front
• C. Monsoon
• D. Precipitation

Answer: (A)

The idea being tested is the meteorological equator, an imaginary belt that marks where the mean temperatures of the northern and southern hemispheres balance. This line sits about 5 degrees north of the geographic equator and isn’t fixed; it shifts with the seasons as heating and atmospheric circulation change.

Because the northern hemisphere receives more intense heating during its summer, the belt of warmer air shifts a bit northward, moving the meteorological equator in that direction. In contrast, during the southern hemisphere’s summer or when the NH cools, the line would move back toward the south. This seasonal migration reflects how differential heating between hemispheres drives shifts in atmospheric temperature balance.

Other terms don’t describe this temperature-balancing line. The polar front lies in higher latitudes where cold polar air meets warmer tropical air. A monsoon refers to seasonal reversal of winds and related rainfall, not a single temperature boundary. Precipitation is a weather event, not a defined boundary.