There are two ways, which the heat is transported in the biosphere. These are:
1. Winds/Air currents:
Tropics receive direct sun rays as compared to the temperate and polar zones of earth. Hence, the air near tropics tends to be hotter than the other two. In such situation hot air rises up in the atmosphere, whereas the colder air sinks to bottom. This results in air currents that bring about the circulatory movement of hot air from tropics and cold air from Polar Regions. Such movement decides the climate of a place.
2. Ocean currents:
Similar to the air, the oceans experience the cold and hot currents. Cold water from the Polar Regions becomes heavy and sinks to the bottom. This water then moves in parallel to ocean bed to reach the tropical zones. Here, it becomes hot and rises upward. This process is called upwelling. Hot water is then moved again to the cold regions with the help of winds.
Thus, the circulatory movement of ocean currents continues.