Latitudinal heat balance
Also called: Net radiation balance · Topic: Solar Radiation, Heat Balance and Temperature · NCERT: Class 11, Ch 8 "Solar Radiation, Heat Balance and Temperature"
Meaning
Latitudinal heat balance is the gap, at each latitude, between the radiation the Earth-atmosphere system takes in and the radiation it sends back out. Between about 40°N and 40°S, more energy comes in than goes out, so this belt has a surplus. Closer to the poles, more energy goes out than comes in, so those areas have a deficit. Winds carry the extra heat towards the poles through the Hadley, Ferrel and polar cells (large loops of rising and sinking air) and through cyclones. Ocean currents carry it too. Because of this, the tropics do not keep heating up and the poles do not freeze for good.
Example
The Gulf Stream and the North Atlantic Drift are warm ocean currents. They carry tropical heat north-east across the Atlantic Ocean. This keeps the coast of Norway, far north in Europe, free of ice in winter.
Don't confuse with
- Heat budget of the Earth: it is the balance for the whole planet together. About 65 of every 100 units of incoming sunlight are absorbed and 65 go back out. The latitudinal heat balance shows how that total is uneven from one latitude to another.