Land surfaces warm and cool much quicker than water bodies, leading to differential heating of the Earth’s surface.

Differential heating

• The curvature of the Earth results in spreading out of solar energy towards the poles and a concentration near the equator.
• The curvature of the Earth results in solar energy having a larger amount of atmosphere to travel through to reach the Earth’s surface near the poles than towards the equator.

Differential heating- differences in the amount of heat received when different surfaces are heated by the sun. a) Light surfaces heat less than dark surfaces. Example: snow will heat less than soil b) The sun’s energy is spread out over a large area, so it heats the Earth’s surface unevenly.

Differential heating is the disparity in heating of air over land versus water. The high pressure air from the sea influxes, creating a sea breeze. This can lead to thunderstorms when moist air rises and sea breezes collide, or monsoons in tropical areas, seasonal sea breezes that bring heavy rain.

The sea has a greater heat capacity than land, so the surface of the sea warms up more slowly than the land’s. As the temperature of the surface of the land rises, the land heats the air above it by convection.

Solar heating of the Earth’s surface is uneven because land heats faster than water, and this causes air to warm, expand and rise over land while it cools and sinks over the cooler water surfaces. This differential heating is passed on to the air above by conduction which causes air expansion and changes in pressure.

Wind is the movement of air caused by the uneven heating of the Earth by the sun. Warm equatorial air rises higher into the atmosphere and migrates toward the poles. This is a low-pressure system. At the same time, cooler, denser air moves over Earth’s surface toward the Equator to replace the heated air.

The factors that contribute to the uneven heating of the Earth by the sun include latitude, seasons, and the time of the day.

Earth’s orbit around the sun and its rotation on a tilted axis causes some parts of Earth to receive more solar radiation than others. This uneven heating produces global circulation patterns. For example, the abundance of energy reaching the equator produces hot humid air that rises high into the atmosphere.

In summer, near the equator the land warms up faster and most of the time the temperature of the land is higher than that of water in the oceans. The air over the land gets heated and rises. This causes the winds to flow from the oceans towards the land.

The heat source for our planet is the sun. Energy from the sun is transferred through space and through the earth’s atmosphere to the earth’s surface. Since this energy warms the earth’s surface and atmosphere, some of it is or becomes heat energy.