Across the Earth, the lines of equal global radiation and thus the thermal climate zones have a zonal arrangement. However, this is only ideal for the Cold Zone and the Mid-Latitudes of the Southern Hemisphere.

Particularly above the large continents, the lines of equal global radiation or the thermal climate zones often do not run parallel to the latitude circle. For example, above Tibet an area of highest global radiation can be seen far to the north at a relatively large distance from the equator. In the southern part of Africa, areas of very high global radiation are located much further south than in South America, for example, and in North and Central America much further north than in Europe. The reason for this is the formation of high-pressure areas over extensive land masses that heat up strongly in summer. Low cloud cover ensures high levels of direct solar radiation there.

In contrast, areas with warm, relatively humid ocean currents have a high cloud formation. This reduces direct solar radiation and leads to comparatively low values of global radiation, for example in the coastal areas of the North Atlantic or in East Asia.