Thermal equator
The thermal equator (also known as "the heat equator") is a belt encircling Earth, defined by the set of locations having the highest mean annual temperature at each longitude around the globe. Because local temperatures are sensitive to the geography of a region, mountain ranges and ocean currents ensure that smooth temperature gradients (such as might be found if Earth were uniform in composition and devoid of surface irregularities) are impossible; thus, the location of the thermal equator is not necessarily identical to that of the geographic Equator.