 The mean heat loss from Earth is 87 mW m − 2 , for a global heat loss of 4 @.@ 42 × 1013 W. A portion of the core 's thermal energy is transported toward the crust by mantle plumes ; a form of convection consisting of upwellings of higher @-@ temperature rock . These plumes can produce hotspots and flood basalts . More of the heat in Earth is lost through plate tectonics , by mantle upwelling associated with mid @-@ ocean ridges . The final major mode of heat loss is through conduction through the lithosphere , the majority of which occurs under the oceans because the crust there is much thinner than that of the continents . 
