Abstract: A floor mat for use over ground in subfreezing climates. The floor mat consists of a planar sheet having an exposed top face, a ground-engageable bottom face, and a peripheral edge portion. A plurality of studs, made from thermally conducting material, are integrally connected to the sheet and project upwardly from its exposed top face. A number of cavities are formed within the sheet in register with the studs, these cavities opening through the sheet bottom face and forming thermal wells. The studs are of such a length as to extend upwardly beyond the layer of ice overlying the floor mat, wherein the top free end tip of the studs will capture sun rays, and transfer radiative heat from the free end tip to the underlying air pocket cavities. Heat will build up in these air pocket cavities, thus promoting radiative transfers to the main body of floor mat, and thus, thaw of ice supported by the floor mat.