Radio frequency used to communicate by mobile phone has the ability to penetrate through semi-solid substances like meat, and living tissue to a distance proportional to its power density.
It also can cause dielectric heating effect or thermal effect. Thermal effects are the temperature rise in the body cause of energy absorption from oscillating electric fields or electromagnetic radiation.
Thermal radiation is generated when heat from the movement of charged particles within atoms of the mobile phone's case is converted to electro magnetic radiation. Thermal radiation of the mobile phone also related to the specific absorption rate (SAR) where it is defined as the rate of radio frequency (RF) power absorbed per unit mass by any part of the body. SAR values are dependent on the separation distance of the body and the mobile phones. The
nearer the distances of the radiation source to the human head, the higher the SAR values.
Electromagnetic radiation simply deposits its energy by heating the material. This happens both for infrared and non-infrared radiation. Intense radio waves can thermally burn living tissue and can cook food. In addition to infrared lasers , sufficiently intense visible and ultraviolet lasers can also easily set paper afire. Ionizing electromagnetic radiation can create high-speed electrons in a material and break chemical bonds, but after these electrons collide many times with other atoms in the material eventually most of the energy gets downgraded to thermal energy, this whole process happening in a tiny fraction of a second. That infrared radiation is a form of heat and other electromagnetic radiation is not, is a widespread misconception in physics. Any electromagnetic radiation can heat a material when it is absorbed.
Thus to conclude the heating of the ears one feels is due to Electro Magnetic Radiation.