AI - "Cars measure air temperature using a thermistor, a sensor that changes its electrical resistance with temperature. It's location could be behind the grille, or under a fender.These readings can be inaccurate on hot days because the sensor picks up heat from the road surface, not just the air. On hot, sunny days, the sensor's proximity to the road means it absorbs heat radiated by the asphalt, as well as air temperature. This results in a temperature reading that can be significantly higher than the true air temperature, as it's influenced by both the air and the road's heat."
In the 370Z the sensor is located low in front of the radiator, to keep it away from the heat of the engine. It is a replaceable item.