The present invention provides a thermocouple probe (10). The probe includes a first pair of thermocouple wires (50) joined to form a first thermocouple junction (56) at a sensing tip (14) of the thermocouple probe and a cooling arrangement (20) defining a cooling pathway (34) adjacent to a cooled portion of the probe. The sensing tip projects beyond the cooling arrangement and is cooled during use by conduction to the cooled portion of the probe. The probe further includes a second pair of thermocouple wires (54) joined to form a second thermocouple junction (52) in the cooled portion of the probe and adjacent to the sensing tip. The present invention also provides a method and a system for determining the gas temperature (Tg) in a high temperature environment, such as a jet engine.