Distributed Temperature Sensing (DTS) systems provide temperature information for accurate thermal monitoring, fire detection, and condition assessment by utilizing standard fiber optic cables. Temperatures are recorded along the optical sensor cable, thus not at points, but as a continuous profile. Unlike traditional electrical temperature measurement (thermocouples & RTD), the length of the fiber optic cable is the temperature. In distributed temperature sensing (DTS), a single fiber optic cable measures temperature at thousands of points. Our group found its application also possible in environmental sensing.