Abstract: The invention relates to a method and a device for monitoring, also permanently and automatically, temperature distributions and/or temperature anomalies on the basis of distributed fiber-optic temperature sensing as well as to the use of such methods. According to the invention the detection of local temperature extremes, i.e. minimums or maximums, in view of the evaluation is performed by an evaluation without numeric derivations. With the device for monitoring ascending and supply pipes surrounded by an annular space it is possible to check the safety of pressurized installations, particularly in the field of low-pressure gas storage, in a cost-efficient manner. Moreover, the position of an underground watershed or respectively the direction and flow rate of the flows in flooded drift sections can be determined on the basis of fiber-optic temperature measurements.