A change is an event. You can detect a change in temperature. It goes from not changed to changed. The way you would detect the change is by the value changing so you are measuring (not just sensing them but putting them on a scale) the values in order to detect the change.
I think we are in agreement, but just to clarify my point, we can't (or at least shouldn't) say that we detect a temperature. That is, we don't say "we detected a temperature of 35 degrees." The word should be
sensed in a technical context, or
measured in a more colloquial context.
I translate only patents, so my work is heavily skewed to the technical side, but in that field "to sense" is the normal word for this action. That's why we call the device a sensor. A detector detects the presence of something, etc.