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Fiber‐Optic Sensing for Environmental Applications: Where We Have Come From and What Is Possible

The use of fiber‐optic sensors has flourished in many fields over the past 30 years. One particular branch of fiber‐optic sensing, distributed temperature sensing, has become a well‐explored and widely‐accepted tool for a diverse range of environmental applications over the past decade. Peer‐reviewed work on fiber‐optic distributed temperature sensing advanced significantly, moving from innovations in instrumentation, deployment techniques, calibration, and analysis methods to applications. However, exciting advancements in other branches of fiber optics, such as fiber Bragg gratings, optical frequency domain reflectometry, and distributed acoustic sensing, have thus far been underutilized in environmental studies and await exploitation by environmental scientists. These additional techniques offer immense possibilities for novel applications in hydrology, hydrogeology, geophysics, and other environment fields where high‐accuracy, high‐frequency, and/or high spatial resolution measurements are needed.