Spatio-temporally continuous temperature monitoring using optical fibers (Loop1) in the internal forest areas at Alaska in 2016

A fiber-optic DTS (distributed temperature sensing) system using Raman-scattering optical time domain reflectometry monitored air, surface, and ground temperatures at a boreal forest research site in the interior of Alaska (Poker Flat Research Range) in parallel experiment settings. A fiber-optic cable sensor (multi-mode, GI50/125,dual-core; 3.4 mm) was deployed across the landscape at high spatiotemporal resolution (0.5 m intervals at every 30 min) with four sub-sections of the cable sensor set in vertical coil configurations (1.2 m high) to facilitate high-resolution measurement of temperature profiles from the subsurface up to one-meter height at approximately 5 mm intervals. The total cable ran 2.3 km within which about a 1.8 km section covered horizontal surface paths. Measurements were made from June 17, 2015, to September 19, 2016 (331 observation days). Interruptions resulted from occasional power shutdowns and subsequent failures in automatic recovery, and from partial failures in the cable sensor.