  Billions of Radio-Frequency Identification (RFID) passive tags are produced
yearly to identify goods remotely. New research and business applications are
continuously arising, including recently localization and sensing to monitor
earth surface processes. Indeed, passive tags can cost 10 to 100 times less
than wireless sensors networks and require little maintenance, facilitating
years-long monitoring with ten's to thousands of tags. This study reviews the
existing and potential applications of RFID in geosciences. The most mature
application today is the study of coarse sediment transport in rivers or
coastal environments, using tags placed into pebbles. More recently, tag
localization was used to monitor landslide displacement, with a centimetric
accuracy. Sensing tags were used to detect a displacement threshold on unstable
rocks, to monitor the soil moisture or temperature, and to monitor the snowpack
temperature and snow water equivalent. RFID sensors, available today, could
monitor other parameters, such as the vibration of structures, the tilt of
unstable boulders, the strain of a material, or the salinity of water. Key
challenges for using RFID monitoring more broadly in geosciences include the
use of ground and aerial vehicles to collect data or localize tags, the
increase in reading range and duration, the ability to use tags placed under
ground, snow, water or vegetation, and the optimization of economical and
environmental cost. As a pattern, passive RFID could fill a gap between
wireless sensor networks and manual measurements, to collect data efficiently
over large areas, during several years, at high spatial density and moderate
cost.
