Accurate methods are needed to measure changing soil water content from meter to kilometer scales. Laboratory results demonstrate the feasibility of the heat pulse method implemented with fiber optic temperature sensing to obtain accurate distributed measurements of soil water content. A fiber optic cable with an electrically conductive armoring was...
Over the past five years, Distributed Temperature Sensing (DTS) along fiber optic cables using Raman backscattering has become an important tool in the environmental sciences. Many environmental applications of DTS demand very accurate temperature measurements, with typical RMSE < 0.1 K. The aim of this paper is to describe and...
The Actively Heated Fiber Optic (AHFO) method is shown to be capable of measuring soil water
content several times per hour at 0.25 m spacing along cables of multiple kilometers in length. AHFO is
based on distributed temperature sensing (DTS) observation of the heating and cooling of a buried fiber-optic...
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Rodriguez-Sinobas2, Laureine El Khoury1,
Marshall English1, Nick van de Giesen3, and John S. Selker1
Hydrologic research is a very demanding application of fiber-optic distributed temperature sensing (DTS) in terms of precision, accuracy and calibration. The physics behind the most frequently used DTS instruments are considered as they apply to four calibration methods for single-ended DTS installations. The new methods presented are more accurate than...
The workshop was funded by the National Science Foundation (NSF), OCE Division of Ocean Sciences (Award # 1817257). This report summarizes the key findings, outcomes, and recommendations of the workshop and serves as a draft of the comprehensive roadmap.
Recent developments in Distributed Temperature Sensing (DTS) have allowed new insight into the surface-to-ground water interaction. The continuous temperature measurement by the DTS allows for cool water inflows to be located during warm summer months. These cool water inflows can then be differentiated between ground water and hyporheic exchange. The...
Significant seabird mortality on the Oregon (OR) and Washington (WA) coast in 2009 has been attributed
to a massive bloom of the dinoflagellate Akashiwo sanguinea (K. Hirasaka) G. Hansen & Ø. Moestrup.
Initial, albeit limited, observations suggested this bloom began in WA and reached OR waters through
southward transport. Here,...
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along with all of the volunteers
who tirelessly collected birds for rehabilitation. We also thank Nick
The City of Woodburn, Oregon's Wastewater Treatment Plant (WWTP) has been investigating several natural alternatives for improving effluent quality. Based on its current National Pollution Discharge Elimination System (NPDES) permit, the WWTP will require additional reduction of temperature and ammonia levels in the summer, especially in the critical month of...
The Middle Fork of the John Day River (MFJD) in Northeastern Oregon contains important spawning grounds for spring Chinook and summer steelhead of the Columbia River Basin. In the summer of 2008 phase one of a river restoration project was completed which included the addition of engineered log jams (ELJs)...
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; Tristan, Travis, Mike, Yutaka, Maria, Jim, Chris, Jeff and Ryan. Nick was
a huge help with all of my
Colloids, particles smaller than ten microns in diameter, are ubiquitous in the subsurface. Colloids have an effect on the transport of contaminants that bind to their surfaces, and can reduce the permeability of aquifer materials through deposition. Some microorganisms, including pathogens, are also transported in the subsurface as colloids. The...