Selected Recent Publications:

Scanlon, B. R., Goldsmith, R. S., and Langford, R. P., 1999, Relationship between surface geomorphology and unsaturated flow in an arid basin, Chihuahuan Desert, USA: Water Resources Research, v. 35, p. 983–999.

Scanlon, B. R., Tyler, S. W., and Wierenga, P. J., 1997, Hydrologic issues in arid systems and implications for contaminant transport: Reviews in Geophysics, v. 35, p. 461–490.

Scanlon, B. R. , and Milly, P. C. D., 1994, Water and heat fluxes in desert soils-2. Numerical simulations: Water Resources Research, v. 30, no. 3, p. 721–733.

Scanlon, B. R. , 1992, Evaluation of liquid and vapor water flow in desert soils based on chlorine 36 and tritium tracers and nonisothermal flow simulations: Water Resources Research, v. 28, no. 1, p. 285–297.

Condensed Resumé

Environmental Quality

 

Overview

My research employs soil physics, environmental and applied tracers, and numerical modeling to explain flow and transport in unsaturated systems. Soil physics studies, for example, measure spatial and temporal variability in water content and water potential so that we can evaluate current flow processes. We have established monitoring stations to evaluate infiltration and percolation in the Chihuahuan desert and in the Southern High Plains. These stations include thermocouple psychrometers, heat dissipation sensors, and time domain reflectometry probes. We use these monitoring data to validate liquid and vapor transport simulations in response to atmospheric forcing.

We use tracer studies to evaluate flow and transport over longer time periods, hundreds to thousands of years. We have used environmental tracers such as meteoric chloride, chloride-36, tritium, deuterium, and oxygen-18 to quantify water flux and date pore water and we have used applied tracers such as bromide and organic dyes to evaluate preferential flow. Because chloride provides information on net water fluxes for thousands of years, we have used it to examine response of arid regions to variations in plaeoclimate. Bomb pulse 36Cl and 3H data have provided us with information on water fluxes during the past 50 yr and on the importance of liquid and vapor transport in arid regions that was further evaluated using numerical modeling.

My research has concentrated on characterizing flow and transport in natural systems including the relationships between surface geomorphology and unsaturated flow in the Chihuahuan Desert and preferential flow in playas in the Southern High Plains. More recent research evaluates how engineered covers perform in minimizing water movement into waste disposal units. These covers include capillary barriers and asphalt barriers at the Texas low-level radioactive waste disposal facility near Sierra Blanca. Detailed monitoring of soil physical parameters is ongoing at this site.