Soil and meteorological conditions hamper improvised explosive device (IED)/mine detection yielding inconsistent and in some cases unacceptable probability of detection (PD) and false alarm rates (FAR). To assess and identify the environmental parameters impacting standoff thermal infrared (IR) utilization over varying temporal and spatial scales a three-month study evaluated the associated degree of variance. The lessons learned include; 1) the considerable spatial variance in surface soil temperatures at varying scales of observation, 2) spatial and temporal impact of buried objects on the thermal signature of soil, 3) identification of the environmental parameters impacting the thermal spatial and temporal temperature variance for disturbed and undisturbed soil, and 4) development of a data analysis technique taking into account temperature variance (ΔT) over time (Δς) as a approach to assess buried objects.
The environmental phenomenological properties responsible for the thermal variability evident in the use of thermal infrared (IR) sensor systems is not well understood. The research objective of this work is to understand the environmental and climatological properties contributing to the temporal and spatial thermal variance of soils. We recorded thermal images of surface temperature of soil as well as several meteorological properties such as weather condition and solar irradiance of loamy soil located at the Cold Regions Research and Engineering Lab (CRREL) facility. We assessed sensor performance by analyzing how recorded meteorological properties affected the spatial structure by observing statistical differences in spatial autocorrelation and dependence parameter estimates.