Comparison of GeoWatch Soil Moisture and Cone Index Predictions with Field Measurements

The state of the ground is important for many applications ranging from agricultural to defense. Creare’s GeoWatch mobility tool currently provides 30 m downscaled geospatial weather-affected terrain conditions and hazards (geowatch@creare.com) on a global scale. Formally known as DASSP, GeoWatch uses a two-stage physically based downscaling technique. Input layers include soil type, land classification, vegetation, weather, and topography. The first stage uses a TOPMODEL approach to calculate the steady-state moisture redistribution while the second phase predicts the dynamic evolution based on weather and vegetation. This redistributed soil moisture along with the USCS (Unified Soil Classification System) engineering soil characterization schema is used to calculate the cone index. The cone index is widely used to assess the soil strength for mobility and maneuver planning due to its measurement ease for most soil types and wetness conditions.

In this presentation we compare the GeoWatch predicted soil moisture and cone index with field data where we simultaneously measured the two properties over a variety of landscapes. Sites ranged from dry-summer subtropical grasslands to mild-summer humid-continental tile-drained agricultural fields. Discussion will explore reasons for observed differences and potential effect on maneuver predictions.