Application of differential global positioning systems to monitor frost heave and thaw settlement in tundra environments

Technological advances in Differential Global Positioning Systems (DGPS), used in conjunction with specially designed survey targets, provide a means for accurately detecting frost heave and thaw settlement in cold environments, and for relating positions precisely in worldwide geodetic reference systems. Under ideal conditions, DGPS technology is capable of measuring vertical change of I cm or less. The inexpensive platform targets developed for this study were designed to support a DGPS antenna, to move in concert with the ground surface in response to changes within the active layer, and to function with minimal disturbance. The targets are unlikely to be affected adversely by flooding, cold weather, snow, or animal disturbance. Although the DGPS/target methodology can be strenuous and time consuming in comparison with traditional surveying methods, preliminary results indicate that it can be used to detect frost heave and thaw settlement at very fine resolution. Post-processed rapid static carrier-phase DGPS measured a mean value of vertical heave of I cm and mean subsidence of 4 cm during 2001-2002 at Prudhoe Bay, Alaska. Traditional profile leveling techniques confirmed these measurements. DGPS is a promising tool for measurement of periglacial phenomena, and is applicable over a wide range of spatial scale. Copyright (C) 2003 John Wiley Sons, Ltd.