Thermal Remote Sensing of Snow Cover to Identify the Extent of Hydrothermal Areas in Yellowstone National Park

摘要

High resolution airborne multispectral and thermal infrared imagery (1-meter pixel resolution) was acquired over several hydrothermal areas in Yellowstone National Park both in September of 2011 and in early March, during the winter of 2012, when snow cover was still present in most of the Park. The multi-temporal imagery was used to identify the extent of the geothermal areas, as snow accumulation is absent in hydrothermal areas. The presence or absence of snow depends on the heat flow generated at the surface as well as antecedent snow precipitation and temperature conditions. The paper describes the image processing and analysis methodology and examines temperature thresholds and conditions that result in the presence or absence of snow cover.