Tasseled cap transformation for assessing hurricane landfall impact on a coastal watershed

Abstract

Tasseled cap transformation (TCT) has been used to observe relationships among soil moisture, vegetation cover, and canopy condition. Time series Landsat satellite images of high resolution may provide continuous and accurate observations of the land surface, which can be further analyzed using the TCT for natural hazard events. This study explores the use of a unique dispersion phenomenon of TCT for observing the dynamics of vegetation cover and landscape changes due to a major hurricane landfall in the United States. This is based on the Landsat images taken during the Hurricane Bob event, during which the hurricane made landfall in the highly developed New England area in late August 1991. A unique comparison of the TCT time series plots illustrating the relative TCT dispersion phenomenon, which addresses the landfall’s profound impact on the Mattapoisett River watershed in 1991, reflects the interactions among biosphere, atmosphere, hydrosphere, and lithosphere in hurricane-prone regions. This analysis can be done without the use of ground truth data and can be further supported by the multitemporal and multidimensional change detection of box plots in terms of brightness and greenness to gain more biophysical interpretation. Findings unveil an inherent earth system process via the varying levels of dispersion among brightness, greenness, and wetness over the coastal watershed with environmental sustainability implications.