A hybrid satellite-ground measurement method for generating snow covered area depletion maps for snowmelt runoff modeling and application to past and present data, and climate change scenarios.

摘要

Snow accumulation and its subsequent melt represent a significant water resource in the world. Snowmelt serves to meet portions of the demand across a wide range of sectors, including domestic, irrigated agriculture, commercial, industrial, recreational, environmental, and power generation uses. Accurate mapping of the areal depletion of snow is therefore vital for operational decision making, for correct specification of boundary conditions in numerical weather-prediction models, and for hydrological and atmospheric modeling. The main objective of this study was to integrate remotely sensed MODIS snow covered area with snow melt-out dates of SNOTEL stations with the aim of developing a tool with a wide range of applications.;Several advanced methods of snow mapping exist today that can be used in determining the progressive reduction of snow cover during snowme however, some of these advanced methods of snow mapping, such as the Moderate-Resolution Imagine Spectroradiometer (MODIS) satellite sensor, were not in existence some years back. The non-availability of MODIS, for example, prior to its launch in 1999 sometimes limits the use of this remote sensing tool in developing historical snow covered area depletion curves that are needed to provide base period perturbations for climate change snowmelt runoff simulations. These historical depletion curves and snowmelt maps, among many other uses, provide snow cover information that enhances our understanding of the historical pattern of snowmelt in any particular watershed. Spatial maps of snow melt-out can also be generated from the information derived from the depletion curves. A method is presented in this study that integrates remotely sensed and ground based data. Apart from generating historical depletion curves, the integration of the remotely sensed snow covered area with the ground truth is also used to investigate and obtain information about the general patterns of snowmelt in the study area and how consistent they are from one year to another. The developed tool coupled with the knowledge of the temporal and spatial consistency of snowmelt patterns are used in the removal of cloud obscuration and generation of snow covered area depletion maps for years predating the launch of MODIS snow cover products.;KEYWORDS: MODIS; SNOTEL; Snow Depletion Curves, Remote Sensing, Snowmelt Patterns, Snowmelt Runoff Simulations.