Improving ease of access to Landsat snowmelt runoff modeling using the commercial cloud environment

Communities in arid regions around the world face an increasing risk of insufficient freshwater availability as mountain snow water equivalent (SWE) levels decline and snowlines retreat with rain-to-snow transitions at mid-elevations. Widespread winter and spring warming coupled with increasing light absorption, due to dust accumulation on the snow, can trigger early snowmelt resulting in earlier peak river discharge introducing more volatility in water availability across the hydrologic year. Modeling and predicting seasonal snowmelt runoff by assimilating remote sensing measures provides a vital tool to help these at-risk communities, yet, access and ease of use of these data and tools continues to be a limitation.

In an effort to improve the ease of access to snow hydrology modeling tools that exploit remote sensing information, previous work in this area over the past several decades has, in part, utilized USGS Landsat data and derived snow cover research products as input to the U.S. Department of Agriculture (USDA)'s Snowmelt Runoff Model (SRM) to prepare model parameters and estimate snowmelt runoff in a number of mountain hydrologic basins worldwide. The SRM characterizes the seasonal snow cover depletion curve derived from remote sensing and then quantitatively solves for daily snowmelt runoff using temperature, precipitation, SWE, and gauged river discharge data inputs.

This study builds off prior work with Landsat and the SRM by building the desktop based SRM within the commercial cloud compute environment (CCCE). Previous work is used as a reference to establish the core functionality of the Landsat-based SRM and seeks to demonstrate its potential for application in any mountain watershed basin using USGS produced Landsat Collection 2 (C2) fractional Snow-Covered Area (fSCA). The improved access through CCCE availability, and improved ease of use through additional automation can broaden impacts to water resource management and decision making where access to these hydrologic region specific tools can aid in better preparation for the foreseen seasonal and decadal snowmelt freshwater availability challenges ahead. This presentation provides an overview of the Landsat C2 fSCA, outlines how the CCCE based SRM operates, and then demonstrates its improvements and capabilities.