Analysis of snow water equivalent data needs and capabilities

Global snow cover is an integral part of the Earth’s water and energy cycles, contributing life-giving water resources to billions of people around the world while helping to cool the planet by reflecting solar energy back to space.  Accurate measurements of snow at a regional scale are needed to improve runoff predictions to inform water supply and hydropower needs and to help predict conditions that are associated with floods, drought, and wildfires. Though we can measure the extent of snow cover globally, we cannot yet reliably measure the amount of water stored in a snowpack, or snow-water equivalent (SWE) from space at the resolution and accuracy needed to understand its role in the water cycle. In addition, it is uncertain how the extent and the volume of snow will be changed across the globe in a warmer climate. Here we will review the snow data needs to address our most pressing science questions and operational requirements. We will also present the results of a coverage analysis of SWE data from currently-available and upcoming sensors over the northern hemisphere to identify gaps in current capabilities.