What is SnowEx?
SnowEx is a five year program initiated and funded by NASA THP to address the most important gaps in snow remote sensing knowledge. It focuses on airborne campaigns and field work, and on comparing the various sensing technologies, from the mature to the more experimental, in globally-representative types of snow. The goal is to address the most important gaps in our snow remote sensing knowledge, and thus lay the groundwork for a future snow satellite mission.
What is the geographical focus of SnowEx?
The geographical focus of SnowEx is proposed as North America (Fig. ES1, SnowEx Science Plan), which contains the six broad snow climate categories identified in the literature: tundra (alpine or Arctic), taiga (Boreal forest), warm (temperate) forest, maritime, prairie, and ephemeral. Additional factors that transcend these snow climates include terrain complexity (e.g., steep vs. flat terrain), and snow states like wetness. The timing and location of specific campaigns is envisioned as a combination of opportunistic as well as targeted choices, and planned to leverage complementary or similar airborne and field efforts external to SnowEx. Specifically, SnowEx leveraged Airborne Snow Observatory (ASO) operations (2013-ongoing) in the 2016-2017 northern hemisphere winter in Colorado and will do so again in the 2019-2020 winter over a broader domain that also includes California and Idaho. Also, in the 2019-2020 winter, SnowEx will extend coverage to snow in boreal forests and Arctic tundra in conjunction with the NASA ABoVE campaign (2014-2024). The final field campaign is proposed to address remaining gaps: we describe two candidate sites, one in the cold prairies of the northern contiguous United States and southern Canada, which presents an opportunity to test snow remote sensing techniques in an environment that is extensive globally, and one in the maritime zone of the Pacific Northwest, which presents an opportunity to test snow remote sensing techniques in a unique environment with multiple sensing challenges (deep snow, wet snow, persistent cloud cover, and dense forests). Discussions on the focus of SnowEx 2021 are still ongoing.
What are the SnowEx outcomes and International Engagement:
SnowEx will provide key insights into optimal strategies for mapping global SWE with remote sensing and models, which will enable a competitive proposal for a Decadal Survey “Earth System Explorer” mission. The systematic assessment of methods for mapping water and energy components of seasonal snow in SnowEx is fully aligned with the objectives of the NASA Terrestrial Hydrology Program and the Earth Science Division as well as the ESDS. As any future snow satellite mission will require observations from an international collection of satellites, engagement with the international snow science community is central to the success of SnowEx. Realization of a global snow mapping program requires coordination with international partners and space agencies (e.g., Canada, Europe, China). SnowEx is directly responsive to recommendations from the international community (e.g., World Meteorological Organization) to test snow measurement techniques across vegetation gradients and climates, and to develop systems that incorporate models and remote sensing data to characterize snowpack states.
SnowEx/year-1 Science Traceability Matrix (STM).
Why do we need SnowEx?
Download the PDF.
If you are interested in the future of snow remote sensing, we encourage you to join the SnowEx effort. Help us to design and execute SnowEx--to work towards a future snow satellite mission while also enabling critical, innovative, ground-breaking science at the same time. If you’d like to be added to the SnowEx email list, please contact Charles Gatebe.