The Study of Precipitation, the Lower Atmosphere and Surface for Hydrometeorology (SPLASH) - Outcomes from the first year of observations

Starting in fall 2021, the NOAA deployed various instruments to the East River watershed around Gothic and Crested Butte, Colorado. These instruments capture observations of the lower atmosphere, surface energy budget, and surface and precipitation properties to support the advancement of weather and water prediction over areas of complex terrain. Led by the NOAA Physical Sciences Laboratory, the SPLASH (Study of Precipitation, the Lower Atmosphere and Surface for Hydrometeorolgy) project leverages collaborations with several NOAA laboratories, universities, NCAR and private industry. In conjunction with the DOE Surface-Atmosphere Integrated Laboratory (SAIL) and Watershed Function SFA, and an NSF-supported study to understand sublimation of snow, SPLASH assets provide one of the most detailed perspectives ever captured of the atmosphere and its interactions with the surface over a single watershed.

Under SPLASH, NOAA has deployed a variety of assets. To monitor clouds and precipitation, there are multiple radars, disdrometers, surface gauges, snow depth sensors, ceilometers, a microwave radiometer, and atmospheric profiler. Together, these systems provide information on precipitation intensity, cloud height, water path, and precipitation size and accumulation. Additionally, these sensors support retrievals of temperature and moisture in the lower atmosphere. In addition to the hydrometeor sensors, NOAA deployed multiple systems capable of providing information on the evolution of the surface energy budget, including two remote surface flux Stations, a 10-meter flux tower, and broadband and spectral irradiance sensors. Additionally, there are systems deployed to measure soil moisture and temperature and aerosol optical depth. Finally, aircraft surveys of soil moisture, snow depth and snow cover have been conducted using both piloted and uncrewed aircraft, and a network of camera systems have been deployed to monitor the snowpack evolution during SPLASH.

SPLASH is scheduled to continue through the summer of 2023. In this presentation, we will provide an overview of the first year of the SPLASH campaign, the observation systems deployed, some initial scientific highlights, and perspectives on future studies.