SPLASH

Study of Precipitation, the Lower Atmosphere and Surface for Hydrometeorology

About

From fall 2021 through summer 2023, NOAA and research partners participated in the Study of Precipitation, the Lower Atmosphere and Surface for Hydrometeorology (SPLASH). This field study installed a comprehensive, state-of-the-art observing network in the East River watershed of the Colorado mountains with a goal of advancing weather and water prediction capabilities in areas with complex terrain.

Benefits

In combination with scientific analysis of the resulting datasets, research will apply SPLASH observations and the resulting enhanced process-understanding to evaluate and improve NOAA's latest suite of modeling tools, including the Unified Forecast System, Rapid Refresh Forecast System, and National Water Model. The ultimate goal of this project will be improved prediction of weather and water in the Colorado mountains and beyond to inform societal preparedness and response.

Partners

Watch an overview video of the campaign. Transcript

Click to see Actual NOAA Snow Survey Flight Tracks. Topographic image of the 
				Crested Butte–Gunnison region showing the location of SPLASH surface instrumentation and NOAA snow survey flight tracks.
Click map to see NOAA snow survey flight tracks flown in Fall 2021.
Figure. Topographic image of the Crested Butte–Gunnison region, showing the location of SPLASH surface instrumentation (colored icons) and potential NOAA snow survey flight tracks (purple). Together, the SPLASH network and airborne snow survey measurements provide a unique set of observations that can inform seasonal water supply and flood risk outlook.

Follow the Experiment


Social Media

   #SPLASHresearch

SPLASH Data

Data Links and Archived Plots


Dataset references and DOIs

See recent additions and more information on the Zenodo Community SPLASH site.

PSL FTP/Downloads

Site Data Link(s)
Roaring Judy Hourly Met Data (CSV)
Kettle Ponds  Kettle Ponds ASFS
Avery Picnic Area  Avery Data ASFS
Some data and plots are available from the PSL Profiler Network and Image Library Inactive Sites page. Select from Avery Picnic, Brush Creek, Kettle Ponds, and Roaring Judy for site and then select a data type.

SPLASHreach

Meet our Superheroes

Our team is helping researchers measure precipitation to find out more about water availability in a remote mountain basin. Find out how by clicking this image.

SPLASHteam


Bianca Adler
Bianca Adler
PSL | CIRES Research Scientist
Laura Bianco
Laura Bianco
PSL | CIRES Research Scientist
Janice Bytheway
Janice Bytheway
PSL | CIRES Research Scientist
V. Chandrasekar 'Chandra'
V. Chandrasekar "Chandra"
CIRA Fellow
Rob Cifelli
Rob Cifelli
PSL Research Scientist
David Costa
David Costa
PSL | CIRES Engineer
Chris Cox
Chris Cox
PSL Physical Scientist
Ryan Currier
Ryan Currier
PSL Hydrologist
Gijs de Boer
Gijs de Boer
PSL | CIRES Research Scientist
Irina Djalalova
Irina Djalalova
PSL | CIRES Research Scientist
Dan Gottas
Dan Gottas
PSL Research Meteorologist
Jonathan Hamilton
Jonathan Hamilton
PSL | CIRES Research Scientist
Mimi Hughes
Mimi Hughes
PSL Research Scientist
Janet Intrieri
Janet Intrieri
PSL Research Scientist
Francesc Junyent
Francesc Junyent
CIRA Research Scientist
Kathy Lantz
Kathy Lantz
GML Research Scientist
Kelly Mahoney
Kelly Mahoney
PSL Research Scientist
Tilden Meyers
Tilden Meyers
ARL Research Scientist
Sara Morris
Sara Morris
PSL Research Scientist
Annareli Morales
Annareli Morales
PSL | CIRES Research Scientist
Jackson Osborn
Jackson Osborn
PSL Engineer
Laura Riihimaki
Laura Riihimaki
GML | CIRES Research Scientist
Jonah Sandoval
Jonah Sandoval
PSL Engineer
Joseph Sedlar
Joseph Sedlar
GML | CIRES Research Scientist
Elizabeth Smith
Elizabeth Smith
NSSL Research Meteorologist
Allen White
Allen White
PSL Research Meteorologist

Technology

Take a peek at details about some of the observing technologies being used.

PSL researchers Janet Intrieri and Chris Cox installing the ASFS for SPLASH.
PSL researchers Janet Intrieri and Chris Cox installing an ASFS for SPLASH. Credit: Gijs de Boer, CIRES/NOAA

PSL and CIRES designed and built the ASFS to be a moveable instrument system able to power and maintain itself for an extended period of time. It collects atmospheric data that measures all components of the surface energy budget – the exchange of energy between land and atmosphere. By analyzing these measurements, researchers can gain insight into both local and regional weather and climate systems. Learn more

An ASSIST-II instrument
An ASSIST-II unit in the foreground. Credit: Laura Bianco, CIRES/NOAA

PSL and CIRES are installing an ASSIST-II, which is a self-calibrating infrared emission spectroradiometer that allows remote operation, and is used to monitor atmospheric phenomena. It produces high-accuracy atmospheric profiles of various components, such as temperature, moisture, Ozone, Carbon Dioxide, Nitrous Oxide, and more.

The ceilometer installed at Kettle Ponds.
The ceilometer installed at Kettle Ponds. Credit: Joseph Sedlar, CIRES/NOAA

GML, PSL and CIRES are installing ceilometers at Kettle Ponds and Roaring Judy, which are active sensor lidars that emit an eye-safe laser pulse and measure the laser signal as it scatters off aerosols and clouds across the troposphere. These ”backscatter” measurements are analyzed to identify cloud fraction and cloud base heights, and to estimate the planetary boundary layer height.

CLAMPS system
The CLAMPS trailer in August 2020. Credit: NOAA

NSSL is installing the CLAMPS trailer, which is home to three main instruments: a Doppler lidar that sticks out of the roof, a microwave radiometer that pokes out through the side, and an atmospheric emitted radiance interferometer (AERI) that pushes out through the back. The Doppler lidar uses a non-visible laser to measure horizontal and vertical wind speed at high resolution in the lowest parts of the atmosphere. The AERI and microwave radiometer are both passive sensors, meaning they only “listen” for signals. Both instruments measure downwelling radiance from the atmosphere, which is used to retrieve high resolution profiles of temperature and moisture. CLAMPS also has a surface meteorology station to measure the weather conditions right at the surface.

A disdrometer at Kettle Ponds site.
A disdrometer at the Kettle Ponds site. Credit: Dave Costa, CIRES/NOAA

PSL and CIRES are installing disdrometers, which are optical instruments mounted on a tripod that use a laser to measure the size and fall speed of precipitation particles – such as raindrops, snowflakes, or hail – that fall through the laser beam.

the 10-meter micromet and 3-m tripod towers.
10-meter micrometeorological (center), and tripod tower (at left). Credit: Tilden Meyers, NOAA

ARL is installing a 10-meter (33-foot) micrometeorological tower and 3-meter tripod tower at the Kettle Ponds field site. The 10-meter tower is equipped at three levels with instruments that measure wind speed and direction and air temperature. A system at the top of the tower provides observations of turbulence, and the exchange of both heat (or energy) and carbon between the land and atmosphere. One arm has sensors that measure incoming and outgoing long and shortwave and visible radiation, as well as sensors that observe surface temperature. Ground instruments include probes that can detect soil moisture and temperature at various depths between 2-50 cm. The tripod tower has instruments that observe the same variables as the 10-m tower. The tripod is also equipped with sensors to measure snow temperature and density every 10 cm.

A microwave radiometer.
A microwave radiometer. Credit: Laura Bianco, CIRES/NOAA

PSL and CIRES are installing a Radiometrics MP-3000A microwave radiometer at the Roaring Judy field site. This instrument is a passive all-weather atmospheric monitoring system designed to provide continuous real-time profiles of thermodynamic and liquid properties.

The Snow Level Radar installed at Kettle Ponds.
The Snow Level Radar installed at Kettle Ponds. Credit: Dave Costa, CIRES/NOAA

PSL and CIRES are installing two Snow Level Radars, which are vertically pointing radars that transmit a continuous beam of energy and receive backscattered energy from clouds, precipitation, and atmospheric turbulence. The returned signals from precipitation are used to estimate the level in the atmosphere where snow melts and becomes rain, aka, the snow level.

A surface radiation system.
A surface radiation system. Credit: Kathy Lantz, NOAA

GML and CIRES are installing two surface radiation systems to measure the exchange of radiative energy between the atmosphere and the land. These systems consist of several radiometers that passively observe radiation emitted and/or reflected from the atmosphere and the land surface. The radiometers measure radiation at different wavelengths from different directions. Scientists analyze these measurements and derive information on sun, cloud, and surface conditions.

The HELiX on top of a shipping container being prepped for flight.
The HELiX is prepped for flight by Jonathan Hamilton in the Arctic. Credit: Radiance Calmer/CIRES and CU Boulder

HELiX: PSL and CIRES will operate this this rotary-wing aircraft equipped with stabilized up- and downward looking pyranometers. These sensors measure the incident solar energy and when used together they can provide information on the reflectivity of the surface. The downward looking gimbal also includes a multispectral camera that can be used to document snow cover, dust on snow events, and soil and plant properties.


The RAAVEN uncrewed aircraft system in flight
The RAAVEN in flight. Credit: Gijs de Boer, CIRES/NOAA

RAAVEN: CIRES/PSL and CU IRISS will operate this fixed-wing aircraft equipped with the NOAA PSL miniFlux instrumentation. It is set up to measure temperature, pressure, humidity, winds, turbulence and surface/sky temperatures. It can fly for up to two hours at a time and will provide profiles that are assimilated into experimental high-resolution models that target micro- and meso-scale phenomena.


S2: This fixed-wing aircraft is equipped with an L-band radiometer to make measurements of soil moisture. It also carries meteorological sensors and a multispectral camera to document thermodynamic state and winds as well as image the surface and evaluate plant health. It will be operated by Black Swift Technologies, conducting flight patterns prescribed by CIRES/PSL.

The X-Band Radar installed for SPLASH.
The X-Band Radar installed for SPLASH. Credit: Rob Cifelli, NOAA

PSL and CIRA have installed an X-band scanning radar, which detects both liquid and solid precipitation in the atmosphere. During SPLASH, it will be used to determine the type of precipitation – such as raindrops, snow, and graupel – as well as the amount that is falling in a region around the radar. Since there will be a complementary X-band deployed as part of SAIL, the observations from the SPLASH and SAIL radars can be combined to identify the wind patterns in the clouds. Both the precipitation and the wind observations will be used to evaluate forecasts from NOAA’s High Resolution Rapid Refresh model.

Background

Motivation

The Colorado River Basin, a primary source of water for much of the southwestern United States, is estimated to see reductions in runoff ranging between 10% to nearly 50% by mid-century. Persistent dry conditions over the basin combined with warming, have resulted in uncertainty about long-term reliability of the Colorado River Basin as a crucial water source. These stresses, along with growing regional population, enhance the need for careful water resource management, elevating the importance of reliable prediction of river flow and its drivers mirroring important decision making that is required for many river basins across the western United States. Improved observing in the East River watershed supports advanced understanding of processes critical to weather forecasting and water management, and other societally-relevant topics.

Approach

Snowmelt in mountainous headwater regions is the primary contributor of annual basin natural streamflow and water reservoir storage. Given this dependence, some central drivers of Colorado River Basin hydrology and the ability to accurately predict this streamflow include near-surface temperature, precipitation amount, soil moisture, and snowpack properties. Measuring, evaluating, and understanding the contributions and relative uncertainties of these meteorological and hydrologic processes is critical to advancing NOAA’s weather and water prediction capabilities. SPLASH will deploy a variety of sensing systems to observe surface–atmosphere exchange processes, remote and surface sensors to improve understanding of clouds and precipitation, and a collection of observing systems to make detailed measurements of the atmospheric boundary layer. Leveraging ongoing NOAA research, development and operations, and in conjunction with concurrent efforts supported by other agencies, including the U.S. Department of Energy SAIL (Surface-Atmosphere Integrated field Laboratory) campaign and Watershed Function Science Focus Area, SPLASH will provide unprecedented perspectives on some of these critical components to support improved prediction of weather and water over complex terrain.

Colorado River Basin

Map of the Colorado River Basin
Credit: CU Western Water Assessment

Publications

  • Adler, B., J. Wilczak, L. Bianco, L. Bariteau, C.J. Cox, G. de Boer, I. Djalalova, J.M. Intrieri, T. Meyers, J.B. Olson, S. Pezoa, J. Sedlar, E. Smith, D.D. Turner and A. White,2023: Passive remote sensing of the atmospheric boundary layer in Colorado’s East River Valley during the seasonal change from snow-free to snow-covered ground, Journal of Geophysical Research - Atmospheres, 128, e2023JD038497, https://doi.org/10.1029/2023JD038497.
  • de Boer, G., A. White, R. Cifelli, J. Intrieri, M. Hughes, K. Mahoney, T. Meyers, K. Lantz, J. Hamilton, W.R. Currier, J. Sedlar, C. Cox, E. Hulm, L.D. Riihimaki, B. Adler, L. Bianco, A. Morales, J. Wilczak, J. Elston, M. Stachura D. Jackson, S. Morris, V Chandrasekar, S. Biswas, B. Schmatz, F. Junyent, J. Reithel, E. Smith, K. Schloesser, J. Kochendorfer, M. Meyers, M. Gallagher, J. Longenecker, C. Olheiser, J. Bytheway, B. Moore, R. Calmer, M.D. Shupe, B. Butterworth, S. Heflin, R. Palladino, D. Feldman, K. Williams, J. Pinto, J. Osborn, D. Costa, E. Hall, C. Herrerab, G. Hodges, L. Soldo, S. Stierle, and R.S. Webb, 2023: Supporting Advancement in Weather and Water Prediction in the Upper Colorado River Basin: The SPLASH Campaign, Bull. Amer. Meteor. Soc., accepted for publication, https://doi.org/10.1175/BAMS-D-22-0147.1
  • Feldman, D.R., A.C. Aiken, W. R. Boos, R. Carroll, V. Chandrasekar, S. Collis, J. Creamean, G. de Boer, J. Deems, P. J. DeMott, J. Fan, A. N. Flores, D. Gochis, M. Grover, T. Hill, A. Hodshire, E. Hulm1, C. Hume, R. Jackson, F. Junyent, A. Kennedy, M. Kumjian, E. Levin, J. D. Lundquist, J. O’Brien, M. S. Raleigh, J. Reithel, A. Rhoades, K. Rittger, W. Rudisill1, Z. Sherman, E. Siirila-Woodburn, S. M. Skiles, J. N. Smith, R. C. Sullivan, A. Theisen, M. Tuftedal, A. C. Varble, A. Wiedlea, S. Wielandt, K. Williams, Z. Xu, 2023: The Surface Atmosphere Integrated Field Laboratory (SAIL) Campaign, Bull. Amer. Meteor. Soc., accepted for publication, https://doi.org/10.1175/BAMS-D-22-0049.1.