NASA Tracks Snowmelt to Improve Water Management

Publicerad denFörfattareRss .

As part of a science mission tracking one of Earth’s most precious resources – water – NASA’s C-20A aircraft conducted a series of seven research flights in March that can help researchers track the process and timeline as snow melts and transforms into a freshwater resource. The agency’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) installed on the aircraft collected measurements of seasonal snow cover and estimate the freshwater contained in it.
“Seasonal snow is a critical resource for drinking water, power generation, supporting multi-billion dollar agricultural and recreation industries,” said Starr Ginn, C-20A project manager at NASA’s Armstrong Flight Research Center in Edwards, California.  “Consequently, understanding the distribution of seasonal snow storage and subsequent runoff is essential.”
The Dense UAVSAR Snow Time (DUST) mission mapped snow accumulation over the Sierra Nevada mountains in California and the Rocky Mountains in Idaho. Mission scientists can use these observations to estimate the amount of water stored in that snow.

“Until recently, defining the best method for accurately measuring snow water equivalent (SWE) – or how much and when fresh water is converted from snow – has been a challenge,” said Shadi Oveisgharan, principal investigator of DUST and scientist at NASA’s Jet Propulsion Laboratory in Southern California. “The UAVSAR has been shown to be a good instrument to retrieve SWE data.”
Recent research has shown that snow properties, weather patterns, and seasonal conditions in the American West have been shifting in recent decades. These changes have fundamentally altered previous expectations about snowpack monitoring and forecasts of snow runoff. The DUST mission aims to better track and understand those changes to develop more accurate estimates of snow-to-water conversions and their timelines.
“We are trying to find the optimum window during which to retrieve snow data,” Oveisgharan said. “This estimation will help us better estimate available fresh snow and manage our reservoirs better.”

The DUST mission achieved a new level of snow data accuracy, which is partly due to the specialized flight paths flown by the C-20A. The aircraft’s Platform Precision Autopilot (PPA) enables the team to fly very specific routes at exact altitudes, speeds, and angles so the UAVSAR can more precisely measure terrain changes.
“Imagine the rows made on grass by a lawn mower,” said Joe Piotrowski Jr., operations engineer for NASA Armstrong’s airborne science program. “The PPA system enables the C-20A to make those paths while measuring terrain changes down to the diameter of a centimeter.” Läs mer…

Testing in the Clouds: NASA Flies to Improve Satellite Data

Publicerad denFörfattareRss .

In February, NASA’s ER-2 science aircraft flew instruments designed to improve satellite data products and Earth science observations. From data collection to processing, satellite systems continue to advance, and NASA is exploring how instruments analyzing clouds can improve data measurement methods.
Researchers participating in the Goddard Space Flight Center Lidar Observation and Validation Experiment (GLOVE) used the ER-2 – based at NASA’s Armstrong Flight Research Center in Edwards, California – to validate satellite data about cloud and airborne particles in the Earth’s atmosphere. Scientists are using GLOVE instruments installed onboard the aircraft to measure and validate data about clouds generated by satellite sensors already orbiting in space around Earth.
“The GLOVE data will allow us to test new artificial intelligence algorithms in data processing,” said John Yorks, principal investigator for GLOVE and research physical scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “These algorithms aim to improve the cloud and aerosol detection in data produced by the satellites.”

The validation provided by GLOVE is crucial because it ensures the accuracy and reliability of satellite data. “The instruments on the plane provide a higher resolution measurement ‘truth’ to ensure the data is a true representation of the atmospheric scene being sampled,” Yorks said.
The ER-2 flew over various parts of Oregon, Arizona, Utah, and Nevada, as well as over the Pacific Ocean off the coast of California. These regions reflected various types of atmospheres, including cirrus clouds, marine stratocumulus, rain and snow, and areas with multiple types of clouds.
“The goal is to improve satellite data products for Earth science applications,” Yorks said. “These measurements allow scientists and decision-makers to confidently use this satellite information for applications like weather forecasting and hazard monitoring.”

The four instruments installed on the ER-2 were the Cloud Physics Lidar, the Roscoe Lidar, the enhanced Moderate Resolution Imaging Spectroradiometer Airborne Simulator, and the Cloud Radar System. These instruments validate data produced by sensors on NASA’s Ice, Cloud, and Land Elevation Satellite 2 (ICESat-2) and the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE), a joint venture between the ESA (European Space Agency) and JAXA (Japan Aerospace Exploration Agency).
“Additionally, the EarthCARE satellite is flying the first ever Doppler radar for measurements of air motions within clouds,” Yorks said. While the ER-2 is operated by pilots and aircrew from NASA Armstrong, these instruments are supported by scientists from NASA Goddard, NASA’s Ames Research Center in California’s Silicon Valley, and the Naval Research Laboratory office in Monterey, California, as well as by students from the University of Iowa in Iowa City and the University of Maryland College Park. Läs mer…