YOSEMITE — When a television newscast reports two feet of new snow in the Sierra Nevada, you might anticipate a great ski weekend, but standard measurements like those used by TV news can be 20 to 30 percent off the mark on the actual amount of snow in the mountains. To obtain more precise measurements for hydrologic and climate studies, Professor Roger Bales and postdoctoral researcher Bob Rice in the School of Engineering at the University of California, Merced, are using wireless Sensor Webs that are being developed for planetary exploration by NASA's Jet Propulsion Laboratory (JPL) in Pasadena, CA.
"Accurate field data are crucial for scientists exploring links between our water supply and climate," said Bales. "Ultimately, we hope to provide reliable information and analysis to help our communities make better decisions about water use and the ways that humans affect the climate in this region. We think Sensor Webs will be useful tools in gathering that information."
A Sensor Web is a network of interacting sensor pods that share data wirelessly with all other pods in the network, creating a distributed, embedded sensing presence that can react and adapt to changing environmental conditions. JPL contacted Bales and Rice at UC Merced in an effort to find new, earth-bound applications for their technology.
"Sensor Webs provide a versatile way to measure the properties of snow in different locations in mountainous terrain," said Rice. "Previously, the only way to accomplish something similar was to install a data logger with wires going out to sensors around this central location. The wires restricted where we could place our sensors. We have a lot more flexibility with this wireless solution."
Bales and Rice are now using a Sensor Web to record a set of snow properties in the Merced River basin in Yosemite National Park. With this tool, they can take advantage of complex topography to describe the distribution of snow in an area over time by making continuous measurements of precipitation at points with varying slopes, aspects, and vegetation.
UC Merced conducts various types of research in Yosemite National Park as part of a memorandum of understanding between the university and the National Park Service that was signed in 2004.