Professors Enlist Airborne Lasers to Study Earth's Processes
Federal stimulus will fund imaging project at Critical Zone Observatories throughout U.S.
MERCED, CA— Early next month, airplanes equipped with lasers and high-tech GPS equipment will begin a series of data-gathering flyovers designed to answer many pressing questions about our planet's physical, chemical and biological processes and the ways in which they interact.
Qinghua Guo, a professor in the School of Engineeringat the University of California, Merced, is heading up the project with the help of a three-year, $935,457 grant from the National Science Foundation and fellow professor Roger Bales, director of UC Merced's Sierra Nevada Research Institute. The award is funded by the American Recovery and Reinvestment Act of 2009.
Most of the grant will go toward the contracting of flights that will use Light Detection and Ranging (LiDAR) technology on the NSF's six Critical Zone Observatories(CZOs), a project that has already been featured on the Web site of Scientific American.
The Earth's Critical Zone is the area that stretches vertically from the groundwater to the lowest layer of the atmosphere. Over the past three years, the NSF funded the formation of six CZOs across the United States — including one operated by UC Merced in the Southern Sierra Nevada— that would serve as natural laboratories where top scientists across several disciplines study the many processes that occur within the Critical Zone.
Guo's project will provide scientists throughout the CZO system — and, eventually, the public at large — with remarkably detailed, three-dimensional images of the ground, vegetation and other layers that will help lead to greater understanding of erosion, weathering, soil formation, water movement and nutrient transport.
"Professor Guo's project will provide scientists at CZOs across the country with the data they need to better understand our world and how it works," said Samuel J. Traina, vice chancellor for research. "It gives me great pride to see UC Merced leading the charge in such a valuable, interdisciplinary, multisite endeavor."
LiDAR uses lasers to accurately measure distances to vegetation cover and other layers. Powerful software then aggregates the data into 3D images in which each individual layer can be removed. For example, a layer of trees can be removed to show detailed images of streams and creeks that would otherwise be obscured.
Because data from all six CZOs will be collected using the same method, researchers will be better able to share data and collaborate on their studies with colleagues from other CZOs, Guo said.
"The goal of the CZOs is to build a network to advance interdisciplinary studies of Earth surface processes and foster collaboration among scientists and engineers from different disciplines," Guo said. "This LiDAR data will replace the existing data, which is incomplete, outdated and insufficient in resolution and scale."
Each CZO has its own questions it hopes to answer using the LiDAR data, Guo said. The Southern Sierra CZO, for example, is interested in how vegetation affects the melt and runoff of snow. The LiDAR data will give researchers precise measurements and unparalleled images of the canopy cover of trees, the depth of the snow and the topography of the ground.
Guo said each CZO will get two flyovers. The Southern Sierra CZO will get one set of images with snow and one after the snow melted. Other sites will gather either snow on/off or leaf on/off scenes.
"This will provide a platform for us to study hydrological, geomorphic and biogeochemical questions," Guo said. "All of them rely on this important data."