April 4, 2013
NASA Studies South America’s Volcanoes, Glaciers And Deserts With Microwave Energy
Lawrence LeBlond for redOrbit.com - Your Universe Online
A NASA aircraft carrying the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) is finishing up a month-long mission to address a broad range of scientific questions over the Americas, including the dynamics of the Earth´s crust, glaciers and the carbon cycle.
The flights began on March 7 from NASA´s Dryden Aircraft Operations Facility in Palmdale, California and observed areas of the Earth from the Gulf Coast to South America, including Argentina, Bolivia, Chile, Colombia, Costa Rica, El Salvador, Ecuador, Guatemala, Honduras, Nicaragua and Peru.
The UAVSAR, which was designed, built and is managed by NASA´s Jet Propulsion Laboratory (JPL) in Pasadena, California, uses a technique called interferometry that sends microwave energy pulses from the sensor on the aircraft to the ground. The technique has the ability to detect and measure the most subtle changes in Earth´s surface, like those caused by earthquakes, volcanoes and glacier movements. The radar´s L-band microwaves can penetrate clouds and forest canopies, giving scientists a better look at cloud-covered tropical environments, and allowing for the mapping of flooded ecosystems.
Naiara Pinto, a UAVSAR science coordinator at JPL, said the campaign shows off the versatility of the instrument for studies of Earth.
"In many cases, study sites are being used by multiple investigators. For example, some volcanic sites also have glaciers. The studies also help U.S. researchers establish and broaden scientific collaborations with Latin America," Pinto said in a statement.
Images taken by UAVSAR will help volcano scientists make comparisons with new imagery slated for collection in 2014. By comparing the two sets of imagery, scientists will be able to measure very subtle changes in the surface associated with the movement of magma at depth beneath active volcanoes.
Results of these studies are expected to improve models used to understand and mitigate volcanic hazards. The UAVSAR program is observing volcanoes in several South American countries.
The UAVSAR instrument has also been imaging glacier data in the Andes Mountains, and data from that region will be combined with measurements as well as airborne LIDAR data to determine how much these glaciers move not only during the summer, but on a year-to-year scale.
The program has also involved leadership by the US Geological Survey (USGS) and the Chilean government in the study of the glacier processes. The work will offer a better understanding of how these glaciers react in the face of climate change impacts from human activities. The glaciers that were imaged by UAVSAR provide freshwater for residents of Santiago and also water for agriculture across the region.
The instrument has also been directed at coastal mangroves in Central and South America, to aid in the study of coastal environments.
"Much of Earth's population lives along coasts, and its livelihood and well-being depend on services provided by marine ecosystems," said JPL's Marc Simard, one of the campaign's many principal investigators. "These regions are among the most fragile on Earth. It is critical to understand how the interactions of human activities and climate change may impact the sustainability of these ecosystems."
Other areas studied during the month-long mission were of the Amazon River basin and Pacaya-Samira National Park in Peru. Kyle McDonald, of JPL and the City University of New York (CUNY), led data collections for these regions, which will help with mapping of the regions wetlands.
"Pacaya-Samiria contains large expanses of flooded palm swamps," McDonald said. "These ecosystems are potential major sources of atmospheric methane, an important greenhouse gas. UAVSAR will help us better understand processes involved with the exchange of methane between Earth's land and atmosphere, and with the contribution of these unique ecosystems to Earth's climate."
Also, UAVSAR is supporting agricultural studies of Chile´s vineyards in the La Serenas region. These studies will assist scientists working at the Universidad de La Serena´s Terra Pacific Group to better understand the value of soil moisture data for grape and wine production.
UAVSAR imaging is also aiding in collaboration between Thomas Jackson of the USDA and Argentina´s Comision Nacional de Actividades Espaciales (CONAE). Their studies will assist in the preparation for a project known as NASA´s Soil Moisture Active Pass (SMAP) satellite due to launch in 2014.
Imaging of the northern coastal Peruvian desert, where the Moche culture thrived nearly two millennia ago, will aid researchers in the search for unrecorded archaeological features in an attempt to preserve sites from encroaching civilization.
Also, UAVSAR imaging is aiding in the study of structure, biomass and diversity of tropical cloud forests in the Peruvian Andes and Manu National Park. This work is being led by JPL researcher Sassan Saatchi, who has been studying the region for the past decade. Data collected from UAVSAR will be used to evaluate how much carbon the forests contain and assess their vulnerability to disturbances caused by both man and nature.
Besides conducting impassioned research over South America, NASA has directed the instrument at sites in the US as well. UAVSAR has been monitoring seasonal land subsidence and uplift in groundwater basins in Arizona´s Cochise County for the Arizona Department of Water Resources, and has conducted similar studies in New Orleans and the Mississippi Delta.
These studies are aimed at offering scientists a better understanding of what causes Gulf Coast subsidence and allowing for better predictions of future subsidence rates. The data will help agencies better manage the protection of infrastructure, including the levee system in the New Orleans region.
Image Below (Left): This false-color image of Colombia's highly active Galeras Volcano, acquired by NASA´s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) on March 13, 2013, details a breached caldera and an active cone that produces numerous small to moderate explosive eruptions. By comparing these camera-like images taken at different times, interferograms are generated that reveal changes in Earth's surface caused by volcanic deformation. NASA's C-20A environmental research aircraft carrying the UAVSAR will precisely fly the same flight path over the volcano in 2014. Credit: NASA/JPL-Caltech
Image Below (Right): This false-color image created from data obtained by NASA´s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) over the Napo River in Ecuador and Peru on March 17, 2013, indicates the likelihood of flooding beneath the forest canopy. Red and yellow shades indicate a high likelihood of standing water with emergent vegetation, blue and green shades are areas less likely to be inundated, and black indicates the open water areas of the Napo River. UAVSAR data like these are helping scientists assess the effectiveness of using synthetic aperture radar data to study the inundation dynamics of this and similar rivers around the world. Credit: NASA/JPL-Caltech