Tag Archives: Goddard Space Flight Center

AGU 2011: New Map of Antarctica's Rock Bed

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A new, updated map reveals how the Antarctic continent looks under the ice, detailing each mountain range and valley. Beyond its undeniable beauty, this high-resolution map of Antarctica’s bed topography, dubbed BEDMAP2, will help scientists model how ice sheets and glaciers respond to changes in the environment.

A large international consortium of Antarctic field programs, including NASA IceBridge, contributed information to this updated map of bed elevation and ice thickness for Antarctica and the Southern Ocean. The first version of BEDMAP was completed in 2000. The new version, which was presented on Dec. 5 at the American Geophysical Union’s 2011 Fall Meeting, incorporates seismic and radar data from about 265,000 km of airborne surveys over the ice.

“We are lacking fundamental data on ice thickness and bedrock elevation over large parts of Antarctica, because these areas are hard to reach,” said IceBridge project scientist Michael Studinger. “We’ll continue to fill in critical information gaps on places such as the Recovery Glacier in Coats Land, East Antarctica. This area has long been on the wish list of ice sheet modelers, but it is very far away from all research bases.”

This year, IceBridge’s DC-8 aircraft was able to fly four times over Recovery Glacier from Punta Arenas, Chile. “We have collected a landmark data set that will fill a critical hole in new BEDMAP compilations,” Studinger said.

Text by Maria-José Viñas. Image courtesy of the BEDMAP Consortium. The new version of BEDMAP will soon be freely available. Read more about the BEDMAP2 on the project’s website.

4 Views of Eyjafjallajökull’s Plume That You Probably Haven’t Seen Before

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When the volcano roared to life and began spewing huge amounts of ash and gas into the atmosphere, Eyjafjallajökull’s giant plume stranded millions of travelers and captivated the rest of us as it wafted away from Iceland.

Most images have shown how the plume might appear to a human from space. But to an aerosol scientist, the real excitement comes from the instruments that produce less recognizable images that nevertheless reveal subtle details about the nature of the plume.

One instrument or one satellite alone is not likely to yield breakthrough insights about volcanic plumes. Rather, constant comparisons between numerous sets of datacollected by a variety of satellite, aircraft, and ground-based platformsare most likely to lead to new discoveries.

With that in mind, aerosol scientists from NASA’s Goddard Space Flight Center and neighboring institutions met last month at a special AEROCENTER seminar to share information about some aspects of Eyjafjallajökull’s plume that they’ve studied so far.

Such cross-satellite and cross-platform efforts make it possible to address some of the thorniest problems in the field. Comparing results from several instruments, for example, makes it easier to understand the dispersion of plumes and—with the help of computer models—predict how plumes might behave, noted Santiago Gassó, the Goddard geophysicist who organized the seminar.

Though the scientists have just started picking their way through Eyjafjallajökull data, there are a number of presentations from the meeting to click through if you’re interested. There’s nothing Earth-shattering to report yet, but we did find some views of the plume that you likely haven’t seen in the newspapers. You can find more imagery of Eyjafjallajökull’s eruptionand plume here,here, here, here, here, here, and here.


MISR – Plume Height


NASA scientists used an instrument called MISR aboard the Terra satellite to view the ash plume from multiple angles, and then applied a stereo-imaging technique to derive the height of the ash cloud at different points during the eruption. The result is the colorful image on the right that distinguishes plume height with bright reds (6 km), oranges (5 km), yellows (4 km), greens (3 km), and blues (2 km). The blue, near-surface part of the plume is resuspended ash.  (Image Credit: NASA/JPL/MISR)


CALIPSO – Vertical Profile

The CALIPSO satellite provides a vertical profile of a whole slice of the atmosphere with a LIDAR instrument that shoots laser pulses at the atmosphere below and measures how it reflects off particles in the atmosphere. In this image, captured on April 17 as the satellite passed over France, the plume appears as a wispy band of yellow and red. The thick yellow layer below is air pollution hovering near the surface of France. (Image Credit: NASA/CALIPSO/Winker)


OMI – Sulfur Dioxide (SO
2)



The Ozone Monitoring Instrument (OMI) aboard NASA’s Aura satellite had eyes for ash as well as something that’s invisible to the human eye: the transparent (and toxic) gas sulfur dioxide (SO2). OMI observed sulfur dioxide billowing out of the volcano at a clip of as much as 10 thousand tons a day. The OMI instrument produced this image, which shows higher concentrations of sulfur dioxide in red and lower concentrations in blue and purple, on April 30—two weeks after the peak of Eyjafjallajökull’s eruption between April 14 and 17. (Image Credit: NASA/OMI/via Joiner)


DLR Falcon – Aircraft LIDAR


A few days after the eruption began, European scientists scrambled a DLR Falcon jet equipped with a LIDAR and other instruments. The LIDAR, cruising at 8 km altitude, detected volcanic ash in the altitude range of 3.5 km to 5.5 km. The ash plume appears as a yellow and green mass above a layer of clouds (seen as the line of rust-colored spots beneath the ash). When the instrument collected this data, the ash had aged four or five days. The white streaks on the image represent areas where the LIDAR did not detect a significant amount of aerosol. (Image Credit: DLR/via Diehl)

— Adam Voiland, NASA’s Earth Science News Team

Soaring for Science

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NASA's Global Hawk autonomous plane

The newest bird in NASA’s flock — the unmanned Global Hawk — took off at 7 a.m. Pacific time today (April 2) from Dryden Flight Research Center at Edwards Air Force Base in California. The flight is the first airborne checkout of the plane since it was loaded with 11 science instruments for the Global Hawk Pacific (GloPac) mission.

Pilots are also streamlining processes to coordinate the workload while the nearly autonomous plane is flying at altitudes above 60,000 feet (almost twice as high as a commercial airliner). Operators and mission researchers are using the day to make sure all instruments are operating properly while in flight — particularly at the cold temperatures of high altitude — and communicating clearly with the plane and ground controllers. Mission participants expect to begin collecting data when actual GloPac science flights begin over the Pacific Ocean later this month.

GloPac is the Global Hawk’s first scientific mission. Instruments will sample the chemical composition of air in Earth’s two lowest atmospheric layers — the stratosphere and troposphere — and profile the dynamics and meteorology of both. They also will observe the distribution of clouds and aerosol particles. The instruments are operated by scientists and technicians from seven science institutions and are funded by NASA and the National Oceanic and Atmospheric Administration (NOAA).

Paul Newman, the co-mission scientist for GloPac, has been blogging about the mission on Earth Observatory’s “Notes from the Field” site. Here are a few excerpts to whet your appetite…

…There is an old Latin quote: “Maxima omnium virtutum est patientia.” Or “patience is the greatest virtue.” When it comes to mounting science instruments on an aircraft, you need to continually return to that quote…

…During the integration this week, we’ve had to cut holes into the aircraft. I told Chris Naftel, the Global Hawk project manager, that we had to cut some holes into the plane for the Meteorological Measurement System. Chris replied: “I don’t want to hear anything about the holes. It pains me!” In spite of Chris’ pain, the little holes are critical for measuring winds. You’re now asking, what? Little holes? For winds? It’s actually a very slick little measurement that relies on the work of Daniel Bernoulli, a Dutch mathematician who lived in the 1700s…

Read more here …

NASA Readies for Spring 2010 Ice Bridge Campaign

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The following is a cross-post from our sister blog at NASA’s Operation Ice Bridge. For more frequent updates on the Ice Bridge mission, visit https://www.nasa.gov/topics/earth/features/ice_bridge/index.html

Credit: John Sonntag/Wallops Flight Facility

In August 2008, NASA scientist John Sonntag, of NASA’s Wallops Flight Facility in Wallops Island, Va., captured this view of a small iceberg as it moved down the Narsarsuaq fjord in southern Greenland. “I spent about half an hour watching that little berg, which was in the process of disintegrating during the time I was watching,” Sonntag said. “It went from a complete, small berg to a collection of floating ice rubble within that small span of time. The place was so quiet that the noise of the berg softly coming apart was the only sound present.”

Sonntag’s observation took place during the 2008 NASA and Center for Remote Sensing of Ice Sheets (CReSIS) airborne deployment in Greenland. This spring, Sonntag and other scientists return to the Arctic for big picture and little picture views of the ice as part of NASA’s six-year Operation Ice Bridge mission — the largest airborne survey of Earth’s polar ice ever flown — now entering its second year. The project team is finalizing flight paths over Greenland’s ice sheet and surrounding sea ice, where scientists will collect measurements, maps and images from a suite of airborne instruments. Such information will help scientists extend the record of changes to the ice previously observed by NASA’s Ice, Cloud, and land Elevation Satellite (ICESat), while uncovering new details about land-water-ice dynamics.

NASA aircraft have made numerous science flights over Greenland, most recently during the spring 2009 Ice Bridge campaign and also in 2008 as part of the NASA/CReSIS deployment. Smaller-scale airborne surveys have been made by William Krabill, of NASA Wallops, and colleagues nearly every spring since 1991.

Visit the Operation Ice Bridge Web page throughout the spring 2010 campaign for news, images, and updates from the field. Flights from Greenland are scheduled to begin no sooner than March 22.

— Kathryn Hansen, NASA’s Earth Science News Team

The Uphill Road to Measuring Snow

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One-sixth of the world’s population relies on melted snow for their freshwater, which means good estimates of snow are critical for making realistic predictions of a region’s water supply.

But measuring snow, especially the amount of water locked within that snow, challenges researchers across the globe. Why? The two means of estimating snow totals—weather modeling and satellite remote sensing—can vary as much as 30 percent.

Scientists like hydrologist Edward Kim of NASA’s Goddard Space Flight Center continue to seek ways to reconcile the gap between measurement results. Kim and colleagues Michael Durand (Byrd Polar Research Center), Noah Molotch (Univ. of Colorado), and Steve Margulis (UCLA) are wrapping up a short field campaign to measure snow at the Storm Peak Laboratory, perched atop Colorado’s famed mountain at Steamboat Springs.

Their aim is to test and improve the accuracy of satellite-based snow measurements. In the midst of the expedition, they’ve also snapped some breathtaking photos, such as this sun pillar to the right. Sun pillars are typically caused by sunlight reflecting off the surfaces of falling ice crystals associated with certain cloud types.

This post was adapted from NASA’s Earth Observatory. For more updates on the expedition, please visit the Notes From the Field blog.

–Adam Voiland, NASA’s Earth Science News Team