Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA HS3 Instrument Views 2 Dimensions of Clouds

17.09.2014

Looking out the window of a commercial plane during takeoff is like taking the nickel tour of the profile of the atmosphere. As the plane ascends, what may start as a gloomy day on the ground, can turn into rain streaking across the window as you pass through the white-gray cloud, and then sunny skies above once the plane reaches cruising altitude.

NASA’s Cloud Physics Lidar (CPL) instrument, flying aboard an unmanned Global Hawk aircraft in this summer’s Hurricane and Severe Storm Sentinel, or HS3, mission, is studying the changing profile of the atmosphere in detail to learn more about how hurricanes form and strengthen.


Image Credit: NASA's Goddard Space Flight Center/R. Fitzgibbons

“CPL profiles the atmosphere to get a two-dimensional picture of cloud and aerosols, from the top down,” said Matt McGill of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who led the instrument team that designed and built the CPL. Its data, presented as if it were a curtain hanging from the sky, shows what’s in the atmosphere’s different layers.

From about 60,000 feet on the Global Hawk, twice the altitude of a commercial plane, 94 percent of the atmosphere lies below the instrument. The lidar works by sending rapid pulses of light that, like a radar beam, bounce and scatter off any particles they encounter, such as cloud droplets or dust particles. Some of the scattered light returns to the instrument where it records how long it took for the photons to leave and return – giving the altitude of the particles.

CPL sends out 5,000 pulses of light per second in three different wavelengths, allowing the science team to discriminate between different types of particles, McGill said. “Is it a cloud made of water? Is it a cloud made of ice or mixed [water and ice]? And we can say something about what type of airborne particle we are seeing. Is it dust or smoke or pollution?”

For the scientists studying hurricanes, those distinctions are important. One of the major areas of study is how Saharan dust off of Africa travels across the Atlantic and affects hurricane formation and intensification. CPL data have been used to verify model projections of Saharan dust in the tropics. The CPL data showed dust layers had a vertical distribution different than models predicted. Instead dust layers occupied narrower altitude ranges. The finding led to an improvement in the dust models, which then feed into hurricane models.

Situated in the nose of the Global Hawk flying over the storm environment, CPL also has a role in on-the-fly mission planning. While in flight, the CPL sends its data back to the team on the ground. “The mission scientists involved in the flight planning can sit there and watch the data with us in real time and say, ‘Oh, we’re not getting what we want.’ Then they can go work with the flight planners and pilots to reroute the aircraft into different areas,” said McGill. “They love that.” 

The airborne science community takes full advantage of the quick look capability, as well as the 24-hour turn around for the final data products. CPL is one of the most flown instruments in NASA’s Earth science fleet. “It’s a workhorse for the field campaigns,” said McGill.

The original CPL was built in 1999 and took its first flight on the ER-2 high altitude research aircraft in 2000. Over the years CPL has been used as a satellite simulator for ground validation efforts, a cloud spotter for other instruments needing a clear view of the ground, as well as the main data collector for scientists studying atmospheric composition and Earth’s energy budget where thin clouds and aerosols are major players. The lidar was also part of the proof of concept flights for the A-Train, a series of satellites flying in the same orbit making near-simultaneous measurements of the Earth system using many different instruments. That proof of concept airborne campaign showed scientists the power of combining multiple Earth observing data sets.

In 2007, when talk began of using Global Hawks for Earth science, CPL was among the first sensors considered; its size is perfect for the instrument compartment. Worries about the untested Global Hawk led to a second nearly identical instrument being built for use on the unmanned aircraft. It flew on NASA’s maiden Global Hawk Pacific campaign in 2009. Since then, the Global Hawk CPL has flown in two multi-year campaigns, alternating between the Airborne Tropical Tropopause Experiment (ATTREX) and HS3.

Compact and fully autonomous, the CPL lidar design pioneered photon-counting technology that has led to the development of two instruments that will fly in space, the Cloud-Aerosol Transport System (CATS), which launches to the International Space Station this December, and the Advanced Topographic Laser Altimeter System (ATLAS), which will fly on the Ice, Cloud and land Elevation Satellite-2 (ICESat-2) scheduled to launch in 2017.

The solid design of the instrument has borne up surprisingly well over the years, said McGill, who uses CPL as a learning tool for interns and young scientists getting their hands dirty in the field. Together, the twin CPL instruments have flown 26 missions. HS3 will mark the 27th overall and the seventh for the Global Hawk CPL.

“It’s still going strong,” McGill said.

The HS3 mission is funded by NASA Headquarters and overseen by NASA’s Earth System Science Pathfinder Program at NASA’s Langley Research Center in Hampton, Virginia, and is one of five large field campaigns operating under the Earth Venture program. The HS3 mission also involves collaborations with partners including the National Centers for Environmental Prediction, Naval Postgraduate School, Naval Research Laboratory, NOAA’s Hurricane Research Division and Earth System Research Laboratory, Northrop Grumman Space Technology, National Center for Atmospheric Research, State University of New York at Albany, University of Maryland - Baltimore County, University of Wisconsin and University of Utah. The HS3 mission is managed by the Earth Science Project Office at NASA’s Ames Research Center in Moffett Field, California.

Related Links
 

Ellen Gray | Eurek Alert!
Further information:
http://www.nasa.gov/content/goddard/nasa-hs3-instrument-views-2-dimensions-of-clouds/

More articles from Earth Sciences:

nachricht NASA sees the end of ex-Tropical Cyclone 02W
21.04.2017 | NASA/Goddard Space Flight Center

nachricht New research unlocks forests' potential in climate change mitigation
21.04.2017 | Clemson University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>