|
|
~ for immediate release
news release March 31, 2006
Contact: Heather Emmons, DRI PIO, heather.emmons@dri.edu, Reno (775) 673-7313 (w), (702) 743-3435 (c)
Dr. Vanda Grubišić, Principal Investigator, vanda.grubisic@dri.edu,
(775) 247-4724 (cell in the field), (775) 674-7031 (w)
All DRI News Releases are available at: http://news.dri.edu/
DRI scientist leads $9 million international
team research effort to solve meteorological mystery of Sierra
waves and rotors
Research aircraft fly head-on into rough turbulence to gather one-of-a-kind
data to benefit forecasters and pilots alike
|
|
Dr.
Vanda Grubišić embarks on
a research mission on
the King Air research aircraft. |
New
HAIPER aircraft takes off in Denver. |
|
A diagram
showing how the three planes will collect data. |
Reno, Nev.— Armed
with three aircraft, the best data recording equipment and major funding
from the National Science Foundation, a group of more than 60 scientists
from around the world have converged on Owens Valley, Calif., led by
DRI scientist Dr. Vanda Grubišić, to gather new data that
will help forecasters and pilots better understand the turbulent waves
and rotors of the Sierra Nevadas. Scientists,
technicians and graduate students from the Desert Research Institute,
10 U.S. universities, the National Center for Atmospheric Research, the
Naval Research Laboratory and other research institutions from the United
Kingdom, Germany, Austria and Croatia are in Owens Valley through the
end of April, working on a project called the Terrain-Induced Rotor Experiment,
or T-REX, to solve the big mystery of motion within rotor clouds—something
that has never been done before.
Rotors, which form on the lee side of high, steep mountains beneath the
cresting waves of air, have contributed to a number of aircraft accidents, but
scientists know little about their structure and evolution. They are common in
the Sierras because the area has the steepest topography in the continental United
States. Owens Valley sits
some 10,000 feet directly below the highest peaks of the adjacent mountains.
How to gather data in challenging conditions
The system being researched is of great vertical extent, reaching from the ground
to the upper troposphere and lower stratospheric altitudes. Grubišić and
her team are taking the Gulfstream V HIAPER out for its first field experiment,
flying at very high altitudes in the upper troposphere and lower stratosphere.
Accompanying it at the mid-altitude tropospheric levels is the BAe146 jet from
the United Kingdom. And
rounding out the team is the University of Wyoming
King Air turbo-prop aircraft flying closest to the
rotors.
Flying simultaneously over the mountains, the two higher-altitude aircraft
will release GPS dropsondes—small instruments deployed from aircraft to
measure temperature, humidity, pressure and especially winds between the flight
level and the surface (see diagram). As these small boxes with parachutes fall
through the air, they transmit real-time atmospheric profile data back to the
aircraft.
The King Air aircraft, on the other hand, carries an airborne remote sensing
instrument, the Wyoming Cloud Radar, which will allow researchers to see cloud
particles and document the motion within wave and rotor clouds.
On the ground, lidars are looking up from the ground and revealing an incredible
amount of structures in the airflow, "seeing" through dusty air with great detail. Two
Doppler lidars, which measure air motion in addition to producing useful pictures,
will allow scientists to produce maps of the horizontal flow within Owens Valley.
In addition, an aerosol lidar produces incredibly high-resolution images of the
flow.
The three aircraft together with the ground technology help scientists explore
the mountain waves that form over the Sierra Nevada and
are associated with the rotors, as well as study the impacts of the waves on
atmospheric regions as high as the stratosphere. The research will lead to better
prediction of these aviation hazards.
About the King Air
Of the three aircraft being deployed, the King Air has the toughest, most dangerous
missions of all because it is flying through the most turbulent part of the atmosphere
to collect key data. The University of Wyoming's King Air turbo-prop is
equipped with sophisticated meteorological instrumentation and a computer-directed
data display system, which is vital to obtaining precious data during a series
of 25-30 flights it will take throughout the field experiment. It is used
extensively in many of the university's atmospheric science research projects
to obtain on-site atmospheric measurements. The King Air has participated
in a variety of projects worldwide, ranging from relatively small-scale investigations
to large, multi-institutional collaborative efforts.
"The King Air flights thus far have proven to be one of the most exciting aspects
of the project because we have flown nearby and, in some cases, through rotors
collecting excellent research data by in situ sensors and also the cloud radar," said
Grubišić, who has been a mission scientist aboard the aircraft's
data gathering flights.
About the new HIAPER
HIAPER, which stands for High-performance Instrumented Airborne Platform for
Environmental Research, is the nation's newest and most advanced research
aircraft. During the field experiment portion,
it studies a severe type of atmospheric turbulence that forms near mountains
and endangers airplanes. The $81.5 million HIAPER aircraft, owned by the
National Science Foundation and operated by the National Center for
Atmospheric Research (NCAR) in Boulder, Colo.,
will fly over treacherous whirlwinds, known as rotors, as they form above California’s Sierra
Nevada mountain range.
HIAPER is embarking on a series of 10-hour flights that takes it from its
base at Jefferson County Airport in Colorado to California’s Owens Valley during
the T-REX project. The aircraft is ideally
suited for the experiment as it is a highly instrumented Gulfstream V that
is capable of reaching an altitude of 51,000 feet and cruising for 7,000
miles.
"HIAPER's long-range and high-altitude capabilities allow us to collect crucial
new data on the characteristics high up in the atmosphere of atmospheric waves
generated by terrain. These are the same waves that are closely linked
to rotors near the mountain crest," said Grubišić. "In addition,
its communications and data capabilities allow the entire science team of T-REX
to participate in the experiment, whether or not they are actually flying on
board."
Project background
T-REX, funded primarily by the National Science Foundation, is the second phase
of an effort to explore and understand the structure and evolution of atmospheric
rotors and related phenomena in complex terrain. The initial phase of this
effort, the Sierra Rotors Project, took place in Owens Valley two
years ago in March and April 2004. In preparation for that phase, a
long-term network of 16 continuously reporting automatic weather stations
with telemetry was put in place south of Independence, Calif., by Grubisic
in collaboration with DRI’s Western Regional Climate Center (http://www.wrcc.dri.edu/trex). This
network represents the core of the T-REX ground-based instrument suite south
of Independence.
Results of this initial phase and other theoretical and numerical studies
have suggested that rotors are strongly coupled to both the structure and
evolution of overlying mountain waves and the underlying boundary layer.
Consequently, T-REX has been formulated as a comprehensive study of the coupled
system including the mountain wave, the rotor and the boundary layer.
“The goal is to help forecasters predict when and where rotors are most
likely to occur and the degree of their intensity, as well as the nature of the
mountain waves, or gravity waves, that crest high above rotors and cause strong
turbulence,” said Grubišić, who will be a mission scientist
on the two U.S. aircraft.
“Another goal of T-REX is to advance the understanding of the structure
and evolution of rotors in order to improve aviation safety in mountainous terrain,
especially since so many people are moving to the West,” Grubišić pointed
out. “In fact, more and more airports are being
built on the lee sides of mountains – our Reno airport
and the Mammoth Airport north
of Owens Valley in
the eastern Sierra are good examples.
ABOUT DRI: A nonprofit,
statewide division of the Nevada System of Higher Education, DRI pursues
a full-time program of basic and applied environmental research on a local,
national and international scale. Nearly 600 full- and part-time scientists,
technicians, and support staff conduct more than 300 research projects at
DRI annually. DRI generates $45 million in total revenue consisting
predominately of competitively won research contracts and grants. The State
of Nevada provides
critical funding in support of DRI's administration, operations and maintenance,
through the Nevada System of Higher Education's budget. While DRI’s
portion of the NSHE budget is less
than 1 percent, the institute leverages these funds to enhance its competitiveness. |
