April 20, 1998 Design News
Engineers help unlock El Niño's secrets
New satellites, sensors,
computers, and software aid in the understanding of
frequently devastating weather phenomenon
by Mark Allan Gottschalk, Western Technical
Huntington Beach, CA--To millions of people and untold
wildlife, the 1997-98 El Niño has meant floods, mudslides,
drought, and even famine. Yet it contains a possible
silver lining for scientists, meteorologists, and engineers.
Delivered along with El Niño's wrath has been increased
emphasis on the need to understand this often destructive
weather phenomenon. This emphasis translates into opportunities
for not only gathering vital information about the most
recent El Niño, but also for developing next-generation
equipment to better understand and forecast El Niños
in the future.
Great. But what exactly is El Niño? The phrase refers
to a massive warming off the coastal waters of Peru
and Ecuador that frequently extends more than 90 degrees
of longitude. It's related to the Southern Oscillation,
the atmospheric component of this phenomenon, and the
two are often abbreviated ENSO. Typically, ENSO starts
late in the spring or summer and builds to a peak at
the end of the year, with the event usually over by
the following summer. It's quasi-periodic, recurring
on an average of two to seven years, and causes significant
anomalous weather effects worldwide.
Vital to El Niño's study are technologies such as satellites,
sensors, instruments, imaging systems, computers, and
software. A sampling of systems and devices available
today and under development include:
ATLAS buoys. These form the Tropical Atmosphere
Ocean (TAO) array in the equatorial Pacific. Next-generation,
ATLAS II buoys just being deployed will extend the
capabilities of the world's only real-time sub-surface
thermal observation system.
Water temperature wizards.
The TAO array, comprised of 70 Autonomous Temperature
Line Acquisition System (ATLAS) buoys, is considered
one of the essential sources of El Niño information.
Their data is more discrete and localized than that
provided by satellites, but the buoys deliver something
no orbital platform can: subsurface water temperatures
The National Oceanic and Atmospheric Administration
(NOAA) is just now mooring the first Next Generation
ATLAS buoys, replacing those placed in the late '80s
and early '90s. Reengineered by the Pacific Marine Environmental
Laboratory (PMEL), changes were made to improve performance
while easing manufacture and reducing cost. Reengineered
buoys function similarly to their predecessors, but
incorporate new electronics and sensors.
Most significant is the incorporation of inductively
coupled sensors clamped directly to the wire-rope mooring
line. This simplifies fabrication over the original
ATLAS which had a separate sensor cable. Sub-surface
temperature readings are supplied by YSI (Yellow Springs,
OH) thermistors, and Paine (Seattle) model 211-30-660-01
pressure sensors determine depth. Interestingly, an
inductive-coupling method is also used to time multiplex
data transmissions from each sensor package to the buoy.
New electronics based on the Motorola MC68332 microprocessor
retrofit into the original electronics packages. This
change greatly reduced component count and improves
reliability. All electronics now fit on a single PCB,
replacing three boards. The board draws an average of
10-15 mW, and a simple battery pack of 84 D-cells will
provide an 18-month deployment life.
Redesigned sensor modules sample and store data at
pre-determined intervals. Their cylindrical housings
are made from polyethylene terephthalate (PET) and designed
for depths up to 750m. Internal electronics are based
on the Motorola MC68HC11 microcontroller with 256K of
RAM. It's mounted to a dense, 8-layer board with surface-mount
components. Three 9V batteries provide power for more
than 400 days.
El Niño vs. big science. "Everyone's
been talking about this El Niño because it just happens
to be the biggest one this century," says Dr. Michael
King, senior project scientist for NASA's Earth Observing
System (EOS), the world's largest science program. Over
the next decade many of EOS' 19 instrument science development
teams and 71 interdisciplinary science investigations
will focus on better understanding ENSO.
One critical piece of El Niño data EOS will provide
is ocean sea-surface vector winds. NASA's SeaWinds microwave
radar scatterometer will launch in 2000 on the ADEOS
II. And a SeaWinds engineering spare will fire aloft
in November 1998 on QuickSCAT, a rapid-development recovery
mission intended to fill in for the Japanese-built ADEOS
I, which failed last June. "Before it failed, the
ENSCAT instrument on ADEOS I was improving some weather
forecasts by 24 hours," says King.
Adding to the El Niño data pile will be MODIS with
its sea-surface temperature and ocean color sensors,
Jason 1 for sea-surface height, and TRMM for tropical
rainfall. On the ground, the EOS Data and Information
System (EOSDIS) ground computers will focus on processing,
analyzing, and disseminating information gathered by
this orbiting army of satellites.
Model behavior. Interpreting this pile of information
is the job of Dr. Lisa Goddard, project scientist at
the International Research Institute (IRI) in San Diego,
CA. "Satellites only tell you what is happening
now, not what will happen in the future," she says,
"that's what prediction models are for."
AT IRI, Goddard and other researchers run El Niño models
developed by organizations such as the National Center
for Environmental Prediction (NCEP) on Cray J90 supercomputers.
Even with 12 processors and gigabytes of RAM, the models
take 2 to 3 days to complete, but it's worth it. "It's
been only quite recently that anyone could make a statement
as to what triggers El Niño, the atmosphere or the ocean,"
says Goddard. "We now know that the inertia for
starting El Niño's is in the ocean."
El Niño Page at NOAA
ATLAS buoy info.
EOS Project Science Office
International Research Institute
AT THE SAE SHOW
Cost major issue among auto engineers
Detroit--As was the case last year, cost concerns dominate
the issues that confront the automotive industry. As
a result, automakers continue to look to technology
innovations for solutions.
That's the finding coming out of a survey of engineers and
designers taken at this year's SAE International Congress
& Exposition. The survey, conducted over the last
four years by the Automotive Consulting Group, Ann Arbor,
for DuPont Automotive, tracks challenges and issues
specific to the global automotive industry.
"Our survey again points to cost as the most sought
after quality in a supplier and the greatest business
issue facing automakers and the supplier community,"
says Erik Fyrwald, director of engineering materials
for DuPont Automotive. "The exciting news is that,
despite these constraints, innovation has managed to
grow and is expected to flourish."
Based on survey results, nearly 100% of respondents
said technology content of vehicles continues to increase.
"The difference now is that we have innovation
with a purpose," Fyrwald adds. "Cost pressures
have forced our industry to examine processes and eliminate
redundancies so that the value of technology is increasingly
outpacing its cost."
One key ingredient for cost control involves systems
integration. And, according to the respondents, complicated
systems demand more stringent engineering standards.
In response, Fyrwald notes, DuPont powertrain system
engineers aggressively pursue the integration of individual
engineering plastic components, such as air-intake manifolds
and valve covers, into multi-functional modules and
systems that lower final assembly costs.
In addition, the survey revealed that 87% of engineers
and designers see a need for more advanced materials.
One way that DuPont has addressed this need involves
the introduction of a new microcut manufacturing technology
for its Vespelr polyimide seal rings. The technology
not only improves performance, says Fyrwald, but reduces
Cost and technology aside, mor