H E AT T R A N S F E R
AND THE
MOVEMENT
OF
AIR
MATTHEW BAILEY/NSRC
LESSON 4
WHAT’S THE
FORECAST?
Researching the Weather
Although many people watch Bob Ryan on television, he is more than a television reporter. As
a meteorologist, Ryan is a scientist who studies
weather data and model predictions from the
National Center for Environmental Prediction
(NCEP). Through NCEP, Ryan has access to
data from more than 3500 weather stations.
Every hour, these stations provide information
on air temperature, air pressure, wind direction
and speed, relative humidity, and precipitation.
Ryan also uses Doppler radar to detect how
air is moving. How does Doppler radar work?
Think of the sound a train makes as it
approaches. As it gets nearer to you, the pitch
of the sound gets higher. As it moves away, the
pitch gets lower. Doppler radar works something like that. If the Doppler frequency is
increasing, a storm is moving toward the radar.
If the frequency is decreasing, a storm is moving away from the radar. Doppler radar has
enabled forecasters like Ryan to provide people
with early warnings of potential danger.
50 STC/MS™ C ATA S T R O P H I C E V E N T S
Bob Ryan, meteorologist and TV weather
forecaster
Why is radar so important to the study of
thunderstorms, high winds, and tornadoes?
Radar is important primarily because these
storms cannot be seen from satellites, and they
can develop very quickly.
Satellites are also important tools for Ryan.
Satellites orbiting in space take pictures of
clouds covering the earth. A series of pictures
over time can show meteorologists how a large
storm, such as a hurricane, moves and can help
predict the path it might take.
NOAA/DEPARTMENT OF COMMERCE
What will the weather be like today? Many of
us want to know, so we turn on the television to
see what the weather forecasters have to say. In
the Washington, D.C., area, we may be tuning
in to meteorologist Bob Ryan.
“An important part of my job,” says Ryan, “is
to make the forecast as clear and understandable as possible.” Whether he is forecasting a
blizzard, severe thunderstorms, or a sunny
spring day, “it comes down to hand-holding
with people because they are concerned. They
ask: ‘Can I go out? What should I wear?’” He
tries to give people as much information as possible. That helps them make good decisions.
Doppler radar tower
LESSON 4
In addition to radar and satellite information, Ryan also uses data from ground weather
instruments (for example, thermometers,
anemometers, and barometers). Even special
airplanes collect data that are mapped and fed
into computer models. The computer models
calculate wind, precipitation, temperature,
and weather movement at locations around
the globe. Ryan compares predictions calculated by several different models to see how
well they agree.
Ryan says that the science of weather forecasting is a lot like the science of medicine.
Medical doctors use all the available tests, Xrays, and other methods to diagnose a patient’s
condition. Meteorologists do the same thing to
arrive at a forecast, he says. They ask: “What are
the weather data and the calculations showing?
What does it mean to our local area?”
H E AT T R A N S F E R
AND THE
MOVEMENT
OF
AIR
reports the forecast for the first time on the
radio at 3:30 P.M. Then, with weather images
moving across a computerized map, he
explains the forecast to television viewers at
4:00, 5:00, 6:00, and 11:00 P.M.
Ryan gives his forecast in front of a green
board called a “chroma-key.” The computer
image of each map is electronically projected
onto any lime green space on the board. The
public sees Ryan in front of the computer
images, even though they are not really behind
him. Can you guess why he doesn’t wear lime
green?
Inspiring the Next Generation
Some years ago, Ryan decided he wanted to get
more young people excited about the weather.
He created a program called 4-WINDS to teach
students about weather. With the help of area
businesses, Ryan’s TV station donated weather
stations to local schools. Each weather station
contains instruments for measuring weather
variables (including temperature, pressure,
STC/MS™ C ATA S T R O P H I C E V E N T S
MATTHEW BAILEY/NSRC
Presenting the Weather
When Ryan presents the weather, he decides
what part of the local weather is most important to viewers. “Each situation
is a little bit different,” he says.
If thunderstorms are forming in
the mountains, he shows the
radar pattern. “If I’m following a
tropical system, like a hurricane, I might use almost hourly
satellite images,” he explains.
Ryan often links his weather
report to other news. For
instance, he once showed a
tropical storm forming over the
Pacific Ocean. He explained how
the storm’s rainfall could help
put out fires that were raging in
Mexico.
Once Ryan has an idea for
the forecast, he works with
another meteorologist to set up
weather images on a computer
system. At 3:20 P.M., Ryan puts
Bob Ryan working in the Channel 4 Storm Center
together the final forecast. He
51
H E AT T R A N S F E R
AND THE
MOVEMENT
OF
AIR
humidity, and wind)
and a computer to
store the data. In
2000, students from
200 schools participated in the project,
using their computers
to exchange weather
data on the Internet.
Ryan hopes that
young people who
are interested in the
weather will have a
better understanding
of science and maybe
even become meteorologists. They need
to have a strong
background in math
and science and do
well in those subjects, he says. Ryan
Bob Ryan gives his forecast in front of a green board called a “chroma-key.” The public
learned about weather
sees what is shown on the TV monitor in the upper left-hand corner.
by studying science in
college and earning a
master’s degree in physics and atmospheric
term forecasts, to studying global climate change,
science.
to managing water resources. Most of all,” he
“I think there’s a lot of opportunity for people
says, “it should be something you consider fun
interested in this field—from improving shortand look forward to doing.” Write a 3-4 sentence summary about what you just read. Connect these ideas to your lab!
52 STC/MS™ C ATA S T R O P H I C E V E N T S
MATTHEW BAILEY/NSRC
LESSON 4