Navy vessels depend on accurate weather information to safely traverse
oceans to reach battle zones. The timing and nature of strike operations
from the sea must also be in sync with weather conditions.
Technologies that can predict weather conditions with a high degree
of precision are valued tools for U.S. military commanders as they
prepare for war.
The Navy’s involvement in predicting weather for all U.S.
military forces is integral to the Defense Department’s war
planning work, because awareness of weather conditions is necessary
to fight today’s wars, said Richard Spinrad, technical director
for the Oceanographer of the Navy.
“Fighting without a knowledge of the weather is like fighting
with no maps of the terrain,” said Cmdr. David Titley, a Navy
meteorologist assigned to the office of the assistant secretary
of the Navy for research, development and acquisition.
“The side that can best anticipate and exploit changes in
the weather creates a significant advantage for itself,” said
Paul Schneider, principal deputy assistant secretary of the Navy
for research, development and acquisition. “As it has been
said many times before, we are not interested in a fair fight. We
seek all possible advantages for our combat troops,” he said.
The Fleet Numerical Meteorology and Oceanography Center (FNMOC),
based in Monterey, Calif., and the office of the oceanographer,
based at the Naval Observatory in Washington, D.C., work in tandem
to forecast weather for the fleet. While FNMOC’s 300 employees
engage in “operational processing,” collecting weather
data from sources all over the world and plugging the data into
models, the oceanographer’s office manipulates the information
to find patterns, maintains historical records and develops program
initiatives. The oceanographer’s office is the program sponsor
for FNMOC, as well as for the Naval Meteorological and Oceanographic
Command (METOC) in Bay St. Louis, Miss.
FNMOC processes weather information by using sophisticated modular
supercomputers. Because they are modular, the entire system does
not go down when one module breaks. The computer has the capacity
to work around a broken module until it can be replaced. Much of
the data collected from the supercomputers also is sent simultaneously
to another of FNMOC’s customers, the Commerce Department’s
National Weather Service, which provides weather information to
the public. FNMOC also hosts an unclassified free Web site, accessible
through http://www.fnmoc.navy.mil. According to Spinrad, the Navy’s
increasing Web presence is part of the concept of a “net-centric
Navy.”
“Weather models have been deemed a strategic national asset
by the federal government,” said Bob Bishop, chairman and
chief executive officer of SGI Federal, the company that makes the
modular supercomputers used by the Navy to collect weather data.
“Weather affects everyone,” he said. “The travel,
aviation, sports, recreation and military industries” all
have business to conduct that is either successful or not, depending
on the nature of the weather, said Bishop. In fact, Bishop reported,
earlier this year, the Navy and another of SGI Federal’s customers,
The Weather Channel, signed a memorandum of understanding to engage
in professional collaboration. The Weather Channel is reportedly
interested in generating the same kinds of weather models created
by FNMOC, which “utilize the largest existing, real-time databases
of oceanic and atmospheric operations,” Bishop said.
Weather models fill in the gaps of time and space, said Titley.
“We need to be able to put the data that we collect together
into a coherent package, and the way we do that is to use the model
to step forward in time and space and forecast the weather.
“So I can go to any point (on the weather model), be it the
Persian Gulf, the central Pacific or New York City, and I can tell
what the forecast will be,” said Titley.
The supercomputers are located at FNMOC headquarters, in Monterey.
“We receive data from sources all around the world. From ships,
satellites, buoys, aircraft and land stations, we are continually
receiving data, and we assimilate that data into our models,”
said Mike Clancy, chief scientist and deputy director of FNMOC.
Eight Navy military survey vessels, one P-3 aircraft, several mobile
survey teams, unmanned aerial vehicles and unmanned underwater vehicles
are used to collect the data. Also, cooperative agreements with
other countries allow the Navy to glean additional information,
said Spinrad.
Two models are run by the supercomputers that are available to
the fleet at all times. A global model, which provides up-to-the-minute
reports of weather conditions anywhere on the face of the earth,
is called the Navy Operational Global Atmospheric Prediction System
(NOGAPS). The Coupled Ocean/Atmosphere Mesoscale Prediction System
(COAMPS) is a regional model that covers selected parts of the world
and can be run at a higher spatial resolution to provide a more
detailed prediction of the weather. “We focus the COAMPS model
runs in areas of high Defense Department interest, which are often
coastal areas,” said Clancy.
“This reflects the fact that the Navy in the post-Cold War
world, has many of its operations in coastal areas, whereas during
the Cold War, the main Navy mission was to take on the Soviet fleet
in the open ocean,” Clancy explained.
Sailors are able to access weather conditions by logging on to
the oceanographer’s Web site or the master environmental library,
a military-only site managed by the oceanographer’s office.
They also can request specific regional information from the oceanographer’s
staff. Also, when a vessel enters a particular region, the oceanographer’s
office tracks its progress, and alerts shipboard personnel if any
weather conditions could affect its course, according to Ed Weitzner,
manager of modeling and simulation environmental support policy
for the oceanographer.
Weather’s Effects on Weapons
Part of Schneider’s duties as deputy assistant secretary of
the Navy for research, development and acquisition is to recommend
which tools must be acquired to maintain and improve the Navy’s
forecasting capabilities. “We are sensitive to the effects
that clouds, high winds, rain, snow and cold temperatures have on
both weapons and the personnel who function in those environments,”
he said.
According to Spinrad, “we have the capability to forecast
high-resolution images of winds and precipitation,” he said.
This is a critical capability for planning air strikes. For example,
“the modern battlefield is very much dominated by precision-guided
munitions, such as laser-guided weapons. Lasers are sensitive to
things like clouds and aerosols, like smoke and dust,” Clancy
said.
“In the case of cruise missiles, if they’re encountering
a severe headwind, they might not be able to make it to the target.
Or a high temperature might also make it difficult to reach the
target,” he said. The wind also affects the safety of such
operations as in-flight refueling, and knowing what the weather
conditions will be helps officials to determine whether to schedule
aircraft sorties, Clancy said.
For example, Clancy explained, the D-day invasion of Normandy,
during World War II, was planned for a particular day, partially
because of optimal weather conditions. “Weather was a significant
issue, as well as the size of the ocean waves. The weather was a
big factor in the go/no-go decision-making process to launch the
attack that day,” he said. The failed Iranian hostage-rescue
mission during the Carter administration, Clancy related, was complicated
by “a severe sandstorm impeding helicopter operations,”
he said.
More recently, during the Gulf War, “the weather over the
target was clearly an issue, particularly the amount of cloud cover,
and there were lots of instances where aircraft were not able to
use their precision-guided weapons because of restricted visibility,”
Clancy said. “One might decide not to launch a strike on a
particular day because the ceiling (cloud cover) could be too low,”
he said.
The Defense Department has a long history of trying to understand
and predict the weather and the conditions of the ocean. “We
want to be able to pick the weather to fight in,” said Clancy.
However, the ability to predict the weather is not foolproof, according
to Titley. “The chaos in the atmosphere limits the capability
of predicting everything. But from a military perspective, if I
could tell a commander what the weather would be like for the next
12-15 days, that would influence not only the specific tactics that
he would take, but would also impact the operation as a whole. If
I knew I had a ‘weather window’ of opportunity, that
could potentially impact when the commander would conduct an operation,”
Titley said.
There is a certain amount of human guessing that must be used to
determine that weather window, to fill in the gaps of the models.
“A model by definition, does not incorporate every scale that’s
in the real atmosphere,” Titley said. “It’s pretty
good, but like any model, there are some assumptions and simplifications
that have to be made. That’s one of the reasons we have people
employed as meteorologists, because if the models were perfect,
we wouldn’t need them.”
The weather affects the jet stream of the ocean, and knowledge
about specific conditions involving the water and the ocean floor
can affect the performance of shipboard electronics, said Weitzner.
“There are highs and lows in the atmosphere of the oceans,
and conditions such as twirling water can create phenomena such
as a slow-moving cyclone. Transmission ability can become limited
if this creates a muddy ocean bottom,” he said. However, “currents
can also act as an effective acoustic block, so if you know where
the front of the weather current is, you can hide behind it and
not be detected (by an enemy),” he said.
The undersea sounds can sometimes be loud, and this can influence
ships’ sensors such as sonar. “If the ocean is noisy,
it’s like you are in a shower, and you can’t hear anything
outside the shower.” Whether the ocean bottom is muddy also
can affect the noise levels inside the ocean. “Sounds can
bounce off the bottom,” but if the bottom is muddy, noise
is simply absorbed, Weitzner said.
Titley explained that since there are so many factors that go into
predicting the weather, it is impossible to forecast with 100 percent
success. “The weather keeps changing, and that’s why
we have to keep paying attention to it,” he said.