Page 33 - World Airnews Magazine July Edition 2020

FEATURE FEATURE

LOSS OF AIRCRAFT DATA Arizona have been transformed into parking Airlines, is scheduling more flights relative to may be airlines themselves, since forecasts

of upper level winds are used to calculate
some of the other major U.S. airlines.
lots for billions of dollars worth of jets.

In addition, about 130 of the more than
UN AGENCY SOUNDS ALARM AS NOAA 3,500 commercial planes in the domestic fuel needed, flight routes and times.
But upper level data is also crucial for

TAKING A TOLL ON WEATHER TALLIES MISSING OBSERVATIONS network have a special moisture sensor as forecasting the evolution of weather sys-

Meteorologists know that the aircraft data
makes a measurable impact on forecast well as wind and temperature measuring tems, he said.
equipment, Marshall said. Luckily for the
“I think it’s fair to say that covid-related
FORECASTING skill, but they’re not sure how big of a NWS, those sensors are on Southwest and reductions might cause a noticeable reduc-

hit forecasts are taking right now. This

UPS aircraft, most of which are still flying.

tion in the forecast quality, but it gets really

uncertainty is potentially problematic, “That moisture data is very valuable for difficult to really pin it down,” Ingleby said.

considering what is expected to be a the models, particularly as we approach “We don’t want to say there is no impact,

busier-than-average Atlantic hurricane severe weather episodes,” Marshall said. but we don’t want to say there’s a great big
season. impact and any bad forecast is due to it,”

The World Meteorological Organization TESTING THE IMPACTS OF MISSING Ingleby said.
(WMO), a United Nations agency, issued DATA IS IMPOSSIBLE NOAA says it’s not seeing a clear trend in

a statement May 7 expressing concern Aircraft provide forecasters with the advan- the data that jumps out and corresponds to

about coronavirus-related deteriorations in tage of travelling at all times and gathering the loss of AMDAR data.

aircraft-based and ground-based weath- unique profiles of the atmosphere as “At this time, there is no clear signal/

er observations. The WMO found that, they change altitude over areas that may

globally, measurements from aircraft have not have been closely studied by other trend in the skill of the numerical guidance
fallen by an average of 75 to 80 percent observing platforms. Such areas include the the models are producing, and determining

any such impact of the lost aircraft data on

compared to average, “but with very large jet stream level above the Pacific Ocean model skill requires a rigorous and substan-

regional variations.” and the data-sparse region between Africa tial scientific analysis,” said Brian Gross,

For example, in the Southern Hemi- and Australia, along with the area above who leads NOAA’s Environmental Model-
sphere, the data loss is “closer to 90 per- the North Atlantic. ling Centre, which runs and tracks the skill

cent,” the WMO stated. According to the ECMWF, aircraft reports of the agency’s computer models.

According to the WMO, when operating at come in second, behind satellite data, In addition, NOAA’s Vaccaro cautioned

full capacity, the global aircraft-based observ- in terms of their influence on forecast that degradations in model skill don’t nec-

ing system produces over 800,000 weather accuracy. In early March, as European essarily translate directly into less accurate

observations per day using planes from 43 countries began enforcing their shutdowns, weather forecasts. “Even if a decrease in
airlines and several thousand aircraft. aircraft-generated weather reports across aircraft observation data impacts forecast

In the United States, as of April 20, “the Europe declined by 65 percent. There was model skill, it does not necessarily translate
daily output of meteorological data from also a 42 percent global decline in such into a reduction in forecast accuracy since

U.S. commercial aircraft has decreased to reports during the same period. National Weather Service meteorologists

approximately one quarter of normal lev- The ECMWF has investigated the impacts use an entire suite of observations and guid-

els,” according to NOAA spokesman Chris that removing aircraft data has on its forecast ance to produce an actual forecast,” he said.

Vaccaro. When at full capacity, aircraft model simulations and found that there is Ingleby and Marshall said it’s impossible

soundings, as such data is known, dwarf a particularly large effect at the jet stream to pinpoint how significant the impact of

the volume of the twice-a-day weather bal- level, between about 30,000 and 40,000 feet, missing data actually is, since one would

loons launched from 900 weather stations where planes typically cruise during flight. have to run an experiment that involves
around the world. Bruce Ingleby, a senior scientist at ECM- models deprived of aviation data alongside

In a typical year in the United States, WF, said the loss of all aircraft data from a control group, which would have a com-

COMMERCIAL AIRCRAFT ARE A Service’s Global Forecast System, or GFS more than 3,500 commercial aircraft pro- the European model would decrease the plete set of data for the same time period.

FORECASTER’S SECRET WEAPON model, and the world-leading European vide more than 250 million observations accuracy of a 12-hour forecast of winds Right now, such an experiment is impossi-

ecently , computer models For years, thousands of airliners and cargo model, run by the European Centre for Me- per year, according to a NOAA statement. and temperatures at the jet stream level ble, since data is in fact missing.

Rprojected that southern Florida planes have been involved in a side gig that dium Range Weather Forecasts (ECMWF) in (Not every aircraft in the sky is part of the by about 10 percent, with a statistically To help combat the data loss, agencies are

would see a deluge of several inches few passengers or package shippers have Reading, England. observing network). significant degradation of 3 percent when it enlisting help from an airborne observing

of rain. Such abundant rainfall would been privy to: gathering and transmitting At the global level, networks that vacuum Curtis Marshall, who manages the comes to surface pressure forecasts going network that a private company, FLYHT, op-
out to three to four days later.

have been a sharp departure from the weather data that’s then used for improv- up data from planes flying in Europe, Asia program, known as aircraft meteorological erates. They’re also ordering more frequent
Ingleby said that, ironically, those who

unusual heat and dry conditions that ing weather forecasts issued worldwide. and South America have helped to ensure data relay, or AMDAR, for the Weather might suffer the most from the missing data weather balloon launches in particular
Service, said right now, only about 1,000

have gripped that part of the state so far To gather crucial information for operat- an ever-growing flow of data that’s benefit- aircraft are sending the areas.

this year. ing the plane itself, such as determining its ed modelling centres worldwide, boosting agency weather data each As for forecast situ-

In the end, though, Miami ended up airspeed and motion relative to the ground, model skill and forecast accuracy. day, given coronavirus-re- ations like Miami’s this

seeing just 0.26 inches of rain, and the instruments on an airplane’s nose - they However, with the paucity of flights in lated flight reductions. past weekend, the stan-

medium as well as shorter-term model resemble pointy, metal needles sticking out the air now, the pandemic has disrupted “Our number of daily air- dard weather forecast

projections turned out to be a complete of the fuselage, pointed forward, into the that data flow, turning it from a fire hose craft profiles is fluctuating disclaimer applies more

bust. A forecast miss of such a magnitude airstream - measure the characteristics of to more of a trickle. Meteorologists don’t between 20-30 percent of than usual: All forecasts

is relatively unusual, and it prompted the air mass around them. know exactly how much of an impact that’s normal, depending on the contain an element of

some meteorologists to wonder whether This includes the wind direction and having on forecast skill. day of the week,” he said. uncertainty to them, per-
missing data because of the coronavirus speed, air pressure, temperature and, in In the United States alone, airlines are Marshall said European haps more so now than at

pandemic might be to blame. Normally some cases, humidity as well. operating skeletal schedules and have nations have seen a greater other times. Q

gathered by commercial aircraft, much of Government programs run in the United opted to store much of their fleets rather reduction in observations,

the data has stopped flowing since many States, such as the efforts of the National than continuing to lose money by flying in part because the U.S. net- Article courtesy of

flights have been cancelled. Oceanic and Atmospheric Administration, near-empty planes. According to the trade work involves cargo carriers https://www.

The answer, experts say, is that it’s along with international agencies and private group Airlines for America, U.S. airlines that have not cut back on washingtonpost.com/
unlikely that certain missing data was companies have tapped into some of this idled 3,162 planes, which accounts or 51 their operations. Also, the weather/2020/05/12/

the cause, but it’s also unlikely that the data to pipe it into computer models that percent of their fleet, as of May 10. network’s largest domestic weather-forecasting-

data shortfall is not having some negative help meteorologists forecast the weather. Airports such as Tulsa International, contributor, Southwest coronavirus-flights/

effect on forecasts. This includes the National Weather Kansas City International and Pinal Airpark in

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