PHOENIX — With more and more airlines grounding their planes due to the coronavirus pandemic, weather forecasts may take an unfortunate hit.
Why is that?
Fewer planes flying means less observations gathered, which go into computer models that help with forecasting.
Many people may not realize it, but commercial and cargo airplanes are constantly gathering and sending back data, such as temperature, pressure, wind speed and direction, while they're flying. It's similar to how National Weather Service meteorologists gather upper-air data via weather balloons, but on a much larger and more frequent scale.
With a significant slowdown in airline travel, agencies like the National Oceanic and Atmospheric Administration, or NOAA, and the European Center for Medium-Range Weather Forecasting, or ECMWF, are keeping a close eye on how this could impact forecasts.
In a statement, ECMWF says that there was a 65% reduction in aircraft reports on March 23 compared to March 3. They expect those numbers to continue to go down in the coming days and weeks, which will impact forecast quality in the short range.
Number of aircraft reports received and used by ECMWF per day
Source: ECMWF
One of the aircraft-based observations used frequently is called Aircraft Meteorological Data Relay, or AMDAR, and officials at ECMWF say that AMDAR coverage in Europe could be reduced by 65% or more in the coming month and continue into summer.
NOAA is also expecting a substantial reduction in availability of AMDAR data in the United States.
Aircraft Meteorological Data Relay (AMDAR) data used by NOAA from late February through late March
Source: NOAA
However, while a decrease in this data will likely impact forecast model skill, Susan Buchanan with NOAA says that it doesn't necessarily translate into a reduction in forecast accuracy.
"It's too soon to quantify the exact impact because the decrease is only occurring for certain flights and routes," Buchanan wrote in a statement. "National Weather Service meteorologists use an entire suite of observations and guidance to produce an actual forecast."
To read ECMWF's full statement, CLICK HERE.