Weather forecasts could become less accurate as the number of flights across the world continues to decrease due to the coronavirus pandemic.
Since the beginning of flight, aeroplanes have provided important information about the current state of the atmosphere.
The more accurately the current weather is known, the more accurate the forecast will be.
Fewer flights are taking off during the pandemic
Data reports from aircraft are combined with other information obtained from manned and automated weather stations, weather buoys, radar, radiosondes, wind profiles and satellites.
This gives a whole host of information about air pressure, temperature, wind, humidity, rainfall amounts and sunshine through the depth of the atmosphere.
The European Centre for Medium-Ranged Weather Forecasting (ECMWF) notes there has been a 65% reduction in the number of data reports, from about 50,400 per day on 3 March to under 18,000 on 23 March.
With EasyJet today announcing it will ground its entire fleet of planes for at least two months, this reduction is likely to continue over the coming months – potentially into the summer – and this could well have an impact on weather forecasts.
With less data reports being made, the accuracy of our weather forecasting could be affected.
In 2019, the ECMWF investigated the impact on forecasts if aircraft reports were not used, and they found a large impact at the typical cruising altitude of flights.
At this height, the short-range wind and temperature forecasts deteriorated by up to 15%.
However, there was also a smaller impact near ground level, with a reduction in accuracy of the surface pressure of up to 3%.
Flights virtually empty across the world
Fortunately, in January this year, extra satellite information was incorporated into forecasts, which could make up for some of this loss of accuracy.
Wind data collected from the European Space Agency’s Aeolus satellite has been shown to significantly improve weather forecasts, and the ECMWF started to use this information on 9 January this year.
Despite this, it is still possible that as the number of flight reports continues to diminish, there may be some reduction in the accuracy of forecasts over the coming months.
It seems even the weather forecast isn’t immune to COVID-19.