Covid-19 flight cuts make weather forecasts less accurate

Since the start of the pandemic, the number of aeronautical meteorological observations has decreased by 50-75%. The quality of forecasts has declined, but at the same time their importance has increased. Lack of weather data can seriously affect the economy.

During passenger flights, aircraft record data on air temperature, relative humidity, pressure, and wind, which helps forecasts to be more accurate. The cancellation of a large number of flights makes this kind of observation almost impossible. Despite the decrease in the amount of data, the impact of meteorological reports has become stronger, so they are designed for a longer time than before, said a group of scientists from the Lancaster Environmental Center in the UK. Details of the study are published in the AGU journal.

The accuracy of weather forecasts can affect the stability of the economy and agriculture, as well as affect the energy sector. “If the uncertainty in the forecasts exceeds the threshold, it will lead to unstable voltage in the electrical network,” said Ying Chen, a senior fellow at the center and lead author of the study. “It could lead to a power outage, and I think this is the last thing we want to see during a pandemic.”

The team compared data from March-May 2020 with those from 2017, 2018, and 2019 and found that information on temperature, relative humidity, wind speed, and the pressure was not as accurate. This is despite the fact that in February before the flights were canceled, forecasts were better than in previous years. The authors also noticed that the forecasts for surface pressure and wind speed remained the same in the short term (one to three days) but worsened for the long term (four to eight days).

In addition, precipitation data around the world did not change significantly, as they were based on satellite observations. But March, April, and May have been relatively dry this year in most countries, scientists say – and warn rainfall forecasts could be hit during hurricane and monsoon seasons.

The remote (Greenland, Siberia, Antarctic, and the Sahara Desert) and busy areas of air travel (North America, South-East China, and Australia) are particularly affected. The accuracy of forecasts in Western Europe has not changed much, although the number of aircraft over the region decreased by 80-90%. Perhaps this is due to the dense network of ground-based meteorological stations and balloon measurements, which compensate for the shortage of aircraft.

The authors suggest that there may be more and more sources of meteorological data, especially in areas where little data is collected and those that rely heavily on commercial flights. This will help mitigate the impact of these types of global emergencies in the future.