The WMO Global Observing System is the foundation for weather and climate services in 193 WMO member states and territories. However, these meteorological measurements rely on instruments onboard commercial aircraft to collect and transfer data to ground stations.
The drastic decline in flights following the global coronavirus outbreak has caused meteorological measurements to fall from 75% to 90%. For meteorologists this shock to the system means weather forecasts will lack accuracy as only a fraction of 800,000 daily readings are available. To compensate for this loss, countries will have to rely on their own national weather forecasting capacities, which will be of particular importance during the Atlantic hurricane season.
Normally, data collected from air travel increases the accuracy of weather forecasts by 10% with nearly 250 million weather observations collected each year and fed into computer models for national weather services. Due to the lack of data, surface-based weather observations are in decline worldwide, particularly in Africa and Latin America.
Airlines also depend on these meteorological measurements to determine the strength of the jet stream and identify conditions that can cause icing. In the same way, airlines use these measurements in real time to make operational decisions to mitigate turbulence through the Turbulence Aware programme by the International Air Transport Association.
In the short and long-term future, meteorological observations that depend on data collected from airlines will continue to lack accuracy until the airline industry can recover from the impact of Covid-19 and return to pre-coronavirus levels.