Background
The Norwegian Safety Investigation Authority (NSIA) conducted a thematic investigation to determine whether climate change has affected aviation operations in Northern Norway during winter. Flying in this region during winter is inherently demanding due to variable and often challenging weather conditions, further influenced by local geography and topography at airports.
Incidents on 12 February 2023
On Sunday, 12 February 2023, demanding weather conditions posed significant challenges for air traffic at Tromsø Airport, Langnes. All major airlines—SAS, Widerøe, and Norwegian—reported incidents related to heavy precipitation and strong winds on flights to or from the airport. A SAS aircraft encountered difficulties during takeoff due to strong crosswinds and a slippery runway, veering off the edge of the runway before stopping. Three Widerøe aircraft were struck by lightning and reported severe icing during approach. A Norwegian aircraft was struck by lightning and received a wind shear warning just before landing. Another SAS aircraft received a wind shear warning during approach, aborted the landing, and during the subsequent go-around encountered severe icing that caused strong vibrations in one engine.
Meteorological Analysis
The NSIA commissioned the Norwegian Meteorological Institute (MET) to prepare a comprehensive report analyzing weather trends in Northern Norway and Svalbard. The analysis showed that challenging winter weather conditions for aviation are largely driven by the location and intensity of large-scale synoptic low-pressure systems. Since 1991, the trend has been for a higher number of low-pressure systems to follow a more southerly zonal track, but most continue into the Norwegian Sea and Barents Sea. No general historical trend from 1991 to 2023 indicated a deterioration of winter weather conditions for aviation in Northern Norway and Svalbard. Similarly, no general trend towards higher frequency or deterioration was observed for the future. However, substantial year-to-year variation in the frequency and severity of weather impacts was documented, expected to remain significant and dominate any moderate trends. Estimates of future changes carry uncertainty due to the complexity of how weather phenomena may change.
Learning Points and Recommendations
The investigation identified several learning points, including the benefit of using high-resolution models to anticipate weather situations known to create challenging aviation weather. Understanding of local weather conditions at several airports in Northern Norway was increased, and a potential change in aviation weather conditions in Southern Norway was identified. The NSIA issued safety recommendations to improve aviation safety by increasing knowledge and providing more accurate weather forecasting.