Space weather refers to dynamic and often unpredictable variations in the near-Earth space environment caused by solar activity, including solar flares, coronal mass ejections (CMEs), and solar energetic particles (SEPs). These phenomena trigger cascading disturbances such as radio blackouts, solar radiation storms, and geomagnetic storms, that can severely impair the technological infrastructure underpinning modern society, including power grids, satellites, communication networks, navigation systems, and even human health1. This commentary focuses on the impacts of space weather on aviation. As shown in Fig. 1, the stakes for aviation are especially high: disruptions to high-frequency communication compromise transoceanic connectivity; satellite navigation errors undermine route precision; degraded surveillance limits situational awareness; and elevated radiation exposure poses health risks to crews and passengers. Beyond immediate safety concerns, such impacts also reverberate through the economic and environmental dimensions of aviation, contributing to inefficiencies, delays, and excessive emissions.

Fig. 1: Mechanisms of space weather impact on aviation.
figure 1

Disruptions affect communication, navigation, surveillance, and radiation exposure, with direct consequences for flight safety and efficiency.

HF communication blackouts

While very high frequency (VHF) radio remains the backbone of routine aircraft communication, high frequency (HF) radio is indispensable on transpolar routes where geostationary satellite coverage is limited or unavailable. However, HF links are highly susceptible to space weather disturbances. SEP events can trigger polar cap absorption (PCA), producing ionospheric conditions that severely attenuate or even block HF signals for several hours. Such blackouts compromise the safety margin of polar operations, forcing airlines to reroute flights to lower latitude areas. These reroutings come at a considerable cost, additional fuel burn, reduced cargo capacity due to higher contingency fuel requirements, extended flight times, and increased crew expenses. A striking example occurred during the 2003 Halloween Storms, when multiple New York-Hong Kong flights were diverted, consuming an extra 26,600 pounds of fuel and losing more than 16,500 pounds in payload2. Recent modeling studies indicate that even a single day of HF communication outage could generate direct operational losses of several million euros for airlines regularly flying polar routes3. Beyond economic implications, such disruptions also create significant challenges for air traffic controllers, who must coordinate rerouted flights under conditions of degraded communication capacity, amplifying workload and compounding safety risks.

Satellite navigation failure

Satellite navigation has transformed aviation by enabling performance-based navigation, continuous descent operations, and flexible trajectory design, thereby improving efficiency and reducing emissions4. Yet this reliance on space-based signals introduces vulnerabilities. Space weather events can degrade or interrupt signals from Global Navigation Satellite Systems (GNSS), with even brief disruptions compromising the integrity required for precision operations. For example, during the Halloween storms of October 2003, ionospheric disturbances severely degraded GNSS performance across North America and Europe. Aircraft approaching major airports experienced loss of vertical navigation guidance for satellite-based approaches for over 10 h5, forcing pilots to rely on conventional ground-based aids. Such reversion increases separation minima, reduces available airspace capacity, and undermines decades of progress toward route optimization. These incidents highlight how a single extreme space weather event can erode the safety and efficiency benefits of advanced satellite navigation.

Surveillance system disruption

Automatic Dependent Surveillance-Broadcast (ADS-B) has transformed modern aviation by enabling continuous, highly accurate aircraft tracking and enhancing situational awareness for both pilots and air traffic controllers. However, its dependence on satellite-based navigation signals represents a critical vulnerability to space weather disturbances6. In addition, severe solar radio bursts can directly disrupt radar surveillance infrastructure, as evidenced by the 2015 event that temporarily disabled radar systems across Sweden, Norway, and Belgium7. Such outages stress the fragility of surveillance networks during extreme space weather. When real-time surveillance is lost, air traffic controllers must revert to procedural separation standards, which significantly reduces airspace capacity and leads to cascading operational delays. This shift not only increases controller workload and cognitive stress but also forces the system to function much closer to its safety margins, amplifying the likelihood of human error and compounding risks across interconnected air traffic networks.

Aviation radiation exposure

Aviation radiation exposure is a well-recognized occupational hazard for flight crews, prompting regulatory agencies to establish radiation dose limits to safeguard both aviation personnel and the traveling public. During SEP events, radiation levels can increase dramatically, particularly along high-latitude polar routes and on long-haul intercontinental flights, where exposure times are extended. To mitigate these risks, airlines may implement strategies such as reducing flight altitude, adjusting flight paths, or delaying departures. While such measures can significantly decrease radiation doses, they come with operational trade-offs, including an obvious increase in fuel consumption and flight time extensions. Taking the 2003 Halloween Storms as an example, these constraints may compel airlines to cancel flights entirely, leading to direct economic losses that can reach tens of millions of euros per incident8. Besides, the rise of autonomous aviation adds a new layer of vulnerability, as single-event effects from cosmic radiation can disrupt critical electronics onboard. This expands risk assessment beyond human health to include technological resilience, emphasizing the need for integrated mitigation strategies spanning operational, economic, and engineering domains.

Implications for clean and resilient aviation

The intersection of space weather and aviation underscores a fundamental tension in the pursuit of sustainable air transport. On one hand, performance-based navigation, advanced surveillance, and other technological innovations enable more fuel-efficient operations, reducing emissions and supporting greener aviation. On the other hand, these efficiencies inherently increase reliance on satellite-based and electronic systems that are vulnerable to space weather. Importantly, solar activity follows an approximately eleven-year cycle, meaning the intensity and frequency of space weather events vary predictably over time, yet can still pose sudden and severe threats. With the increase in global air traffic, ensuring the resilience of aviation to space weather is not merely a niche concern but a prerequisite for safe, reliable, and sustainable growth. Addressing this challenge requires the following tasks.

Enhanced forecasting capability

Advancing space weather prediction on aviation-relevant timescales of minutes to hours is essential to move from reactive to proactive risk management. Current global models often provide general warnings but lack the resolution and timeliness required for aviation. By integrating real-time satellite observations, ground-based ionospheric sensors, and machine-learning techniques, forecasts can be tailored to specific flight corridors and altitudes. A prime example is the Chinese Meridian Project (CMP), a nationwide chain of ground-based observatories monitoring the ionosphere, magnetosphere, and upper atmosphere in real time9. Data from CMP and similar initiatives provide high-fidelity inputs that can significantly enhance forecasting accuracy, supporting targeted warnings for vulnerable polar and equatorial routes. In the long term, predictive accuracy must approach the reliability of meteorological forecasts to achieve true operational resilience.

Seamless integration into operations

Forecasts alone are insufficient unless they are embedded into decision-making workflows for pilots, controllers, and airline dispatchers. Space weather intelligence should be integrated into air traffic management systems much like turbulence or convective weather data, providing actionable recommendations rather than raw indices. This could include real-time rerouting to avoid polar regions during HF blackouts, altitude adjustments to mitigate radiation exposure, or dynamic spacing protocols when GNSS precision is degraded. Seamless integration would require standardized interfaces, clear communication protocols, and automated alerts to reduce workload and avoid misinterpretation under time pressure. The ultimate goal is to ensure that space weather becomes an operational variable considered as routinely as meteorology.

Holistic optimization approaches

Responding to space weather cannot focus on safety alone but must balance multiple, sometimes competing objectives. Advanced decision-support frameworks should integrate safety, operational efficiency, and environmental performance to ensure that resilience measures do not inadvertently increase fuel consumption or emissions10. For example, rerouting around polar regions may mitigate HF communication risks but could significantly increase CO2 output if not optimized alongside sustainability goals. Multi-objective optimization tools, using big data and AI, can help identify solutions that minimize trade-offs while maintaining regulatory compliance. Such frameworks will be crucial for the next generation of sustainable aviation systems, where resilience and climate responsibility must advance hand in hand.

Global coordination and policy frameworks

Because space weather disturbances transcend national borders, no single state or airline can manage the risks in isolation. Harmonized international standards, supported by International Civil Aviation Organization (ICAO) and regional aviation authorities, are necessary to ensure consistent procedures for communication, navigation, and surveillance during disruptions. Effective resilience will also depend on global data sharing between space agencies, meteorological services, and aviation stakeholders, enabling the fusion of diverse monitoring systems into a coherent picture. Projects like the CMP, alongside U.S., European, and Japanese monitoring networks, exemplify how national infrastructures can contribute to a globally integrated observing system. Policy frameworks must also include training, contingency planning, and international exercises that build collective readiness. In the face of growing solar activity, collaborative governance will be as important as technological innovation.

Looking ahead

Space weather poses systemic risks to aviation on par with volcanic ash clouds or severe meteorological phenomena, yet the industry preparedness and institutional response remain comparatively underdeveloped. Unlike turbulence or storms, which are routinely integrated into flight planning and operational protocols, solar-driven disturbances often remain at the periphery of decision-making despite their potential to disrupt satellite navigation, communications, surveillance systems, and increase aviation radiation exposure. Elevating space weather to the same level of operational significance is therefore critical, not only for safeguarding flight safety and protecting passengers, crews, and assets, but also for preserving the environmental and efficiency gains promised by advanced navigation and routing technologies. By embedding resilience into both technical systems and regulatory frameworks, the aviation sector can ensure that the clean technologies shaping the future of air transport remain dependable even under the most extreme conditions our star may produce.