The advance of global warming It's not just noticeable at ground level. The variations in the upper atmosphere caused by the increase in carbon dioxide (CO2) This could result in more unstable signals for radio and for some communications that pass through the ionosphere.
An investigation led by the Kyushu University It points to a counterintuitive effect: while CO2 heats up on the surface, in the ionosphere It cools. This cooling modifies the air density and wind circulation at about 100 kilometers altitude, a combination that promotes plasma irregularities capable of disrupting space and radio communications.
What the study found
The team used a full atmosphere model to compare two scenarios: 315 ppm of CO2 (historical reference) vs. 667 ppm (high emissions projection). For reference, the average recorded in 2024 was around 422,8 ppm, according to recent series.
The researchers focused on the vertical ion convergence (VIC), a key process in the formation of the sporadic layer E. With higher concentrations of CO2, the model showed a global increase of the VIC between 100 and 120 km, a decrease in the points of maximum activity of about 5 km and changes in the diurnal patterns of occurrence.
The simulations attribute these variations to the lower atmospheric density alterations in wind circulation resulting from ionospheric cooling have already been observed. These results, published in Geophysical Research Letters, offer one of the first pieces of evidence of how the climate change can affect small-scale plasma phenomena.
What is the Es layer and why does it matter?
The so-called sporadic E layer (Es) It is a dense accumulation of metal ions that appears irregularly between the 90 and 120 km altitudeIts intermittent nature makes it difficult to predict, but when it forms it can interfere with high frequency (HF) and very high frequency (VHF) communications.
According to the study, with high levels of CO2, Es tend to intensify, to manifest themselves to lower altitude and persist throughout the nightThis situation increases the likelihood of distortions and interruptions in links that depend on reflections or traverses through the ionosphere.
Potential impact on radio and satellite operations
Ionospheric disturbances can result in episodes of fading, delay, and path changes of the signals. This affects services that require stable propagation.
- Aviation and air traffic control: long-range HF links and backup communications on ocean routes.
- Maritime navigation: VHF communications and safety and rescue networks.
- Broadcasting and critical services: possible interferences in HF/VHF and in emergency operations.
- Nearby spatial environment: changes in the high density of the atmosphere that affect orbits and lifespan of satellites already the evolution of space debris.
In addition, plasma irregularities can cause noisier signals in certain scenarios, posing an additional challenge for systems that traverse the ionosphere.
Keys for Spain and Europe
In the European context, greater intermittency of the Es layers would have implications for telecommunications, air traffic management and maritime services. Spain, due to its position between the Atlantic and the Mediterranean and the importance of peninsular and canary airspaceIt benefited from strengthening ionospheric monitoring linked to security communications.
For operators, control centers, and research networks, having access to operational forecasts of the ionosphere, technological redundancies (alternative bands and backup routes) and switching protocols that minimize temporary service degradation.
Mitigation and preparedness measures
Long-term planning can integrate ionospheric sensor networks, data assimilation models and early warning tools that report on windows of higher risk for spread.
- Continuous monitoring: ionospheric soundings and GNSS observations to detect irregularities.
- Resilient design: antennas and receivers with interference mitigation and strategies for alternative frequencies.
- Institutional coordination: collaboration between space, aviation and maritime agencies for joint protocols.
The goal is reduce exposure to episodes of degradation and maintain continuity of service when the ionosphere becomes more variable.
Climate context: data that helps to understand change
According to NASACO2 is a greenhouse gas that retains heat and whose atmospheric concentration has increased by around 50% in less than two centuries, mainly due to the use of fossil fuels.
That CO2 comes from the extraction and combustion of coal, oil and gas, in addition to forest fires and natural sources such as volcanic eruptions. The seasonal cycles of the photosynthesis They modulate their level year by year.
What Kyushu's work highlights is that the climate change It doesn't stay on the surface: reaches the upper atmosphere and modifies physical conditions that support modern communications.
The body of evidence suggests that, as CO2 concentrations increase, ionospheric variability will increase linked to the Es layers, with possible effects on radio, critical links and satellite management; a scenario that calls for scientific monitoring and technical preparation in Spain and throughout Europe.
