When the clouds covered the climate narratives: Time machine…

Turning the clock back to the late 1990s and early 2000s, the scientific community was faced with one of the most fascinating, yet powerful ideas in modern astrophysics: the theory that Earth's climate is not shaped exclusively by terrestrial factors, but is also influenced by the distant universe.

The Geopolitical Void of the Cold War

To understand the tension of that era, we must look beyond the laboratories. The end of the Cold War had left international diplomacy and large industrial complexes without the traditional, existential threat that justified gigantic state funding.

The anthropogenic model

The carbon model came to fill this gap, offering a new, global convergence target. A whole new market was built around reducing emissions : green technologies, emissions trading and alternative energy sources. Within this context, the assumption that the climate is controlled by humans proved extremely useful. In contrast, a theory that attributed climate change to the Sun or the Milky Way could not be taxed, legislated or fueled new investment sectors.

In 2007, this conflict became visible. Danish physicist Henrik Svensmark proposed a groundbreaking mechanism for how changes in cosmic radiation affect low-level cloud cover . The basic idea was based on pure physics: ionization of the atmosphere creates tiny particles (aerosols), which theoretically act as "seeds" for cloud formation, changing the Earth's reflectivity.

Shortly thereafter, astrophysicist Nir Shaviv expanded the theory, linking climate to the Solar System's journey through the spiral arms of the Milky Way. For a moment, climate variability was presented as a system of cosmic dimensions, completely outside the realm of climate diplomacy.

The need for answers led to the CLOUD experiment at CERN , led by Jasper Kirkby . The laboratory demonstrated that ionization from cosmic rays does indeed enhance aerosol formation. Measurements showed that these particles were extremely small. In the real atmosphere, the vast majority of them would not grow large enough to form clouds.

As economic interest in the “green transition” grew, pressure on skeptics increased. Researchers focusing on the solar factor saw funding cut and academic positions or stipends put at risk, as their work was deemed politically inconvenient, leaving carbon dioxide as the responsible cause of warming.

The Return to Hard Geopolitics

The most interesting twist, however, is being written in our own day, as the historical cycle is being completed with a touch of irony. In a world that is once again entering a trajectory of intense national antagonisms, the states that once led the green agenda are now redirecting their capital towards armaments, defense, and the heavy military industry.

The anthropogenic model and the urgent need to save the planet, which once constituted the crowning glory of international politics, are gradually receding into the background. The need for immediate power and energy survival proves that grand narratives are adopted or abandoned based on the strategic needs of each era.

The effort of Svensmark, Shaviv, and Kirkby opened up impressive horizons in physics. The quantitative data may not have justified them, but their path highlighted how powerful the gears that move scientific priorities are until the next crisis shuffles the deck again.

Svensmark, currently a researcher at DTU Space (Technical University of Denmark), continues to study the cosmic ray–cloud mechanism. Shaviv, a professor at the Racah Institute of Physics at the Hebrew University, continues to work on the astrophysical dimension of climate variability. Kirkby, head of the CLOUD experiment at CERN, continues to direct the CLOUD experiment, expanding the experimental base and its connection to satellite observations.

DefencePoint / Opinions, Sunday, July 5, 2026.

https://www.defence-point.gr/otan-ta-synnefa-skepazan-tis-klimatikes-afigiseis-michani-toy-chronoy