As happens every summer, a column of our ViewsLetter must be dedicated to the phenomenon of global warming, a more accurate version of the usual expression “climate change”, which by comparison is much more neutral and sounds less alarming.
Just to provide some recent anecdotal evidence, in late June western Europe recorded its warmest June in the instrumental series — 20.74°C, some 3.05°C above the 1991–2020 mean, surpassing the record set only twelve months earlier. French temperatures exceeded 44°C on 23 June, with more than half the country under a red alert.421 stations, with forty years of history, set all-time highs, all but one of them in Europe between 22 and 30 June. Across the Atlantic, July delivered close to 3,000 broken daily American records; the most instructive reading came not from Phoenix but from Miles City, Montana, where the airport reached 114.9°F (46°C), beating its previous mark by a full twelve degrees Fahrenheit. And the summer before, China, Japan and Korea each endured their hottest season on record.
Compounding these episodes is the global phenomenon. The year 2024 closed at 1.55°C above the 1850–1900 baseline — the first calendar year past that threshold. The consolidated 2023–2025 average stands at 1.48°C, and the eleven years to 2025 are the eleven warmest in all eight principal datasets. Warming is neither uniform nor linear; it is, however, monotonic on any timescale longer than a decade. Even the negationists cannot negate global warming anymore. They moved the battle instead to a debate over the cause of the change.
For the proponents of the global warming theory, the attribution to human activity is undeniable. Carbon from coal, oil and gas are chemically distinctive (unusually light, because stripped of the radioactive carbon-14 that living matter contains, as they have spent millions of years underground). By burning fossil fuels, we produce CO2 (carbon-dioxide), so the increased carbon in the air captures oxygen. Guess what? The air has lost carbon-14 by exactly the amount burning fossil fuels would cause, while atmospheric oxygen has fallen by exactly the amount that burning would consume. That really looks like a “smoking gun”, rather than coincidence!
If that wasn’t enough proof, the stratosphere is cooling while the troposphere (closer to earth) warms, a signature incompatible with increased solar irradiance, which would heat both. Nights (when the sun is not out, by definition) are warming faster than days and winters faster than summers, again the reverse of what a brighter sun would produce. Additionally, satellite spectroscopy records a widening deficit in outgoing longwave radiation precisely at carbon dioxide’s absorption bands; and roughly nine-tenths of the excess energy has accumulated in the ocean, where no urban heat island can be blamed. Solar irradiance, meanwhile, has been flat to declining since the 1980s.
Against this, what do negationists say? The sceptical case has retreated through four positions in thirty years. First, that no warming was occurring — à position abandoned once the record lengthened and the 1998–2013 “pause” resolved into a step. Second, that warming was real but natural — cosmic rays, solar cycles, oceanic oscillations — which foundered on the evidence given above. Third, that it was caused by human activity, but only modestly so. Fourth, and now their dominant position, the jurisdictional turn: concede the science and contest the remedy. In the US, the EPA in February 2026 argued that the Clean Air Act never conferred authority over greenhouse gases at all, supplemented by the observation that American vehicle emissions would move global temperature imperceptibly in any case.
The only good news in all this is that the debate has migrated from physics to policymaking. Since global warming is now impossible to deny, let’s discuss how to counter it. Whether this will eventually lead to active policies or further paralysis is now the only question with an open answer.
