The planet has entered uncharted thermodynamic territory. According to a new analysis from the UK Met Office and the University of East Anglia, the global average temperature for the past 12 months exceeded pre-industrial levels by 1.5°C for the first sustained period. This is not a model. It is a measurement. The data, drawn from thousands of stations across land and sea, shows that the 12-month rolling average from July 2023 to June 2024 reached 1.52°C above the 1850-1900 baseline. That is 0.02°C above the symbolic Paris Agreement threshold. The symbolic boundary has been breached not as a single spike but as a persistent state.
The statement from the Met Office is characteristically understated for a British institution. They describe the findings as 'a stark reminder of the urgent need to reduce greenhouse gas emissions'. But the numbers scream where the language whispers. Each of the past 13 months has set a new monthly temperature record, a sequence without precedent in the 174-year instrumental record. The North Atlantic has been running at temperatures 1.5°C above the 1991-2020 average, a departure that oceanographers call 'off the charts'. The Arctic sea ice minimum in September 2023 was the sixth lowest on record, but the rate of loss remains a relentless 12% per decade.
Professor Tim Lenton, director of the Global Systems Institute at the University of Exeter, describes the situation with a geological analogy: 'We have been walking up a slope of gradual warming, but now we are stepping onto a plateau where the heat is accumulating faster than our systems can adapt. This is not a tipping point, it is a new equilibrium.' The data supports his assessment. Estimates from the European Union's Copernicus Climate Change Service indicate that the Earth Energy Imbalance, the net heat absorbed by the climate system, has doubled since 2005. We are storing energy at a rate equivalent to four Hiroshima bomb detonations per second.
The reaction from the policy sphere has been predictably performative. The UN Secretary General António Guterres called for 'climate action on all fronts', while the UK Prime Minister's spokesperson reiterated the government's commitment to net zero by 2050. But the physics does not negotiate. The concentration of CO2 in the atmosphere is now 420 parts per million, 50% higher than pre-industrial levels. Methane, a far more potent greenhouse gas, is at 1,900 parts per billion, more than double historical levels. The last time such concentrations existed, the planet was 3°C to 4°C warmer, and sea levels were 20 metres higher.
The implications for the energy transition are stark. The UK's own Climate Change Committee has warned that current policies are not enough to meet legally binding carbon budgets. Renewable energy deployment is accelerating, but it is not enough. Solar and wind now supply 14% of global electricity, a record, but fossil fuels still provide 82% of primary energy. The International Energy Agency projects that global oil demand will peak before 2030, but that will not be soon enough to avoid the consequences now manifesting.
There is a psychological dimension to this moment. The 1.5°C target was always a political construct, a line in the sand drawn by diplomats. But the planet does not recognise human boundaries. It responds to forcing. The current rate of warming, 0.3°C per decade, is unprecedented in the geological record for interglacial periods. We are now in a climate regime that has no analogue in human history. The British scientists who compiled this report are not alarmists. They are data analysts. And their data is clear: we have entered a new climate era. The only remaining question is how much worse it will become.
As a science correspondent, I have spent the last two decades reporting on the gradual accumulation of evidence. This is not a gradual report. It is a hammer. The numbers are no longer projections. They are measurements. The planet is warming, and it is warming faster than we can adapt. The calm urgency of the scientific community is about to break. The next breaking story may not be a temperature record. It may be the collapse of a major ice sheet or the failure of a critical ecosystem. We should not pretend otherwise.
