Portugal is reeling from an unprecedented May heatwave, with temperatures soaring past 40 degrees Celsius in parts of the Algarve. The national weather service, IPMA, confirmed that this is the hottest May on record for the country, with anomalies of 10 to 15 degrees above the seasonal average. The heatwave, driven by a stationary high-pressure system over the Iberian Peninsula, has exacerbated drought conditions and sparked wildfires that have consumed thousands of hectares of pine and eucalyptus forest.
Climate models have long predicted that the Mediterranean basin would be a hotspot for extreme heat events. What we are witnessing now is the acceleration of that forecast. The physics is simple: greenhouse gases trap heat, and as the baseline temperature rises, the probability of extreme events increases exponentially. This is not a natural fluctuation; it is a signal of systemic change.
The implications for the European energy system are stark. Portugal derives a significant portion of its electricity from hydroelectric power, but reservoirs are at critically low levels. The heatwave also raises demand for cooling, which in a region with limited air conditioning infrastructure can prove deadly. In 2022, Europe recorded over 60,000 excess deaths from heat stress; this year threatens to surpass that figure.
Across the continent, governments are scrambling to update their heat action plans. France has already activated its colour-coded heat alert system, and Spain is considering mandatory air conditioning in new builds. But these are adaptations, not solutions. The root cause remains our reliance on fossil fuels. The European Union must accelerate its energy transition, which has been slowed by geopolitical pressures and internal disagreements.
A troubling aspect of this event is its timing. May is not yet summer, and the heatwave is arriving on the back of a winter that saw record low Albedo in the Alps due to reduced snow cover. The feedback loops are tightening. Less ice means more absorption of solar radiation, which means more heating, which means more ice melt. This is a machine that is now running away with itself.
Technological solutions exist. We have the capability to deploy large-scale solar power, to modernise grids, and to store energy in batteries and pumped hydropower. But the rate of deployment is still too slow. Portugal, for its part, has made progress: it closed its last coal power plant in 2021 and now runs on over 60 per cent renewables. But the heatwave shows that even this is insufficient without parallel efforts in efficiency and demand reduction.
The biosphere is sending us a message. The bleaching of coral reefs, the collapse of insect populations, and the migration of species poleward are all part of the same story. This heatwave is not just a weather event; it is a symptom of a planetary imbalance that we have caused. The question is whether we will treat it as a wake-up call or as a harbinger of worse to come.
In the newsroom, we often debate the language of crisis. Some argue that we risk desensitising the public. But the data does not allow for understatement. The concentration of carbon dioxide in the atmosphere is now 426 parts per million, a level not seen in several million years. The energy imbalance of the Earth is accelerating. Each tonne of emitted CO2 commits us to future warming. The urgency is calm because it is grounded in fact. We must act, not because we are panicked, but because we have done the maths.
As Europe braces for a summer that scientists have warned will bring more heatwaves, floods, and fires, the window for meaningful action is closing. Portugal’s record May is a data point in a trend that we can still alter, but only with immediate and sustained effort. The clock is ticking, and the temperature is rising.
