France Prices Its Own Heat Wave at 10-15 Billion Euros, Against a 0.7% Growth Forecast

France's ecological transition minister, Monique Barbut, told an emergency drought meeting that this year's heat waves, wildfires and severe drought would cost the country between 10 billion and 15 billion euros, according to Le Monde ^[1]. Against a 2025 growth forecast of about 0.7% ^[3] and a damage estimate the ministry itself puts at 0.3% to 0.5% of GDP ^[2], climate stops being a disclosure exercise and becomes a line in the national accounts.

The arithmetic is blunt. The ministry says the figure could shave up to 0.5 percentage point off growth ^[2], which on the 0.7% forecast leaves roughly 0.2% ^[17]. The euro range implies a national economy of about 3.0 to 3.3 trillion euros ^[20], so this is not a rounding error dressed up as a crisis.

The caveat matters as much as the number. The ministry said the estimate was not produced by economists or macroeconomic experts and is an in-house figure based partly on the costs of past heat waves ^[4]. That is unusually candid, and it means the range is a policy signal rather than a measurement.

Outside estimates are worse. Triodos Bank, a Dutch investment firm, projected about 60 days above 30 degrees Celsius in France this year, 41 more than the past average of 19 ^[5], roughly 3.2 times the historical count ^[22]. It said the effect on labour productivity, agriculture, energy and transport could cut French growth by up to 1.5 percentage points ^[6], which against the 0.7% forecast implies about minus 0.8% ^[18]. Triodos also put EU-wide heat losses at about 180 billion euros, as reported by Der Spiegel ^[15], while the European Commission projects EU growth of 1.1% ^[16] and earlier estimates suggested Europe's heat could cut EU GDP by about 1% ^[14]. Note that France's own upper bound of 15 billion euros is only about 8% of that EU total ^[21], well below France's share of the bloc's output. Either Paris is being conservative or Triodos is being aggressive.

The physical readings are not in dispute. On the 13th, 80 of 96 mainland departments, about 83% ^[19], were under orange heat alerts, with highs forecast at 38 degrees around Paris and 40 in the southwest ^[10], in the country's fifth heat wave of the year following major wildfire damage late last month ^[9]. More than 40,000 people face tap water disruptions ^[12], and in about 43% of French rivers flow has stopped or the river has dried out, the most severe reading for this time of year since observations began ^[13].

For anyone modelling this, the timing is the trap. Agricultural losses can only be confirmed after the harvest, and structural damage such as cracks from soil shrinkage may surface months later ^[7]. Some sectors get a short-term lift instead: air conditioning and insulation demand, cafe terraces, and higher electricity consumption ^[8]. A sovereign macro variable that resolves on an eighteen-month lag is one that gets underpriced in real time.