Craig Mellow

One unbearably hot and dry summer might be dismissed as a fluke. For Europe, the summer of 2026 looks like a new normal. Proximity to the Arctic, among other reasons, makes Europe the fastest warming continent, which shows no sign of reversing.

"This is yet another structural change that the entire European economy has to go through," says Carsten Brzeski, global head of macro at ING Research.

The costs of extreme heat -- Paris and Rome have regularly reached 100 degrees Fahrenheit this season -- are harder to measure than those from the wildfires still raging in France and Spain. But they are real, says Hazem Krichene, senior climate economist at Allianz Research.

Sluggish, unproductive workers and higher energy costs could shave 1% annually off the gross domestic product of Southern European countries if the next five years match the hottest years since 2014, Allianz calculates. In theory that could wipe out economic growth. France's economy is expected to expand less than 1% this year.

Europe's southern flank is also most exposed to canceled tourist bookings. Tourism brings in well above 10% of GDP in Italy, Spain and Greece, Brzeski notes. Some drop looks inevitable, adds Michael Field, European equity strategist at Morningstar. "People going to Southern Europe in July and August is a thing of the past," he says.

Then there's the Rhine. The great river that emanates in the Swiss Alps and winds North to the Dutch port of Rotterdam is a Strait of Hormuz of sorts for the already beleaguered German heavy industry in between, and nearly as impassable right now. Water levels at the benchmark Kaub Gauge are already at record lows with little rain in the next few weeks' forecast, says Oleksandr Kulish, senior consultant at transportation specialist Transporeon. "The shallow barges that can get through carry just a fraction of normal volumes," he says.

That's a blow to chemical giants Bayer and BASF, both of which have their headquarters and biggest factories on the banks of the Rhine. Steel maker Thyssenkrupp has cut production at its furnace in the Rhine hub of Duisburg. Alternative shipping of inputs and outputs by rail or truck is more expensive, if you can find it. The European Union reports a shortage of 500,000 truck drivers and is searching for ways to attract them from "third countries."

The Old World's adaptation to new temperatures could spell profit for other enterprises, though, and not only hotels in Scandinavia or Scotland. Europe's aversion to air conditioning as a planet-killing American vice is eroding, Brzeski thinks. That could mean large catch-up investments. Around 20% of European homes are equipped with AC, compared with 90% in the U.S. In traditionally cool Germany, that number drops to an estimated 6%.

Continent-wide "climate adaptation investment" needs to increase by 0.6% of GDP, Allianz estimates. In raw numbers, that means $138 billion a year across the EU. A means to square comfort with environmental conscience is installing heat pumps, which theoretically reduce carbon footprints by drawing on electricity instead of natural gas, and can double as cooling devices in the summer. Heat pumps already account for half of new boiler sales in Germany. Japanese climate control giant Daikin saw European sales jump by 23% year-over-year in its latest reporting quarter.

A drive for cooling should mean still more investment in Europe's electricity grids, already under a capital-intensive overhaul to accommodate renewable energy and data centers, Field says. "If you're looking at who will benefit, utilities are a huge one," he says. His top picks in the sector are the United Kingdom's National Grid and France-based Engie.

Drought and the demands of both cooling and data centers may also move Europe to upgrade its leaky water systems, Field thinks. Close to 40% of H2O seeps out of aging pipes in the worst offenders like Spain or Ireland, he says. That could spell a boost for water managers like U.K.-based United Utilities Group.

Heat abatement will jockey with other urgent priorities for mental and policy bandwidth in Europe: defense buildup, trade tangles with the U.S. and China, "digital sovereignty," immigration, among others. "There are so many stories going on, and people are fed up with crisis talk," Brzeski says.

Still, 100-degree temperatures and scorched Bordeaux vineyards will tend to focus minds, and finance will follow.

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