When NATO leaders meet in Ankara, Turkey, this week, the primary focus will be on following through on 2025 commitments to increase defense spending significantly across the alliance. As last month’s record temperatures across Europe have shown, however, the territory NATO defends is now far trickier ground. NATO members must make investments that protect the food, water, transportation, energy, and health systems in the societies in which militaries operate.
Europe is sweltering, and its soldiers are no exception. France experienced its hottest day on record, 44.3 degrees Celsius, and at least 40 people drowned trying to escape the heat, while trains and nuclear plants shut down due to the temperature. Spain, Italy, Germany, and the United Kingdom all broke June records.
When NATO leaders meet in Ankara, Turkey, this week, the primary focus will be on following through on 2025 commitments to increase defense spending significantly across the alliance. As last month’s record temperatures across Europe have shown, however, the territory NATO defends is now far trickier ground. NATO members must make investments that protect the food, water, transportation, energy, and health systems in the societies in which militaries operate.
Europe is sweltering, and its soldiers are no exception. France experienced its hottest day on record, 44.3 degrees Celsius, and at least 40 people drowned trying to escape the heat, while trains and nuclear plants shut down due to the temperature. Spain, Italy, Germany, and the United Kingdom all broke June records.
As of June 28, the World Health Organization estimated more than 1,300 excess deaths across the continent since June 21—including around 1,000 in France alone—preliminary counts that officials expect to climb as mortality data firms up over the coming weeks. In the summer of 2022, heat killed nearly 62,000 people across Europe. In comparison, just 6,700 people died globally from terrorist attacks in 2022.
The U.K. Ministry of Defense’s Commander’s Guide to Heat Illness Prevention instructs officers to reconsider physically demanding activity whenever the Met Office issues a red heat warning—the kind seen across England this June. Extreme weather can affect the families and homes of troops, whether through required evacuations, school closures, or home damage—all of which affect troop morale and focus.
But the heat damages more than just people. At The Hague summit last year, NATO members agreed to spend 3.5 percent for core defense and up to 1.5 percent for resilience and related security by 2035. Preparing for extreme heat and other climate impacts is key to both. Core defense investments must include requirements matched to a warmer world, while resilience investments must include climate adaptation for critical civilian infrastructure.
Heat hits that infrastructure directly. It buckles and melts runways, bends rails, and makes repair harder and more exhausting. Britain’s Royal Air Force had to reroute planes to different runways in 2022 when the tarmac on one field at Brize Norton softened in the heat. Hot air is also thinner, so aircraft carry less, take off over longer distances, and climb less easily. The penalty is sharpest for helicopters, expeditionary operations workhorses.
Bastien Alex, a climate advisor to the French military, noted in the defense ministry’s own magazine that above 45 degrees Celsius, militaries must reconsider how helicopters are used in “high heat” theaters. As Alex noted, to fly the same mission in that heat may require two aircraft instead of one—and so an additional pilot, more fuel, and greater logistical support, all of which have to be anticipated and planned. The planning horizon is shifting quickly: A French study found that parts of some high-heat theaters could see 120 days a year above 45 degrees Celsius by 2050, against just five such days a year in the 2020s in the Sahel.
Members must also invest in what I call stability multipliers—the food, water, and energy systems that hold societies together under stress. Shocks brought on by extreme heat in low-income and climate-vulnerable countries can fuel instability, conflict, and displacement, with downstream effects on European security through migration pressures, disrupted supply chains, and increased demand for military and humanitarian engagement.
For example, in 2022, a March heat wave shriveled India’s wheat crop just as Russia’s invasion of Ukraine was choking Black Sea grain, prompting New Delhi to ban wheat exports. This compounded a global price spike that hit fragile importers like Sudan hardest, deepening the post-coup economic crisis on the eve of that country’s civil war. A new report from my organization warns the next shock could be worse: By 2040, climate change more than triples the odds of wheat crops failing simultaneously in India, France, and Germany. This scenario could increase European food prices as sharply as the first year of the Russia-Ukraine war and stir Arab Spring-style unrest in import-dependent NATO partners such as Morocco and Algeria.
This realistic hypothetical underscores that many NATO countries remain exposed to heat-driven risks to their own agricultural production, food distribution networks, and critical infrastructure. Building more regular mechanisms to convene resilience planners alongside energy and extreme weather experts and food security specialists can help NATO members plan for these risks and support more coherent use of resilience funding by linking military preparedness, civilian infrastructure protection, and food system stability.
Being unprepared for extreme weather also leads to more indirect risks from hybrid threat actors, who leverage disasters to push disinformation aimed at undermining societal trust in governments. For example, a Polish cybersecurity official noted the recent heat wave has led to an uptick in false social media messages blaming the event on the “global government” controlling the weather. This follows Moscow’s pattern of disinformation narratives blaming militaries for launching “weather weapons” or governments for spending money on Ukraine support instead of domestic resilience.
NATO must update its baseline resilience requirements to reflect these risks and help member states target resilience spending at them. These types of investments reflect a total defense concept—pioneered by Nordic countries—which is a whole-of-society approach that ties civilian infrastructure directly to military readiness. The newest NATO members, Finland and Sweden, are leaders in this approach and can provide a model for developing the resilience framework for the broader alliance.
Sweden’s 2024 National Security Strategy, for example, emphasizes the importance of maintaining Swedish food production for national resilience, as well as the role extreme weather can play in diminishing domestic agriculture. Finland shows what this looks like in practice. Its National Emergency Supply Agency requires six months but maintains reserves of roughly nine months of grainand obligates private companies to hold their own stocks of critical materials, buffering the country against a blockade or a failed harvest alike.
Another new tool at the alliance’s disposal is the Defense, Security, and Resilience Bank (DSRB), championed by Canada and set to advance at the Ankara summit. The DSRB aims to invest in innovations in defense and security and should ensure the investments it supports in defense tech consider resilience to extreme weather. The bank also plans to focus on supply chain resilience, another area in which integrating updated data and analytics on extreme weather trajectories would pay dividends for NATO member states.
The benefits of these approaches are how clearly they connect to the core mandate of the alliance. There’s no denying U.S. obstructionism on anything related to climate change and the reversal of many sensible climate-related policies at the Pentagon that have bled into NATO headquarters as well under the Trump administration. However, in an internal memo earlier this year, Defense Secretary Pete Hegseth noted that the Pentagon is still responsible for hardening installations against extreme weather and “assessing weather-related impacts on operations, mitigating weather-related risks (or) conducting environmental assessments.” The actions outlined above fall squarely in this definition.
Of course, NATO is not the only venue for this work. For European NATO members, the EU also matters—which has begun writing infrastructure resilience into binding law. The Critical Entities Resilience Directive has been in force since January 2023. It takes an all-hazards approach, naming extreme weather among the risks to essential services. Heat and storms, it warns, erode the capacity and lifespan of infrastructure when adaptation is missing. Member states must identify their critical entities by mid-July, and those entities must build in disaster-risk reduction and climate adaptation.
The European Commission has announced a European integrated framework for climate resilience, due for adoption late in 2026. It aims to make EU climate preparedness more ambitious and more coherent, through a mix of binding rules, economic instruments, and information tools. Two elements stand out.
One is a common 3-degrees-Celsius reference scenario that member states and sectors—defense included—would have to plan against. The other is “risk ownership”: clear responsibility, assigned sector by sector. Bilateral ties can reinforce all this. The U.K.-EU Security and Defense Partnership, agreed in May 2025, opens channels to align resilience investment with a post-Brexit Britain outside EU structures.
NATO member states need an approach that reflects today’s complex threat landscape, where climate change, hybrid threats, and global systemic shocks shape security within the alliance. NATO leaders must leave Ankara with a clear mission: Ensure defense spending commitments include extreme-weather adaptation, for civilians and forces alike.
