When Climate Becomes a Legal Obligation: What Heat-Related Liability Means for Contracts

From Exceptional Event to Foreseeable Threat

For most of the twentieth century, extreme heat sat comfortably in the legal category of the unforeseeable. Contracts excluded liability for it, insurers priced it as a tail risk, and governments treated it as an act of nature rather than a policy failure. That position is becoming increasingly difficult to sustain.

Writing on Verfassungsblog, legal scholars argue that heatwaves can no longer be distinguished from any foreseeable, cyclical event beyond state control, which means governments face positive obligations under Article 2 of the European Convention on Human Rights to protect lives from heat-related harm. With roughly 489,000 heat-related deaths occurring globally every year during the first two decades of this century, the scale of the problem is not in dispute. What is shifting is the legal framework used to apportion responsibility for it.

For in-house counsel and law firms, this shift carries implications that go well beyond constitutional litigation. If foreseeability is the test, then every party in a contractual chain who failed to plan for heat-related disruption becomes harder to excuse.

Force Majeure Clauses Are Being Quietly Stress-Tested

Force majeure provisions have long been drafted with natural disasters in mind: floods, earthquakes, pandemics. Heat, by contrast, has rarely appeared as a named event. Most boilerplate clauses rely on language such as "events beyond the reasonable control of the parties" or "acts of God." Both formulations are now vulnerable.

If courts and regulators, taking their cue from the ECtHR's reasoning on positive obligations, begin to treat heatwaves as foreseeable cyclical events, the argument that extreme temperatures constitute force majeure becomes considerably weaker. A logistics operator whose fleet cannot function above 40 degrees Celsius, a construction firm whose workers cannot legally be required to operate in dangerous heat, a data centre operator facing cooling failures: none of these parties will find it easy to invoke force majeure if the heat event was predictable in both timing and severity.

In-house teams should be auditing their standard contract templates now. The question is not whether a heatwave will occur but whether the contract allocates the resulting risk clearly and deliberately.

Supply Chain and Employment Contracts Carry Hidden Exposure

The liability question does not stop at the counterparty. Supply chains that run through southern Europe, North Africa or South Asia already face operational disruption from heat several weeks per year. As temperatures rise, those disruptions will lengthen and intensify. A manufacturer relying on components from a region where outdoor labour is increasingly restricted by heat-safety legislation is carrying a risk that should be priced, disclosed and contractually managed.

Employment contracts and service agreements also deserve scrutiny. European jurisdictions are beginning to codify heat-related workplace protections more formally. Spain, for instance, has introduced emergency protocols limiting outdoor work during extreme heat alerts. Where contracts specify deliverables without accommodating the possibility of lawful work stoppages caused by heat, they may create disputes that could have been avoided with clearer drafting.

The legal exposure here is symmetrical. Clients who insist on unrealistic delivery obligations during foreseeable heat periods may themselves be exposed if those obligations drive contractors to operate unsafely.

What Adira-Style Drafting Does Differently

This is precisely the kind of systemic, jurisdiction-specific risk that generic contract templates fail to capture. A clause drafted for a UK-headquartered company operating a supply chain in Greece or Portugal needs to reflect the heat-safety obligations that apply in those jurisdictions, the likelihood of heat disruption in those regions, and the way local courts have historically interpreted force majeure and frustration.

Adira reads contracts from the client's side of the table and works within the law of the jurisdiction in which a contract operates. That means flagging not just what a clause says but what it fails to say, particularly around foreseeable risks that the parties have not allocated. A heat-related disruption clause that is absent from a construction contract governed by Spanish law is a materially different omission than the same absence in a contract governed by Scottish law, and the drafting response should differ accordingly.

Generic AI tools that produce boilerplate without jurisdictional sensitivity will miss this. The risk is invisible until it is not.

The Broader Signal for Compliance and ESG Teams

The ECtHR's developing jurisprudence on climate and human rights is part of a wider regulatory direction of travel. The EU's Corporate Sustainability Due Diligence Directive, climate disclosure requirements and sector-specific regulations are all pushing in the same direction: foreseeable environmental risks must be identified, managed and disclosed.

Contracts are where those obligations become concrete. An ESG policy that acknowledges climate risk but sits alongside contract templates that ignore it is not a coherent legal posture. In-house teams and their external advisers need to close that gap before courts, regulators or counterparties close it for them.

Heat is no longer a metaphor for urgency. It is a legal risk, and it deserves to be treated as one.