The overlooked networks of heat resilience

As extreme heat becomes more frequent and severe, many people are turning to informal adaptation strategies — rigging up plastic sheeting overhead for shade, sharing water at a community tap, and creating neighborhood cooling areas. A new commentary in Nature Climate Change, "Bringing justice to informal adaptation to heat stress," argues that this kind of grassroots resilience isn't a placeholder for "real" adaptation — it's essential work that formal systems routinely overlook. YSE News spoke with commentary co-author Brianna Castro, assistant professor of urban sustainability, about closing the gap and strengthening heat resilience in vulnerable communities. 

Q. What are the differences between informal heat adaptation and formal systems, and what do they look like on the ground?

Formal adaptation is what gets planned and funded through institutions — heat action plans, cooling centers, labor regulations, and infrastructure investment. It moves through official channels and shows up on a public timeline. Informal adaptation is what people do on their own alongside or in the absence of those systems. These actions include reinforcing a roof with plastic sheeting, resting during the hottest hours of the day, organizing water sharing at a community tap, and turning a courtyard or a school into a cooling space when nothing official exists nearby. It runs on local knowledge, trust, and proximity rather than official planning.

On the ground, though, these two systems are almost never cleanly separate. They're constantly interacting — informal practices fill in wherever formal systems are absent, underfunded, or too rigid to respond in timely ways. Formal programs often depend on informal networks to actually reach people. What we wanted to push back on is the assumption that informal adaptation is just a placeholder for something better. It's resourceful and often the only thing standing between a household and a dangerous heat wave, so it needs to be understood on those terms.

Q. How does the difference in treatment between informal heat adaptation and formal efforts impact vulnerable communities? 

When informal adaptation gets filed away as temporary, it becomes something that’s viewed as not worth investing in and something people are just expected to manage on their own. That has three concrete effects. First, the labor and knowledge behind informal adaptation receive no institutional recognition, so the people doing it stay outside adaptation planning entirely. Second, the costs of adaptation shift downward, onto whoever has the least, because informal adaptation runs on a household's own resources rather than public support. Third, when informal practices run up against official rules, they tend to get labeled as illegal rather than treated as the essential public function they are.

Q. Your commentary calls for a shift in authority, resources, and decision-making power in adaptation systems. What does this rebalancing entail and how will it provide a more equitable approach to heat relief efforts?

The shift is away from consultation, where communities get asked for input, toward shared authority, where communities have real power over what gets built, funded, and decided. Our commentary structures it as three institutional moves: recognizing informal knowledge and practices as legitimate rather than incidental; redirecting funding and technical support toward the people currently absorbing adaptation costs; and building decision-making arrangements where informal actors can shape priorities and hold institutions accountable for outcomes.

What makes this more equitable is that the people already adapting get a formal role in deciding how adaptation happens instead of having it decided elsewhere and delivered to them.