Cities Can No Longer Prepare for Yesterday’s Climate

Adaptation to extreme temperatures must become a permanent part of urban infrastructure

The heatwaves affecting Europe and the United States should not be treated as isolated events that end when temperatures fall.

They are exposing a structural gap: many cities were designed for climate conditions that no longer reflect present-day reality.

Homes, power grids, transport systems, streets and public spaces were built around historical temperature ranges. Today, those limits are being exceeded more often and for longer periods.

The problem is not simply that temperatures are rising.

The problem is that cities continue to operate as though extreme heat were still unusual.

From temporary response to permanent adaptation

The standard response to a heatwave remains largely informational: drink water, reduce physical activity, close blinds, avoid the hottest hours of the day and check on vulnerable people.

All of this is necessary.

But it can no longer remain the main strategy for urban adaptation.

When extreme temperatures become recurrent, they stop being only a weather emergency. They become a new operating condition for the city.

Adaptation must move beyond seasonal campaigns and become permanent infrastructure.

Cities need to begin answering more demanding questions:

Can an older person travel from home to a health centre without walking through streets fully exposed to the sun?

Can a building maintain safe indoor conditions during a power cut?

Are there clearly identified public places where people can hydrate and safely lower their body temperature?

Can the power grid support thousands of cooling systems operating at the same time?

Do the most vulnerable neighbourhoods receive priority investment, or must residents depend entirely on their own financial resources?

These are not only public-health questions.

They also concern urban planning, mobility, housing, energy, emergency management and social equity.

A new form of urban climate infrastructure

Cities already rely on dedicated infrastructure to manage specific risks.

They have drainage networks, fire-protection systems, flood barriers, civil-protection shelters, structural building codes and emergency exits.

Extreme temperatures now require infrastructure of their own.

Urban Climate Infrastructure should bring together the spaces, services and systems needed to keep cities habitable when temperatures move beyond normal operating conditions.

This is not simply about installing more air conditioning.

It is about creating an integrated network that combines:

• climate shelters;
• protected corridors;
• hydration points;
• continuous shade;
• housing retrofits;
• backup energy;
• climate-adapted transport;
• public information;
• support for vulnerable people;
• environmental monitoring technology.

Green infrastructure remains essential. Cities need trees, parks, permeable surfaces, water features and materials that absorb less heat.

But newly planted trees may take years to provide adequate shade. A green square does not solve overheating inside a home. A park does not protect someone who must walk twenty minutes to reach a train station.

Vegetation must form part of the system, but it cannot be the only response.

Climate shelters integrated into the city

Libraries, schools, sports centres, stations, universities, shopping centres and municipal buildings could form part of a permanent network of climate shelters.

These spaces should be clearly signposted, accessible and included in official maps and city applications.

A climate shelter should offer more than cooling. It could also provide drinking water, toilets, seating, device charging, first aid, official information and links to health or social services.

Under normal conditions, these buildings would continue to serve their everyday purpose.

During an alert, they would become part of the city’s public-protection infrastructure.

The challenge is not simply to open a few centres when conditions worsen.

It is to build a measurable network whose coverage and location reflect the actual vulnerability of each neighbourhood.

Micro-shelters in streets and high-exposure areas

Smaller structures could be installed between major climate shelters: urban micro-shelters, or Climate Pods.

These spaces would allow people to rest, hydrate and temporarily lower their body temperature before continuing their journey.

They could be located in squares, along major avenues, at transport interchanges, near hospitals, in commercial districts and around care homes.

Depending on their design, they could include efficient cooling, ventilation, drinking water, seating, environmental sensors, phone charging, municipal information and basic emergency equipment.

They would not be hospitals or long-term shelters.

They would function as intermediate recovery points within a broader urban network.

The distance between them should not be arbitrary. It should be determined by temperature, pedestrian flows, available shade and the presence of vulnerable populations.

Corridors that allow people to move without dangerous exposure

Creating safe spaces is not enough when reaching them requires prolonged exposure to extreme temperatures.

Cities should develop climate-protected corridors connecting stations, hospitals, care homes, schools, community centres and climate shelters.

These routes could combine canopies, mature trees, reflective surfaces, drinking-water points, rest areas and clear signs indicating cooler routes.

In some locations, cities could also develop indoor links, covered walkways or partially underground connections.

Cities exposed to extreme cold have already created protected networks that maintain mobility during severe winter conditions. Canada provides several examples of indoor and underground links connecting transport systems, buildings and public services.

Cities exposed to extreme heat should study the same principle: a second layer of urban mobility protected from outdoor conditions.

The goal is not to copy one particular model.

It is to recognise that people must still be able to move through the city during extreme weather.

Housing adaptation cannot depend entirely on homeowners

The home is one of the main barriers protecting people from extreme temperatures.

It can also become a heat trap.

The most vulnerable buildings are often occupied by residents with the least capacity to finance improvements. Residential adaptation cannot therefore be treated solely as an individual responsibility.

Thermal renovation should be recognised as an investment in public health and urban continuity.

Public programmes should help finance insulation, external shutters, cross-ventilation, reflective roofs, solar protection, better windows, passive cooling and efficient energy systems.

Priority should be based on population vulnerability and the thermal performance of the building, not only on the owner’s ability to pay.

New building codes should also assess how long a home can maintain safe conditions when electricity fails or mechanical cooling stops working.

A building that is efficient under normal conditions is not necessarily resilient during an emergency.

The private sector must also participate

Urban adaptation will require investment on a scale that municipalities are unlikely to meet alone.

Private participation could accelerate the deployment of climate shelters, cooling zones, hydration stations, energy systems and public-information infrastructure.

Companies could help finance these systems through seasonal sponsorships, annual contracts or multi-year agreements.

In return, they could receive regulated visibility within the spaces.

A company might finance drinking water, maintenance, solar energy, sensors or cooling systems, while associating its brand with infrastructure that directly benefits the public.

Outdoor advertising systems could also switch automatically during alerts to display temperature information, air quality, hydration points and the nearest climate shelters.

Public purpose must remain the priority. But part of the investment currently directed towards urban advertising could be transformed into measurable climate infrastructure.

The aim is not to fill public shelters with advertising.

It is to turn marketing into a tool that also helps protect people.

Climate-safe public transport

A climate-adapted city cannot stop at the entrance to a metro station.

Public transport must become part of the city’s protection system.

During periods of extreme heat, millions of people depend on metros, trains and buses. Yet many systems still operate with insufficient ventilation, inconsistent cooling and vehicles designed for milder conditions.

Cities should ask a basic question:

Can a vulnerable person use public transport during a heatwave without putting their health at risk?

Each metro or train could include a clearly identified climate-priority section for:

• older passengers;
• pregnant women;
• people with cardiovascular or respiratory conditions;
• passengers with reduced mobility;
• adults travelling with young children;
• anyone showing signs of heat exhaustion.

These areas could offer stronger ventilation or cooling, priority seating, direct communication with staff and clear information about heat-related symptoms.

Ventilation and climate control should respond automatically to real conditions inside the vehicle, including temperature, humidity, CO₂ levels and passenger density.

They should not depend solely on the season or manual decisions.

Defibrillators should also be more systematically integrated into transport networks. It may not be practical to place one in every carriage, but each train unit or major platform could have a clearly marked device connected to a proper maintenance and emergency-response protocol.

Hydration is better organised through stations, interchanges, concourses and major platforms, with emergency supplies available during severe alerts.

Major stations could operate as climate-resilience hubs, offering:

• cooled areas;
• drinking water;
• seating;
• first aid;
• defibrillators;
• device charging;
• official information;
• trained staff;
• links to health services;
• directions to nearby climate shelters.

Public transport should not merely move people through the city.

During extreme weather, it should also help protect them.

Transformation can begin with a single street

Cities do not need to wait until they have a plan for transforming their entire territory.

Adaptation can begin with a pilot project.

One street.

One square.

A route between a station and a hospital.

A commercial district.

A neighbourhood with high levels of vulnerability.

The pilot could combine shade, drinking water, less heat-absorbent paving, one main shelter, several micro-shelters, environmental sensors and public-private funding.

Then it should be measured.

How many people used it?

How much did it reduce thermal exposure?

Did the infrastructure work during the most critical hours?

How much did it cost to maintain?

Did it improve access for vulnerable residents?

What needs to be changed?

Urban transformation should grow from evidence, not only from political announcements or symbolic installations.

Pioneer cities can establish an international reference

Major cities such as Dubai, Paris, London, Madrid, Athens or a Scandinavian capital could develop the first reference projects.

Each would contribute a different context.

Dubai could test advanced solutions for extreme heat.

Paris could demonstrate how to adapt a dense historic city without losing its identity.

London could integrate climate shelters with transport and existing buildings.

Madrid or Athens could focus on vulnerable neighbourhoods and residential retrofitting.

A Scandinavian capital could develop governance, energy and multi-hazard resilience models.

A pioneer city should not simply host an intervention.

It should help create a new standard that other cities can adapt.

Building a new urban discipline

Climate adaptation can no longer remain a collection of disconnected initiatives.

It needs to become an organised discipline bringing together urban planners, architects, engineers, climate scientists, public-health experts, mobility specialists, companies, universities and emergency-management professionals.

No Signal The Guide proposes opening this conversation and contributing to the development of a technical framework capable of turning these ideas into real projects.

The vision may begin as a civic initiative.

But its development must be collaborative, technical and measurable.

Cities must decide which climate they are building for

For too long, urban development has focused on efficiency, growth, transport and connectivity.

It must now accept another responsibility: preserving habitability when climatic conditions move beyond what has historically been considered normal.

Cities can no longer prepare for the climate they once had.

They must begin designing for the climate they already have and the one they are likely to face over the coming decades.

Adaptation is not only about helping people endure the heat.

It is about transforming the city so that extreme temperatures do not exclude them from it.

And that transformation can begin today, with a single street.