Resilient and Sustainable Cities in the Face of Climate Change

Cities are central to global sustainable development, but face unprecedented challenges with the advancement of climate change. The built environment has a significant impact on urban sustainability and climate adaptation of buildings. In 2014, the building sector accounted for 31% of global final energy use, 54% of final electricity demand and 8% of energy-related CO₂ emissions.

When we include upstream electricity generation, buildings were responsible for 23% of global energy-related CO₂ emissions. These figures highlight the urgency of implementing climate adaptation strategies in construction to create effective urban resilience.

The Context of Climate Change in Civil Construction

Climate change in civil construction represents one of the greatest challenges of the 21st century. These trends will persist and, by 2050, energy consumption is expected to increase by 20-50% compared to 2010 levels, according to the IPCC Special Report on the impacts of global warming of 1.5°C.

The construction sector also drives deforestation through construction materials and generates substantial waste and consumption of natural resources. Therefore, climate adaptation of buildings becomes essential to mitigate these impacts.

The Resilience of the Built Environment

Before delving into the details, it is important to understand the concept of urban resilience. According to the Intergovernmental Panel on Climate Change (IPCC), resilience refers to the capacity of a system or society to withstand and recover from the impacts of climate change.

This involves:

• Building adaptive capacity
• Strengthening coping mechanisms
• Reducing vulnerabilities
• Ensuring long-term sustainability

Climate adaptation in construction must consider all these aspects to create truly resilient buildings.

Thermal Comfort: Adaptation to Local Needs

One of the most important aspects when designing resilient buildings is the thermal comfort of occupants in the face of climate change. The thermal comfort ranges, proposed by Fanger in 1970 and by ASHRAE, assume that thermal neutrality provides greater comfort for most people.

Adaptation to the Brazilian Context

In the Brazilian context for example, where temperatures can be higher, it is necessary to adjust these comfort ranges for effective climate adaptation of buildings. Humans have the ability to adapt to different temperatures over time – what we call thermal adaptation.

Therefore, it is important to consider people’s thermal adaptability when establishing temperature limits. Although the range of 21 to 24 degrees Celsius is commonly used, it is essential to adjust these parameters in warmer regions to ensure occupants’ comfort.

Increasing Resilience at the Urban Scale

In addition to ensuring resilience within buildings, it is essential to increase urban resilience at the municipal level. Urban heat islands have intensified due to climate change, becoming a significant challenge for cities.

According to the IPCC 2023, approximately 3.3 to 3.6 billion of the global population live in areas highly vulnerable to climate change, and extreme climate events are becoming more frequent.

The Brazilian Scenario

In Brazil specifically, we face extreme climate events, such as increased droughts and heat waves. According to the Brazilian Panel on Climate Change (PBMC), the temperature increase in the country could be from 1°C to 6°C by 2100.

Predicted Regional Impacts:

• Central, North and Northeast Regions: Decrease in rainfall
• South and Southeast Regions: Increase in precipitation
• The entire country: Imbalance in rainfall patterns

These adverse impacts have significant consequences:

• Intensification of river droughts
• Direct impact on riverside and indigenous populations
• Compromised food security
• Fish scarcity and impact on agriculture

Therefore, increasing urban resilience in cities is crucial for climate adaptation.

Vulnerability and Susceptibility to Climate Change

Defining Vulnerability

Vulnerability refers to the sensitivity and capacity to adapt to the impacts of climate change. Communities with less response capacity and limited resources are more vulnerable to adverse effects, including:

• Low-income groups
• Marginalised populations
• Elderly and children
• People with chronic diseases

Understanding Susceptibility

Susceptibility is related to exposure and the likelihood of being affected by climate change. Communities located in risk areas are more susceptible:

• Coastal zones subject to flooding
• Regions prone to landslides
• Densely built urban areas

The Importance of an Integrated Approach

It is essential to consider the vulnerability and susceptibility of communities when developing urban climate adaptation policies and strategies. This involves:

Inequality Reduction Measures:

• Strengthening community response capacity
• Including all social groups in adaptation policies
• Investing in green infrastructure
• Promoting climate justice

Improvement of Basic Services:

• Access to drinking water
• Adequate sanitation
• Strengthening local governance
• More inclusive and participatory decision-making

Strategies for Climate Adaptation of Buildings

1. Energy Efficiency

• Use of materials with high thermal performance
• Advanced insulation systems
• Integration of renewable energies
• Building automation technologies

2. Bioclimatic Design

• Optimised solar orientation
• Utilisation of prevailing winds
• Strategic natural ventilation
• Adequate shading

3. Rainwater Management

• Capture and reuse systems
• Rain gardens
• Permeable pavements
• Green roofs

4. Resilient Materials

• Use of local materials
• Low environmental impact
• Increased durability
• Ease of maintenance

The Path to Resilient and Sustainable Cities

To make our cities more sustainable and resilient, it is essential to adopt a holistic approach that includes:

Smart Urban Planning

• Efficient energy use
• Adoption of renewable sources
• Creation of green areas
• Encouraging public transport

Investment in Research and Innovation

It is necessary to invest in research and innovations that can boost urban resilience, as well as engage the community and stakeholders to create significant changes in climate adaptation.

Role of Public Policies

I believe that effective public policies play a crucial role. Governments and local authorities need to adopt measures to:

• Encourage the construction of sustainable buildings
• Promote stricter regulations
• Develop awareness and education programmes

We try to do what we can on an individual scale, hoping that it contributes positively. However, I believe that there also needs to be intervention on a larger scale, through public policies and regulations for more sustainable development.

The Urgency of Climate Action

It really bothers me that green parties or candidates who prioritise climate and environment in their campaigns still do not capture public attention, even in the face of the current climate crisis, when our own future is at risk. My hope is that it will not be too late when we wake up.

Climate adaptation in civil construction is no longer an option – it is an urgent necessity. We need to act now to:

• Reduce carbon emissions
• Implement urban resilience strategies
• Prepare our cities for future climate scenarios
• Protect the most vulnerable populations

Conclusion: Building the Resilient Future

The pursuit of inclusive, resilient and sustainable cities is a global challenge. Through the development and implementation of effective climate adaptation strategies, we can ensure a better future for generations to come.

It is time to act and work together to build a built environment that promotes quality of life, social equity and preservation of our planet. Climate adaptation of buildings and urban resilience are the fundamental pillars for facing climate change in civil construction.

I hope this post has provided a comprehensive view on the importance of making cities sustainable and resilient. If you have questions or comments, do not hesitate to share them below!