As temperatures rise globally, the impacts of urban heat islands—once considered an invisible threat—are becoming increasingly pronounced and ever more dangerous. Despite this mounting threat, however, the public realm which constitutes about 30% of cities offers immense potential to provide respite from scorching heat and introduce new opportunities to improve urban resilience efforts. As global temperatures rise, cities in regions like the United Arab Emirates and India are facing unprecedented challenges in maintaining livable urban spaces.

+

Tropical climates present significant challenges for urban environments, with extreme temperatures making outdoor spaces often uninhabitable for large portions of the year. The impacts of the urban heat island effect further exacerbate these conditions in cities and densely populated areas especially, intensifying the difference in thermal stress in urban settings compared to surrounding rural and suburban environments. This phenomenon, paired with the growing climate crisis, is becoming an increasingly formidable challenge in hot cities and tropical climates, where urban neighborhoods can feel up to 10-20 degrees C hotter than the surrounding countryside. Passive design strategies, which utilize natural elements and architectural features to maintain comfort without relying on energy-intensive systems, are becoming increasingly crucial to mitigate urban heat.Both India and the UAE prioritize shading, water integration, and vegetation in their passive design strategies to enhance sustainability. Both regions are also committed to fostering comfortable public spaces that promote social interaction. However, their approaches diverge in certain respects. The UAE adopts a top-down approach with ambitious, city-led pilot projects on a large scale such as.

The Abu Dhabi Climate Resilience Initiative. In contrast, India’s strategies often lean towards revitalizing and adapting traditional architectural elements and water management systems, aiming to blend modern needs with historical practices. This difference reflects varying contexts and priorities, yet both regions ultimately seek to create resilient and harmonious urban environments through innovative design and community engagement.In one of the world’s hottest climates, the UAE faces climate change and the rapidly intensifying threat of extreme heat head-on. As its residents increasingly seek air-conditioned spaces, promoting a healthy outdoor culture in hot cities such as Abu Dhabi presents a unique challenge and new opportunity to rethink public spaces. The Abu Dhabi Climate Resilience Initiative by CBT Architects is a citywide public realm improvement program that focuses on improving pedestrian thermal comfort levels in an outdoor desert climate through a series of tactical urban interventions. The initiative, pioneered by Kishore Varanasi, introduces three climate intervention pilot projects—a pocket park, a mosque plaza, and an urban intersection.

1- Multi-layered Cooling Approach

Abu Dhabi’s Climate Resilience Initiative introduces pilot projects that layer multiple cooling strategies. These include shading, evaporative cooling, conductive cooling, and convective/radiative cooling. The projects, such as a pocket park, mosque plaza, and urban intersection, are designed to create “cool zones” that optimize pedestrian comfort levels during peak usage times. The pilots carefully layer multiple cooling strategies to create a comprehensive ecosystem of “cool zones” that optimize and extend the time for pedestrian outdoor comfort level.

2- Innovative Shading Structures

The UAE is implementing distinctive vertical shade structures, such as those in the urban intersection pilot project. These structures are designed to protect pedestrians from both low and high-angle sun while also creating attractive communal meeting spaces. The designs often draw inspiration from traditional techniques, such as the Al Sadu weaving method. They also serve as a place for communal congregation.

3- Strategic Use of Materials and Vegetation

Abu Dhabi’s approach involves careful selection of materials with high albedo and low emissivity to reduce heat absorption. The pilots use lightweight concrete pavers and strategically placed aluminum walls. Additionally, native landscape plants and trees are incorporated to create microclimates that are cooler than the surrounding context.

India

As India grapples with record-breaking summer temperatures, with the national capital reaching a scorching 52.9 degrees Celsius in May this year, the need for innovative cooling strategies becomes imperative. Addressing this challenge requires a multifaceted approach that combines traditional wisdom with modern technology, urban planning with community engagement, and individual actions with large-scale infrastructure projects.

1- Traditional Heat Sinks 

In India, several towns are cities traditionally utilize Baolis or step-wells, a timeless solution that at once recharges groundwater while naturally cooling its surroundings. Serving as social centers, baolis historically brought communities together, fostering connections and providing respite from the heat in more ways than one. The revitalization of these existing structures, the rejuvenation of existing water bodies, man-made and natural, and reintegrating them into our urban environments can have a drastic impact on lowering temperatures while also forming important social nodes.At a master planning level, the allocation of surface area for built zones and open spaces should be based on water’s percolation potential, aiming to maximize local water conservation efforts. Drawing inspiration from traditional Indian baolis, modern infrastructure can incorporate water features and vegetation as heat sinks in urban areas, accommodating groundwater recharge as an essential part of development while forming essential heatsinks.

2- Building-level Heat Resilience 

While green building ratings and standards are gaining priority in the construction industry, individuals can also take conscious steps to mitigate heat within their homes and neighborhoods. Avoiding highly reflective surfaces on facades prevents heat from being redirected into the building’s environment. Incorporating chajjas (projecting eaves) and jaalis (perforated screens) are age-old techniques that are still very relevant today. Shaded balconies and green terraces can further shield interior spaces from direct heat gain.

3- Engaging Communities in Sustainable Planning

To make a lasting impact on how our cities grow, we need to adopt a collaborative approach to planning and design. Traditionally, Indian communities possessed inherent knowledge about constructing bunds and embankments, building in ways that minimize heat gain, and collectively maintaining local green cover.Involving local communities in planning efforts is crucial for the continued success of these initiatives. When citizens take the initiative in creating and sustaining change, and when all stakeholders actively engage in decision-making processes, they are more likely to understand and appreciate the significance of the efforts being undertaken. This collaborative approach fosters a shared vision for a healthier, more resilient, and sustainable future.

This article is part of an ArchDaily series titled India: Building for Billions, where we discuss the effects of population rise, urbanization, and economic growth on India’s built environment. Through the series, we explore local and international innovations responding to India’s urban growth. We also talk to the architects, builders, and community, seeking to underline their personal experiences. As always, at ArchDaily, we highly appreciate the input of our readers. If you think we should feature a certain project, please submit your suggestions.

This article is part of the ArchDaily Topics: Passive Architecture. Every month we explore a topic in-depth through articles, interviews, news, and architecture projects. We invite you to learn more about our ArchDaily Topics. And, as always, at ArchDaily we welcome the contributions of our readers; if you want to submit an article or project, contact us.