The climate crisis has made heatwaves more likely and more intense around the world. Record-breaking high temperatures are being reported across the world. According to international data, the first week of July 2023 was the hottest week on record, putting millions of people in danger. All throughout this summer, recurring heatwaves have been affecting large portions of Asia, Europe, and the United States, priming the land for fires in places like Greece, Spain, and Canada, triggering unhealthy air warnings, evacuations, and heat-related deaths. The increasingly threatening effects of the climate crisis are also felt in cities worldwide, as extreme heat proves to be a rapidly growing health risk to millions of urban dwellers.
Cities are on the front lines of this public health emergency. People living in urban areas are among the hardest hit when heatwaves happen, partly because of urban heat islands. This is a phenomenon that occurs when cities replace the natural land cover with dense concentrations of surfaces that absorb and retain heat, like pavements and buildings. Heat risk levels also vary by neighborhood, with less affluent and historically marginalized sectors being the most affected due to the density of the population, limited access to cooling systems, and the limited availability of green urban spaces.
Climate change has been one of the most pressing topics of this year, and for a good reason. Its effects are visible not only in natural habitats but also in urban environments. The construction industry has an important role to play in this dynamic. Throughout the year, events such as COP27 emphasized the importance of striving to achieve net carbon zero and the challenges faced by developing countries affected by increasingly devastating natural disasters. Possible directions for development include actions at varying stages and scales, from optimizing green spaces for urban heat control to employing local and innovative building materials to minimize the carbon footprint or passing laws that help create more sustainable urban and natural environments.
This article represents a roundup of articles published on ArchDaily during the course of 2022 with themes related to climate change and architecture’s potential to make a difference. It breaks down the topic into four main questions: What Are Cities Doing to Mitigate Urban Heat? How to Tackle Rising Sea Levels? What Was COP27 and Why Does It Matter? Can Building Materials Play a Role in Achieving These Goals? The last section presents an overview of new legislation approved during 2022 as a way of understanding how state and local governments are imposing this need for change.
The Transportation Alternatives and the Massachusetts Institute of Technology have initiated a new digital tool, Spatial Equity NYC, to help users understand how space is distributed and restricted across the neighborhoods of New York City. The tool asses the use of streets, sidewalks, and public spaces, as they are key factors that influence data such as pollution, traffic fatalities, accessibility, or air quality. The data collected shows a direct correlation between neighborhoods with low-income communities and communities of color and the detrimental ways in which public space is used, leading to health and mobility issues in those communities.
Urban green spaces are considered one of the most appropriate and accessible ways to mitigate the effects of rising temperatures in urban environments. As the global climate warms, cities worldwide face more frequent and extreme heat waves, putting their citizens at risk. Many cities are employing strategies for reducing the impact of urban heat islands, which are generated when natural land cover is replaced with surfaces that absorb and retain heat, such as pavements and buildings. This raises the temperature by several degrees compared to the surroundings. Cities have their micro-climate, influenced by this phenomenon combined with a series of often overlooked factors. For a climate strategy to be efficient, all factors need to be taken into consideration.
Kuwait is planning a 1,600-hectare development that will provide residential units, jobs, and amenities for 100,000 residents. Developed by URB, the ambitious project aims to promote a sustainable lifestyle with high standards of living, yet a low impact on the environment. The masterplan for the smart city is designed to optimize density and amenities distribution to create a walkable city, while also optimizing the green space ratio. This will help mitigate the effects of rising temperatures and the urban heat island effect. The green transportation systems and dedicated cycling tracks will make this a car-free city, apart from a ring road that allows for limited vehicular access. The city also promotes a circular economy that aims to provide food and energy security for the residents.
Cities across the Northern Hemisphere are preparing for the upcoming summer months, which are expected to be warmer and drier than average. The European Center for Medium-Range Weather Forecasts warns about temperatures rising above the norm in central and southern Europe this summer. Similarly, the forecast for the Unites States predicts hotter weather and below-average rainfall likely to fuel a megadrought. This poses threats for citizens, especially in larger cities, where heat-absorbing asphalt and waste heat generated by energy use create a “heat-island” effect. It translates to temperatures being up to 10°F (5.6°C) warmer in cities compared to the surrounding natural areas.
Prolonged heatwaves have been increasingly common in recent years, and cities are devising various strategies for combating the urban heat island effect. As Sydney experienced blistering summer temperatures of up to 50 degrees Celsius, the authorities have recently banned dark roofs on new homes and mandated lighter-coloured alternatives to reflect solar radiation. In Europe, Athens has taken the example of Miami and hired a Chief Heat Officer, tasked with finding coping strategies as the city confronts with heatwaves and wildfires that prompted a large number of residents to vacate the capital.
Bryggervangen and Sankt Kjeld’s Square in Copenhagen. Image Courtesy of SLA
For this month, The Dirt and author Jared Green share with us a study about urban heat islands, exploring new approaches that have been designed to both reduce urban temperatures and help communities adapt to a hotter world, In three cities: New York City, Copenhagen, and Abu Dhabi.
https://www.archdaily.com/962913/urban-heat-islands-are-increasingly-dangerous-but-planners-and-designers-have-solutionsJared Green
Mask Architects has been named one of ten winning teams in the Cool Abu Dhabi a global design competition. Their proposal, The Oasys, is a system where residents of Abu Dhabi can relax and enjoy outdoor spaces without feeling the heat. Selected from more than 1,570 participants across 67 countries, the project aims to tackle the effects of climate change through a localized solution for the urban heat island effect.
Last spring, the Los Angeles Bureau of Street Services tested a new, creative approach to combat the rising temperatures in the city center. The pilot project covered one neighborhood street in each of the LA's 15 council districts with CoolSeal, a more reflective asphalt-based coating developed by California-based company GuardTop. After seeing a difference of 11-13 degrees Fahrenheit on the coated streets, Los Angeles and other cities plan on implementing more reflective roofs and pavements to reduce the side effects of "heat islands."
More on the CoolSeal coating and the fight against heat island effect after the break.