Archinect - News

Research finds a link between social vulnerability and urban heat island effect

2023-12-29T11:32:00-05:00

New research from two U.S. universities has drawn a link between socially vulnerable populations and urban heat island effect. The team, drawn from the University of Texas at San Antonio and Pennsylvania State University, used Philadelphia as a case study to summarize how more vulnerable people live in neighborhoods that are “less green and that get hotter.”

The research was recently published in the Journal of Buildings, and examines the differing characteristics of two Philadelphia neighborhoods to study how the way a neighborhood is built, and the characteristics of the people who live there, are both related to how hot it gets. The team found a “clear link between outdoor temperature and specific urban characteristics” before asking “whether these urban characteristics can be related to the social vulnerability of the residents.”

The social vulnerability of different Philadelphia neighborhoods. Image credit: Research team, licensed under CC BY-ND

The group established a social vu...

Planting trees could lead to fewer heat-related deaths in urban areas, according to a new study

2023-02-03T17:32:00-05:00

A new scientific study has shown the positive correlations between public health and tree planting in urban areas.

In a report published recently by The Lancet medical science journal, a team of European researchers shared data on mortality rates in 93 cities in the summer of 2015 that showed how premature deaths caused by urban heat islands can be mitigated through increased greening strategies.

The study found 6,700 premature deaths in that period related to the phenomenon. One-third of those deaths, according to the authors, could have been prevented by adding 30% more trees in the urban environments of each city. The data supports established notions that particularly low-income communities can benefit from resiliency measures, adding to a growing chorus of scholarship at a time when climate change is becoming a moribund issue for cities worldwide at an accelerated pace.

Ci...

Chief Heat Officer Eugenia Kargbo discusses extreme heat mitigation in Freetown, Sierra Leone

2022-08-09T14:30:00-04:00

Kargbo grew up to become a banker, but she has spent the last several years working in the administration of Freetown mayor Yvonne Aki-Sawyerr, a noted climate activist. Before becoming the city’s chief heat officer, she headed up the city’s sanitation department [...] Kargbo says her work is to keep climate change on the agenda, however many other things are tugging the world’s attention away.

A former aide to the noted climate activist Mayor of Freetown Yvonne Aki-Sawyerr, Eugenia Kargbo is one of five official Chief Heat Officers (CHOs) in the world. After being appointed in 2021, she joins fellow CHOs from Athens, Miami, Santiago, Chile, and Monterrey, Mexico in a program sponsored by the Atlantic Council’s Adrienne Arsht-Rockefeller Foundation Resilience Center (Arsht-Rock).

Arsht-Rock, along with the Extreme Heat Resilience Alliance (EHRA), developed and piloted the role of CHOs to have officials "charged with unifying the response to the challenge of heat to reduce risks and impacts of extreme heat for their residents and constituents."

For these officers appointed by local officials in their cities, much of the work entails attempting to consolidate their communities' disparate (and sometimes madcap) efforts to address climate issues that are too often spread between conflicting bureaucratic hierarchies.

Meet the current Chief Heat Officers. Image courtesy of Adr...

Monterrey, Mexico is the latest city to employ a full-time Chief Heat Officer

2022-06-17T14:45:00-04:00

In time for the start of summer, the global fraternity of Chief Heat Officers has grown as cities decide to commit themselves to full-time professionals from the subfield of public design in the face of mounting challenges caused by climate change.

The city of Monterrey, in the Mexican state of Nuevo Leon, recently announced architect and urban planner Surella Segú as the first-ever head of its new civic office, which is being funded through a partnership with the Atlantic Council’s Adrienne Arsht-Rockefeller Foundation Resilience Center (Arsht-Rock).

Surella Segú. Image courtesy Harvard University.

The 2018 Harvard Loeb Fellow is the principal and co-founder of EL CIELO, an 18-year-old practice with a focus on housing and urban renewal, and the former head of the Urban Development at the country’s Institute of the National Housing Fund for Workers.

A graduate of the Columbia University GSAPP and the ITESM, she now holds the fifth official CHO title under the Council's new City Cha...

NASA explores potential for green roofs to lower temperatures in cities

2022-05-30T09:02:00-04:00

Research undertaken by NASA has found that rooftop gardens can offer substantial temperature reductions in cities during summer months. In a study published in the journal Sustainable Cities and Society, the group used satellite imagery to measure temperatures at three rooftop gardens in Chicago compared to before the roof gardens were installed.

The research sought to understand ways of mitigating the “urban heat island” in cities, where the heat absorption and retention of materials such as concrete and asphalt can cause temperatures to be ten degrees higher in cites than in surrounding areas.

Related on Archinect: 10 green rooftop spaces we liked this week

“As cities grow and develop, they need to make good decisions about their infrastructure, because these decisions often last for 30 or 50 years or longer,” said Christian Braneon, a climate scientist and civil engineer at Columbia University and co-author of the study. “In the context of more frequent heatwaves and more extreme...

A fine-grained look at America's urban "heatscapes"

2019-08-13T18:37:00-04:00

As the United States suffers through a summer of record-breaking heat, new research shows that temperatures on a scorching summer day can vary as much as 20 degrees across different parts of the same city, with poor or minority neighborhoods often bearing the brunt of that heat.

Using a series of dramatic, color-coded maps, The New York Times highlights the growing disparity between exactly which neighborhoods in America feel the ever-increasing urban heat island effect. The report details stark temperature differences between the neighborhoods of several major cities, where temperatures can vary by as much as 20-degrees, depending on layout, urban design, and topography.

In Baltimore, for example, temperatures can range from 87-degrees in the city's wealthy suburban districts, where tree-lined streets and yards help to mitigate the heat island effect, to upwards of 101-degrees in the city's working class inner core neighborhoods, where tightly-clustered row houses and surface parking lots amplify the sun's power.

In Portland, Oregon, the temperature discrepancy between the city's leafy, park-adjacent westside and the industrial areas surrounding the airport in the northeast follows a similar trajectory. The city's massive Forest Park produces, according ...

How can cities become "heat-proof" and how does this affect the built environment?

2019-07-02T18:57:00-04:00

On top of climate change, cities grow hotter and hotter due to an increase in urban heat island effect. According to Philip Oldfield's Guardian piece, "What would a heat-proof city look like?," there are four solutions cities can implement to decrease rising temperatures. Oldfield explains green roofs/vertical gardens, reflective roofs, water treatments (ponds, pools, misters), and dynamic shades would aide in mitigating increased temperatures. However, before understanding these solutions, it is essential to point out what causes this rising heat phenomenon.

Image © Victor217 via freepik.com

Built environments worsen summer temperatures thanks to specific design elements and building materials. Asphalt and concrete absorb heat and bounce sun rays back onto street surfaces and surrounding areas. Tall buildings and glass skyscrapers create "urban canyons" which trap heat at ground level. Traffic and automobile dependency also contribute to heat emissions making city streets sizzling p...

Redevelopment plans for L.A.'s Pershing Square shift

2019-06-25T12:13:00-04:00

Plans for the much-touted Pershing Square Renew project in Los Angeles appear to be shifting.

Curbed reports that three years after being selected as the winning entry for an international competition to redesign the five-acre postmodern urban park, a team led by French landscape architects Agence Ter has shifted gears. Pershing Square is the oldest park in Los Angeles and its latest iteration was designed in 1996 by Mexican architect Ricardo Legorreta. The team's winning "radical flatness"-focused proposal has instead given way to a phased approach that will focus demolishing an existing concessions stand at the park in order to replace the structure with a new set of elevators serving the below-ground parking garage located beneath the park.

Pershing Square's latest iteration was designed in 1994 by Ricardo Legorreta. Image courtesy of Wikimedia user jjron.

The remaining plans involve other small fixes that focus on “taking down as many barriers as we can,” Debra Girod, a partner...

In Paris, concrete is out and trees are in

2019-06-20T13:05:00-04:00

Under a plan announced last week by Mayor Anne Hidalgo, thickets of trees will soon appear in what today are pockets of concrete next to landmark locations, including the Hôtel de Ville, Paris’s city hall; the Opera Garnier, Paris’s main opera house; the Gare de Lyon; and along the Seine quayside.

"Islands of freshness" are on the way to Paris, according to a recently-unveiled plan by mayor Anne Hidalgo.

The environmentally-aggressive mayor is aiming to have 50 percent of the city's land area taken up by permeable surfaces and planted areas, Citylab reports, and so, she is turning spaces around some of the city's most cherishes sites and monuments into mini-forests. A pine grove will come to a swatch of concrete in front of city hall, for example, while parking lots near Garnier's opera house will give way to a cherry orchard.

View of proposed changes to the areas around the river Seine. Image courtesy of Ville de Paris/Apur/Céline Orsingher.

The plan comes as Hidalgo prevails over legal challenges launched against her environmental makeovers along the Seine, where cars are limited, soon to be replaced with grasses and shrubs. The city's notorious boulevard périphérique is being reformatted, as well, with a lane of traffic taken away to plant trees.

Will the changes turn Pa...

How cool can paint really be? UNStudio collaborates with Monopol Colors to develop a paint that helps buildings fight solar radiation and elemental weathering

2019-02-27T20:16:00-05:00

UNStudio is known for their groundbreaking work in solution driven designs relating to the ever-changing urban environment. Climate is changing, which leaves architects and designers taking steps towards designing buildings and structures that can accommodate to the overheated urban environment. Intense heating and other weather conditions like rain and dust generate a lot of stress and strain on the exteriors of many buildings. Thirty to forty years ago, these types of conditions were not necessarily a priority. However, with the environmental conditions of today firms like UNStudio are taking a different approach to future building design. According to the studio's principal and founder Ben van Berkel, "designing with the future in mind also means buildings last longer in the face of environmental change. That they are more resilient to change and they endure environmental strain."

Theatre de Stoep in Spijkenisse, Image courtesy of UNStudio

Beyond the design process, materials play...

What would happen if LA replaced all its lawns with drought-tolerant landscaping?

2016-09-06T13:13:00-04:00

A new study by researchers at the University of Southern California found that replacing all lawns with drought-tolerant vegetation would have a net cooling effect of 0.2°C — but the science is less obvious than you might think. In fact, converting lawns has resulted in daytime warming of up to 1.9°C, mostly because of decreases in irrigation. But at nighttime, changes in soil thermodynamic properties, which strengthen sea breeze patterns, cool the city by 3.2°C.

In short, replacing all lawns would have significant, and beneficial, effects for public health. And, of course, it helps preserve already-scarce water supplies.

The study also seems to prove incorrect articles that suggested replacing lawns would make LA hotter.

For more on the on-going drought afflicting California, check out these links:

'Cool roofs' substantially reduce temperatures during a heat wave, according to new study

2015-12-22T19:39:00-05:00

It is well established that white roofs can mitigate the urban heat island effect, reflecting the sun's energy back into space and reducing a city's temperature. In a new study of Guangzhou, China, researchers found that during a heat wave, the effect is significantly more pronounced. Reflective roofs, also called cool roofs, save energy by keeping buildings cooler, thus reducing the need for air conditioning.

According to a new study by Berkeley lab researchers Dev Millstein, Ronnen Levinson, and Pablo Rosado, alongside Meichun Cao and Zhaohui Lin of the Institute of Atmospheric Physic in Beijing, so-called "cool roofs," or roofs painted white, substantially reduce the urban heat island effect during a heat wave.

Prior research had shown that cool roofs could mitigate the urban heat island effect, but the new study shows just how drastically this can make a difference during a heat wave. Heat waves affect both public health and energy resources, requiring massive amounts of air conditioning and other cooling systems that can overtax the electric grid.

"The hotter it is, the more cooling you get with cool roofs--and it is a significant difference, compared to the margin of error," Millstein told ScienceDaily. "We found that the stagnant conditions of a heat wave, where the air is just sitting over the city, was one of the main factors."

The research was conducted in Guangzhou, a large city ...

L.A.'s urban heat island effect accounts for temperatures up to 19 degrees hotter

2015-09-22T17:44:00-04:00

the greater L.A. area sees more additional heat than any other region, in part because of how urbanized it is. [...] Solutions include planting more trees and bushes, painting roofs white so they don’t absorb as much heat and using lighter colored concrete on streets and sidewalks.