Cities Can’t Afford to Keep Treating Trees Correctly

Cities Can’t Afford to Keep Treating Trees Correctly

A quiet urban street corner with sunlit trees and scattered autumn leaves. by Pexels User via pexels

Cities can't afford to keep treating trees like decoration
07-03-2026

Cities can’t afford to keep treating trees like decoration

GoogleFollow Earth on Google

Stand under a big old tree on a sweltering afternoon and you’ll understand something city planners are only now starting to take seriously: that shade isn’t decoration. It’s doing a job.

Trees are cooling the block, catching stormwater before it floods the street, and scrubbing pollution out of the air a person’s actually breathing.

A new study, written by more than 60 scientists spanning dozens of countries, makes the case that most cities still can’t quite bring themselves to treat trees like the infrastructure they clearly are.

The team behind it is led by Manuel Esperon-Rodriguez from Western Sydney University and Bangor University, with Mark G. Tjoelker from Western Sydney University as senior author.

Trees need time to grow

You can plant a sapling in twenty minutes. Growing an actual canopy, the kind that meaningfully cools a neighborhood though, takes decades.

So when a mature tree comes down, a city doesn’t just lose a tree. It loses thirty or forty years of accumulated shade, habitat, and carbon storage, and there’s no fast way to buy that back.

And yet trees keep losing these fights. Developers clear them because it’s cheaper and faster and penalties for illegal removal are often too weak to sting.

City budgets tend to fund the planting photo-op but not the years of watering, pruning, and pest management that actually keep a tree alive.

The researchers want stiffer enforcement, real tax incentives for landowners who keep mature trees standing, and minimum canopy requirements written into law rather than left to goodwill.

They even suggest big infrastructure projects, the kind that usually flatten everything in their path, could be redesigned to grow canopy instead of erasing it.

Not every neighborhood gets the shade

Wealthy neighborhoods, almost everywhere researchers have looked, tend to be noticeably leafier than poor ones.

Meanwhile, it’s the low-income neighborhoods that usually catch the worst of the heat and the dirtiest air.

The trees, in other words, tend to show up exactly where they’re needed least.

Closing that gap takes more than a citywide average that quietly hides the worst blocks.

Greening neighborhoods without displacing residents

The authors want targets set neighborhood by neighborhood.

They also want the people who actually live there, including Indigenous communities, involved in deciding what gets planted and where – rather than having greenery imposed on them from a planning office.

There’s a warning too: planting lots of trees without a plan can trigger green gentrification, raising rents and pushing out the very residents the trees were meant to benefit.

The only real fix, the researchers argue, is tying tree policy directly to housing policy instead of treating them as two separate departments that never talk.

Trees barely show up in climate policy

Given how much trees do, it’s almost strange how absent they are from the major climate and biodiversity agreements that actually move money and political will.

The authors want that fixed, with urban forests written explicitly into national climate plans, biodiversity strategies, and the commitments countries make under frameworks like the Paris Agreement.

Money remains the sticking point. Estimates put the global price tag for nature-based climate solutions, urban forests among them, at well over $500 billion a year.

Most current funding covers the ribbon-cutting moment of planting a tree and stops right there, leaving the decades of upkeep that actually determine whether that tree survives unfunded and, often, forgotten.

The study points to newer tools like green bonds, biodiversity credits, and tracking programs such as Tree Cities of the World as ways to start closing that gap, rather than continuing to fund trees like a one-time expense.

Many cities fail to keep record of trees

Maybe the most surprising finding here isn’t political, it’s logistical. Plenty of cities simply don’t keep good records on their own trees.

Nobody’s tracking which newly planted saplings actually survive their first few summers, which species are struggling, or how unevenly canopy is spread across town.

Without that information, cities are essentially guessing whether their tree policies work at all.

The scientists push for cheaper, sharper tools, satellite imagery, AI-assisted monitoring, to close that data gap, especially for less rich cities.

City trees should be diversified

The team also flags a quieter risk: planting the same few species block after block. It looks tidy, but it’s fragile.

One well-timed pest or disease can wipe out an entire city’s canopy in a single outbreak.

Instead, the researchers argue that cities should diversify their tree populations. Non-native species can be included where they are well suited to a hotter, drier future.

At the same time, cities should continue prioritizing native trees while respecting the ecological and cultural context of each place.

An urgent problem

A city’s trees aren’t a nice-to-have thing that gets funded once the “real” priorities are covered.

They’re already doing the work of public health policy, climate defense, and neighborhood fairness, whether or not anyone’s paying for it that way.

The authors don’t treat this as a distant problem. Cities keep growing and heatwaves keep getting worse.

Thus, the decisions being made right now – about which trees get to stay standing and which neighborhoods get to keep their shade – will quietly decide how livable those cities feel for decades after the people making those decisions are gone.

The study is published in the journal PLOS One.

—-

.

 

.

We Can’t Air-Condition Our Way Out of a Hotter Future

We Can’t Air-Condition Our Way Out of a Hotter Future

Beige concrete building with air conditioning units under a clear blue sky, showcasing minimalist urban architecture. by Abdelrhman Magdy via Pexels

.

 

We can’t air-condition our way out of a hotter future, says UNSW expert

UNSW Newsroom – 2 July 2026
Samantha Dunn
Samantha Dunn

A new global review argues passive cooling technology must become central to climate adaptation.

As temperatures rise around the world, air conditioning is saving lives. But a growing reliance on it is also placing unprecedented pressure on electricity grids, increasing greenhouse gas emissions and making cities even hotter.

A global review led by UNSW Sydney’s Professor Mat Santamouris AM – an expert in innovative heat mitigation technologies and strategies for cities, opens in a new window – argues that keeping buildings cool without relying solely on air conditioning will be critical for adapting to climate change.

Published in Nature Reviews Clean Technology, opens in a new window, the review examines the latest advances in passive cooling technologies, from emerging materials for radiative, evaporative and combined radiative/evaporative cooling to sophisticated solar control systems and personalised intelligent ventilation technologies that can help buildings shed heat without consuming electricity.

Prof. Santamouris says passive cooling should no longer be viewed as a niche architectural feature, but as essential infrastructure for a warming world, opens in a new window.

“Air conditioning saves lives and will remain essential during extreme heat,” he says. “But we cannot air-condition our way out of climate change. If every building depends entirely on mechanical cooling, we create enormous pressure on electricity systems while adding even more heat to our cities.”

 Summer street scene in Firenze, Italy, during a heatwave. People walking under the strong Tuscan sunlight with refreshing water mist in the urban atmosphere.

As European cities experience some of their hottest recorded temperatures over recent weeks the question about how to keep populations cool is front of mind.Photo: Richard Vanlerberghe / Unsplash

Demand for cooling is soaring

The review highlights the rapid growth in cooling demand worldwide, opens in a new window. Global electricity consumption for cooling has reached almost 10 per cent of total electricity use, opens in a new window, with around 10 new air conditioners sold every second, opens in a new window. By 2050, the number of residential air-conditioning units is projected to increase to almost 5.6 billion worldwide, opens in a new window.

At the same time, billions of people living in hot climates still lack access to affordable cooling, opens in a new window.

Cooling buildings without relying on air conditioning

Passive cooling technologies, opens in a new window offer a way to reduce energy demand while making buildings safer and more comfortable, particularly for vulnerable communities.

“The best cooling strategy is to stop unwanted heat entering buildings in the first place. Shading, reflective materials, opens in a new windowsmarter ventilation, opens in a new window and new cooling materials can dramatically reduce indoor temperatures before an air conditioner even needs to switch on,” says Prof. Santamouris.

Rather than replacing air conditioning, Prof. Santamouris and coauthor Dr Konstantina Vasilakopoulou from RMIT argue passive cooling should become the first layer of defence, with mechanical systems providing additional cooling only when required.

The review evaluates emerging innovative technologies, such as super-cool materials, combined radiative/evaporative coatings, sophisticated external shading systems and personalised ventilation, as well as known passive cooling technologies such as reflective cooling materials that release heat directly into the atmosphere and hybrid cooling systems that combine multiple passive approaches.

Integrating passive cooling strategies with efficient building design could reduce cooling demand by as much as 80 per cent, opens in a new window in hot climates while lowering peak electricity demand and improving resilience during power outages, according to the review.

 

The buildings we construct today will still be standing in 2050 and beyond. They need to be designed for the climate they will experience, not the climate we had in the past.
Professor Mat Santamouris AM

Cooler cities, healthier communities

Beyond reducing energy use, the researchers say passive cooling can make cities healthier and more resilient as extreme heat events become more frequent.

Keeping buildings and neighbourhoods cooler can reduce the risk of heat-related illness, ease pressure on electricity networks during heatwaves and improve comfort for people who cannot afford to run air conditioners. Passive cooling measures can also help buildings remain safer during power outages, when mechanical cooling systems are unavailable.

Prof. Santamouris says the greatest benefits will come from combining passive cooling with efficient air conditioning, rather than treating them as competing approaches.

“There is no single solution to keeping cities cool. We need a whole-system approach that starts with climate-responsive building design, shading and better materials, then uses the most efficient cooling technologies only when they are really needed.”

The review calls for stronger building standards and planning policies that encourage climate-responsive design, alongside investment in technologies that reduce heat entering buildings and lessen demand on electricity infrastructure as cities continue to warm.

Designing buildings for tomorrow’s climate

Buildings designed today will need to withstand a much hotter climate over coming decades, says Prof. Santamouris.

“The buildings we construct today will still be standing in 2050 and beyond. They need to be designed for the climate they will experience, not the climate we had in the past.”

In order to achieve this governments should strengthen building standards, support passive cooling technologies and improve access to affordable cooling for lower-income communities.

Prof. Santamouris says these measures could deliver significant benefits for public health, energy security and climate resilience.

“Cooling should not be a luxury available only to those who can afford rising electricity bills. Better building design can reduce costs, improve comfort and help protect the people most vulnerable to extreme heat,” he says.

.

 

[subscribe2]

.

The 2026 World Cup is the Greatest Architectural Experiment

The 2026 World Cup is the Greatest Architectural Experiment

Iconic FIFA soccer ball and Vancouver stadium, showcasing urban sports architecture. by The Six via Pexels

.

The 2026 World Cup is the greatest architectural experiment in the tournament’s history

.

Mark Gower, Kingston University

The 2026 World Cup is the greatest architectural experiment in the tournament's history

Dallas Stadium is one of 16 venues for the 2026 Fifa World Cup. Jeffrey McWhorter/EPA

When football commentators analyse a World Cup match, they tend to focus on tactics, technical ability, physical conditioning and psychology. If a team wins away from home, we hear about mentality. If a player scores a spectacular goal, we praise their vision or instinct. Yet there is another factor that receives remarkably little attention: the stadium itself.

The 2026 Fifa World Cup, hosted across the United States, Mexico and Canada, presents perhaps the greatest architectural experiment in the tournament’s history. Sixteen stadiums, spread across the three countries, are staging matches in environments that differ dramatically in size, scale, form, lighting conditions and spatial character.

Some are purpose-built football grounds. Others are enormous NFL arenas adapted for the world’s game. Several feature retractable roofs. Others remain open to the elements. Together, they create a fascinating question: can the architecture of a stadium influence player performance?

As an interior designer, I have spent several years researching the relationship between footballers, spatial awareness and stadium design. My research began with a simple observation: across football, teams consistently perform better at home than away.

Traditional explanations focus on crowd support, yet during the COVID pandemic, when matches were played behind closed doors, home advantage did not disappear. This suggests there may be more complex factors at work.

Playing the space

A player receiving a pass rarely begins processing information at the moment the ball arrives. Long before that pass is played, they have already built a mental picture of their surroundings. They understand where they are positioned in relation to the touchline, the penalty area, teammates and opponents. But they also orient themselves through a series of architectural cues embedded within the stadium itself.

These cues can be obvious or subtle. The angle of a stand. The location of a tunnel. The shape of a roof. The position of advertising. The colour surrounding the pitch. The direction of sunlight. The edge of a seating tier. Together, these become reference points that help players orient themselves and make decisions faster.

John Beck, Cambridge City manager in the early 1990s, would set up key markers in each of the four corners of the team’s home ground. The markers would be hoardings printed with the word “quality”. When full backs would receive a ball deep in their own half they would look up and were asked to hit the ball as hard as they could towards the quality signs. These were nicknamed “quality passes”. While quite a primitive tactic, it was effective for Beck; he guided the club to two successive promotions and to two successive quarter-final appearances in the FA Cup.

Mercedes-Benz Stadium in Atlanta, Georgia
Mercedes-Benz Stadium in Atlanta, Georgia is one of the 16 venues for the 2026 World Cup.
Kurtis Toliver/Shutterstock

At the 2026 World Cup, players have encountered some of the most distinctive football environments ever assembled for a single tournament. In Dallas, matches are taking place inside a stadium capable of holding more than 90,000 spectators. For many players, this will be the largest enclosed sporting environment they have ever experienced.

Suspended above the field are giant video screens so large they have become part of the stadium’s identity. Whether consciously or unconsciously, such dominant visual elements contribute to the player’s reading of space.

In Atlanta, a retractable roof and climate-controlled interior create conditions unlike those found in most traditional football grounds. The stadium’s vast pinwheel-esque roof structure and glass end wall produce a highly controlled environment where wind, temperature and external distractions are largely removed.

Mexico City’s Estadio Azteca provides a very different experience. It is one of football’s great cathedrals, steeped in memory and history. Generations of players have competed there, from Pelé in 1970 to Maradona in 1986. Unlike many newer venues, the Azteca was designed specifically for football, creating a spatial relationship between players and spectators that feels fundamentally different from many multipurpose grounds.

Meanwhile, venues such as Vancouver’s BC Place, with its retractable cable-supported roof, or Seattle’s Lumen Field, with its dramatic open end framing the city skyline, create visual identities that players must quickly learn to navigate and interpret.

Estadio Azteca in Mexico City
Estadio Azteca in Mexico City is one of football’s great cathedrals.
Macbeth_GP/Shutterstock

From a football perspective, the challenge is adaptation. The German footballer Thomas Müller once described himself as an “interpreter of space”, a phrase that captures something important about elite performance. Great footballers appear to slow down time. They often know what they are going to do before the ball reaches them. This ability is developed through experience and familiarity.

The more often players operate within a particular environment, the more effectively they build what psychologists call cognitive maps. Over time, the surroundings become familiar and require less conscious processing. This familiarity creates fractions of a second of additional thinking time. At the elite level, those fractions can make the difference between scoring and missing, winning and losing.

The challenge of a World Cup is that players rarely have this luxury. Teams move rapidly between venues. Conditions change from match to match. Architectural cues that were familiar in one stadium disappear in the next. Players must repeatedly rebuild their understanding of space and place. This is why preparation becomes so important.

For decades, coaches have analysed opposition tactics in meticulous detail. Yet comparatively little attention has been paid to preparing players for the architectural characteristics of the stadium itself. Understanding sightlines, lighting conditions, pitch orientation, roof structures and spatial landmarks could offer marginal gains that become decisive in elite competition.

From a design perspective, this raises an equally interesting question. Modern stadiums are increasingly designed around fan experience, hospitality and commercial revenue. Yet the primary performers within these spaces remain the players themselves. If architecture can influence orientation, perception and decision-making, should stadium design place greater emphasis on players? Perhaps this will be the next frontier in sporting performance.The Conversation

Mark Gower, Head of Department of 3D Design, Kingston University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation.

[subscribe2]

.

Strengthen Regional Cooperation on Urban Resilience

Strengthen Regional Cooperation on Urban Resilience

Scenic view of the historic Kasbah in Algiers, capturing the old architecture at sunset with warm tones. by Adem via Pexels

.

Arab States strengthen regional cooperation on urban resilience and risk-informed development

.

UNDRR 30-06-2026

.

Photo of workshop participants with screen presentation
UNDRR ROAS

 

.

Representatives from governments, regional organizations, United Nations agencies, technical institutions and city authorities gathered in Algiers for a three-day regional workshop on urban resilience, smart cities and risk-informed development, reaffirming their commitment to building safer, more resilient and sustainable cities across the Arab States.

Organized alongside the inaugural meeting of the Arab Urban Resilience Committee, the workshop provided a regional platform to exchange knowledge, strengthen institutional coordination, and identify practical approaches for integrating disaster risk reduction into urban planning, governance and investment.

The event was organized by the League of Arab States (LAS), the Arab Centre for the Prevention of Earthquake and Other Natural Disasters (ACPEND), the United Nations Office for Disaster Risk Reduction (UNDRR), UN-Habitat, and regional partners, reflecting a shared commitment to advancing risk-informed urban development in support of the Sendai Framework for Disaster Risk Reduction 2015–2030 and the Sustainable Development Goals.

Advancing risk-informed urban resilience

The workshop focused on translating global commitments into practical action at the national and local levels, emphasizing the need to strengthen governance, improve risk-informed planning, and promote investments that enhance urban resilience.

Participants explored regional priorities for addressing urban risks, integrating disaster risk reduction into urban development policies, strengthening institutional coordination, and reinforcing collaboration between national and local authorities to better anticipate, manage and reduce current and emerging risks.

Discussions also highlighted the growing importance of resilient cities in addressing the interconnected challenges of climate change, rapid urbanization, infrastructure development and disaster risk, while ensuring that resilience is embedded within sustainable development planning.

From commitment to implementation through MCR2030

UNDRR facilitated a dedicated session on the Making Cities Resilient 2030 (MCR2030) initiative, showcasing progress across the Arab region and demonstrating how cities are translating global commitments into concrete local action.

The session highlighted practical tools and approaches for strengthening urban resilience, including the MCR2030 roadmap, the Disaster Resilience Scorecard for Cities, resilience action planning, disaster risk financing, disaster loss and damage data systems, and the Early Warnings for All initiative.

Participants also exchanged experiences from cities including Salalah and Alexandria, illustrating how local leadership, peer learning and partnerships are helping cities move from resilience planning to implementation. The discussion underscored the value of city-to-city cooperation and regional knowledge exchange in accelerating resilience action across the Arab region.

Building greener, smarter and more resilient cities

Participants explored how nature-based solutions, smart city approaches and digital innovation can strengthen resilience while supporting sustainable urban development.

Sessions examined the growing impacts of climate-related hazards, including extreme heat, flooding, drought and environmental degradation and highlighted the importance of resilient infrastructure, integrated urban planning, sustainable finance and community engagement in reducing disaster risk.

The workshop reaffirmed that resilient cities require coordinated action across all levels of government, supported by strong partnerships with academia, the private sector, civil society and local communities.

Strengthening regional cooperation

A key outcome of the meeting was the establishment of the leadership of the Arab Urban Resilience Committee, marking an important step towards strengthening regional cooperation on urban resilience.

Recognizing the leadership demonstrated by the City of Salalah through its engagement in the MCR2030 initiative and its contribution to advancing urban resilience across the region, the Sultanate of Oman was selected to chair the Arab Urban Resilience Committee, with Algeria and the State of Palestine serving as Vice-Chairs. The Committee will provide a regional platform to promote collaboration, facilitate knowledge exchange, and support the implementation of risk-informed urban resilience policies and practices across the Arab States.

The workshop concluded with renewed commitment from participating countries and partners to strengthen regional cooperation, enhance technical exchange, and accelerate the implementation of risk-informed urban development.

By connecting global frameworks with national policies and local action, participants reaffirmed that resilient cities are fundamental to protecting development gains, reducing disaster risk, and advancing sustainable development throughout the Arab States.

.

.

 

[subscribe2]

.

Empower Signs Global Agreement to Expand District Cooling

Empower Signs Global Agreement to Expand District Cooling

A stunning aerial view of Dubai’s modern skyline, showcasing iconic skyscrapers and urban design. by Nelemson G via Pexels

.

Empower signs global agreement to expand district cooling

.

Empower has signed an international agreement to strengthen cooperation and accelerate the adoption of district cooling systems worldwide

.

Highlights by Level 4 AI

Emirates Central Cooling Systems Corporation (Empower) has signed a strategic Memorandum of Understanding aimed at strengthening international cooperation and accelerating the global adoption of district cooling systems.

The agreement was signed by Ahmad Bin Shafar, CEO of Empower and a member of the International District Energy Association Board of Directors, alongside representatives from several countries and international organisations.

The signing took place during the 117th International District Energy Association Conference and Exhibition 2026 in Ottawa, Canada.

The MoU positions district cooling as a practical solution for improving energy efficiency, strengthening energy security, supporting local economies and reducing carbon emissions.

It also seeks to expand the use of district cooling through greater knowledge exchange, innovation and the development of policies and regulatory frameworks that support deployment in cities worldwide.

The signatories committed to supporting the transition towards more sustainable and resilient energy systems and strengthening collaboration across the district energy sector.

The agreement aligns with the objectives of the 2015 Paris Climate Agreement and the climate and sustainability goals of the United Nations Framework Convention on Climate Change.

Empower said the MoU reinforces its role in international initiatives supporting the transition to a low-carbon economy through strategic partnerships and knowledge exchange.

It also strengthens the company’s position as a global district cooling provider and contributor to the development of sustainable urban energy systems.

Bin Shafar said the agreement reflected increasing international recognition of district cooling as an effective climate and energy solution.

“This agreement reflects a growing international commitment to strengthening cooperation and knowledge exchange to accelerate the development and wider adoption of district cooling systems as a practical and effective solution for advancing sustainability, improving energy efficiency and reducing carbon emissions,” he said.

“At Empower, we are proud to represent the UAE in this important initiative, which reflects the country’s leading position in supporting climate solutions and advancing the transition to a low-carbon economy.”

Bin Shafar added that district cooling and district energy would play an important role in creating more efficient, resilient and future-ready cities.

He said stronger international cooperation could help accelerate the development of sustainable urban energy systems while supporting economic growth and improving communities’ resilience to climate change.

Empower participated in the IDEA Conference and Exhibition 2026 as a Diamond Sponsor.

The event was held under the theme “Connecting Networks” from 23 to 26 June.

Empower’s participation included keynote sessions involving Bin Shafar and meetings with senior officials and industry experts.

The discussions focused on opportunities to strengthen international cooperation and share best practices across the district cooling industry.

 

Simone Liedtke

Based in Dubai since 2025, Simone is a seasoned features writer with nearly a decade of experience in technical writing. Previously penning stories for an engineering and a mining magazine in South Africa,…

Read more on , , , .

.

[subscribe2]

.