Tag Archives: urbanization

Urbanization + Climate Emergency = Massive Problems. Let’s talk solutions

Urbanization is the tendency for sizable numbers of people to move out of rural areas and congregate in cities. This phenomenon happens in large part because cities tend to offer people more amenities and economic advantages than rural areas do.

Urbanization, overall, brings many benefits – but it does also pose some problems that need solving. For starters, the climate crisis disproportionately affects urban areas, and the urban heat island effect can raise urban temperatures by several degrees. So what can we do?

Image credits: Umet Ale.

It isn’t exactly news that rapid urbanization increases climate risk for billions of people; back in 2017, researchers at the United Nations (UN) warned us that this would be a problem. As it turns out, they were correct — since that prediction was originally published, we’ve witnessed extreme impacts such as severely flooded cities and cities that are literally sinking under their own weight.

A growing mountain of scientific evidence is showing that immediate action is needed to resolve the problems posed by the dangerous combination of urbanization and climate emergency.

Recent research suggests that low-carbon cities have the potential to mitigate environmental threats. The researchers have proposed four solutions for achieving these low-carbon cities:

1. Minimize the Footprint of Each City

 The researchers at the Chinese Academy of Sciences utilized data from nineteen counties in Taiwan. They employed partial least squares (PLS) modeling methods as a means for identifying the most important factors that affected carbon emissions in the counties of interest. 

To build their model, the researchers used data describing the size and density of each city, the currently existing land mix, the amount of urban sprawl, the level of industrial usage in each city, and the balance between housing and employment. They concluded that there were multiple factors that needed to be minimized in order for cities to enjoy a corresponding reduction in carbon emissions:

  • City size
  • Urban sprawl
  • Industrial usage
  • Transportation

2. Maximize Green Urban Spaces, Land Mix and Urban Density

 The model also suggested several factors that should be maximized:

  • Green urban spaces
  • Land mix
  • City density 

These findings corroborate previous research. We already learned that trees can help to cool down cities — and that every tree in an urban environment counts. So here we have further confirmation of the importance of green coverage in urban areas.

3. Focus on Urban Transportation Systems

 The researchers suggested “transit-oriented development” as a possible solution for reducing carbon emissions.

Image credits: Fraser Cottrell.

What, exactly, is transit-oriented development? The US Department of Transportation (DOT) website gives us an overview: It’s a situation where a transit system connects a community of people to nearby amenities including entertainment venues, commercial spaces, office buildings and residences. The closer together these accommodations are, the greater the potential is for the reduction of carbon emissions. The ideal is “walkable” cities where people can walk to work, stores, and many of the services they need.

Experts at the DOT point out that transit-oriented development is most likely to happen when governments make policies that encourage it. Tools they can utilize for this purpose include land use planning and zoning laws.

4. Engage in Conscious Urban Planning

Image credits: Srecko Skrobic.

None of the above-mentioned solutions will happen unless leaders step up to actively take charge of managing the urbanization process. The researchers summarize their findings by reporting that “appropriate urban policies and planning, such as compact cities, green cities, or transit-oriented development, might lower carbon emissions and thus further serve as useful strategies for building low-carbon cities.”

As things currently are, much of the world’s urbanization is happening haphazardly. It is true that some cities are employing urban and regional planners in hopes of making responsible use of their region’s resources; however, urban planning isn’t a universal priority across the globe. We need to reevaluate our priorities with the goal of actively managing our urban growth rather than allowing it to happen carelessly.

Other experts have weighed in on the issues independent of this research to express opinions that corroborate the findings presented in the summary. In an article posted at Urban.com.au, Professors Gabriela Quintana Vigiola and Heather MacDonald of the University of Technology Sydney’s Master of Urban Planning program point out that urban and regional planners are one critical key to solving the double-whammy problems of “climate change and limited resources” that disproportionately affect urban areas.

Professor Boyd Cohen of the EADA Business School in Barcelona, Spain also concurs. According to Cohen, urban planning appears to be the single most important means available to us for reducing fossil fuel pollution and consumption. He also points out that technology and clean energy for transportation have important roles to play in solving the problems caused by climate change and urbanization.

While the proposed solutions are likely to be viable ones, it will take a collaborative effort between governments and the public to actually implement them.

The paper “Crucial factors of the built environment for mitigating carbon emissions” will be published in the February 2022 edition of the journal Science of the Total Environment.

Children in greener urban areas have a higher IQ and fewer behavioral issues

Children living in urban areas with a higher percentage of green space have higher intelligence and fewer behavioral problems, according to a new study. The findings bring yet another piece of evidence regarding the importance of green areas for children’s cognitive development.

Credit Jay Hsu. Flickr (CC BY-NC-ND 2.0)

A group of researchers from Belgium assessed the intelligence of over 600 children between 7 and 15 years old. They found that a 3% rise in the greenness of their neighborhood increased IQ score by an average of 2.6 points, an effect noticed both in rich and poor areas of Belgium.

“There is more and more evidence that green surroundings are associated with our cognitive function, such as memory skills and attention,” Tim Nawrot, a professor at Hasselt University in Belgium, where the study was conducted, told The Guardian.

“What this study adds with IQ is a harder, well-established clinical measure.”

The researchers used satellite images to check the level of greenness in the neighborhoods where participants lived. They reviewed parks, gardens, street trees, and all other types of vegetation. The average IQ score of the children was 105, with 4% of them with a score below 80 having grown up in areas with low levels of green areas.

None of the children had an IQ score below 80 in areas with a high amount of green space. Nevertheless, the benefits seen from greenery in urban areas weren’t replicated in suburban or rural areas. This might have been due to those places having enough greenness for everyone living there to benefit from, Nawrot said.

The researchers also measured behavioral difficulties in children such as aggressiveness and poor attention, using a standard rating scale. The average score was 46, with a 3% increase in greenery leading to a two-point drop in behavioral problems, agreeing with the findings of previous studies.

“I’m always wary of the term intelligence as it has a problematic history and unfortunate associations,” Mathew White, an environmental psychologist from Exeter University, not related to the study, told The Guardian.

“But, if anything, this study might help us move away from seeing intelligence as innate – it could be influenced by the environment, and I think that is much healthier.”

The researchers argue this is the first study investigating the association between residential green space and intelligence in children. Previous studies have already shown that urban green space is important for cognitive development in children by improving working memory, attention, and school performance.

The results provide important policy and public health implications. Whereas in 1950, only 30% of the world’s population lived in urban areas, more than half of the global population today lives in cities. This is expected to increase to 68% by 2050.

Residents of urban areas often have limited access to natural environments in their daily lives. That’s why understanding the health disparities that exist between urban and rural environments is essential for maintaining and improving human well-being in a rapidly urbanizing world, according to the researchers.

The study had a set of limitations. Surrounding green space was assessed based on residential location; however, no information on school location was available. No information was available on time-activity patterns, such as time spent outdoors, and on possible mediators between green space and intelligence.

The study was published in the journal PLOS Medicine.

City frogs are more attractive than their countriside cousins, new study shows

Living by the forest may be romantic, but living in a city makes you more attractive to the opposite sex — if you are a túngara frog, at least.

A calling male túngara frog with a large inflated vocal sac. Image credits: Adam Dunn.

Increasingly, recent studies have shown significant differences between urban animals and rural-dwelling creatures from the same species — and this makes a lot of sense. Mankind is causing dramatic changes over a wide range of environments and many creatures are slowly adapting to urban conditions. Just recently, researchers found that some urban spiders are no longer afraid of lights; now, a new study reports that city life makes male frogs more attractive.

The authors, led by Wouter Halfwerk from the Vrije Universiteit Amsterdam, compared the ‘chuck’ calls of frogs living in both urban areas and forests near the Panama Canal.

Previous research had found that creatures, such as birds, frogs, and grasshoppers sing or call differently in noisy urban areas, but it was unclear what the effects of these changes are.

“Urbanization can cause species to adjust their sexual displays, because the effectiveness of mating signals is influenced by environmental conditions,” researchers write in the study. “Despite many examples that show that mating signals in urban conditions differ from those in rural conditions, we do not know whether these differences provide a combined reproductive and survival benefit.”

Now, researchers found that urban frogs “sing” more often and use more complex calls than their rural counterparts. They then recorded these calls and played them back to female túngara frogs in the lab. They found that 75% of the females were more attracted to the more complex urban calls.

It’s not exactly clear why this happens, though researchers suspect it has a lot to with how safe the environment is. While calling out can help you get a mate, it can also draw in predators. Since cities generally have far fewer predators, frogs are free to let ‘er rip.

“It definitely shows that if you change the abundance of predators, parasites and mates, that induces a strong evolutionary response,” says Halfwerk.

However, city environments are also more fragmented, which means it’s more difficult to find a mate. So it’s possible that frogs developed their calls because they have to signal more often.

“It is harder for males to get mates in the city and so that is why they even have to work harder than their forest counterparts to get the females,” said Halfwerk.

The team now aims to carry out genetic studies, as well as a large-scale breeding project, to see how these characteristics are passed down through the generations.

However, an important takeaway is that human activity is rapidly changing natural habitats. Creatures are forced to adapt — and sometimes, some of them are very successful, but unfortunately, other times they are not — so urbanization has clearly become a strong selective agent.

The study was published in Nature Ecology and Evolution.


LED light savings backfire spectacularly as light pollution increases dramatically

LEDs promised to bring a revolution in outdoor lighting and in a way, they did. It just might not be what we were hoping for.

Light pollution is almost ubiquitously associated with urbanization. Image credits: Wonderlane / Flickr.

When solid-state lighting options such as LEDs, OLEDs, and PLEDs were introduced, everyone hoped that they would reduce costs, energy usage, and the environmental impact of outdoor lighting. After all, these new systems consumed less and often have a longer lifespan than their conventional counterparts. But a new study has found that due to these reduced costs, many municipalities are actually using more and more lighting, creating a net effect that’s even worse than before. Not only are some places consuming more energy overall, but they are producing much more light, with potentially dramatic consequences on wildlife and our own health.

Better isn’t always better

Instead of reaping the benefits of lower costs, many municipalities recklessly took advantage of the new technology and installed more and more lighting posts, resulting in using even more energy than before.

“As a result, the world has experienced widespread ‘loss of the night,’ with half of Europe and a quarter of North America experiencing substantially modified light-dark cycles,” write the researchers in the new study, which was published today in Scientific Advances.

This growth is tightly correlated with the increase of the Gross Domestic Product (GDP), and the fastest growth occurred in developing countries. However, developed areas also tended to show an increase in light production.

“What’s more, we actually see only part of the light increase”, says Christopher Kyba whose research is done both at GFZ and the Leibniz Institute for Freshwater Ecology and Fisheries IGB.

What Kyba is alluding to is the fact researchers were expecting the measured light to go down dramatically, because the Day-Night-Band instrument which was used to gather the data doesn’t see wavelengths below 500 nanometers (human visible range is between 400 and 700 nm). LEDs output much more light below the 500 nm threshold than regular light bulbs, so even if light consumption remained the same, researchers were expecting to measure an overall luminosity, due to the measuring limitation. But they didn’t. If anything, they reported more luminosity than ever in many parts of the world.

“For that reason I expected that wealthy countries would appear to be getting darker (even if that wasn’t truly the case). Instead, we observed wealthy countries staying constant, or in many cases increasing,” Kyba told Gizmodo. “That means that even though some cities are saving energy by switching to LEDs, other places are getting brighter by installing new or brighter lamps (that need new energy). So the data aren’t consistent with the hypothesis that on the global scale, LEDs are saving energy for outdoor lighting applications.”

More light, more problems

Photograph of Calgary, Alberta, Canada, taken from the International Space Station on Nov. 27, 2015. Many areas on the outskirts are newly lit compared to 2010, and many neighborhoods have switched from orange sodium lamps to white LED lamps. Credits: NASA’s Earth Observatory/Kyba, GFZ.

Artificial light is, of course, crucial to modern society. It allows us to work at any time or in naturally dark environments and it offers possibilities for recreation and sports — it allows us to do what we want when we want it, no longer depending on the Sun’s natural cycle. However, too much light can be a bad thing, with several studies accusing it of compromising health and disrupting ecosystems.

In 2007, “shift work that involves circadian disruption” was listed as a probable carcinogen by the World Health Organization’s International Agency for Research on Cancer. Another recent study by Professor Steven Lockley at Harvard Medical School found that artificial light, even dimmed, can have significant effects on sleep disruption and melatonin suppression. Light pollution also poses a serious threat to wildlife — particularly to nocturnal wildlife. Despite all these warning signs, not much action has been taken to limit light pollution, and as urbanization spreads more and more, so too does light pollution.

Still, there are reasons to be optimistic. Unlike other types of pollution, light doesn’t require any dramatic action to reverse its effects. All you do is switch it off, and it’s gone (unlike say oil pollution, where even if you stop the pollution source, you still need to clean up the existing mess). Also, some places were less careless than others. Light emission per capita in Germany is three times lower than in the US, while the standard of living is just as much, if not significantly higher. This gives hope that prosperity doesn’t always mean going over the top with resource consumption, and a reasonable energy consumption (along with a reduction of light pollution) can be achieved — but only with responsible policies. Perhaps it’s time for such policies to emerge at a local, national, and even international level.

The study has been published in Science Advances.

Watch 6,000 Years of Urbanization in 3 Minutes

A new study from Yale University mapped urban centers from 3700 B.C. to 2000 A.D. Now, Max Galka at Metrocosm has created a fun video using that geocoded data set. You can see the video below:

In the Yale-led paper, published in Scientific Data, the authors wrote about the significance of their work:

“Whether it is for timely response to catastrophes, the delivery of disaster relief, assessing human impacts on the environment, or estimating populations vulnerable to hazards, it is essential to know where people and cities are geographically distributed. Additionally, the ability to geolocate the size and location of human populations over time helps us understand the evolving characteristics of the human species, especially human interactions with the environment.”

The video is also very nifty, as it allows us to easily visualize how cities came to be and grew. In an email, Galka told City Lab why he created this video, and what he found interesting about it:

“Most datasets available go back only a few years or decades at most. This is the first one I’ve seen that covers 6 millennia. I’m a big fan of history, so after reading the study, I thought it would be interesting to visualize the data and see if it offers some perspective… . What I found most surprising was how early some of the MesoAmerican cities formed, several hundred years before the first cities in Europe.”