Urban Update 17 October 2024

Energy and Climate Change


Urban areas found to intensify summer storms  >>>>
Urban areas are thought to bring about higher rainfall because of:

  1. The Urban Heat Island effect – with the increased temperature destabilizing the atmospheric boundary layer, mixing air of different temperatures and humidity levels.  Increased surface temperatures within the city leads to increased vertical mixing.
  2. Surface roughness – which slows the prevailing wind and forces it upwards
  3. Urban aerosols (such as pollution from burning fossil fuels)

The atmospheric boundary layer (also called the “Planetary Boundary Layer) is the name given to the first layer of air above the earth’s surface.    

The results of this study show that urban areas act to intensify rainfall—mostly over them, but sometimes on their peripheries, with larger cities tending to have larger rainfall increases.  The effect is strongest in the afternoon and evening.
 
Comparison of four different urban climate models - Urban Climate
To understand how to make towns and cities resistant to climate change, including reducing the urban heat island effect, requires an understanding of the influences on the local climate of individual towns and cities.  This study compares the accuracy of four different models in estimating night-time temperatures.  Night-time temperatures are of special importance, as people are generally unable to avoid them.  Tropical nights where the temperature doesn’t fall below 20 centigrade are becoming more common place.  In 2023 a nighttime temperature of 37.4 °C was recorded in Spain.  Humans have a body temperature of around 36.5–37.5 °C. 
 
Burning household waste now UK’s most carbon intensive form of power >>>>

 

Movement

 
Greening urban mobility: Assessing environmental and functional characteristics of bicycle infrastructure in the post-pandemic Era - Habitat International
This study used a sought to find the best bike lane design, including an assessment method and a pilot study in Palermo, Italy.  It found that separated bike lanes were preferred.
 
Long-term validation of inner-urban mobility metrics derived from Twitter/X - Environment and Planning B: Urban Analytics and City Science
For a while Twitter data has been used as a proxy for mobility patterns, however there is little research on its reliability and whether it represents the population as a whole, particularly on a small spatial scale where Twitter data may be extremely sparse.  This paper highlights the need for caution when using Twitter for short-term modelling of urban mobility flows.
There may be further challenges outside the study period owing to the decline in use of Twitter/X and a shift in the sort of person using it.  Political alignment has changed, younger audiences have moved away from Twitter/X to TikTok, and the gender balance has widened, with Twitter/X becoming increasingly male dominated circa 69% male to 31% female. 

The big problem millions of drivers have with car headlights and what's now being done about it >>>>
Vehicle headlights have got brighter, dazzlingly so, as technology has transitioned from conventional tungsten bulbs, halogen bulbs in the 19760s and 70s, xenon and argon bulbs, gas discharge and latterly LED bulbs. The current generation is perhaps four times brighter than the earlier generations, raising concerns about danger from overbrightness, dazzling from mis-aligned bulbs and an erosion of road safety.
 

20mph limits

The speed limit debate continues….
 
England:  Oswestry Town Council pushes for extended 20mph zone >>>>
 
Wales: media controversy continues >>>>
Transport for Wales found that from September, 2023, to April, 2024, average vehicle speeds on main 20mph roads dropped by around 4.3mph;  Average journey times have increased on most assessed routes but generally not by more than two minutes; journey time variability decreased on most routes, suggesting improved journey time reliability.  There were no changes in air quality.
The media however continues to promote a controversial take on the introduction of the 20mph default limit, presenting the views of aggrieved drivers, and ignoring non-drivers, despite the fact that they make up around 40 percent of the population.

This article quotes statements made on social media, including a driver complaining that 20mph limits are causing him to have to change gear more often and that it is damaging his ankle joints.   Another complains of “anger and frustration”... “which in turn leads to other very serious social and health problems."  It is not clear what those very serious social and health problems are, but its presumably some sort of Star Wars reference…. frustration leads to anger, anger leads to hate, and hate leads to the dark side?

 

Low Traffic Neighbourhoods

 
Petition launched against proposal to scrap Low Traffic Neighbourhoods in Tower Hamlets
https://you.38degrees.org.uk/petitions/protect-our-safer-streets-in-tower-hamlets
 

Natural Environment 


Raft based eco-system introduced in river >>>>
 
Autumn flowering plants introduced into urban areas boost wild and honeybees >>>>
 
Study shows neonicotinoids are harmful to birds on all fronts >>>>
 
Airborne plasticisers found in coastal California >>>>
As plastic decays, plasticisers are released into the environment.
“The only way to decrease the concentration of plasticizers in the air is to decrease our production and consumption of materials containing plasticizers,”
 
Microplastics found in dolphin breath for first time – study >>>>
This is one of the most unlikely group of animals to be expected to be affected by microplastics

 

Humans, Health, Society


The relentless push for productivity misconstrues how our brains work >>>>
This article in the New Scientist suggests that a structure in our brains point to three modes of thinking:
Gear 1, the mind can wander freely;
Gear 2, we are highly engaged and attentive;
Gear 3, we are hyperalert and quick to respond to a crisis.
 
Unhoused people at substantially increased risk from heat waves >>>>
Study reports that deaths among unhoused people in two major West Coast cities were 10 to 100 times greater than heat-attributable deaths among the general population
 
Association between the urban neighbourhood built and social environment characteristics with physical functioning among mid- and older-aged adults: A systematic review - Social Science & Medicine
There is increasing awareness of how neighbourhood factors impact individual health, especially among adults aged 45 and older.  This review of 25 cross-sectional and longitudinal studies, examined how urban neighbourhood characteristics—both built (infrastructure) and social (community interactions)—affect physical functioning in mid-to older-aged adults. 

It assessed 13 different characteristics and found that 6 had an impact:

  • land use mix and destinations,
  • walkability, and
  • crime safety,
  • greenness and parks,
  • social environment,
  • neighbourhood disadvantage,

There was weaker evidence for:

  • aesthetics
  • residential density,

 

Politics, Philosophy, Economics

 
How to distinguish climate sceptics, antivaxxers, and persistent sceptics .>>>>
This study identifies two types: single-issue sceptics and double sceptics.

  • Single-issue sceptics distrust scientists but may be persuadable.
  • Double sceptics distrust all institutions and are harder to change.

The research found higher scepticism among men, right-wing individuals, and those prioritizing the economy.
Scepticism is inversely related to education and science knowledge.

The study included surveys from eight countries, and found that double sceptics are a small minority.  It suggests that efforts should focus on specific scepticism rather than treating all sceptics as conspiracists.
 
Is Australia's urban-regional schism on climate reality or rhetoric? - Journal of Rural Studies
This study uses a quantitative survey of 2952 Australians to compare differences in opinion on climate and social issues across residents in rural and urban areas.

The study found that the only noticeable urban-regional difference was for the statement “City people and country people are more different to each other than they are similar”, with those in inner and outer regional areas more likely to agree with this than those in major cities.  It found instead that “progressive-conservative political ideology, and frequency of consuming ABC and Sky News were the most consistently significant variables predicting climate opinion”.  It suggests that what matters more may in effect be whether someone identifies with “rurality”.

The study concludes that “the rhetoric of the urban-regional schism is likely less about climate change as a policy issue, and more about cultivating a social division that may reap political benefits, particularly for those with interests threatened by the emergence of a broad base of social support for change to the status quo”.  

 
Call for young Scots to have legal right to live where they grew up >>>>
 

History


The Urban Layout, Buildings and Baths Uncovered in the Ancient Vacceo-Roman City of Saldania in Spain >>>>

 

Built Environment 

 
Impact of urban green spaces on air quality: A study of PM10 reduction across diverse climates - Science of The Total Environment
The findings of this paper show increasing PM10 with less than 20 % green space. This warrants further investigation and might also hint at the fact that other land uses rather than green spaces contribute to higher particulate matter concentration.  The model used by the researchers suggest that at least a land use of at least 27 % green space is needed to significantly reduce the particulate matter flux.
 
To counter climate change, Colombian cities weave nature back into their urban fabric >>>>
 
Unlocking neighbourhood density - Journal of Urban Economics
This study uses detailed geo-spatial data and socio-economic observations from Norway to create a comprehensive dataset, focusing on building heights at a very local level (10m x 10m). The research examines urban density (the ratio of population to unit of land area)  by breaking it down into three main components:

  1. crowding, (defined as the number of people per square metre of floor area)
  2. building height, and
  3. residential coverage.

It finds that the typical decrease in density as one moves away from the city centre is mainly influenced by building heights. There is also evidence suggesting a trade-off between the size of apartments and yard space.

The study also reveals that higher urban density is associated with lower income and greater income inequality in neighbourhoods (in Norway). This contradicts previous research that often shows a positive correlation between density and wages due to labour market factors.
 
What the paper does illustrate is the difficulty we have over defining and measuring density, and points to a lack of a common and robust understanding. Governments often use dwellings per hectare as a measure, yet a dwelling can be a bedsit, a three bedroom house with parking for two cars, a palace, or shared housing.  It is baffling that we cannot resolve this most basic of measures, or even establish a clear purpose.
 
Can regionalization enhance the performance of land-use change models in rapidly urbanizing areas? - Environment and Planning B: Urban Analytics and City Science
This paper looks at the potential for sub-regional land-use change drivers in creating more accurate and useful land use change models.  

Urban Sprawl and Routing: A Comparative Study on 156 European Cities - Landscape and Urban Planning
This paper examines the effect of urban sprawl on the efficiency of car and bicycle routes across European cities.  It comes from a mathematically-based perspective, and is a difficult read. It finds that compact cities make for efficient transportation routes.

It also observes that sprawl is higher in Central and North-Western Europe compared with Southern and Eastern Europe, and Spain in particular. It suggests that this is due in part to economic disparity leading to “diverging car ownership rates, access to detached housing, infrastructure development, and investments in public transportation”.

It finds a significant correlation between five sprawl indicators and both travel distances and routes by car and bicycle: transportation is inherently less efficient in cities with higher levels of sprawl states the paper.

The five sprawl indicators used were

  • Land usage - Estimation of residential land use
  • Gini coefficient - (this is somewhat confusing as the Gini Coefficient is commonly defined as term from economics: a measure of income inequality and nothing to do with sprawl)
  • Shannon entropy - Uncertainty in the population distribution
  • Moran I index - Degree of spatial clustering
  • Bribiesca index - Compactness of the city shape (unfortunately we couldn’t find a definition in any other papers on the internet)

 
10 abandoned cities with eerily beautiful ghost town architecture >>>>
 

England

 
Government housing targets unrealistic and unfair, English councils warn >>>>
 
English homes ‘face decades of high bills and emissions’ without urgent action from ministers >>>>
 
First look at planned obelisk on Oxfordshire housing estate >>>>
 
Sherford's 'Urban Quarter' is growing every day >>>>
Unfortunately the development still lacks shops.  At the moment it comprises housing, a school, and hoardings with pictures of shops.  

One man's campaign against his 'anti-fun' city by placing official looking signs with a humorous twist >>>>