More people are cycling in Britain’s major cities – except two

An exciting new form of bike being tested in Birmingham, 1935. It did not catch on. Image: Hulton Archive/Getty.

The latest instalment of our series, in which we use the Centre for Cities’ data tools to crunch some of the numbers on Britain’s cities. 

Round here, we are broadly speaking in favour of making cities more liveable, and broadly speaking against filling them with horrible, choking, lifespan-cutting gases like Nitrogen Dioxide. So, on balance, we’re pro-cycling.

It’s reassuring, then, that between the last two censuses, the number of people commuting by bike climbed in most of Britain’s major cities. It’s less reassuring, however, that we’re starting from such a low-base – and also that we have to say “most”, rather than “all”.

But we’ll get to that: first, define your cities. There are 63 cities in the Centre for Cities database – but this includes such metropolises as Blackpool and Aldershot. To make the dataset more user-friendly, we’ve decided to create a new category of “major cities”: London; the 10 cities in the “Core Cities” group; plus the other two national capitals, Edinburgh and Belfast.

Here’s how the percentage of people commuting by bike in those 13 cities changed between the 2001 and 2011 censuses.

The first thing to note is how low the numbers here are: in every city, it’s a tiny minority of people who use pedal power to get to work. Boo.

Within that, though, there’s a pretty clear division between cities where the figures are low, and those where they are really low. In eight of them, they’re jostling around the 1-2 per cent mark. But four cities – Nottingham, Cardiff, Edinburgh and Belfast - are rather higher (3-6 per cent, say) suggesting that they’re more cycling friendly.

Mathematicians among you will have noticed that’s only 12 cities. The 13th is London, which saw a quite significant increase between the two censuses. In 2001, just 2.3 per cent of Londoners cycled to work, placing it just above the low-cycling group; a decade later, that number had jumped to 3.6, putting it securely in the higher-cycling one. Those numbers are still small, and anecdote isn’t data of course, but experience of the capital’s streets suggests to me it will have climbed further in the mean time.

Another city has seen an even more marked increase, and from a higher starting point. That’s Bristol, right at the top of the chart, up from 3.9 to 6.1 per cent. It’s tempting to credit this to the London-ification of the city, as creative hipster types have been forced out of the capital by house prices – but since nearly 4 per cent of Bristolians were already cycling in 2001 it’s probably it’s just a relatively good city for cycling. Good for Bristol.


Anyway. The general story here is of steady increases: in 11 of the cities, more people commuted by bike in 2011 than a decade earlier. The trend is very clearly towards more cycling.

In the last two, however, that number has fallen. In Birmingham it’s fallen very slightly from 1.65 to 1.53 per cent; in Nottingham, very slightly more, from 3.58 to 3.27 per cent.

These are small changes, of course: the larger fall is of 0.3 per cent. Big woop. But it is striking that they go against a trend towards more cycling, and it’s not immediately obvious why that should be.

That said, the trend in the two cities does appear to be different. Over the same period, Nottingham has seen a slightly increase in the proportion of workers commuting by public transport (0.4 per cent) and a slightly bigger fall in those driving (1.25 per cent). So even though cycling numbers are slightly down, the trend is still towards a less car-based city.

My instinct was to credit all this to Nottingham’s tram network – but Bimingham also has one of those, and there things have gone, slightly, in the other direction. Car use is up (0.6 per cent); public transport use is down (0.3 per cent).

These are still, remember, tiny figures: proper margin of error stuff. But nonetheless, at a time when the trend is towards less car-based cities, even standing still looks bad.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

Want more of this stuff? Follow CityMetric on Twitter or Facebook

 
 
 
 

The risk of ‘cascading’ natural disasters is rising

A man watches wildfires in California, 2013. Image: Getty.

In a warming world, the dangers from natural disasters are changing. In a recent commentary, we identified a number of costly and deadly catastrophes that point to an increase in the risk of “cascading” events – ones that intensify the impacts of natural hazards and turn them into disasters.

Multiple hazardous events are considered cascading when they act as a series of toppling dominoes, such as flooding and landslides that occur after rain over wildfires. Cascading events may begin in small areas but can intensify and spread to influence larger areas.

This rising risk means decision-makers, urban planners and risk analysts, civil engineers like us and other stakeholders need to invest more time and effort in tracking connections between natural hazards, including hurricanes, wildfires, extreme rainfall, snowmelt, debris flow, and drought, under a changing climate.

Cascading disasters

Since 1980 to January 2018, natural disasters caused an inflation-adjusted $1,537.4bn in damages in the United States.

The loss of life in that period – nearly 10,000 deaths – has been mounting as well. The United States has seen more billion-dollar natural disaster events recently than ever before, with climate models projecting an increase in intensity and frequency of these events in the future. In 2017 alone, natural disasters resulted in $306bn losses, setting the costliest disaster year on record.

We decided it was important to better understand cascading and compound disasters because the impacts of climate change can often lead to coupled events instead of isolated ones. The United Nations Office for Disaster Risk Reduction, or UNISDR, claims: “Any disaster entails a potentially compounding process, whereby one event precipitates another.”

For example, deforestation and flooding often occur together. When vegetation is removed, top soil washes away and the earth is incapable of absorbing rainfall. The 2004 Haiti flood that killed more than 800 people and left many missing is an example of this type of cascading event. The citizens of the poverty-stricken country destroyed more than 98 per cent of its forests to provide charcoal for cooking. When Tropical Storm Jeanne hit, there was no way for the soil to absorb the rainfall. To further complicate existing issues, trees excrete water vapor into the air, and so a sparser tree cover often yields less rain. As a result, the water table may drop, making farming, which is the backbone of Haiti’s economy, more challenging.


Rising risk from climate change

Coupled weather events are becoming more common and severe as the earth warms. Droughts and heatwaves are a coupled result of global warming. As droughts lead to dry soils, the surface warms since the sun’s heat cannot be released as evaporation. In the United States, week-long heatwaves that occur simultaneously with periods of drought are twice as likely to happen now as in the 1970s.

Also, the severity of these cascading weather events worsens in a warming world. Drought-stricken areas become more vulnerable to wildfires. And snow and ice are melting earlier, which is altering the timing of runoff. This has a direct relationship with the fact that the fire season across the globe has extended by 20 per cent since the 1980s. Earlier snowmelt increases the chance of low flows in the dry season and can make forests and vegetation more vulnerable to fires.

These links spread further as wildfires occur at elevations never imagined before. As fires destroy the forest canopy on high mountain ranges, the way snow accumulates is altered. Snow melts faster since soot deposited on the snow absorbs heat. Similarly, as drought dust is released, snow melts at a higher rate as has been seen in the Upper Colorado River Basin.

Fluctuations in temperature and other climatic patterns can harm or challenge the already crumbling infrastructure in the United States: the average age of the nation’s dams and levees is over 50 years. The deisgn of these aging systems did not account for the effects of cascading events and changes in the patterns of extreme events due to climate change. What might normally be a minor event can become a major cause for concern such as when an unexpected amount of melt water triggers debris flows over burned land.

There are several other examples of cascading disasters. In July, a deadly wildfire raged through Athens killing 99 people. During the same month on the other side of the world in Mendocino, California, more than 1,800 square kilometers were scorched. For scale, this area is larger than the entire city of Los Angeles.

When landscapes are charred during wildfires, they become more vulnerable to landslides and flooding. In January of this year, a debris flow event in Montecito, California killed 21 people and injured more than 160. Just one month before the landslide, the soil on the town’s steep slopes were destabilised in a wildfire. After a storm brought torrential downpours, a 5-meter high wave of mud, tree branches and boulders swept down the slopes and into people’s homes.

Hurricanes also can trigger cascading hazards over large areas. For example, significant damages to trees and loss of vegetation due to a hurricane increase the chance of landslides and flooding, as reported in Japan in 2004.

Future steps

Most research and practical risk studies focus on estimating the likelihood of different individual extreme events such as hurricanes, floods and droughts. It is often difficult to describe the risk of interconnected events especially when the events are not physically dependent. For example, two physically independent events, such as wildfire and next season’s rainfall, are related only by how fire later raises the chances of landslide and flooding.

As civil engineers, we see a need to be able to better understand the overall severity of these cascading disasters and their impacts on communities and the built environment. The need is more pronounced considering the fact that much of the nation’s critical infrastructure is aged and currently operate under rather marginal conditions.

A first step in solving the problem is gaining a better understanding of how severe these cascading events can be and the relationship each occurrence has with one another. We also need reliable methods for risk assessment. And a universal framework for addressing cascading disasters still needs to be developed.

A global system that can predict the interactions between natural and built environments could save millions of lives and billions of dollars. Most importantly, community outreach and public education must be prioritised, to raise awareness of the potential risks cascading hazards can cause.

The Conversation

Farshid Vahedifard, CEE Advisory Board Endowed Professor and Associate Professor of Civil and Environmental Engineering, Mississippi State University and Amir AghaKouchak, Associate Professor of Civil & Environmental Engineering, University of California, Irvine.

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