The problem of space: why Elon Musk doesn't understand urban geometry

Elon Musk unveils the new Tesla Model X Crossover SUV in Fremont, California, last September. Image: Getty.

He may be a brilliant visionary in all kinds of ways, but Elon Musk’s “Master Plan, Part Deux” makes grand plans for the abolition of fixed route public transport without thinking clearly about urban space:

“With the advent of autonomy, it will probably make sense to shrink the size of buses and transition the role of bus driver to that of fleet manager. Traffic congestion would improve due to increased passenger areal density by eliminating the center aisle and putting seats where there are currently entryways, and matching acceleration and braking to other vehicles, thus avoiding the inertial impedance to smooth traffic flow of traditional heavy buses.

“It would also take people all the way to their destination. Fixed summon buttons at existing bus stops would serve those who don’t have a phone. Design accommodates wheelchairs, strollers and bikes.”

Musk assumes that public transit is an engineering problem, about vehicle design and technology.  In fact, providing cost-effective and liberating transportation in cities requires solving a geometry problem, and he’s not even seeing it.  What’s more, he’s repeating a very common delusion, one I hear all the time in urbanist and technology circles.

Musk’s vision is fine for low-density outer suburbia and rural areas.  But when we get to dense cities, where big transit vehicles are carrying huge ridership, Musk’s vision is a disaster.  That’s because it takes lots of people out of big transit vehicles and puts them into small ones, which increases the total number of vehicles on the road at any time.  The technical measure of this is Vehicle Miles (or KM) Travelled (VMT).

Today, increasing VMT would mean increased emissions and increased road carnage. But let’s say technology has solved those problems, with electric vehicles and automation.  Those are engineering problems.  Inventors can work on those.

There is still, and will always be, the problem of space. Increasing VMT means that you are taking more space to move the same number of people. This may be fine in low-density and rural areas, where there’s lots of space per person.  But a city, by definition, has little space per person, so the efficient use of space is the core problem of urban transportation.

The tyranny of maths

When we are talking about space, we are talking about geometry, not engineering, and technology never changes geometry.  You must solve a problem spatially before you have really solved it.

The reigning fantasy of Musk’s argument is that we must always “take people all the way to their destination”. But to do this we must abolish the need to ever change vehicles – from a train to a bus, from a car to a train, from a bus to a bike – and of course we also abolish walking.  This implies a vision in which buses are shrunk into something like taxis, because a vehicle going directly from your exact origin to your exact destination at your chosen time won’t be useful to many people other than you.

So a bus with 60 people on it today is blown apart into, what, little driverless vans with an average of three each, a 20-fold increase in the number of vehicles?  It doesn’t matter if they’re electric or driverless.  Where will they all fit in the urban street?  And when they take over, what room will be left for wider sidewalks, bike lanes, pocket parks, or indeed anything but a vast river of vehicles?

There are audiences for which Musk’s vision makes mathematical sense sense: people for whom useful high-ridership transit isn’t an option anyway.  There are two big categories of these people:

  • People who live in outer-suburban and rural areas, where space is abundant and high-ridership transit isn’t viable;
  • The top 20 per cent or so of urban residents, who can afford to use relatively expensive servies that would never scale to the entire population of the city.

If you are in one of these categories, your most urgent task is to remember that most people aren’t like you, and that cities are impossible if everyone lives according to your personal tastes.  As Edward Glaser said, “one’s own tastes are rarely a sound basis for public policy”.

That issue, right there, is the great disconnect between tech marketing and genuine urban problem-solving.


Tech marketing is all about appealing to elite personal tastes.  It runs on the assumption that whatever we sell to the wealthy today we can sell to the masses tomorrow.  

But some things stop working when everybody buys them. Cars in dense cities, for example, are not a problem when only the top 20 per cent are using them; it’s mass adoption of cars that makes them ruinous to a dense city and to the liberty of its citizens. Ask anyone in a fast-growing developing world city about that.

Here is the harm that this all this elite chatter about abolishing the bus is doing: it’s introducing fatal confusion into the discussion of urban development.

The density solution

Dense cities that want to live in the real world of space and time, and that do not want to become dystopias that are functional only for the rich, need to use urban space efficiently. There is some simple and well-proven maths about how to do this, which is also the maths of how transit systems achieve high ridership.

These cities need to organize themselves around frequent transit corridors, where big-vehicle frequent transit, bus or rail, can prosper, allowing the city to grow dense without growing vehicle trips.

Someday some of these corridors will be rail or Bus Rapid Transit. But the only way to grow enough corridors quickly, so that you cover much of the city with frequent service that can succeed in ridership terms, is to take frequent fixed-route bus service seriously. If you don’t do that in your land use planning, you’re going to end up building a city where fixed transit is geometrically impossible, and then you’ll have to settle for Musk’s vision. Geometrically, that vision can only mean liberating transportation just for the top 20 per cent – or electrified, automated gridlock for everyone.

Smart cities aren’t just the ones that chase the latest technology fads. They’re the ones that think carefully about the spatial, geometric problem that a dense city is. Because if it doesn’t work geometrically, it doesn’t work.

Jarrett Walker is an international consultant in public transit network design and policy, based in Portland, Oregon. He is also the author of “Human Transit: How clearer thinking about public transit can enrich our communities and our lives".

This article was originally written for his blog, and is reposted here with permission.

 
 
 
 

Here’s why we’re using a car wash to drill into the world’s highest glacier on Everest

Everest. Image: Getty.

For nearly 100 years, Mount Everest has been a source of fascination for explorers and researchers alike. While the former have been determined to conquer “goddess mother of the world” – as it is known in Tibet – the latter have worked to uncover the secrets that lie beneath its surface.

Our research team is no different. We are the first group trying to develop understanding of the glaciers on the flanks of Everest by drilling deep into their interior.

We are particularly interested in Khumbu Glacier, the highest glacier in the world and one of the largest in the region. Its source is the Western Cwm of Mount Everest, and the glacier flows down the mountain’s southern flanks, from an elevation of around 7,000 metres down to 4,900 metres above sea level at its terminus (the “end”).

Though we know a lot about its surface, at present we know just about nothing about the inside of Khumbu. Nothing is known about the temperature of the ice deeper than around 20 metres beneath the surface, for example, nor about how the ice moves (“deforms”) at depth.

Khumbu is covered with a debris layer (which varies in thickness by up to four metres) that affects how the surface melts, and produces a complex topography hosting large ponds and steep ice cliffs. Satellite observations have helped us to understand the surface of high-elevation debris-covered glaciers like Khumbu, but the difficult terrain makes it very hard to investigate anything below that surface. Yet this is where the processes of glacier movement originate.

Satellite image of Khumbu glacier in September 2013. Image: NASA.

Scientists have done plenty of ice drilling in the past, notably into the Antarctic and Greenland ice sheets. However this is a very different kind of investigation. The glaciers of the Himalayas and Andes are physically distinctive, and supply water to millions of people. It is important to learn from Greenland and Antarctica, – where we are finding out how melting ice sheets will contribute to rising sea levels, for example – but there we are answering different questions that relate to things such as rapid ice motion and the disintegration of floating ice shelves. With the glaciers we are still working on obtaining fairly basic information which has the capacity to make substantial improvements to model accuracy, and our understanding of how these glaciers are being, and will be, affected by climate change.

Under pressure

So how does one break into a glacier? To drill a hole into rock you break it up mechanically. But because ice has a far lower melting point, it is possible to melt boreholes through it. To do this, we use hot, pressurised water.

Conveniently, there is a pre-existing assembly to supply hot water under pressure – in car washes. We’ve been using these for over two decades now to drill into ice, but our latest collaboration with manufacturer Kärcher – which we are now testing at Khumbu – involves a few minor alterations to enable sufficient hot water to be pressurised for drilling higher (up to 6,000 metres above sea level is envisioned) and possibly deeper than before. Indeed, we are very pleased to reveal that our recent fieldwork at Khumbu has resulted in a borehole being drilled to a depth of about 190 metres below the surface.

Drilling into the glacier. Image: author provided.

Even without installing experiments, just drilling the borehole tells us something about the glacier. For example, if the water jet progresses smoothly to its base then we know the ice is uniform and largely debris-free. If drilling is interrupted, then we have hit an obstacle – likely rocks being transported within the ice. In 2017, we hit a layer like this some 12 times at one particular location and eventually had to give up drilling at that site. Yet this spatially-extensive blockage usefully revealed that the site was carrying a thick layer of debris deep within the ice.

Once the hole has been opened up, we take a video image – using an optical televiewer adapted from oil industry use by Robertson Geologging – of its interior to investigate the glacier’s internal structure. We then install various probes that provide data for several months to years. These include ice temperature, internal deformation, water presence measurements, and ice-bed contact pressure.


All of this information is crucial to determine and model how these kinds of glaciers move and melt. Recent studies have found that the melt rate and water contribution of high-elevation glaciers are currently increasing, because atmospheric warming is even stronger in mountain regions. However, a threshold will be reached where there is too little glacial mass remaining, and the glacial contribution to rivers will decrease rapidly – possibly within the next few decades for a large number of glaciers. This is particularly significant in the Himalayas because meltwater from glaciers such as Khumbu contributes to rivers such as the Brahmaputra and the Ganges, which provide water to billions of people in the foothills of the Himalaya.

Once we have all the temperature and tilt data, we will be able to tell how fast, and the processes by which, the glacier is moving. Then we can feed this information into state-of-the-art computer models of glacier behaviour to predict more accurately how these societally critical glaciers will respond as air temperatures continue to rise.

The ConversationThis is a big and difficult issue to address and it will take time. Even once drilled and imaged, our borehole experiments take several months to settle and run. However, we are confident that these data, when available, will change how the world sees its highest glacier.

Katie Miles, PhD Researcher, Aberystwyth University and Bryn Hubbard, Professor of Glaciology, Aberystwyth University.

This article was originally published on The Conversation. Read the original article.