This recent article by Brookings is a good reminder of the all too important link between land use policies/patterns and GHG emissions. Because electric vehicles are cool and all, but they're still not as efficient as just walking around and/or taking transit.

As has been argued before on this blog, we need to not only electrify our transport network, but we also need to change how we get around. And probably the best way to encourage a modal shift, is to plan and build our cities differently. Something that is simple, but not easy.

It also turns out that people who live in multi-family buildings tend to consume less energy (on a per capita basis) than those in single-family houses. So there are numerous benefits to encouraging denser housing on top of transit and within mixed-used communities.

With all of this in mind, here are some interesting charts from the above Brookings article.

This first one shows new housing permits in the metro areas of Atlanta, Chicago, and Washington DC, according to their urban, suburban, or exurban status. Here, Chicago is an outlier, with the "urban core" (defined as Cook County) now making up about half of all new housing.

If you look at the entire study period, the number is less. The urban core accounted for about one-third of new housing permits in Chicago, and only 15% of permits in Atlanta and DC. But in all cases, housing permits in the urban core have been increasing since the 2008 financial crisis.

But here's the other thing. Looking at these next two charts, there appears to be a clear trendline toward more urban housing typologies. The first of these next two is showing single-family housing permits as a percentage of all new housing. And the second is structure type over time.

Atlanta is still building mostly single-family housing, but less of it. And based on these charts, Chicago has already passed its inflection point. DC is not far off. Every city region is of course going to be different, but it does look like there is some kind of broader housing shift underway.

New York City is projecting that Lower Manhattan is likely to see more frequent flooding by as early as the 2040s. This could move to monthly flooding by the 2050s and daily by the 2080s. These time horizons may seem like a ways away, but I'm personally going to try my damnedest to see the 2080s.

In light of these projections, New York City released a new Financial District and Seaport Climate Resilience Master Plan at the end of last year. The plan is projected to cost somewhere between $5 to $7 billion and entails building out a new multilevel waterfront that extends the current shoreline into the East River by up to 200 feet.

Here are a couple of renderings:

The upper level will be elevated by about 15-18 feet (designed to protect against storms like Sandy) and the lowest level will be a continuous waterfront esplanade (designed to connect humans to the water). Overall, the plan encompasses about one mile of waterfront, running from The Battery to the Brooklyn Bridge.

City building take times. In the case of this plan, it is building for the next century.

For a copy of the full press release, click here.

Images: NYC Economic Development Corporation

One of the main criticisms of cryptocurrencies is that they consume a lot of energy and are therefore not sustainable. But all blockchains are not created equal and there are different ways in which transactions on a blockchain can be validated.

Bitcoin and Ethereum use something known as "proof of work" (though Ethereum plans to change this sometime next year). This method of validation does indeed use quite a bit of energy.

But another way to validate and maintain security on a network is through something known as "proof of stake." This is what Solana and many other blockchains are now using. Put differently, there's no "mining" required, which is the work that is so energy intensive.

To demonstrate the difference, the Solana Foundation recently published this comparison chart:

To try and further put this into context, the entire Solana network is currently doing about 20 million transactions per year. Right now, they are claiming that this is equivalent to the electricity usage of about 986 American households.

If you'd like to take a look at the footnotes, click here.