Streetsblog New York City

Interesting choice of photos for Atlanta. The obvious view is of the massive 16 lane I-75/85 connector. However, that yellow bridge you see is a new connection to the redeveloped brownfield, mixed-use project called Atlantic Station. The bridge carries a new bus line and has new bike lanes. The project certainly has its faults, but it is a step in the right direction and one of many signs that American cities have turned a corner in terms of creating livable urban areas.

Just five years ago, the idea of putting bike lanes in Atlanta would have been a nonstarter. Now most cities across the country are rushing to make their cities more ped and bike-friendly. We still have a long way to go, and the process seems to be trickling outward from the city governments to the suburbs and upwards from local governments to the state and federal level. The point is, that it is happening. Case in point, Ray Lahood is talking about livable communities. When has a transportation secretary EVER talked that way?

We screwed up a bunch, and it will take decades, if not centuries to fix what we've done, both physically and psychologically. Despite all the progress we've made and continue to make, the US will be known as a car dependent place for at least 50 years; the same way the South Bronx has been synonymous with urban blight for the last 40 years, despite incredible progress. I guess the point is that we must continue to push ahead, in spite our reputation, and hopefully others will learn from our mistakes before it is too late.

> the US will be known as a car dependent place for at least 50 years

Some oil experts say we don't have 50 years. But I agree it is the height for hypocrisy for America to complain about rising auto usage in India and China. The appeal of the thing is apparently beyond rational consideration of issues like space requirements and mobility for all, which probably stems from its individual nature. Every driver thinks they're going to be the only one on the road.

Curious as to why you expect bike lanes on the I-75/85 downtown connector in the Atlanta photo. I'm pretty sure bikes and pedestrians are not allowed by law on interstates. But that big yellow bridge in the photo has both a bike lane and a bus lane. Just saying....

As a fan of streetsblog, am absolutely delighted that this op-ed was picked up and featured. Thanks a lot. Thanks also for insightful comments.

I agree with JSD about the comparison between Texas and NY/SFO being disbalanced. I made the comparsion based upon the availability of good data. I daresay that the story would be just as well told if I compared the New Yorker with a Houstonian and said, for instance, "four to five times" instead of "six to seven times". I just could not find the back up numbers. Would appreciate any pointers in that department.

On a more philosophical note, I believe that the crucial transit v sprawl battles are being won or (mostly) lost not on rural Wyomng roads, but in large metropolitan areas that, effectively, don't have transit. If one could wave a magic wand and somehow change transportation behaviour in, say, the largest dozen such communities (the San Antonios and the Vegases) - this would represent one of the, if not the, most significant stabs at solving global warming.
We are not going to windmill our way out of this one. We have to address and reduce demand and tackling sprawl, esp in America, is one of the most effective ways of doing this.

Thanks again. I look forward to and welcome any reax that you may have.

There will be cars beyond the oil age - last week's Times discussed China positioning as an electric car leader. Toyota and others will be bringing all-electric city cars to market by mid-next decade and plug-in hybrids before that. There's a big electrical load issue with this but there is a lot of work in efficiency, transmission and generation underway.

Projjal Dutta,

Annual Standardized Household CO2 Emissions, in lbs

Average for households in New York:

From Driving: 18,081
From Public Transportation: 6,386
Transportation total: 24,467

Average for households in Houston:

From Driving: 27,333
From Public Transportation: 1,447
Transportation total: 28,780

Source: http://economix.blogs.nytimes.com/2009/03/10/the-lorax-was-wrong-skyscrapers-are-green/

Thus, the average household in Houston produces only about 18% more carbon emissions from transportation than the average household in New York. I have no idea where you get your figure of "four to five times" from.

I think garyg also overlooks additional transportation-related indirect carbon emission costs: NYC being densly populated also has smaller houses and, in particular, row houses and apartment houses which tend to reduce heating and cooling costs considerably (see, e.g., the New Yorker article which was recently floating around in this blog). Of course, the transportation-related oil-industry in Houston doesn't help either ...

That the comparison is made against Texas rather Houston is not a trick; it's the whole point.

Then what is that point? What is the point of comparing the per capita emissions of an entire state, a state with an unusually hot and humid climate, with the per capita emissions of a coastal city with a temperate climate? What useful conclusions about land-use and transportation policy are we supposed to draw from that comparison?

If the purpose of the exercise is to try and illustrate the benefits of higher density and more public transportation, then a far more meaningful comparison would be to compare the average emissions for people living in suburbs vs. people living in central cities. And Glaeser does that in his paper. His findings indicate that average household emissions for suburban households are only around 10% higher than average household emissions for central city households. In other words, even if we could somehow radically transform the entire nation so that everyone lived at densities typical of people who currently live in central cities, we'd only reduce our total household carbon emissions by something like 10%.

Densification simply doesn't offer any potential for meaningful reductions in carbon emissions.

"See Table 2 on Page 41 ..."

Yikes, okay.

"I remain mystified as to where Dutta is getting that figure from (for either NY or SF)."

I don't know either. If there are no footnotes and Dutta does not speak up, the figure must be discounted. I think the difference would be greater between SFO and Texas than it would be between SFO and Houston (don't you?) but I'm not in favor of making up numbers either.

"Differences in emissions from air conditioning are mostly a matter of climate, not density."

Sure, that is what I was saying too.

"A difference in annual carbon costs of $500-800 is unlikely to persuade many people to live in San Francisco rather than Houston."

Well, who knows. If we agree that $500-800 is not so scary then we don't have to guess; we can implement a carbon tax and see how the market responds. People staying where they are and living more efficiently is also a win.

"a far more meaningful comparison would be to compare the average emissions for people living in suburbs vs. people living in central cities"

I agree, the Texas comparison is a little cheap. But it is more to the point than comparing SFO to Houston, as everyone seems to want to do.

"Densification simply doesn't offer any potential for meaningful reductions in carbon emissions."

10% down counts as meaningful in a country where emissions have gone only up. But also, in comparing the averages between central city households and their suburbs (not the entire nation), the differences are not huge in efficiency—or in lifestyle. The areas join each other. Some people on either side of whatever boundary has been drawn are leading functionally identical lives. It doesn't make sense to raise the spectre of cramming remote suburban families into a city apartment when the numbers are made up of families that are mostly in the middle.

If you want to specifically compare poles you can do that, a city family in an apartment building that occasionally rents cars compared an exurban family with at least one car or truck per parent and teen. But I don't think that's very helpful, whether the city family is described as having a low quality life or the exurban family is described as leading a wasteful life. The general story is what matters, and I hope we can get to 10% energy savings through land use changes that are not at all wrenching: suburbs that connect with each other instead of ending in planned dead ends, bicycle infrastructure in all communities, and yes, some densification. That can just as easily mean repopulating small towns as it does central cities. It will certainly mean rejuvenating old suburbs and leaving rural lands (the exurbs) to people that want to work them, and animals.

Projjal Dutta,

Total state energy consumption per capita is not a meaningful indicator of differences in energy consumption attributable to differences in residential land-use or personal transportation. Total state energy consumption includes all industrial and commercial energy consumption as well as residential and personal transportation consumption. Texas has a high total energy consumption per capita because it has so much energy-intensive industry, most obviously oil and natural gas production. As you can see from the EIA's industrial sector energy consumption estimates (http://www.eia.doe.gov/emeu/states/sep_sum/html/pdf/sum_btu_ind.pdf), Texas has by far the largest industrial sector energy consumption of all 50 states. Its industrial energy consumption estimate for 2006 is almost 6,000 trillion BTUs. New York's is only 461 trillion BTUs.

This has nothing to do with transit vs. automobiles or residential density.

Projjal,

You're still using statistics that are not meaningful indicators of energy consumption attributable to residential land use or personal transportation. The EIA data on energy consumption for the transportation sector includes both passenger AND FREIGHT transportation. Texas's huge oil, gas, petrochemical and mineral industries use vast amounts of energy to transport their products and raw materials. Aggregate transportation sector energy consumption doesn't tell you anything meaningful about differences in energy consumption attributable to the use of mass transit rather than automobiles for passenger transportation, or differences attributable to housing. In order to make that comparison, you need to isolate energy consumption for those purposes only, as Glaeser & Kahn did in the research I cited above. And they found that on average households in Houston produce only about 18% more carbon emissions from passenger transportation (driving plus public transportation) than households in New York.

Projjal,

No, I will not withdraw my statement that your data are not meaningful for your purposes. You're trying to use aggregate energy consumption data, including all energy used for industrial and commercial activity, to support a claim about the energy efficiency of public transportation and residential density. Your data simply do not support your conclusions. This isn't just a minor quibble. It's a fundamental flaw in your analysis. You have provided absolutely nothing to support your claim that "transit-rich areas are MANY TIMES more carbon-efficient than auto-dependent ones." And G&K's work explicitly contradicts that claim.

G&K compare household carbon emissions both between different MSAs (New York vs. Houston, for example), and between suburban and central city households within the same MSA. Not only are the differences between different MSAs quite modest, but the differences between suburban and central city households within an MSA are also modest. Something like 10%, on average. This implies that even if you could wave a magic wand and remake the entire country at densities typical of central cities, you'd only reduce carbon emissions by around 10%.