But don't you see, you're just reinforcing the point about how impossible all of this is.  

First off, making a 25% cut in the amount of driving done by the population of a city the size of Atlanta will, by itself, do exactly nothing to stabilize atmospheric CO2 at less than 500ppm.  If by magic--I can't imagine how else you'd do it--you could enforce a 50% reduction in miles driven by EVERY CAR IN THE ENTIRE WORLD, even that drastic change would account for only 10-15% of the reduction in CO2 emissions to stabilize atmospheric [CO2].

Second off, you can't just turn Atlanta into Boston.  The infrastructure's already in place.  We're talking about what we can do to prevent a doubling in atmospheric CO2 by 2050.  That's 42 years from now.  And to make a dent, the changes must go into effect TODAY.  I mean, what do you propose?  Maybe if Barack Obama wins the general election he could appoint Al Gore Climate Change Czar and grant him the dictatorial powers of an actual czar.  Gore could then use the National Guard to relocate the residents of suburban Atlanta--and Charlotte, and Dallas, and Indianapolis, and Chicago, and Phoenix, and the entire states of California and New Jersey--into a series of ultradense high rise conglomerations modeled after Hong Kong.  

Seriously, it'd be great for the environemnt if everyone lived the way Manhattanites do.  But we don't, and no amount of wishful thinking and greenie think-tank position papers will make it so.

60-80% of greenhouse gases comes from  power plants. Cars are a total red herring. And we already have the answer for that if people would open their minds to some real science.

Suburban sprawl not only costs carbon in terms of auto miles driven. It also imposes the additional energy costs of stand-alone housing, the provision of urban utilities to remote areas. Some places, especially in the Sunbelt, are uninhabitable without ubiquitous air conditioning. Las Vegas, aargh! Not to mention the geo-political-economic costs of America's dependence on energy imports. Ever heard of Iraq? It makes me sick to think that young people are dying in Iraq so that decadent over-weight barbarians can race Hummers, USA flags sticking out the windows, boom box music blarring, on American roads. Never mind the health costs of the automobile society. So we not just trying to reduce carbon outputs here.

As for infrastructure being immutable, that ain't so. Infrastructure decisions, most bad ones, are being made everyday in the USA at all levels of government. It's usually in favor in more sprawl and more highways. Atlanta can't be made into Boston overnight with a "shazzam!". But Atlanta, with a different vision, can be transformed over a decade.

If nothing else convinces Americans to mend their ways, it will be rising energy prices. We will have to cut energy expenditures to survive the global economic competition. I love my fellow Americans, but they're a really smug bunch.

The entire solution to commuting is in our hands today, but no one seems to want to use it.  It's called telecommuting.  Videoconferencing can be done from anyone's computer that's got broadband access with no difficulty.  Corporations do dabble with this, but the big G won't even get close.  This is our biggest problem and it's really our own Government that's the biggest impediment.  There is no reason today that 3/4 of the 'services' population shouldn't be able to work from home.  

Why are there sales people at tire stores?  All they do could be done over the Internet.  Same for tons of others.  We've got to start looking at the demand side of this mess instead of trying to find another source of energy to keep our addiction going.

Brad, one of the wedges is "drive two billion cars not 10,000 but 5,000 miles a year."

We know that building compact, walkable communities reduces CO2 emissions, not only by giving people transportation choices (for all kinds of trips, not just work trips) but by making buildings more efficient and by limiting the loss of carbon-fixing green space at the urban edge. "Sustainable urbanism" address no fewer than seven of Socolow and Pacala's 15 policy wedges -- most directly numbers two and three, reducing VMT by 50% and electric use by 25%, and indirectly addressing others by embedding renewable generation into new buildings. All it requires is that we simply build good cities -- a "technology" which humans have already known about for thousands of years.

We will need to use every available strategy in order to achieve the dramatic carbon reduction targets that have been proposed. Driving less is the single biggest thing that American households can do today to cut their environmental footprint -- and it will probably make us a healthier, wealthier society besides. In fact, Americans in 2008 are already driving less, compared to 2007: we're discovering that spending $4 a gallon just to get stuck in traffic is not happy. (Places like Vancouver and Portland have seen population grow and VMT decline for several years.) Some of the fastest growing neighborhoods in America are dense, mixed-use areas near downtowns. Federal and state governments should encourage these trends with smart policies -- instead of stealing from the transit budget to build highways, as the Bush administration has proposed.

This post is idiotic.  First, take a look at a map.  Boston has water to the east.  This might have some influence on the amount of sprawl.  Second, in case you haven't heard, the real estate market is in the toilet.  Are you suggesting that gas prices are the cause of lower home prices in the outer suburbs?  

"'Sustainable urbanism' address no fewer than seven of Socolow and Pacala's 15 policy wedges -- most directly numbers two and three, reducing VMT by 50% and electric use by 25%, and indirectly addressing others by embedding renewable generation into new buildings. All it requires is that we simply build good cities -- a "technology" which humans have already known about for thousands of years."

Sure, but to have any hope of holding atmospheric CO2 at under 500ppm--double the preindustrial concentration--at 2050, somewhere between 7 and 10 of Socolow's and Pacala's wedges wouild have to be fully implemented within five years of their articles publication, a deadline now just one year away. For all that sustainable development is a good thing--and I don't deny that it is--to argue that gearing FUTURE development toward higher density, more energy efficient schemes can meaningfully impact the global warming problem reflects a fundamental misunderstanding of the magnitude of the atmospheric CO2 problem and of the magnitude and urgency of the changes required to mitigate it.

Socolow's and Pacala's position is that if, starting now, we can end the acceleration in the rate of CO2 emissions and stabilize them at 7 gigatons of carbon/year, we can keep [CO2] under 500ppm by 2050 at which time, they hope, major new techonological breakthroughs will have permitted us to curtail the use of fossil fuels altogether.   Think about what this means.  Right now, the world economy is grounded on energy generated from fossil fuels.  Do you intend to peg growth in productivity at zero?  How would that work?  Can it even me made to happen?  You'll answer that if some scheme can be derived to ensure that the price of fossil fuels realistically reflects their environmental cost, that this will encourage the world economy to grow in novel, non-carbon-based directions, into alternative and nuclear energy,  One thing that might happen under such a regime could be that the cost to commute from and air condition a McMansion out in Conyers, GA might rise so precipitously that its owners might be encouraged to abandon it for a highrise apartment in downtown Atlanta, or else to take in a number of boarders and thereby increase the population density and hence the energy effiency of their dwellingplace two or three-fold.  But these sorts of changes evolve over decades.  As Socolow and Pacala ably demonstrate, we don't HAVE decades.

I think it entirely possible that the 21st century will see a new wave of violent anarchism.  If such a movement were to get started, it would probably begin in Europe where violent radicalism is much more deeply ingrained than it is on North American shores.  But we need to recognize that the pace of change that writers like Socolow and Pacala advocate is truly revolutionary.  And when people start to believe that revolutionary change is what is needed to avert some sort of universal disaster--in this case climate change--a revolutionary movement advocating direct action may not be too far in the offing.

Here's a link to Socolow's and Pacala's paper:

carbonsequestration.us/.../Pacala-Socolow-ScienceMag-Aug2004.pdf

Telecommuting? Tell that to the security people where I work. We do not have any connection to the Internet. Nothing enters or leaves the work area. Inside there is an elaborate communications network, but it can not be contacted from outside. I have to go through three doors with cipher locks to get to my desk. Telecommuting can work for only a few people. Most must get to their work place to do anything useful. There is only a small percentage of jobs where telecommuting is a reasonable alternative.

Encouraging a compact urban area well served with public transit would certainly save on carbon emissions. A more extensive public transit network would likely level housing prices as well by making it easier to commute long distances. The bad news is that public transit running on electricity means mining and burning coal. The good news is that American has 50% of the world's known coal reserves. The world supply of uranium, the green equivalent of coal, is much lower in potential energy generation than the supply of coal.

If we want to reduce our carbon foot print, conservation is the most efficient way to go. Colder houses in winter and warmer houses in summer. How about tax credits for solar collectors on houses and businesses, more insulation in buildings, geologic heat pumps, etc., which is a one time subsidy. Biofuel subsidies are forever. There is no magic bullet, but conservation comes closer.

Certainly, the declining in housing prices further from the center of the city is partially due to commuting distances, but it's also due to demand.  Where I live, they have over built these new subdivisions to the point where there is really no one left to buy them.  Then, the builders of these new houses start, dropping their prices to encourage people to buy them (offer them zero down mortgages through shady mortgage brokers) which lowers the prices of the slightly older houses, the ones built two years ago by the same builder, three blocks closer to the center of the city.   Even worse, people interested in buying a home out in the burbs are not going to buy your two or three year old house when there is a brand new house just a few blocks down the street.  In the meantime, houses closer to the center of the city are less affected as there is not a huge supply of housing available older, more established neighborhoods.

Brad:

The problem is that when home prices fall in the suburban fringe in an area like DC (where you have non-existent unemployment), that actually encourages more folks to live out there. It's a Catch-22....if we can't address the affordable housing issue in these hot markets, we'll continue to encourage long commutes.

( Image courtesy the Libary of Congress .) Having found success throughout Europe, a sponsored bicycle

Brad, a member of my family is in the business.  Home prices in neighborhoods closer to the central city climb higher and at faster rates than those in outlying suburbs; that occurs irrespective of gas prices.  And, in times of over-supply, have declines at slower rates.  The same house on the same size lot will cost more in McLean than it will in Burke.  Home builders have a saying, "drive until you qualify."  I'm sure gas prices have an impact, but that fact does not explain the phenomenon you describe. [Sorry for the opening in my first post; I should not have written it.]