Tuesday, October 27, 2009

Sprawl should be studied at various spatial resolutions

Yesterday was the first meeting of our workshop on peri-urban dynamics at the Technion – Israel Institute of Technology. It was intellectually stimulating to spend several hours with colleagues from Haifa, Tel Aviv and Ben-Gurion universities and our past and present grad students. There were geographers, experts in geo-spatial modeling, ecologists, urban planners and of course an urban economist.

We discussed the edge dynamics of cities and considered what is known about sprawl. The consensus around the room was that most of the literature relied on low resolution spatial data to identify and characterize sprawl. At best, the results are uninformative. The required characterization of sprawl should be in terms of the dynamics of natural systems within and at the edge of cities. In other words, when we think of sprawl we should model the urban system from the perspective of the dynamics of natural systems. Various resolutions should be considered. For avian population dynamics 3D porosity of cities is of interest.

At the workshop I presented some of our recent survey: Czamanski, D., Benenson, I., Malkinson, d., Marinov, M., Roth, R., Wittenberg, L., "Urban Dynamics and Ecosystems" in International Review of Environmental and Resource Economics, 2, 2008, pp. 1-45.

I cannot wait unitl our next meeting in Tel Aviv in two weeks.

Monday, October 26, 2009

The Great Cities in History

The Wall Street Journal published a brief review of John Julius Norwich's edited book that tries to identify cities that " played illustrious roles in the world's story". The title of the book is The Great Cities in History.

[http://online.wsj.com/article/SB10001424052748704500604574483701746375742.html].

"There are 68 cities here included (if we count ancient Constantinople and modern Istanbul as separate cities). Each is accorded a short chapter, written by contributors whose number includes Simon Schama (on Amsterdam and Washington), A.N. Wilson (on London) and Jan Morris (on New York). The cities under discussion range from the primordial Uruk to modern monsters like Sao Paulo, taking in, along the way, a host of conurbations from the ancient, the medieval and the early modern periods".

I always wondered what makes a city great. I will look forward to reading this book on my next trip.

Saturday, October 24, 2009

urban porosity


Urban sprawl has been around for ever. Reading recent contributions on measuring this phenomenon [e.g. Elena G. Irwin, Nancy E. Bockstael and Hyun Jin Cho, "Measuring and modeling urban sprawl: Data, scale and spatial dependencies" or Charles Jaret, Ravi Ghadge, Lesley Williams Reid and Robert M. Adelman, "The Measurement of Suburban Sprawl: An Evaluation".] I became interested in urban porosity. While sprawl is primarily a phenomenon of the urban edge, to describe it and to explain it, there is a need to understand the dynamics of cities as 3D physical objects.

As a preliminary step, there is a need for rules that will enable us to observe cities and to describe the extent and nature of porosity. I have been reading S.T. Hyde, S. Andersson, K. Larsson, Z. Blum, T. Landh, S. Lidin and B.W. Ninham, The Language of Shape, Elsevier, (1997) and Michael Burt's PERIODIC SPONGE SURFACES AND UNIFORM SPONGE POLYHEDRA IN NATURE AND IN THE REALM OF THE THEORETICALLY IMAGINABLE. I must admit that it is unclear to me where to go next. Any ideas?

At the same time, we are making a bit of progress in formulating the structural relationships that should be at the heart of the relevant modeling effort. See Czamanski, D., Roth, R., “Characteristic time, developers’ behavior and leapfrogging dynamics of high-rise buildings" forthcoming in Annals of Regional Science, 2009.

Wednesday, October 21, 2009

A new method for measuring and studying cities

Hernan D. Rozenfeld, Diego Rybski, Jose S. Andrade Jr., Michael Batty, H. Eugene Stanley, and Hernan A. Makse are among the leading scholars of urban phenomena today. They just published an important paper entitled "Laws of Population Growth".

The importance of the paper is in the effort of the authors to go beyond stylized facts and to introduce some precision into the measurement of urban phenomena. What we know about cities is very much influenced by the way we mark the boundaries of cities and the way that we collect data about cities. For the most part cities are defined as administrative and governmental units. In reality, cities extend beyond such boundaries. Often a city spans several municipal units.

To overcome the obvious problems of traditional data collection, the authors "introduce a new method to designate metropolitan areas, denoted “City Clustering Algorithm” (CCA). The CCA is based on spatial distributions of the population at a fine geographic scale, defining a city beyond the scope of its administrative boundaries".

By applying this measurement method they find scale-invariant properties which they "modelled using long-range spatial correlations between the population of cells". This leads to the implication that "strong development in an area attracts more development in its neighborhood and much beyond. A key finding is that small places exhibit larger fluctuations than large places. The implications for locating activity in different places are that there is a greater probability of larger growth in small places, but also a greater probability of larger decline".

You can find this paper at: Http://arXiv.org/abs/0808.2202v2

Saturday, October 17, 2009

A Joint Workshop in Peri-Urban Spatial Dynamics


During the academic year 2009-2010 Prof. I. Benenson (Tel-Aviv University), Prof. D. Czamanski (Technion - Israel Institute of Technology), Dr. D. Malkinson (University of Haifa) and Dr. Nurit Alfasi (Ben-Gurion University) will lead a year-long workshop that will explore the spatio-temporal interactions among urban, ecological and agricultural systems in the peri-urban zone.

The workshop will meet every two weeks, alternating between the Tel Aviv University and the Technion campuses. The meetings will take place on Mondays between 16:00 and 19:00. The first meeting is scheduled for the 26th of October, 2009 at the Technion.

Participants in the workshop will include senior researchers, graduate students and post-docs.

We intend to use this blog to exchange ideas raised in the workshop.

You are invited to comment and participate in these discussions through this blog.

The 2010 Advanced Geographical Analysis and Modeling Workshop

The increasing availability of geographic information and new spatial models originating in physics, economics and regional science, pose a challenge and present an opportunity for Geographic Information Science.

The Modeling Geographical System and the Geographic Information Science Commisions of the International Geographic Union would like to invite you to participate in a workshop that will be an exciting opportunity to explore with other scholars issues related to geospatial analysis and modeling. The workshop precedes IGU 2010 Regional Conference.

The workshop will take place on July 8th-10th, in Neve Ilan, located approximately 20km west of Jerusalem.

We look forward to seeing you at the workshop and encourage you to submit papers for presentation at the meeting.

Further details at: http://www.agam2010.tau.ac.il/

Regional Science and Complexity Sessions at ERSA 2010 Congress

Following the complexity sessions in Liverpool in 2008 and in Lodz in 2009, the local organizing committee of 2010 ERSA Congress has given a green light to organize similar sessions in the coming meeting in Jönköping, Sweden (19-23 August 2010).

The Regional Science Association (RSA) is a natural venue to explore spatial phenomena by means of ideas from statistical mechanics concerning micro-behavior and macro-states. While such analyses have been around for some forty years now, dynamic simulation in Regional Science is relatively new. This is despite the obvious analogies of economies as self-organizing, emergent systems. Recently, research in the spirit of the New Economic Geography has illustrated the emergence of the urban patterns from some very basic economic principles. Heretofore a major obstacle to a fruitful dialogue among these disciplines has been the intention of regional scientists to reproduce reality and the aim of statistical physicists to capture the essence of phenomena, making the explanation "simple as possible, but not simpler". It is our presumption that there is a possible meeting point that can be identified and that lies at some mid-point between the real and the essential. Again at the 2010 European RSA we intend to explore the possibility of finding this meeting point among regional scientists and physicists. We think that the joint exploration of this topic by statistical mechanics and regional science can be interesting and fruitful.

By means of this letter I would like to invite you to participate in these sessions by contributing a paper. Come to explore with other scholars the growing dialogue among physicists, economists, geographers, planners and regional scientists concerning spatial phenomena. We are issuing this invitation almost a year before the meeting hoping that we can receive commitments early and so that we may be able to organize a book that will include the papers to be presented at the meeting. The deadline for the abstracts is 31 December 2009.

Please send your abstract as soon as possible to Danny Czamanski at danny@czamanski.com.