1 / 41

Application of Cartogram in Sprawl Measurement

mareo
Download Presentation

Application of Cartogram in Sprawl Measurement

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    2. Outline of Talk A neglected problem in existing sprawl measures Use cartogram as a solution A case study in West Brookfield and North Brookfield, MA Conclusions Acknowledgement References

    3. Literature Review of Sprawl Measurement Methods Density-based measurements Population density based measures: the lower the density (especially in CBD), the greater the amount of sprawl. (Mieszkowski et al. 1993; Jordan et al. 1998; Nelson 1999; Kline 2000; Fulton et al. 2001; Nasser et al. 2001; Lopez et al. 2003; Lang 2003) Job density based measures: the lower centralization of jobs in CBD, the greater the amount of sprawl. (Galser et al. 2001(1); Galster et al. 2001 (2); Kahn 2001; ) Land use-based measurements Galster et al. (2000) used 8 indexes: Density, continuity, concentration, compactness, centrality, nuclearity, diversity, and proximity; Shen (2005), John Landis (2001) use three spatial indexes: continuity, compactness and fragmentation; Composite indexes Torrens and Alberti (2000) measured: density, scatter, leapfrogging, interspersion and accessibility; Ewing, et al. (2002) measured: residential density, neighborhood mix of homes, jobs, and services, accessibility, etc. Mieszkowski, Jordan measure density gradients; Nelson, Kline, and Fulton used developed land to calculate population density. Lang (2003) mentioned that sprawl cannot be adequately measured by density alone, each of these studies is nonetheless limited by its sole focus on density measures to the exclusion of other dimensions of sprawl. Galster et al. 2000, sprawl is more than just a factor of density. If it were, Los Angeles would be considered one of the United States’ most anti-sprawl metropolitan areas. Sprawl also contains the dimension of concentration.Mieszkowski, Jordan measure density gradients; Nelson, Kline, and Fulton used developed land to calculate population density. Lang (2003) mentioned that sprawl cannot be adequately measured by density alone, each of these studies is nonetheless limited by its sole focus on density measures to the exclusion of other dimensions of sprawl. Galster et al. 2000, sprawl is more than just a factor of density. If it were, Los Angeles would be considered one of the United States’ most anti-sprawl metropolitan areas. Sprawl also contains the dimension of concentration.

    4. A problem in existing sprawl measures Measure sprawl without excluding local natural factors (rivers, lakes, mountain, etc.). The results are: not-comparable across regions; with little policy implications. Problem has been partly noticed “Bodies of water, floodplains and wetlands”… “may interrupt the development pattern of an area. As a result sprawl may artificially appear to be intensified on various dimensions.” (Wolman et al. 2005) “Some discontinuities in land use could be generated by undevelopable land that might erroneously appear in sprawl measurements as leapfrog development.” (Cutsinger et al. 2005) Solution is still in need Use developed land in measurement cannot exclude the topological biases and development cost biases from natural factors.

    17. An example of Cartogram

    18. Use Cartogram as A Possible Solution A sprawl measurement should measure human development efficiency; be independent of local natural effects on developments. What is cartogram? A cartogram is a map in which shape area is proportional to one of its properties. (Gastner et al. 2004) – An example Apply “Cartogram” to equalize the development cost differences caused by local natural factors (including slope and land surface); exclude natural effects on development patterns, and sprawl measurements reflect only human development effects.

    19. A Case Study in West Brookfield and North Brookfield in Massachusetts Using Proposed Method

    20. Study Area and Data Study Area extended urbanized area (UA) in West Brookfield town, and North Brookfield town in Massachusetts; Spatial Unit 100m*100m grid Data Sources Land use/cover data – MassGIS Land Use Polygon UA boundary – ESRI Company Slope data – MassGIS 1:250,000 Hypsography contours at a 30-foot interval Geology data –USGS Geology Survey 1:7,500,000-scale map of Surficial Geology

    23. Method - Generate Cartogram Rubber Sheet Distortion Method (Dougenik et al., 1985) was used to generate cartogram. Total forces exerted from all polygons will cause each polygon to expand or shrink in responding to its value (here it is development cost): F ij = ( P j - q j) pj / d ij (1) Where: F ij = force exerted by polygon j on vertex i P j = square root (actual area)/square root (p ) q j = square root (desired area)/square root (p ) d ij = distance from centroid of j to vertex Code was redeveloped over original work by Erik Wolf (2006). Two improvements were made: allow un-developable lands to shrink; ensure convergence.

    24. Method – Sprawl Measurement Proximity The degree to which residential land use is close to other land uses (including residential, commercial, industry and transportation) when the size of developed area is controlled. Clustering The degree to which developments in the same type (including residential, commercial and industry) are close to each other when the size of developed area is controlled. Centrality The degree to which developed lands are located close to the CBD in study are when the size of developed area is controlled. Continuity The degree to which developable land has been developed in an unbroken fashion.

    25. Method – Development Cost Index Development cost index was defined as the inverse of unit development cost for parcels. Unit development cost for parcels were decided as follows: Flat area (slope<=8%) --- cost 1; Rolling area (8%<slope<=15%) with normal earthwork --- cost 3; with rock earthwork --- cost 5; Hilly area (15%<slope<25%) With normal earthwork --- cost 7; With rock earthwork --- cost 9; Undevelopable land --- cost 100, Slope >25%, or Water area, or Wet lands. Unit development cost was decided by using “American Association of State Highway and Transportation Officials’ (AASHTO) earthwork estimation data” as reference.

    30. Cartogram Map

    33. Map of Developed Land

    34. Comparison of Results Based on Land Use Map and Cartogram Map

    36. Method’s Sensitivity to Geography Note: * significant at 1% level.

    37. Method’s Sensitivity to the Start Point of Iteration

    38. Method’s Sensitivity to Boundary

    39. Conclusions Inclusion of natural factors cause negative or positive bias in sprawl measurements, and lead to biased policy implications; Cartogram can be applied to control sprawl measurements’ bias caused by natural factors. It produced obvious effects in our case study.

    40. Thank you for your time, and questions are welcomed!

    41. References Cutsinger, Jackie, George Galster, HowardWolman, Royce Hanson, and Douglas Towns,2005, \Verifying the Multi-Dimensional Nature of Metropolitan Land Use: Advancing the Understanding and Measurement of Sprawl." Journal of Urban Aairs 27(3):235-259. Dougenik, J.A., Chrisman, N.R. and Niemeyer, D.R. (1985). An algorithm to construct continuous area cartograms. Professional Geographer, 37(1). Ewing, Reid, Rolf Pendall, and Don Chen. 2002. Measuring Sprawl and its Impact. Washington, dc:Smart Growth America. Fulton, W., R. Pendall, M. Nguyen, and A. Harrison. 2001. Who sprawls most? How growth patterns differ across the U.S. Washington, DC: Brookings Institution. Galster, G., Hanson, R., Ratcliffe, M., Wolman, H., Coleman, S., & Freihage, J. ,2001, Wresting sprawl to the Ground: Defining and emasuring an elusive concept, Housing Policy Debate, 12 (4), 681-718. Glaser, Ed, Mathew Kahn, and Chenghuan Chu. May 2001. “Job Sprawl: Employment Location in U.S. Metropolitan Areas,” Brookings Institute Survey Series. Jordan, et. al., 1998. “U.S. suburbanization in the 1980s,” Regional Science and Urban Economics, 28: pp. 611-627 Landis, John D. 2001. Unpublished project report on urban sprawl in California.Department of City and Regional Planning, University of California, Berkeley.

    42. References (continued) Mieszkowski, Peter and E.S. Mills, 1993. "The Causes of Metropolitan Suburbanization," Journal of Economic Perspectives, American Economic Association, vol. 7(3), pages 135-47, Summer. Nasser, Haya El, and Paul Overberg. 2001. What you don’t know about sprawl. USA Today, 22 February, 1A, 6A–9A. Nelson, Arthur C.  1999.  Comparing states with and without growth management—Analysis baseed on indicators with policy implications.  Land Use Policy 16(2): 121-127. Kline, J. 2000. Comparing states with and without growth management: Analysis based on indicators with policy implications comment. Land Use Policy 17:349-55 Lopez, R., and Hynes, H. P., 2003, Sprawl in the 1990s: Measurement, distribution, and trends, Urban Affairs Review, vol. 38, p. 325-355. Lang R E, 2003 Edgeless Cities,Brookings Institution Press, Washington, DC Kahn, Matthew E., 2001, “Does Sprawl Reduce the Black/White Housing Consumption Gap?”, Housing Policy Debate, 12 (1): 77-86. Shen, Q., J. Liao, and F. Zhang. 2004. Changing Urban Growth Patterns in a Pro-Smart Growth State: The Case of Maryland, 1973-2000. Project Report, Lincoln Institute of Land Policy. Torrens P. M., and Alberti M., 2000. “Measuring sprawl”, Working paper no. 27, Centre for Advanced Spatial Analysis, University College London. Available online: http://www.casa.ac.uk/working_papers

More Related