Overview | Urban Sprawl | Fringe Area Development | Urban Agglomeration | Emerging Technologies | Relevant Links
SIGMA0: Better Monitoring of Urban Change Dr. François Cavayas Geography Department, University of Montreal Montreal, Quebec, Canada Tel : +1-514 343 8016 Email: Francois.cavayas@umontreal.ca Dr. Yves Baudouin Geography Department, University of Quebec in Montreal Montreal, Quebec, Canada Tel: +1-514 987-3000 7706#, Fax: +1-514 987-6784 Email: Baudouin.yves@uqam.ca Claire Gosselin Synetix Inc., 5172 Chabot Street Montreal, Quebec, Canada Tel: +1-514-598-1991, Fax: +1-514-598-5775 Email: claire@gosselin.com  Dr. Réjean Simard Lasermap Asia Sdn. Bhd. Suite 2M, 2nd Floor, 2330 Century Square, Jalan Usahawan 63000 Cyberjaya, Selangor D.E., Malaysia Tel : +603 8318 0052, Fax: +603 8318 0049 Email: rejean@lasermap.com
Introduction Many public-sector agencies require current, reliable data on urbanized areas. Updating geospatial databases at scales ranging from 1:10 000 to 1:250 000 stands out as one of the major concerns of agencies involved in land management. What they are looking for is an uncomplicated, economical system for detecting urban change and map updating. SIGMA0, a new geomatics system aimed at updating land-use maps in urban areas with RADARSAT-1 imagery, could be just what they need. Current needs in urban areas Having a good appreciation of the development that takes place in urban areas on a near-continual basis is a concern that is common to a wide variety of stakeholders. A few examples of the existing interests related to urban development are outlined below. In many countries, few national government agencies if any at all, have a land-use management map for urbanized areas that cover large cities. When they do, the maps are in many cases outdated and thus do not show what has happened over the last five or even ten years. Large cities, such as Bangkok or Kuala Lumpur, on the other hand, need to update their land use/land cover maps as often as possible so they can more closely monitor the rapid development that takes place within their jurisdiction and make better urban planning decisions. Agencies that need to limit the rather costly acquisition of aerial photos used to closely monitor changes that have occurred in urban areas and particularly at the urban/agricultural fringe could make good use of a tool for detecting change which would enable them to better target their purchasing needs, thereby saving time and money. Last but not least, mapping agencies could benefit greatly from a tool that rapidly and systematically detects changes that have occurred in the built-up areas in urban, peri-urban, and rural settings. Radarsat: Useful data for map updating Many are advocating the integration of satellite imagery into the process for updating geospatial databases. Unfortunately, there is still no automated, rapid, and effective method for detecting change. The RADARSAT satellite offers a solution with images that have a resolution of 10 m and that are not affected by weather conditions. Aside from its characteristic speckle, radar images have a relatively simple structure and are sensitive to the presence of very high objects such as buildings. The appearance of new buildings on vacant lots is an undeniable change. Sigma0: Practical and economical system for map updating SIGMA0 is a geomatics system designed for updating urban land-use maps that is built on RADARSAT-1 imagery in fine resolution mode, which means a resolution of 10 m. It was developed by scientists from two leading universities in Canada and is being commercialized by Synetix Inc., a Canadian geomatics company, through financial assistance from the Canadian Space Agency and the Government of Quebec.
Page 1 of 2
| Next | |