Wednesday, December 7, 2016

Percentage of urban areas in Montreal, Toronto and Vancouver CMAs

Question
I have been asked if I could provide the percentage of urban areas (in square km) for the Montreal, Vancouver and Toronto CMAs. My understanding is that this would translate, in terms of the 2011 Census geography, in the area covered by Population Centres within those CMAs.

I’m not sure if those numbers are readily available, but I thought I could calculate them using GeoSuite 2011 by:
  • Generating a list of POPCTR areas for each CMA, making sure to exclude any rural area (POPCTRRAclass = 1)
  • Adding up the values of the POPCTRRAarea field for all population centres
  • Dividing that result by the area of the CMA
Can someone confirm that is an accurate method for calculating the % of the area covered by urban/population centres within a CMA?

Answer
GEO has provided the following response:

“We talked with subject matter on this. The methodology presented by the client is reasonable. The two things to remember are:
  • PopCentres do not overlap CMA boundaries
  • There may be multiple PopCentres of different types (Primary, Secondary, Fringe) within a CMA
So, removing the Rural Area PopCentres and calculating land areas with the remaining seems to be a valid methodology.”