MIT Uses Algorithms to Find the World’s Greenest Cities

Tim Nelson
Updated

While there’s a general consensus on their importance, there’s less agreement on how green cities should be quantified and measured. Though latest effort from MIT’s Senseable City Lab may not fully put that ongoing debate to rest, it certainly represents a leap forward in how this sort of urban planning data can be collected.

Spearheaded by Newsha Ghaeli, Treepedia is an interactive, map-based platform that measures tree canopy coverage in cities around the globe. As opposed to other satellite-based methods that rely on overhead views to assess the extent of greenery, Treepedia leverages an algorithm that can scan Google Street View images and determine what percentage of them are made up of trees. The end result of Senseable City Lab’s block-by-block scan is their Green View Index (GVI), which “represent[s] human perception of the environment from the street level.”

Of the cities to be analyzed so far, Singapore is far and away the greenest, earning a GVI score of 29.3%. It’s followed by Sydney and Vancouver (both at 25.9%). With a GVI of 25.3% MIT’s home base of Cambridge, Massachusetts is the highest-ranking US city currently on the list.

With canopy coverage a measure of environmental welfare that’s increasingly tied to public health outcomes, Treepedia hopes to offer a universal yardstick by which efforts to green up city streets (parks and other natural areas aren’t part of the evaluation) can be measured. And while a reliance on Google Street View images means China and India can’t be analyzed, the use of an algorithm to collect this sort of data certainly opens up exciting possibilities for the future.

See the full list of the ten greenest cities (so far) below, and play around with Treepedia yourself here.

  1. Singapore (GVI: 29.3%)

  2. Sydney and Vancouver (GVI: 25.9%)

  3. Cambridge (US) (GVI: 25.3%)

  4. Durban (GVI: 23.7%)

  5. Sacramento and Johannesburg (GVI: 23.6%)

  6. Frankfurt (GVI: 21.5%)

  7. Geneva (GVI: 21.4%)

  8. Amsterdam (GVI: 20.6%)

  9. Seattle (GVI: 20%)

  10. Toronto (GVI: 19.5%)

See the videos.