There are a plethora of criteria based on which each city should be judge as a green city, but the most important, in my opinion, are the following:
- Sustainable land usage: has the land been divided adequately between urban creations and the natural environment? Is there a balance between the two?
- Waste disposal methods: Are they sustainable? Do they recycle resources, to produce more useful products?
- Pollution: Compare the level of pollution over a number of years, and deduce a trend. Based on the trend, judge if the county has taken measures to reduce pollution.
- Education: What percentage of the population is educated? Are the aware of what it means to use resources in a sustainable manner?
All these criteria should be measured over years, and deduce a trend for better judgement.