To gain a little context, a good starting point would be to compare London to other cities around the world. So who is already taking green action and how can we measure this? Carbon footprints, the number of cars in the city and water usage are a few ways to put numbers onto a sustainable city.
Carbon
London is in third place of most carbon intensive people, beaten by New York and Amsterdam. But London has ambitious targets of cutting CO2 by 60% by 2025 – that’s in 12 years time.
Transport
Who’s driving the most cars or taking public transport? Around two-thirds of London’s eight million people take public transport to work –rallied on with bike promotions such as Boris bikes and the sleek new hybrid red buses.
Water
Wasteful water? Due to old water systems, London loses around 23% of water through leaky pipes and inefficient carrying systems. But overall water usage is much lower than other cities.
Data and graphs from http://www.fastcoexist.com/multisite_files/coexist/imagecache/inline-expanded/inline/2012/10/1680739-inline-green-cities-final.jpg
The Green Rooftop 
