Critic’s Notebook - In Arabian Desert, a Sustainable City Rises

Duncan Chard for The New York Times
The terra-cotta-like exterior of a residential building in Masdar, a visionary city being built 20 miles from Abu Dhabi. More Photos »
By NICOLAI OUROUSSOFF
ABU DHABI, United Arab Emirates — Back in 2007, when the government here announced its plan for “the world’s first zero-carbon city” on the outskirts of Abu