Photo credit: Graham I. via Flickr.

(This is a post from the TH City Series. Find the rest here) Ever since the 2001 economic crash, Buenos Aires has been blooming as one of the most exciting cities in the continent. Often talked about as South America’s “little Paris”, Argentina’s capital has the perfect mix of Latin and European flavors and a cultural offer that matches those of the most developed cities in the world. Did you know, for example, that it holds more than 140 private and public museums (Wikipedia)? Or that the number of theaters in the city is one of the highest in the world?

With a population of over three million and thirteen million counting the suburbs, this is also one of the biggest cities in South America.

And even though Argentina is held responsible for some major eco-disasters (like the contamination in Rio de la Plata and the Matanza Riachuelo), in the last years the city has also seen develop many green designers, some green design events, and even recycling initiatives from the government. That's why we'd love that all of you Buenos Aires treehuggers told us about this amazing place.

Sydney is white Australia's birthplace, settled as a penal colony in 1788. Many of its first white inhabitants would be very surprised to learn that it is now often recognized as one of the world's top ten most liveable cities. Earlier this year it was ranked as the world's most favourite city by the Anholt City Brands Index. And Grist dubbed it 10th in their list of the worlds top fifteen Green Cities. And there is much to be thankful for in this city of about 4.3 million souls, which is also considered one of the globe's most cultural diverse metropolis, with around 140 different ethnic groups. Sydney is the capital city for the state of New South Wales (NSW), but contrary to popular international misinterpretation, not of the nation. That is Canberra.

Geographically Sydney has the largest natural harbour in the world, is famed for its beaches (having over 70 of them), and is blessed with mostly sunny, mild weather, lending the city a very outdoorsy lifestyle. Particularly when surrounded on three sides by national parks, one of which is the world's second oldest (after Yellowstone), and another a World Heritage area. With the Pacific Ocean taking up prime position on the fourth side, Sydney has become a victim of its own success. It has reached the limits of its natural basin, and there is no room in the inn. Land for housing and infrastructure is at a premium.

photo credit: Wally Gobetz via Flickr

It is a beautifully sunny day here in London, I am happy to say that summer has finally arrived on these shores. It feels like a good day to cycle along one of the many tow paths down by the River Thames or to take stroll through one of the gorgeously green and leafy public parks that are dotted all over this sprawling metropolis, if you are not stuck in a stuffy office block that is. London is the most populous city in Europe with 7.7 million of us living here, so we know there are a lot of you out there who can tell other TH readers what life is like in this great city. We'd like to know, in TreeHugging terms, what are the best and what are the worst things about London? What is the general level of eco-consciousness among the population? How's public transportation? How is it for cyclists? Does anyone actually use Oybike? Has anyone caught a Hybrid taxi? What about the Suburban sprawl? Are you benefitting from the Congestion Charge system? Air quality? Has the recent smoking ban helped? Recycling/composting? As time passes, are things getting better or worse?

Awhile back, we initiated a series of posts encouraging our readers from across the globe to tell us about their cities: the green good, bad and ugly of the city, including things like public transportation, suburban sprawl, air quality and other considerations often given when looking at the general "greenness" of urban areas. We learned some interesting things.

1) In Portland, Oregon, we learned about the ease of biking around town, and the rain.
2) The people of Austin, Texas told us about the reliable public transportation but lamented that it's still in Texas.
3) In New York City, we heard all about the great public transit, hybrid cabs, efficient space use but were reminded of all the pollution: noise, light, and garbage.
4) The citizens in Toronto, Ontario were equally pleased and upset by the bicycle-friendliness of the town, but many agreed that public transit was getting too expensive.
5) Lester Brown pointed out that, almost without fail, big cities are unhealthy, inefficient places to live, though they don't have to be.

[This is a guest post by Steve Cohen, Executive Director of the Earth Institute and Director of the Master of Public Administration Program in Environmental Science and Policy at the School of International and Public Affairs at Columbia University. -Ed] New York City is America’s largest and most diverse city. Its 2006 expense budget of over $50 billion makes it far and away the largest local government in the United States. While the city appeared under enormous fiscal, political and social stress from the late 1960’s to the late 1990’s, in the 21st century it has emerged as one of the safest large cities in the United States. New York is a thriving center of media and finance, and a racially and ethnically diverse place where in the 2000 census 40% of its residents reported that they were born in other nations.

Urbanization is one of the dominant demographic trends of our time. In 1900, 150 million people lived in cities. By 2000, it was 2.9 billion people, a 19-fold increase. By 2007 more than half of us will live in cities—making us, for the first time, an urban species. (See Chapter 11 in Plan B 2.0).

In 1900 there were only a handful of cities with a million people. Today 408 cities have at least that many inhabitants. And there are 20 megacities with 10 million or more residents. Tokyo’s population of 35 million exceeds that of Canada. Mexico City’s population of 19 million is nearly equal to that of Australia. New York, São Paulo, Mumbai (formerly Bombay), Delhi, Calcutta, Buenos Aires, and Shanghai follow close behind.

Recent Comment by futurebird : "I respectfully dissent: An analysis of combined urban-suburban area is going to yiel..." [read]

The latest addition to our City Series is a big one: New York City. By now you know how it works: We want to know what are the good, and what are the bad things going on there. What is the general level of eco-consciousness in population? How is it for cyclists? How's public transportation? Suburban sprawl? Air quality? Recycling/composting? As time passes, are things getting better or worse? How are the policymakers? Anything you think we might find interesting, please share it with us in the comments of this post.

By now you know the drill (this is the third post in our City Series, see the first two: Tell Us About Portland, Tell Us About Austin): We want to hear from you, people of Toronto. What is the general level of eco-consciousness in population? How is it for cyclists (we know it can be dangerous)? How's public transportation? Suburban sprawl? Air quality? Recycling/composting? Urban planning? Green roofs? As time passes, are things getting better or worse? Anybody has experience with Windshare, the "urban-based wind power co-op"? Anything you think we might find interesting, please share it with us in the comments of this post. Please share your experience in the comments.