In the many slums I have visited in Latin America, Asia and Africa, I am always struck by the resourcefulness and resilience of residents. Slum dwellers face many hardships in their daily life – low incomes, overcrowded living conditions in high risk areas such as flood zones or steep hillsides, and limited access to clean water, sanitation, transport or solid waste services.

These challenges are only made worse by the impacts of climate change and natural hazards. Heavy rains can quickly turn into a disastrous flood as a result of insufficient or ineffective drainage.  Such flooding can destroy the limited assets of poor households, halt economic activity, contaminate water supply, lead to disease and displace residents.   With the increase in weather extremes, it is anticipated that such events will happen with recurring frequency.

Detroit: A Biography by Scott Martelle provides a unique glimpse into the life and history of one of America’s used-to-be, and maybe-again, great cities. From the outset you can tell that Mr. Martelle is more than an observant journalist; he’s a native. He’s got skin in the game.

Providing a biography of Detroit is a clever way to help the reader understand the nuances of what brought the city to where it is today. But the book reads more as an obituary than a city-in-progress biography. The closing Epilogue claims, “There is no real answer to the troubles afflicting places like Detroit”.

Moving from California to Washington DC, I did not expect to find revolution; but I have. Fellow city-dwellers are overthrowing old models of consumption (through which their cities became extractors and importers of natural resources and exporters of waste products) by simply changing their habits. One by one, urban citizens are choosing collaborative consumption instead, to save money, resources, and time.

Though sharing is not new – in fact, historically, people lived and consumed resources in groups – it is an innovation in the modern city. A diverse set of sharing mechanisms has sprouted – for-profit, non-profit, informal, and formal – many of which use the web to match supply and demand.

Instead of purchasing cars, consumers are using car-sharing companies (like Zipcar), which allow them to rent vehicles by the hour, or stopping by to get a ride from the Casual Carpool in San Francisco or the Slug Line in Washington DC, two informal, citizen-organized carpool sites that match car-free commuters with drivers looking to enter High Occupancy Vehicle (HOV) lanes and save on toll fares.

Growing up on a farm meant I spent very little time in cities. I felt more at home when surrounded by green than grey. As a kid, I saw cities as noisy, bright, busy and quite frankly, confusing. I always thought to myself why would anyone want to live in them? However, when I grew up, I moved to a city to take advantage of the opportunities it provided. I am not alone. More than 50 percent of the world’s population lives in cities and this number will rise. Cities are hubs of productivity, innovation and vast human capital; but once you live in them you begin to see that they are like any other ecosystem: complex and fragile, whose balance can be easily disturbed. With many cities rapidly growing and evolving, how do you manage this increasing complexity without destroying the ecosystem?

Geographical Information System (GIS) techniques have proven successful in mapping, analyzing and managing natural ecosystems. It is now time to make use of the same technology to manage, model and design our expanding global system of cities. GIS consists of a proven set of tools that can provide information to leaders at the local and national level to facilitate evidence-driven decision making. It allows us to move beyond 2D paper maps and incorporate everything that lies below, above and around a city to create a 3D digital representation of the city’s ecosystem. By integrating this information into the planning process, it will hopefully lead to harmonized planning across sectors. For example, integrated transport and land use planning and development will allow for economic, social and environmental benefits. More sectors can then be incorporated, with this integration not only happening within the city limits but including the urban periphery, where a lot of urban expansion is currently occurring. This holistic view will allow planners to make cities more livable.