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S T E P H A N I E P I N C E T L I N S T I T U T E O F T H E
E N V I R O N M E N T A N D S U S T A I N A B I L I T Y
U C L A
Urban Metabolism – The Political Ecology of Energy and Ecosystems
The World has Changed. . . Challenges of a Human Engineered Urbanizing Earth
Population growth GDP expansion of more
than 20X Global materials use
increased 8-fold Up to 83% of the global
terrestrial biosphere is considered to be under direct human influence
Reliance on non-renewable energy sources and water too
Materials use per capita doubled from 4.6 to 10.3 t/cap/yr (1900 – 2005)
Mineral fractions growing at a rapid pace
Biomass use slowing But, Human
Appropriation of Net Primary Production is between 30 – 58% globally
There has never been anything like the 20th century
Main driver of human induced environmental change is the growing social or industrial metabolism (an industrial sociometabolic regime)
Yet we are still lacking biophysical indicators such as primary energy supply, emissions, the use of specific substances Comprehensive account of global materials extraction
Materials flows
The Built Environment
Our built environment is a large in-use repository or stock humans have accumulated
Humans use approximately 60 billion tons of material every year, or the equivalent of the natural production of all plants on earth
Urban metabolism studies are the quantification of the flows into cities or communities (electrons, water, wood, air, other materials, food. . .) flows out as pollution, other waste or losses in the form of heat and distribution losses (absorbed by ecosystems), plus what has remained inside.
The Centrality of Energy
Energy is at the heart of human systems Availability of and cheap access to fossil fuels of high-
energy density and new and efficient technologies to convert primary energy into useful work allows for emergence of mass production and consumption and high level of energy and material use
Large infrastructures (buildings, roads, power grids, petrochemical complexes)
And a concomitant complex and path dependent economy, built environment, agriculture and consumption system
Place and Energy Systems
Urban areas concentrate the use of energy and materials Need to identify and to quantify current energy flows and
sinks in communities
By sector By region and microclimate By socio-economic and demographic characteristics By land use type By policy drivers
Traditional Expanded
Energy Materials Water Nutrients Waste
Demography, socioeconomic, education
GDP and community fiscal measures
Employment Health Community quality
Measures of Urban Metabolism
Land Use Transportation
Land use regs Densities Age of housing Finance and lending Taxation Impacts on hinterlands
Endangered species Soils, water, fauna and
flora
Materials and goods movement
Roads and transit Fuels Agriculture
Including
What UM can reveal
Appropriation of ecosystems and their functions Surface and groundwater Timber and minerals Fossil fuels Ocean resources And the sink capacities of ecosystems
Air pollution Water pollution Soil contamination
In quantities, location of resources
Ecosystem Services
In an expanded sense, an urban metabolism is fundamentally an artifact of the ways in which we enroll nature in our productive processes
Hence urban metabolism analysis draws attention to this reliance by identifying, quantifying and explaining the energy flows (including the resources) and the waste sinks
Fundamentally emerges from ecological concerns about systems and the second law of thermodynamics
Energy and resources foundational – and invisible to contemporary systems
Systemic nature of energy system: it is imbricated into each aspect of contemporary communities – a system that is interactive, interdependent and mutually constitutive with social systems
Deep path dependencies Many social, institutional rules, conventions, habits and
policies underlie energy and resource use These need to be revealed, examined and explained to be
able to change the drivers of existing energy and resource use
Question then turns to why and how
Institutions set the rules of the game in a society: they structure Human interactions – political, social, cultural and economic They structure our resource dependencies and implicitly
weight them – e.g. toward fossil fuels since they were cheap and abundant
Part of Urban Metabolism must be to identify these rules of the game
Some Examples
Federal water policy Colorado River Compact Central Valley Project Improvement Act
Minerals policies and pricing on federal lands Gasoline taxes Mortgage lending and banking policies Depreciation allowances Endangered Species Act Corporate laws
A systemic approach needs new methods and partners
Poor accounting of energy inputs and waste in our urban systems today, therefore planning for the future is planning in the void
Just as climate change science itself was a challenging interdisciplinary synthesis, urban metabolism – a systems approach -- demonstrates much of the same characteristics of different metrics, different epistemologies and concerns
Making a difference will require dedication to integration and examining the system – the whole is greater than the sum of its parts
A Return to Systems Thinking and Analysis
Systems thinking had a run in the 1970s But 1980’s to the rise of sustainability thinking
devalued integrated approaches Too complex Not needed Resurgence of ideas of economic man (the whole is just the
aggregation of individual decisions
Global processes like climate change have focused again on necessity for cross-disciplinary, integrated analyses to find solutions – back to systems