Ecological Footprints Material (Resource) Flow Analysis

1. Ecological FootprintsMaterial (Resource) Flow Analysis Scott Matthews 12-712 / 19-622 Lecture 7

2. Administrative Issues • HW 2 Solutions, Returned • HW 3 Due Today • Thoughts on Due Dates for Final/etc? • Project Report Updates Due • Short class today

3. Timeline Planning Main question is when to make projects, take home finals due Note Friday 10/17 is “midsemester break”

4. Cities • More than 50% of population in cities, growing • Why the crunch from rural to urban? • Ability to meet needs locally versus needing to depend on transport/etc for fulfillment • Where does food come from (1000s of miles) • Not just a developed world issue – developing world shifting quickly • Interdependence, also globalization of production./cost minimization/etc • New supply chains, including refrigeration • Tradeoffs between simplicity of meeting needs locally versus potential scale of distant production. Which weighs more? • Urbanization tends to magnify the imapcts because of the large scale (non-linear)

5. Summary: An Ecological Footprint Process Factors in a number of categories of consumption and use Converts these inputs to a quantity of land One specific model used Redefining Progress Based on research of Wackernagel and Rees http://www.absentofi.org

6. Ecological Footprintfrom www.footprintnetwork.org (specifically the data/methods page) • An indicator that takes a variety of inputs and converts into equivalent land use • e.g., carbon emissions need biocapacity to be mitigated • Food/etc – land needed to farm it • Relevant benchmark “number of earths” (similar to carrying capacity) • “Earths” basis defined by biocapacity • See the reports and spreadsheets there if you have not already done so!

7. Biocapacity vs. Ecological Footprint • Units: global hectares (equivalent land measure) 2003 difference: about 25%. Meaning?

8. Delving Deeper into EF Approach • Majority of resources we use can be approximated by biocapacity (biologically productive area) needed to sustain it • Those that cannot be estimated are excluded (examples/effect)? • Describe the kinds of data needed for the biocapacity and EF side of such a comparison • Carbon land: first considers ocean uptake, everything else forest sequestration • Used to compare national resource consumption with bioproductive land available • 200 resource categories

9. In last 40 years,

10. Relevant Country Measures • Macro-level (total global hectares) and ratios for each country, and per-capita

11. Highest/Lowest • Where is US? • Top Five “Worst” Top Five “Best”

12. Lower Levels • Ecological Footprints at local levels “spatial ft-prints” • Same data/etc. • Alternate visualization • e.g., urban funnels (Grimm 2001)

13. Traditional Ecological Footprintsfor Phoenix, AZ

14. Distribution of Agricultural Food Production Increasing Data: US Department of Agriculture 1998

15. Distribution of Renewable Water Availability (Precipitation - Evapotranspiration) Precipitation: Daly and Taylor 1994; ET (Actual): Ahn and Tateishi 1987

16. Distribution of Carbon Assimilation Increasing Data: Century model by VEMAP project

17. Spatially Explicit Ecological Footprintsfor Phoenix, AZ Water Food Note –circles are traditional method of calculating footprint, for each resource

18. Central Arizona Project Canal EFs Domestic + agricultural water use CAP canal watershed Domestic water use only

19. Water EF for 20 largest US cities

20. Water EF with agriculture interaction

21. Caveats/Discussion • EF is just one, albeit highly controversial approach. • However its in the right direction of sustainability metrics, especially with respect to scientific data/methods and showing results by country/etc.