1. ERE2: Sustainability The origins of the problem –State of the environment –Growth and the environment –The environmental Kuznets curve Concepts of sustainability –Definitions, meanings, conceptualisations

2. Last week Introduction into the discipline The three themes: efficiency, optimality and sustainability Economy- environment interdependence The circular economy

3. The Quality of the Environment Pollution problems are not new to mankind Pollution control laws in Europe date back from the Middle Age What is new is the magnitude of the problem –Increasing size of population –Increasing per capita consumption of environmental goods and services

4. Environmental Problems: Air Acidification: Fossil fuel burning and intensive agriculture release acidifying substances, that falls as acid rain Ozone layer: CFCs destroy the ozone layer, increasing UV radiation Climate change: Fossil fuel burning releases carbon dioxide, which changes climate Urban air quality: Traffic emits all sorts of substances that affect health, buildings and plants directly or indirectly

6. Environmental Problems: Water Eutrophication: Nitrates and phosphate released by agriculture and industry alter competition between species Toxic releases: Industry releases all sorts of toxic substances Endocrine disruptors: Pseudo-hormones have a wide-range of applications, alter the behaviour and physiology of animals Depletion: Some countries already have too little water, others are rapidly depleting fossil sources Contamination by pathogens: drinking water is not safe

8. Environmental Problems: Land Soil erosion: Reduced vegetation cover makes that top soil gets washed away Desertification: Erosion, climate change, overexploitation gradually turns once fertile areas into deserts Salinisation: Overirrigation leads to the build up of salt in the soil Waste: Increasingly large areas are used for waste disposal

9. Environmental Problems: Nature Loss of nature: More land for living, industry, transport, agriculture and recreation implies less land for nature Loss of species: Destruction of habitat, overuse and other factors lead to local and global extinctions and loss of biodiversity Exotic invasions: Deliberate and unintentional transport of species imply new forms of competition between species

10. Resource Problems Depletion of resources: Human extraction of all sorts of minerals (copper, zinc) and fossil material (oil, water) exceeds their build up, implying that less and less of the stuff is left in the ground for future generations Waste: Human waste exceeds the assimilating capacity of nature, leading not only to accumulation but also to reduced assimilation

11. Population Growth More people, more food, more energy, more transport, more space, more everything Projections19952050 Western Europe447479 (446-512) USA297356 (320-400) SSAfrica5581059 (965-1159) China1362 1670 (1526-1826) South Asia12401845 (1737-1949)

12. Economic Growth Incomes have been growing at rates of up to 10% a year, although the average lies somewhere between 1 and 2 per cent a year, doubling incomes every 35-70 years Higher income implies higher consumption, higher production, more resource extraction, and more waste Improved technology, less constrained, more aware, care more, status

13. Environmental Kuznets Curve Kuznets Curve: Inequality first increases, then decreases with economic growth Environmental Kuznets Curve: Environmental degradation first increases, then decreases with economic growth Holds for some, not for all pollutants Local or global? Even if true, no reason for complacency!

14. Sustainability John Stuart Mill (1857) If the earth must lose that great portion of its pleasantness which it ows to things that the unlimited increases of wealth and population would extirpate from it, for the mere purpose of enabling it to support a larger, but not a happier or better population, I sincerely hope, for the sake of posterity, that they will be content to be stationary long before necessity compels them to it.

15. Sustainability -2 Bruntland report (WCED, 1987) Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs Wonderful, but what does this mean?

16. Sustainability = Weak sustainability –Non-declining utility –Non-declining production opportunities –Non-declining yields of resource services Strong sustainability –Non-declining natural capital stocks –Ecosystem stability and resilience A social construct All that, plus efficiency and equity

17. Non-declining utility Pezzey: utility should not fall Hartwick: consumption should not fall Solow: consumption should be constant Whose utility, consumption? What is utility, consumption? What time scale? Substitution is allowed

18. CtCt C(6) C MIN C SURV C(1) C(5) C(4) C(3) C(2) Consumption paths over time

19. Non-declining production opportunities Solow, Page Q = Q(L, K H, K N ) No assumption about what is consumption, utility Production for whom? What is production? What time scale? Substitution is allowed

20. Non-declining natural capital stocks Taken literally, this stops everything – no substitution is allowed In practice, some substitution and compensation must be allowed, but how much? Is spatial substitution allowed? Or, at what spatial scale? What stocks are maintained? Habitats, species, genes? What to do with viruses and pests?

21. Existing or optimal capital stock? KnKn B, C Kn*Kn* KeKe C (forgone development value) B (total economic value) KeKe

22. Non-declining yields of resource services Back to an anthropocentric viewpoint, or not? Depends on services to whom? To Homo Sapiens or to other species as well? What are services? What time scale? What spatial scale? Substitution is allowed, as long as the service is generated

23. Ecosystem stability and resilience An ecocentric viewpoint, or is it? Is stability measured as stably serving human needs? What is stability, resilience? What spatial and temporal scale? Are ecosystems naturally stable? Beyond a point, no substitution of man- made stocks and activities for natural stocks and processes

24. A social construct Sustainability is, of course, defined as society would like to define it Focuses on process rather than outcomes or constraints Propose consensus building through negotiations There is no objective definition possible Some argue that if only we get the procedure of defining sustainability right...