Sustainability a global outlook

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1 Sustainability a global outlook Humberto D. Rosa hdrosa@fc.ul.pt Univ. of Lisbon, Faculty of Sciences Secretary of State of the Environment

2 Sustainability a global outlook Summary human development versus sustainability time as a dimension of sustainable development biodiversity versus sustainability energy versus sustainability climate change versus sustainability some dilemmas of sustainability 2

3 Human development human development is an apparent case of success a species expanded to all continents ten thousand times more abundant than expected from its size using about half the total production of all plants many expending as much energy and resources as a sperm whale 3

4 but where is it leading us? climate crisis biodiversity crisis ocean crisis fuel crisis food crisis finantial crisis What may all this mean? 4

5 Historical background Was there a sustainable golden age in our past? evidence of ancient and wide impacts of human expansion: North America, Australia, New Zealand, Madagascar, Pacific Islands, Greenland... few exceptions 5

6 Is human development sustainable? expansion = extinction no inate tendency to reach sustainability civilizational declines for environmental reasons What if the scale is now global? 6

7 The meaning of global unsustainability What is at stake? the planet Earth? life on Earth? humans as a species? or what?... 7

8 The time dimension of sustainability in 4-5 billion years the sun will inflate and turn a red giant Earth s water and most of its atmosphere will be boiled away then the sun will turn a white dwarf and cool 8

9 The time dimension of sustainability at cosmic time scale nothing on Earth is sustainable at short time scale everything may be sustainable what may be the adequate time unit for sustainability? 9

10 The case of biodiversity increase with time periods of mass extinction followed by recovery In what time scale? 10 My to start 20 to 100 My for full recovery So, is biodiversity renewable? 10

11 The time scale of human sustainability not millions of years! years? decades? centuries? millennia? proposal: 1000 years as a unit to measure human sustainability 11

12 The case of energy most energy available for human use is of solar origin sun, biomass, biofuels, hydro, wind, waves and fossil fuels too, they are solar energy captured by plants in the geological past 12

13 Why isn t oil sustainable? renewability as a key for sustainability the time dimension of renewability 13

14 Will there be sustainable, clean coal? will carbon capture and storage solve it? 14

15 Biomass, biofuels can they be sustainable? or not quite so? 15

16 Hydro reversibility as a further key for sustainability 16

17 Geothermal power renewable energy, isn t it?... but modified nuclear energy, isn t it?... 17

18 Nuclear clean? renewable? reversible? sustainable? 18

19 Wind clean? renewable? reversible? sustainable? 19

20 Waves clean? renewable? reversible? sustainable? 20

21 Solar clean? renewable? reversible? sustainable? 21

22 The future for sustainable energy Big production for big consumption? 22

23 The future for sustainable energy or small solutions for disseminated production and consumption? Microgeneration small scale production of heat and/or electricity from a low carbon source includes solar (photovoltaic or thermal), micro-wind, micro-hydro, heat pumps, biomass, small scale fuel cells 23

24 The future for sustainable energy renewable at adequate human scale clean, with reduced environmental impact with reversible solutions fair, accessible to all with a small scale pattern of production/consumption used efficiently 24

25 Climate change why worry? The first photosynthetic beings emerged in a world with a very different atmosphere than today. It was their activity that led, afther millions of years, to the accummulation of a waste product oxygen, resulting in a global atmosphere change. That change had a catastrophic effect in the initial biodiversity, which was adapted to a non oxydative atmosphere. At the same time, that was what allowed for the emergence of the biosphere and biodiversity of today, including humankind. If global change has occurred in the geological past several times, why should we worry with global change only because it is now caused by humans? 25

26 An ordinary map of the world 26

27 A population map of the world 27

28 An energy consumption map of the world 28

29 A greenhouse gas emissions map of the world 29

30 Some dilemmas of sustainability can there be sustainable growth? can human capital replace natural capital? how should nature be valued? which interests and options of future generations should count? can global sustainability be reached without global equity? can global sustainability be reached without global governance? 30