1. Science and decision-making Ian Lowe 21 May 2007

2. Ian Lowe2

3. Projected global warming

4. Ian Lowe4 An example of non-linear change Millennium Assessment Report 2005

5. Ian Lowe5 Possible non-linear changes North Atlantic circulation Methane from Arctic tundra Melting of [polar] ice Drying of rainforests Clearing and burning of peatlands

6. Ian Lowe6 What is “dangerous” climate change ? Two degrees of warming might be dangerous Three degrees almost certainly is

7. Ian Lowe7 How close is this ? Current CO 2 380 ppm With other GHG, ~ 460 ppm CO 2 equiv 510 ppm, 67 % chance warming > 2 0 590 ppm, 90 % chance warming > 2 0

8. Ian Lowe8 UK Government estimates 2003: 550 ppm, temperatures are expected to rise between 2 and 5 0 C 2006: “a limit closer to 450ppm or even lower might be more appropriate to meet a 2 0 C stabilisation limit”

9. Ian Lowe9 “If emissions and concentrations grow according to mid-range projections… the cumulative warming by 2100 would be approximately 3 o to 5 o C above pre- industrial conditions… scientific evidence suggests that changes of this magnitude are likely to be associated with large and perhaps abrupt changes in climatic patterns … will adversely impact agriculture, forestry, fisheries, availability of fresh water, the geography of disease, the liveability of human settlements…”

10. Ian Lowe10 0 200 400 600 800 1000 1200 1990200020102020203020402050 EnergyTransportFugitive, waste and industrial processes) AgricultureLand clearing Kyoto target 60 - 90% reductions Business As Usual Source: Adapted from the Australian Greenhouse Gas Inventory and ABARE projections Australia’s Emissions (Mt) Where we are going What we need to achieve

11. Ian Lowe11 It’s Achievable and Affordable Source: The Allen Consulting Group (2006) Real GDP ($b 2005)

12. Ian Lowe12

13. S O C I E TY E N V I R T

14. Ian Lowe14

15. S O C I E T Y E C O N O M Y E C O L O G Y

16. Ian Lowe16 Conclusion Even when the science is clear, decision-makers will tend to focus on the economy Science can inform and shape the policy debate: CFCs, water ? Forests ?? Scientists need to be policy - literate Policy-makers must be science- literate

17. Ian Lowe17 Photo: NASA