The urgent need to stabilise population numbers

2. The urgent need to stabilise population numbers Jenny Goldie Sustainable Population Australia inc president@population.org.au

3. Global population • Global population 6.48 billion • Still grows by over 70 million a year • 9 billion by 2050 – up to 12 billion • Most future growth in developing world • Growth variable – TFR 1.2 – 8 • Many low pop growth countries wealthy • Most high pop growth countries poor

4. Barriers to further growth • Ecosystem health • Food production • Climate change • Peak Oil

5. Ecosystem health Millennium Ecosystem Assessment: • Humans have changed ecosystems more rapidly and extensively in the last 50 years than in any other period • Ecosystem changes that have contributed substantial net gains in human well-being and economic development have been achieved at growing costs in the form of degradation of other services.

6. Ecosystem Health Millennium Ecosystem Assessment: • The degradation of ecosystem services could grow significantly worse during the first half of this century and is a barrier to achieving the UN Millennium Development Goals. • The challenge of reversing the degradation of ecosystems while meeting increasing demands can be met but require significant policy and institutional changes.

7. Food production • 800 million undernourished (hungry) with no money to buy available food • 3 billion malnourished • Many countries not self-sufficient in food • Total calorie production has kept pace with population growth thanks to oil crops, but… • per capita grain production has fallen for past two decades (380 to 330 kgs/person)

8. Food production • Yields still increasing but rate declining • Land gained from deforestation about equal to land lost to houses, roads & degradation • 10 m hectares annually lost to soil erosion • 10m hectares annually lost to salinisation • Quarter of all arable land - declining productivity

9. Food production • Little good land left to farm (maybe Brazil) • Cannot expect dramatic gains in yield • Diminishing returns (extra fertiliser doesn’t increase yields after a point) • Falling water-tables from over-pumping • Loss of farmland to ethanol • Loss of cropland and rangeland to erosion (desertification)

10. Food production • Average grainland world wide: 0.23h in 1950 0.11h in 2000 0.07h in 2050 (at 9b and no loss of land) • Decline in resources will lead to drop in living standards and ultimately conflict • “World food security could begin to eclipse terrorism as the over-riding concern of governments.” - Brown

11. China • Falling water tables, drying rivers and polluted water • Annual grain harvests dropping since 1998 • 1.4 b people - still growing 0.6% a year • Grain deficit (demand minus supply) 37.5 m tonnes this year • Imported $US14.3b farm produce half 2004 • Will soon import 30-50 m tonnes annually

12. Climate change UNFPA (2001) • increased severity and intensity of storms • flooding and soil erosion • accelerate the extinction of plants and animals • shift agricultural zones • threat to public health through increased water stress and tropical disease

13. Climate change IPPC: • 0.7 degrees C. increase last century • 1.4 – 5.8 degrees C. this century • Both adverse and beneficial impacts • Richer countries (temperate) enjoy some beneficial effects • Poorer countries (tropical) endure adverse effects

14. Climate change Unknowns: • Effects of increased CO2 in the field • Potential losses from pests and disease • Spatial variability in crop losses • Effects of extreme climate events on crops and livestock

15. Climate change • Global warming has already cut rice harvests by 10% for every 1 degree inc in night-time temperatures • Rice production needs to increase 1% annually to keep pace with demand….but • 3.5 degree rise this century would see rice yields decline another 30% • Modern strains of rice may be resistant to rising temperatures (IRRI – Philippines)

16. Climate change Rising seas • Half metre rise by 2100 will double number of people affected by flooding (to 100 m) • Coastal land and mangroves damaged • Severe implications for fish-stocks from a warming ocean (wind strength and ocean circulation will affect breeding and migration patterns)

17. Peak Oil • Global supplies will peak soon (Simmons) • Oil effectively gone in 40 years • Current production 85 mbd - 75 mbd in 2015 • Faster oil extracted, faster pressure dissipated • Overproduction leads to production collapse • New fields often poor quality (Kazakhstan) • Tar sands extraction very energy-intensive

18. Peak Oil Implications • Higher energy prices • Higher prices of transported goods eg food • Air travel and tourism adversely affected • Recession likely with inflation and high unemployment and consumer debt • Plastics, medicines, packaging, synthetic fabrics, road surfaces, cosmetics, detergents, fertilisers will become scarcer

19. Peak Oil Implications for agriculture: • 70% water used for irrigation • More expensive to pump water around • Uneconomic to pump from deep aquifers • Land converted back to dryland farms, meaning less food available • More expensive to drive modern machinery • Fertilisers and pesticides increasingly expensive, meaning lower yields

20. Population • Increased demand for food and water as population grows • Yet less food and water available because of higher energy costs • Already 1.1b without adequate water and 2.4m without adequate sanitation • Need to stabilise atmosphere with 60% reduction in GGE • Urgent need to reduce per capita demand in rich countries but lift poor out of poverty

21. Population • Need to lift yields to feed more people at very time it will be difficult to do so • Ecosystems already stressed so cannot take on new land to farm • May need to revert farms to forest to retain ecosystem services • Technology can help but will not allow business-as-usual • Only solution: rapid stabilisation then reduction of population