Climate Change (natural & ‘unnatural’) … Past and Future Risks to Health

1. Climate Change (natural & ‘unnatural’) … Past and Future Risks to Health A.J. McMichael National Centre for Epidemiology and Population Health The Australian National University Canberra, Australia

2. Sexual activity CONVENTIONAL FRAME FOR ‘SOCIAL DETERMINANTS OF HEALTH’ Food choices Human behaviours Alcohol & smoking Individual health risks Social norms, ideology, knowledge; socio- economic equity Physical activity Marketing, social norms Road-use Production and processing systems: food, ‘substance’ items, cars, appliances, clothes Human culture History e.g. less (and nutrient-poor) food; water shortage; altered infectious disease patterns, morale & mental health disorders e.g. air pollution, contaminated food & water, agro-industrial effluent, endemic infections, social contact patterns, Built environment (cities, suburbs, roads, etc. Energy inputs Social conditions and relations Environmentally Sustainable (Remediable) local environmental pollution Community-level health risks Natural biophysical environment Managed biophysical environment Physico-chemical contaminants Mis-managed; excess demands Global environmental change/disruption (climate change, ozone depletion, soil loss, water depletion, biodiversity loss, etc.) Non-sustainable Populationhealth risks Overload of natural environmental systems

3. Australian Govt’s Climate Commission Report on “Climate Change and Health” Public launch in Sydney, Nov 28, 2012. First of the climate change impact reports, to be prepared by the Commission.

4. Variations in Average Northern Hemisphere Temperature, oC Rel. to 1960-80; Multiple palaeo-climatic sources, averaged +4 +3 +2 +1 +0.5 0 -0.5 -1 -2 -3 -4 Modelled temperature projection to 2100 – plus 3-4oC (?) Temperature variation around the smoothed graph, at half-decade scale, is approx. plus/minus 0.5oC Average Temp, oC (rel. to 1960-80) Holocene Climate Accelerated warming since 1975 Roman Warm Period Holocene Climatic Optimum, I & II Mediaeval Warm Period, Europe 17th Cent Crisis, Europe Sahara dries out Drought in Eastern Mediterranean region Cooling event Little Ice Age in Europe (similar in China) Post-glacial warming, (after transient rapid cooling due to Younger Dryas) Tambora eruption 1815 536 CE Event (acute cooling) 2-3oC fall 11 10 9 8 7 6 5 4 3 2 1 0 2 4 6 8 10 12 14 16 18 20 22 Millennia BCE Centuries CE 2000 yrs ago

5. “A Safe Operating Space for Humanity” Identifying & quantifying planetary boundaries that should not be transgressed Rockstrom et al. Nature 2009 Green = estimated safe operating space Climate change Nitrogen cycle Biodiversity loss

6. Global Annual Temperature, 1750-2010: The Rising Atmospheric CO2 Concentration, plus Sporadic Volcanic Cooling, Provides the Best Modelled Fit of the Actual Observed Temperature Trend Expected temp trend – modelled – due to increasing CO2 concentration, punctuated by sporadic volcanic cooling Post-1950s rise, mostly attributable to human actions (IPCC) Actual annual temperatures +1.5oC 1750-2010 Systematic thermo-meter use begins BEST Project, UC Berkeley, 2012

7. Regional Temperature Change over Past ~20 Years +4oC +3oC +2oC +2.5oC +1.5oC -0.5oC +1oC +2oC +1.5oC -1.5oC +1oC +1oC +1oC La Niña (ENSO): westward flow of cold surface water: warm water heaps up in western Pacific -1oC +1oC -1.5oC Difference from 1980-2010 average temperature -4oC 0 +4oC Adapted from: US Nat Oceanic & Atmospheric Admin (NOAA), State of Climate, 2011

8. Arctic Sea Ice Extent (millions km2), Sept 17, 2012 Median ice limit 1979-2000 Nth Pole Scandinavia Canada Greenland UK ± 2 standard deviations Atlantic Ocean 1979-2000 average 2007 2012 Source: National Snow and Ice Data Center, Boulder, Colorado

9. Annual Temperature Fluctuations in Western (alpine) Europe and Scandinavia, 450-650 CE: Evidence of abrupt cooling in 536-545 CE 2 0 -2 460 480 580 520 540 560 580 600 620 640 NOTE: temperature data are from seven different regional tree-ring data-sets. The data are de-trended over time, and the mean is set at zero. Temperature graph from: Larsen LB et al. (2008). Geophys. Res. Lett., 35, L04708. doi:10.1029/2007GL032450.

10. Aksum’s main trade routes, land and sea during 300-700 CE. ( red lines/arrows)

11. Europe’s coldest period, 1570-1660, during Little Ice Age Food yields down, grain prices tripled … conflict , war, displacement Cold Period 1570-1660 European Temperature Variation standardised units Nth Hemi-sphere Temperature Variation oC 1644 Famine-yrs/decade x 2 Epidemic rate x 3 Adult height ↓1.5cm Rate of Migrations, Europe War Fatality Index, Europe 1500 1550 1600 1650 1700 1750 1800 Zhang et al., PNAS, 2011

12. Climate Change and Human Health: Types of Health Risk Assessment (past, present, future) Scenario-based modelling: Estimating the range of future plausible risks Statistical study: Estimating the attributable burden of disease Temperature +2.0oC +1.5oC Empirical Studies: Risk per oC Empirical Observations: Attributable to climate change? 2050 1950 Now Natural temperature variation Modelled future temperature(s)

13. heatwaves, extreme weather events Direct impacts of heat: physiological, organ damage, behavioural Risk of injury and death shortages, prices: competition People Relocation Conflicts, displacement Climate Change ~ Other global/systemic environmental changes – coexisting with climate change temperature and rainfall Mean climatic conditions and Variability Glacier loss, sea-level rise Altered surface water Reduced food yields Ecosystem damage Property loss Infra-structure damage Tourism and recreation Physical hazards Direct economic impacts Loss of jobs, livelihoods River flows, Altered microbial ecology (host-animals, vectors, pathogen multiplication) Fresh-water availability Food prices, choices Community & family morale: mental health problems Household hygiene Local food yield Nutrition: child devt; adult health Infectious disease risks Post-event depression, etc.

14. Deaths Attributable to Climate Change: Year 2000 Estimated annual deaths due to climate change from: malnutrition (~80K), diarrhoea (~50K), malaria (~20K), flooding (~3K) 14 WHO statistical regions scaled by estimated annual mortality (in 2000) due to change in climate since c.1970. Selected major causes of death. (Patz, Gibbs et al, 2007: based on McMichael, Campbell-Lendrum, et al, 2004)

15. Climate Change Influences on Health in Australia Already apparent: preexisting risks amplified by climate change Uptrend in av annual no. of heat-days  deaths, hospitalisations Increase in no./severity bushfires  injury/death, resp. hazard, mental hlth Probable ongoing health impacts: butnot yet clearly identified Rise in some food-borne diarrhoeal diseases Altered air quality: ozone formation, aeroallergens Mental health impacts, esp. in some (drying) rural regions: e.g. MD Basin Predicted future health impacts Extreme weather events: trauma, infectious disease, depression Water shortages: affecting food yields, domestic hygiene Shifts in mosquito-borne infection patterns: Dengue, Ross River virus (& chikungunya?), Barmah Forest virus, Japanese encephalitis, etc. Thermal stress in outdoor workers: accidents/injuries, organ damage

16. Typical Relationship of Daily Temperature to Daily Death Rate in Temperate-Zone Countries High Daily Death Rate Comfort zone Low Source: McMichael, 2012 Daily Temperature (oC) Brisbane Melbourne Relative Risk of (daily) Death 22oC 24oC Daily Temperature (oC) Source: Huang, Barnett et al, 2012

17. Evidence of a Warming Australia Bureau of Meteorology: '2009 will be remembered for extreme bushfires, dust-storms, lingering rainfall deficiencies, areas of flooding and record-breaking heatwaves.' Australia’s 2009-2010 mean temperature was ~1°C above the 1961-90 average. 2010 Decadal mean temperature 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

18. Heatwaves, Illness Events, MortalityMelbourne, Australia, 2009 Ambulance call-outs for heat-related illnesses in Metropolitan Melbourne, 19 Jan-1 Feb, 2009 Temperatures 27-31 January 2009: max temperatures 12-15°C above summer norm. 28-30 Jan: > 43°C 50 45 40 35 30 25 20 15 10 5 0 250 200 150 100 50 0 Maximum Temperature Number of ambulance call-outs Temp oC Heat Stress Dehydration Heat Stroke Call-outs, deaths January 29-30: Great increase in ambulance call-outs 126 out-of-hospitaldeaths (vs. 44 expected deaths) Jan: 19 20 21 22 23 24 25 26 27 28 29 30 31 1Feb Date SOURCE: January 2009 Heatwave in Victoria: an Assessment of Health Impacts. State of Victoria 2009

19. Relationship of Salmonella gastro-enteritis occurrence to daily temperature, Sydney, 1990-2010 [26oC] As maximum daily temperature increases, the risk increase with min. daily temperature steepens [22oC] Relative Risk [19oC] Minimum Daily Temperature oC Source: Ainslie Butler, NCEPH/ANU, unpub

20. Dengue Fever: Estimated ‘receptive’ region for Ae. aegypti mosquito vector, under alternative climate-change scenarios for 2050 . . Darwin . Katherine . Cairns . . Broome . Townsville . Darwin . Port Hedland . Mackay Risk region for medium emissions scenario, 2050 . . Katherine Rockhampton . Cairns . Carnarvon . Broome Townsville . Port Hedland Mackay . . Current risk region for dengue transmission Rockhampton . Darwin . Brisbane . Katherine . Cairns . . Broome Townsville . Port Hedland . Mackay . Risk region for high emissions scenario, 2050 Rockhampton Carnarvon NCEPH/CSIRO/BoM/UnivOtago, 2003

21. Baseline 20002025 2050 Climate Change and Malaria Potential transmission in Zimbabwe Harare Climate suitability:* red = high; blue/green = low Low probability Highlands Medium probability High probability Bulawayo * Temperature + minimum seasonal rainfall Ebi et al., 2005

22. Baseline 20002025 2050 Harare Bulawayo Climate Change and Malaria Potential transmission in Zimbabwe Climate suitability: red = high; blue/green = low Ebi et al., 2005

23. CLIMATE CHANGE: Poor Countries Projected to Fare Worst MODELLED CHANGES IN CEREAL GRAIN YIELDS, TO 2050 20 36 • Plus climate-related: • Flood/storm/fire damage • Droughts – range, severity • Pests (climate-sensitive) • Infectious diseases (ditto) 80 64 Percentage change in yields to 2050 -50 -20 0 +20 +50 +100 UN Devt Program, 2009

24. 2050 A2 2100 A2 Source: P. Lehodey Now 2050 Skipjack tuna, Pacific Ocean 1,727,000 m tonnes/yr 2100 432,000 mt Loukos H, Monfray P, Bopp L, Lehodey P. (2003) Potential changes in skipjack tuna habitat from a global warming scenario: modeling approach and preliminary results. Fisheries Oceanography, 12(4): 474-482

25. CH4 CH4 CH4 CH4 Brrrp CH4 Adaptation and Mitigation Adaptation: Risk management Time-frameOptions: - Immediate protection (heatwave warnings, dams/sea-walls) - Long-term protection (urban design/greening,resilient rural communities, vaccines) Priority/equity (who is vulnerable?) Evaluate (cost-effectiveness?) Mitigation … and itsHealth Co-Benefits to local population -Cleaner urban air: ↓cardio-resp disease - More walking/cycling:  fitness, social contact - Healthier climate-proof insulated housing - Diet: local fresh foods less (ruminant*) red meat ↓obesity, cardiovasc disease, some cancers * cattle, sheep, goats, camels, buffaloes

26. Three Key Messages • 1. Human-induced ‘climate change’ is real, increasing … and quite distinct from ‘local envtl pollutants’ in the type, range and significance of health impacts • 2. Health professionals will, increasingly, encounter changing rates of differential diagnoses, emergency hopital admissions, enquiries from concerned public • 3. Health sector will need to adapt (continuously) by: • -- Understanding climate-related exposures and risks • -- Curbing the sector’s greenhouse emissions • -- Upgrading/changing community surveillance practices • -- Working more closely with other sectors • -- Assisting with public education, and political advocacy

27. That’s All

28. “… between 5-30% of the decrease in sea ice is due to the Atlantic Multi-decadal Oscillation …[which] implies that 70-95% of the changes are caused by human-induced global change."JJ Day, Univ. of Reading, July 2012 40 Total Arctic Sea-Ice Volume (1000 km2) 30 1979-2011 average 20 (av.1979-2011) 10 (2012) Adapted from: Polar Science Center (Univ. Washington), 2012 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

29. Estimated age-standardised incidence rate per 100,000 Melanoma of skin, both sexes, all ages ≤0.4 30oN ≤ 40 30oS < 0.4 < 0.8 < 1.6 < 3.9 < 36.7 Source: IARC, 2008. Globocan http://globocan.iarc.fr, accessed on 20/08/2012