Impacts and Adaptation in Key Sectors

1. Impacts and Adaptation in Key Sectors Nick Brooks nb@garama.co.uk www.garama.co.uk

2. Food and agriculture 2

3. Climate (change) shocks and price spikes • 2010 floods in Pakistan, world’s 4th largest cotton producer • Shock to markets facing low supplies & rising prices - panic buying by mills • UN & Pakistan government invoked climate change as major contributor to floods • Longer-term risks related to climate change impacts on water availability • Adaptation by producers (water management) & in supply chains (diversity of sources) Information & graphic from: Thorpe and Fennell 2012. Climate Change Risks and Supply Chain Responsibility. Oxfam Discussion Papers. http://www.oxfam.org/en/grow/policy/climate-change-risks-and-supply-chain-responsibility 3

4. Potential impacts on crop yields • As result of changes in rainfall, temperature, low-level ozone, pests, diseases, extreme events, etc – these will interact in complex manner • Impacts likely to be particularly great for maize and wheat(Challinor et al. 2010; Hertel et al. 2010) • Suggested temperature-induced crop yield losses of 2.5-16% per 1° C(Battisti & Naylor 2009) • Low-level ozone could reduce yields by ~10s of % by 2050(Long et al., 2005) • Overall reductions of 8-22% across 5 crops in from one study(Schlenker & Lobell 2010) • Increased capital & labour might offset losses to 2030, then more difficult(Bezabih et al. 2010) • Livelihood impacts complex - e.g. increased food prices will mean greater economic stress but also increased opportunities for investment etc. (Hertel et al. 2010) • Still much uncertainty, and impacts will depend on extent of adaptation 15

5. Effects of rainfall & temp on crop yield (IPCC 2014 AR5 SPM)

6. Ranges of projected changes in crop yields for Africa • Large variations depending on model, methodology, assumptions • Uncertainty in future rainfall helps explain some of range • Extent to which adaptation represented is also key • Study based on current systems & practices From Müller et al. 2011: Climate change risks to African Agriculture, PNAS: www.pnas.org/cgi/doi/10.1073/pnas.1015078108 16

7. Changes in yield, 2046-65 relative to 1961-2000, from Schlenker & Lobell, 2010. Ranges span results from 16 models, under medium emissions A1B scenario Without adaptation or expansion of irrigation, based on current fertilizer use. Rice & wheat excluded as widely irrigated but irrigation data sparse; irrigation effects would heavily bias results. 17

8. As previous slide, effects of temperature & precipitation disaggregated (Schlenker & Lobell, 2010): changes in temperature much more important than rainfall 18

9. Same study as previous slides (Schlenker & Lobel, 2010), showing predicted changes in maize yields at the country level, compared with results from other studies • Assume no change in seasonal activity, which could be potential adaptation • More “optimistic” studies may include adaptation measures/assumptions, including investments, irrigation, more inputs e.g. labour & fertilizer, etc 19

10. Changes in growing seasons • For maize, millet & sorghum, expected changes in growing season temperatures much more important than expected changes in rainfall • Many areas will have growing season climates very different to those of today Percentage overlap between historical and 2025 (left), 2050 (middle), and 2075 (right) simulated growing season average temperature at over African maize area. Dark blue colors represent 100% overlap between past and future climates, dark red colors represent 0% overlap. From Burke et al. 2009. Global Environmental Change 19: 317-325 20

11. Impacts on growing seasons Future growing season temperatures mostly outside today’s range – “novel” growing climates Future growing season temperatures similar to today in most of country Percentage overlap between current (1993-2002) distribution of growing season temperatures within a country and simulated 2050 distribution of temperatures in the same country. Black: maize; grey: millet; white: sorghum. From Burke et al. 2009. Global Environmental Change 19: 317-325 From Burke et al. 2009. Global Environmental Change 19: 317-325 21

12. Will ‘novel’ 2050 growing climates in a given country have present-day analogues in other countries? Many countries whose current climate is analogue for future climate Few countries whose current climate is analogue for future climate Countries facing novel climates with few/no analogues - how to adapt? Small changes in growing regimes within countries Adaptation through international movement of germplasm & shifts in cultivation within countries Adaptation through international movement of germplasm Source: Burke et al. 2009. GEC Large changes in growing regimes within countries From Burke et al. 2009. Global Environmental Change 19: 317-325 22

13. Adaptation options for agriculture • Capital & labour investment, resilience building in near-medium term • Strong focus on water (& soil) conservation & water harvesting • Careful expansion of irrigation informed by water availability projections • Intensification in most productive areas (caution on expansion into new areas) • Development of drought and disease/pest resistant & faster growing strains • Movement of germplasm & adoption of exogenous practices • Urban agriculture using runoff & waste water • Phased relocation of agriculture based on in-country analogues Wheat rust and innoculation. Images from CIMMYT via Flickr Creative Commons license. See also http://blog.plantwise.org/2011/04/27/wheat-rust-and-climate-change-%E2%80%93-a-possible-connection/ 13

14. Transitions from farming to herding? • Marginal areas where rainfall close to limit for rain-fed agriculture & irrigation not viable, or where increased irrigation demand cannot be met • Support livelihoods based on extensive pastoralism • Add value to pastoral products • Markets, access, communications, mobility • Generally would require significant policy shift Graphic from Jones & Thornton 2009; 24

15. Impacts on livestock • Uncertain impacts on feed crops, rangeland composition/productivity, pasture quality • CO2 fertilisation – different across plant types, species, geographical regions • Interacts with (limited by) changes in rainfall, temp., variability, esp. in (sub)tropics • IPCC suggests +ve impact of 2° C warming in humid temperature regions, -ve impact in arid & semi-arid regions • Higher temperatures: possible ceiling on dairy milk yield, reduction in fertility • Suggests more work needed on CC impacts on rangelands, warming impact on livestock health, fertility & productivity, for different livestock varieties/contexts • Climate risk assessments to identify high risk areas & potential impacts, particularly for initiatives to expand farming based on temperate climate species (e.g. dairy) • Rangeland monitoring will be crucial in understanding risks & livestock potential Thornton et al. 2009. Agricultural Systems 101: 113-127 25

16. Adaptation in the coastal zone 16

17. Sea-level rise projections Left: Latest projections for different Representative Concentration Pathways, from IPCC AR5, SPM. Right: Sea level observations to 2009 and projections to 2100. Shaded light blue zone represents IPCC AR4 A1F1 scenario. Coloured bars represent more recent estimates including Rahmstorf, 2007 (red); Grinstead et al., 2009 (green); Vermeer et al., 2009 (dark blue). From Nicholls & Cazenave 2010. • Survey of expert opinion gave range of 61-73 cm by 2100(Science 2011 vol. 334, p.1616) • Very recent study 48-112 cm for B1 scenario, with mid-range around 75 cm (Orlić and Pasarić 2013) • Rates of SLR during past interglacial were ~1.6m century (Rohling et al. 2008) 13

18. Mapping exposure - example

19. Tropical storms Expected changes in tropical storm behaviour (frequency, category 4-5 frequency, intensity, precipitation rate) for 2081-2100 relative to 2000-2019, based on expert judgment interpretation of models. Blue lines represent ‘best guess’. IPCC 2013 AR5 WG1, Ch.14, Figure 14.17, p.133. 19

20. Ocean acidification • Increased atmospheric CO2 – more CO2 absorbed by oceans making them more acidic • Affects ability of certain organisms to build carbonate shells & exoskeletons • Different species respond/adapt differently to increased acidity • Acidity acts in conjunction with warming (e.g. bleaching) & other stresses • Worst-case scenario: large-scale collapse of marine ecosystems & corals • Best-case scenario: changes in ecosystem composition & functioning, changes in ranges & abundance of key species (e.g. economically important fish stocks etc.) Explorers’ Cove, Antarctica. Photo: Courtesy of Shawn Harper via Argonne National Laboratory, Flickr Creative Commons 20

21. Hazards & impacts in coastal zones 21

22. Adaptation measures in coastal zones • Building resilience & adaptive capacity - livelihoods & disaster recovery • Improved early warning systems • Rezoning to reduce exposure, changes to building standards • Reduce stresses on coastal & marine ecosystems to make more resilient • Rehabilitation of coastal ecosystems (e.g. mangroves) as buffer • Beach/dune nourishment to protect / extend lifetime of beaches & near-shore • Managed realignment - allowing coastal systems to migrate with sea-level rise • Hard protection measures - sea walls, breakers to dissipate wave energy • Phased relocation - people, infrastructure, economic activities • Risk mapping for adaptation support (e.g. flood risk) • Watershed management, ICZM frameworks

23. Types of adaptation • In both sectors discussed above, there is significant scope for ‘incremental’ adaptation or ‘climate proofing’ of existing systems & practices • However, transformational adaptation will also be needed, and importance of this option likely to increase over time • In case of sea-level rise & low-lying coastal areas, building resilience & incremental adaptation will only be viable for so long • [Without action to remove CO2 from atmosphere we are probably committed to a long-term rise in global mean sea level of 20-30m, based on past analogues] • In case of agriculture, likely to see large changes in availability and distribution of water and productive land in medium to long term Elevations above mean sea-level for West Africa )(left) and SE Asia (right) – orange to yellow transition is ~10m, i.e. low-evelation coastal zone Grinding stone, Erg Uan Kasa, Central Sahara: legacy of ‘green Sahara’ ~5000-10,000 yrs ago

24. Concluding thoughts – a long-term perspective Glacial cycles and aridity Grassland Extreme desert 9,000 years ago 21,000 years ago Palaeovegetation maps by J. Adams (Oak Ridge Nat. Lab., USA) http://www.esd.ornl.gov/projects/qen/nercAFRICA.html 5

25. Concluding thoughts – a long-term perspective Glacial cycles and aridity Grassland Present day 9,000 years ago Palaeovegetation maps by J. Adams (Oak Ridge Nat. Lab., USA) http://www.esd.ornl.gov/projects/qen/nercAFRICA.html 5