C hange: M igration and A daptation (DECCMA) Robert J. Nicholls, - - PowerPoint PPT Presentation
DE ltas, vulnerability and C limate C hange: M igration and A daptation (DECCMA) Robert J. Nicholls, University of Southampton THREATENED DELTAS With Sea-level Rise and Subsidence Nile and Ganges-Brahmaputra Deltas (Broadus et al., 1986);
Robert J. Nicholls, University of Southampton
Nile and Ganges-Brahmaputra Deltas (Broadus et al., 1986); Milliman et al ., 1989)
People displaced by 2100 (2012 population): 16 to 20 million (Egypt) 42 to 54 million (Bangladesh)e
(Ericson et al (2006); IPCC AR4, 2007) Population potentially displaced by current sea-level trends to 2050 (Extreme >1 million; high =1 million-50,000; medium 50,000–5,000 people)
Global population in deltas is about 500 million people
Lecture 4. Climate change and the integrated coastal system. Wednesday 25 July 2007
Lecture 4. Climate change and the integrated coastal system. Wednesday 25 July 2007
River Floods/ Sediment Supply Changing catchment management
Taking Bangladesh as an example
1. to understand the governance mechanisms that promote or hinder migration of men and women in deltas; 2. to identify climate change impact hotspots in deltas where vulnerability will grow and adaptation will be needed; 3. to understand the conditions that promote migration and its
trapped populations, via surveys; 4. to understand how climate-change-driven global and national macro-economic processes impact on migration of men and women in deltas; 5. to produce an integrated systems-based bio-physical and socio-economic model to investigate potential future migration under climate change; 6. to conceptualise and evaluate migration within a wide suite of potential adaptation options at both the household and delta level; 7. to identify feasible and desirable adaptation options and support implementation of stakeholder-led gender-sensitive adaptation policy choices.
Population potentially displaced by current sea-level trends to 2050 according to Ericson et al (2006)
Extreme >1 million; high =1 million-50,000; medium 50,000–5,000 people
a b c d (a)Ganges-Brahmaputra delta, Bangladesh/India; (b)Manhandi delta, India; (c)Nile delta, Egypt; (d)Volta delta, Ghana
GBM Delta, Bangladesh and India Nile Delta, Egypt Mahanadi Delta, India Volta Delta, Ghana Rivers/catchmen t area (103 km2) Ganges, Brahmaputra, Meghna (1,730) White and Blue Nile (3,870) Mahanadi, Brahmnai & Baitarani (141) Black Volta, White Volta and Red Volta (398) Size of delta (103 km2) 87.3 (66% in Bangladesh; 33% in West Bengal, India) 24.9 5.91 2.43 Annual (and peak) discharge (m3/s) 35,500 (138,700 - average annual peak) 2,830 (NA -- Aswan Dam) 1800 (45,000) 900 (NA -- dam at Akosombo) Sediment input (tonnes/yr) 1 x109 Negligible since dam construction (see below) 29.8 x 106 Negligible since dam construction (see below) Catchment interventions Significant, but less affected than other three deltas High Aswan Dam in 1964 stopped all upstream influence Hirakud Dam in 1957 Akosombo Dam (1961- 1965) stopped all upstream influence Current RSLR (mm/yr) 11.0 4.4 3.3 3.0 Key current land issues and hazards Floods, erosion, low dry season availability, water logging, salinisation, storm surge Urbanisation (everywhere), widespread salinization Floods, erosion, low dry season availability, water logging, salinisation, storm surge Erosion (especially at Keta), floods, salinisation Typical crops Rice (main crop), wheat, jute, pulses, oilseeds, sugarcane, potatoes, vegetables, spices Rice, maize, wheat, tomato, alfalfa Rice (main crop), wheat, jute, pulses, oilseeds, sugarcane, potatoes, vegetables, spices Shallot, maize, cassava, tomatoes, okro, yams and rice. Delta population (x106 people) 111 47.8 3.88 0.38 Typical livelihoods Agriculture, fisheries, urban workers/labourers, mangroves (Sunderbahns) Rural areas -- agriculture and fisheries; Urban -- industry and services Agriculture, fisheries Fisheries, agriculture and salt production Main cities in delta Khulna, Kolkata Alexandria, plus 13 other cities Bhubaneswar, Cuttack and Puriare Accra (not in delta)
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Robert J. Nicholls, University of Southampton