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Would Climate Engineering Provide a Response to Climate Change in Africa? THE DEBATE HAS JUST STARTED Dr Cush Ngonzo Luwesi (PhD) Lecturer Kenyatta University. Climate Engineering Conference 2014 ( CEC 2014) 19 August 2014, Berlin, Germany. Acts of Gods or Anthropocene ?.
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Would Climate Engineering Provide a Response to Climate Change in Africa? THE DEBATE HAS JUST STARTED Dr Cush NgonzoLuwesi (PhD) Lecturer Kenyatta University Climate Engineering Conference 2014 (CEC 2014) 19 August 2014, Berlin, Germany
Acts of Gods or Anthropocene? There arethree categories of water stress that would be exacerbated by climate change: (i) Too little (ii) Too much (iii) Too dirty(Kundzewicz, 2007) water crises are not about too little water…. but about managing water badly such that billions of people & the environment suffer badly. (Water Vision, 2000)
The Science Behind It Hulme et al. (2001) Predicted increase of temperatures versus decrease of precipitations during the year in most African countries under the low B1 scenario for Dec– Feb. and Jun-Aug May 2013 the world reached 400 ppm CO2 or 4oC (UNEP/ FAO, 2013)
Eventually….They Survived • RecentHolocene – ca. 2000 yrs BP to Present • Reconstitution and re-extension of dense tropical humid forests to the present limits • Probable diminution ou stop between 15th and 18thcentury (Little glacial age). • Recolonisation dynamicsexperiencedin several parts of central Africaduring 20thcentury Modern era corresponds to the recentHolocene The last glacial maximum- the Würmglaciation - ended there about 15,000 years and was featured by major climatic droughts in Africa (Maley & Brenac 1998). • Glaciationsare associatedwith important fragmentation of dense tropical humidforests and the extension of savanas (Doumenge, 2014)
Believers and Deniers of C.C. Agree on a PLAN “B”: The principle of largescalegeoengineering has been backed strongly in 2009 by Sir Martin Rees of the Royal Society, who concluded that it may be necessary to have a "plan B" if governments could only reduce too little GHG emissions or if it’s too late to do so.
Geo-Engineering initiatives aiming to tackle climate change by sucking CO2 directly out of the air or limiting the sunlight reaching the planet (i.e. adding aerosols into stratosphere) are ranked from less to highly contro- versial due to finance, feasibility and long term side effects on biological Lives Climate Ready Crops that reflect light and are drought resistant. Results : Highly Needed, Useful , Safe and Effective but may be fantastically expensive and water unfriendly in some ecosystems Artificial trees for sucking CO2 out of the air and burying it in the ground. Results : Needed, Useful , Safe and Effective but may be fantastically expensive and water unfriendly in some ecosystems Biocharfor burning then burying agricultural waste to the ground to increase soil carbon and reduce carbon dioxide emission. Results: Fairly safe and Effective but may likely exacerbate famine Carbon Capture and Storage (CCS) from coal or other fossil fuel power plants and then pumped underground. Results: Feasible but expensive and not needed because increasing the fuel needs of a coal-fired plant by 25%-40%. Perspectives of the Success of CE in Africa Ocean nourishment by growing biomass then burying it or dumping it in the sea to enhance biological productivity to remove carbon dioxide from the atmosphere. Results: Fairly cheap but ecologically damaging, Ineffective (because it can't be scaled up sufficiently) and likely to exacerbate famine. Dumping lime or calcium or magnesium silicates into the sea to react with carbon dioxide and reverse ocean acidification. Results: Fairly safe and Effective but Expensive due to the amount of quarrying required to produce the rocks
Prospective Assessment of CE Success Whitening clouds to reflect more sunlight, and spraying salt water into the air to precipitate rain. Results : Middling cheap, Middling useless and Middling dangerous Broadly speaking, the cheap and effective options are dangerous; the safe options are expensive or useless. This isn't always the case. Seeding the oceans with iron filings, for example, is probably both useless and dangerous. White Painting of buildings and roads and covering deserts in reflective plastic sheeting to reflect sunlight back into space and ensure that the earth absorbs less of the sun's heat. Results: Safe but Expensive and Useless Space mirrors to be sent into in orbit to deflect sunlight back into space. Results : considered unrealistic due to the scale needed, the expense and the potential unintended consequences
The Debate Has Just Started • A AS, SRMGI, EDF, The Royal Society and TWAS (August 2013). Governance of Research on Solar Geoengineering: African Perspectives - Consolidated Report of Three Workshops held in: • Dakar, Senegal, 27 June 2012 during the annual meeting of ANSTS • Johannesburg, South Africa, November 2012 during the at the South African National Conference on Global Change; and • Addis Ababa, Ethiopia, January 2013, during the the 24th Colloquium of African Geology (CAG24). • “SRM is an opportunity and we should not ignore it since Africa has made little progress to engage developed countries to subscribe to legally binding [GHG] agreements.” • “By coming up with SRM the West is seeking solutions for unanticipated results, i.e. a ‘plan B’ to solve the problem.” • “An independent global technical body must be responsible for assessing the risk of large scale SRM deployment before it can be considered.” • “Deployment of SRM should be heavily regulated. The injection of aerosols into the stratosphere should be regulated on a global scale by a global body.”
Think About This • Is CE capable of controllingthe global climate system? • What would prevent it from disturbing the climate system in Africa? • Do Geoengineers, Geocliques and Geokillers have the same degree of conscientiousness when it comes to the sacredness of human life? • What benefits/ risks does the African continent foresee from aerosols injections and carbons dioxide removal?
Think About This, Cont’D • What likely impacts can be foreseen from deployment of various CE technologies in different climatic regions of Africa? • What shall African scientists and leaders do to protect the huge ecological and biological systems of the continent in view of CE deployment? • What shall African scientists and leaders do to make their voice be heard and their position considered in the debate around CE?
Conclusion As Africans "We are going to have to look at new technologies which could suck CO2 out of the air. But we don't need to do this invest in harebrained schemes to reflect sunlight into space when we have no idea at all what impact this may have on weather systems around the globe”.(Mike Childs, head of science, policy and research at Friends of the Earth UK) “SRM should likewise be overseen by a newly formed institution, ideally with veto power resting on Africa and other countries most vulnerable to climate change.” (African Academy of Science et al., 2013) “The UN should take the responsibility of addressing SRM since poor climate change management can cause conflict.” (African Academy of Science et al., 2013)
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