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Geoengineering

Geoengineering. Hadi Dowlatabadi January 29 2007 hadi.d@ubc.ca. Overview. What is the challenge? What are our options? What is geoengineering? What’s next?. Have you Noticed Climate Change Related to Global Warming?. Globe & Mail 27/01/2007.

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Geoengineering

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  1. Geoengineering Hadi Dowlatabadi January 29 2007 hadi.d@ubc.ca

  2. Overview • What is the challenge? • What are our options? • What is geoengineering? • What’s next?

  3. Have you Noticed Climate Change Related to Global Warming? Globe & Mail 27/01/2007

  4. Is Global Warming Occurring Due to Human Activity? Globe & Mail 27/01/2007

  5. Are Consumers or Industry to Blame for Most Carbon Emissions? Globe & Mail 27/01/2007

  6. Are Greenhouse Gases the Same Issue as Smog? Globe & Mail 27/01/2007

  7. Can Global Warming Be Solved? Globe & Mail 27/01/2007

  8. Intervention CC Completely Solved 12% CC Partially Solved 70% Not Solved at all 15% Don’t Know & no answer 3% Mitigation Emissions & other forcing factors > 2 GtCeq/yr e.g., Kyoto: ~ 5% reduction in CC by 2050 Adaptation to reduce impacts from remaining ~95% CC residual CC impacts not solvable by adaptation Geoengineering Iff some adverse effects of CC are less tolerable ... Outcomes

  9. Outcome Extraction of Services Modify the Earth System Acts Agriculture intentional unintentional Fossil energy intentional unintentional Hydro dams intentional unintentional Wind power intentional unintentional Geogengineering intentional Human Activities & Geoengineering

  10. Impacting the Earth System • Unintended impacts have been large enough to change climate. • Those who hold fast that climate change is “mostly” natural believe human activity is on too small a scale (compared to nature) to have brought about global change. • The potential to impact is determined by the rate of extraction cf. rate of renewal • fresh water ... • wind power ...

  11. A Short History of Intentional GeoEngineering • 1905 virtue of CO2 emissions warming the earth, extending agriculture pole-wards and increasing food production. • Russia • 1932 the Soviet Union took climate modification seriously, experimenting with cloud seeding. • 1961 USSR conducts an experiment that cleared away clouds from a 20,000 km2 area. • They were seeking to destroy arctic ice cover. • US • 1957 worry about strategic advantage of USSR. • 1960s well funded programs focus on weather modification. • 1966 started extensive cloud seeding in VIetnam • International • 1972 convention against military modification of environment.

  12. Intolerable? Antigua and Barbuda Marshall Islands Bahamas Mauritius Barbados Nauru Belize Niue Cape Verde Palau Comoros Papua New Guinea Cook Islands Samoa Palau Kiribati Nauru Florida Keys Grenada St. Vincent and the Grenadines Guinea-Bissau Suriname Guyana Tonga Haiti Trinidad and Tobago Jamaica Tuvalu Kiribati Vanuatu Maldives Cuba Singapore Cyprus Seychelles Dominica Sao Tome and Principe Dominican Republic Solomon Islands Fiji St. Kitts and Nevis Federated States of Micronesia St. Lucia

  13. Florida +6m Sea Level Rise

  14. Unimaginable? • The Trinity test was conducted while there were doubts about the potential for an A-bomb to set off an atmospheric chain reaction. Image courtesy of US Govt. Defence Threat Reduction Agency

  15. Geoengineering Options • Change balance of solar radiation • in space • in the upper atmosphere • by surface modification • Change carbon release to the atmosphere • through sequestration of captured CO2 • Change carbon uptake (... life of other GHGs) • in oceans and land through modified ecosystems

  16. Blinds in Space At L1, the angle of scatter needs to be ~ 0.01 rad ~3x103 t mass

  17. Sails in Orbit In earth orbit, the angle of scatter needs to be ~ 1 rad ~3x105 t source: http://antwrp.gsfc.nasa.gov/apod/image/0303/solarsail_msfc_m.jpgext

  18. More Persistent Clouds source: http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=3120

  19. Modelling Results • Gavindasamy & Caldeira (2000, GRL) modelled a 1.8% reduction in solar constant. • In 2xCO2 run 97% of surface temperatures were significantly different to control. • In 2xCO2+Geoengineering, 15% of pixels on earth had significantly different temperature and seasonal patterns were not different to control. • Budyko (1950s) • ~107 tSO2 in stratosphere counters 2xCO2 forcing. • Jet travel in 2005 led to 250MtC of CO2 emissions. If we use 2% S fuel dispersal will be free.

  20. Teller et al. • 105 t of metallic mesh-structure particles enough to increase albedo by 1%. • If made of Aluminium they would have long shiny life in stratosphere but oxidise in troposphere. • Thickness of wires is determined by optical depth in metal (20 nm) and mesh spacing has to be 1/2 the wavelength of scattered light we plan to scatter (300 nm). • Not cheaper than sulphur in jet fuel, but far lower in inadvertent impacts. http://www.filmnight.org/images/Strange2.JPG

  21. Ocean Fertilisation source: http://science.hq.nasa.gov/oceans/images/seawifs_carbon.jpg

  22. Pump It Down • Redfield studies molar ratio of elements making up living tissue. was identified by Redfield • C:N:Si:P found consistently in the ratio of 106:16:15:1 • Much of ocean N-limited, and many N-fixers are limited by availability of Fe. • C:Fe = 10,000:1 • IronEx I, II, III in the 90s led to a commercial venture that aims to increase fish production and cash in on the GHG offset market. • I can’t find any of the papers or data on these any more!

  23. http://geography.berkeley.edu/ProgramCourses/2003_Field_Pictures/SouthCoast/0304_Serpentine.jpghttp://geography.berkeley.edu/ProgramCourses/2003_Field_Pictures/SouthCoast/0304_Serpentine.jpg Lock It Up • Geologic weathering provides the material for normal sequestration of CO2. • CO2 has an exothermic reaction with serpentine rocks (MgSiO3). • In principal, power-plants can separate CO2 and react it with serpentine. • The volume of material needed is similar to the volume of fossil fuels being consumed. • This is a very costly option both in economics and in disturbance to the environment.

  24. Geoengineering Energy Balance Energy Transport Short Wave Albedo Long Wave Emissivity Ocean Atmosphere & Surface Goals space & atmospheric scatterers surface albedo uptake of CO2 and conversion of other GHGs. changing ocean salinity/turnover changing: rate of evaporation Surface roughness Means aerosols deforestation build surfaces afforestation GMO enhanced photosynthesis OH- for CH4, O+ for N2O large dams (Gibraltar) OTEC iceberg transport surface treatments wind turbines Cost ~50 B - ~300B to offset 2xCO2 x10~100 ? ?

  25. More than Climate is Changing • We are changing: • atmospheric composition, chemistry & physics • ocean chemistry and circulation • surface albedo and roughness • If we want to reduce impacts, we should consider efforts that look beyond reducing forcing and reduce change in composition of the atmosphere.

  26. CO2 Capture: Sleipner, Norway www.statoil.com/.../ $FILE/sleipner.jpg www.statoil.com/.../ $FILE/sleipner.jpg

  27. No Black Magic in Amine Process R2NH + CO2 ⇔ R2NCOO- + H+ R2NH + H+ ⇔ R2NH2+ CO2

  28. Below The Waves

  29. CO2 Injection Enhanced oil recovery using CO2 injection has been used for 3 decades.

  30. Even in Florida http://www.princeton.edu/~hotinski/Resources/NETL_tampa_gasification_large.jpg

  31. CO2 Reservoirs & Leaks!

  32. Reservoir Sizes • Geological • Depleted oil and gas reservoirs: 200-500 GtC • Deep saline aquifers: 102-104 GtC • Deep coal beds: 100-200 GtC • Chemical reaction with Silicate rocks. • Oceanic • Capacity is large: ~ 103-104 GtC; depending on the “acceptable” degree of acidification. • Atmosphere-ocean carbon equilibrium: ~80% in ~300 years.

  33. Renewables: Biomass • Average power use in more industrial countries: • 5kW/cap. • Range of energy capture in terrestrial systems: • 0.2 - 2 Wm2 • Area needed to meet all needs for average person: • 0.5 hectare/capita = 1/2 of (croplands + forests)

  34. Electricity: GHG vs. Cost tCO2/Gj ¢/kWh

  35. Cost 0 0 50 100 % Climate Change Averted Cost to Intervene Mitigation CSS Geoengineering

  36. Option $/tC Risk Stratospheric SO2 <<1 Atmospheric chemistry Solar Shields 0.05-0.5 Does not address other impacts of CO2 increase Ocean: Iron 1-10 Is Fe really limiting?can this be a long-term solutions? Ocean: Phosphate 3-10 Oxygen depletion, ecological shift, long term capture questionable Intensive forestry 10-100 Biodiversity and soils. CO2 in ground 50-150 Low CO2 in ocean 50-150 Moderate uncertainty about fate Cost of Mitigation

  37. Policy • A shot-gun marriage between: • the available • AND • the imperative

  38. Earth of tomorrow?

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