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©2009 Dowlatabadi Geoengineering Hadi Dowlatabadi January 29 2007

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Presentation on theme: "©2009 Dowlatabadi Geoengineering Hadi Dowlatabadi January 29 2007"— Presentation transcript:

1 ©2009 Dowlatabadi Geoengineering Hadi Dowlatabadi January 29 2007

2 ©2009 Dowlatabadi 2 Overview What is the challenge? What are our options? What is geoengineering? Whats next?

3 ©2009 Dowlatabadi 3 Have you Noticed Climate Change Related to Global Warming? Globe & Mail 27/01/2007

4 ©2009 Dowlatabadi 4 Is Global Warming Occurring Due to Human Activity? Globe & Mail 27/01/2007

5 ©2009 Dowlatabadi 5 Are Consumers or Industry to Blame for Most Carbon Emissions? Globe & Mail 27/01/2007

6 ©2009 Dowlatabadi 6 Are Greenhouse Gases the Same Issue as Smog? Globe & Mail 27/01/2007

7 ©2009 Dowlatabadi 7 Can Global Warming Be Solved? Globe & Mail 27/01/2007

8 ©2009 Dowlatabadi 8 Outcomes Intervention CC Completely Solved 12% CC Partially Solved 70% Not Solved at all 15% Dont Know & no answer 3% MitigationEmissions & other forcing factors > 2 GtC eq /yr e.g., Kyoto: ~ 5% reduction in CC by 2050 Adaptationto reduce impacts from remaining ~95% CC residual CC impacts not solvable by adaptation GeoengineeringIff some adverse effects of CC are less tolerable...

9 ©2009 Dowlatabadi 9 Human Activities & Geoengineering Outcome Extraction of Services Modify the Earth System Acts Agricultureintentional unintentional Fossil energyintentional unintentional Hydro damsintentional unintentional Wind powerintentionalunintentional Geogengineeringintentional

10 ©2009 Dowlatabadi 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 ©2009 Dowlatabadi 11 A Short History of Intentional GeoEngineering 1905 virtue of CO 2 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 km 2 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 ©2009 Dowlatabadi 12 Intolerable? Antigua and Barbuda Marshall Islands Bahamas Mauritius Barbados Nauru Belize Niue Cape Verde Palau Comoros Papua New Guinea Cook Islands Samoa Cuba Singapore Cyprus Seychelles Dominica Sao Tome and Principe Dominican Republic Solomon Islands Fiji St. Kitts and Nevis Federated States of Micronesia St. Lucia Grenada St. Vincent and the Grenadines Guinea-Bissau Suriname Guyana Tonga Haiti Trinidad and Tobago Jamaica Tuvalu Kiribati Vanuatu Maldives Palau Kiribati Nauru Florida Keys

13 ©2009 Dowlatabadi 13 Florida +6m Sea Level Rise

14 ©2009 Dowlatabadi 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 ©2009 Dowlatabadi 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 ©2009 Dowlatabadi 16 Blinds in Space At L1, the angle of scatter needs to be ~ 0.01 rad ~3x10 3 t mass

17 ©2009 Dowlatabadi 17 Sails in Orbit source: In earth orbit, the angle of scatter needs to be ~ 1 rad ~3x10 5 t

18 ©2009 Dowlatabadi 18 More Persistent Clouds source:

19 ©2009 Dowlatabadi 19 Modelling Results Gavindasamy & Caldeira (2000, GRL) modelled a 1.8% reduction in solar constant. –In 2xCO 2 run 97% of surface temperatures were significantly different to control. –In 2xCO 2 +Geoengineering, 15% of pixels on earth had significantly different temperature and seasonal patterns were not different to control. Budyko (1950s) –~10 7 tSO 2 in stratosphere counters 2xCO 2 forcing. –Jet travel in 2005 led to 250MtC of CO 2 emissions. If we use 2% S fuel dispersal will be free.

20 ©2009 Dowlatabadi 20 Teller et al. 10 5 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.

21 ©2009 Dowlatabadi 21 Ocean Fertilisation source:

22 ©2009 Dowlatabadi 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 cant find any of the papers or data on these any more!

23 ©2009 Dowlatabadi 23 Lock It Up Geologic weathering provides the material for normal sequestration of CO 2. CO 2 has an exothermic reaction with serpentine rocks (MgSiO 3 ). In principal, power-plants can separate CO 2 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. d_Pictures/SouthCoast/0304_Serpentine.jpg

24 ©2009 Dowlatabadi 24 Geoengineering Energy BalanceEnergy Transport Short Wave Albedo Long Wave Emissivity Ocean Atmosphere & Surface Goals space & atmospheric scatterers surface albedo uptake of CO 2 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 CH 4, O + for N 2 O large dams (Gibraltar) OTEC iceberg transport surface treatments wind turbines Cost ~50 B - ~300B to offset 2xCO 2 x10~100??

25 ©2009 Dowlatabadi 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 ©2009 Dowlatabadi 26 CO 2 Capture: Sleipner, Norway $FILE/sleipner.jpg $FILE/sleipner.jpg

27 ©2009 Dowlatabadi 27 No Black Magic in Amine Process

28 ©2009 Dowlatabadi 28 Below The Waves

29 ©2009 Dowlatabadi 29 CO 2 Injection Enhanced oil recovery using CO 2 injection has been used for 3 decades.

30 ©2009 Dowlatabadi 30 Even in Florida

31 ©2009 Dowlatabadi 31 CO 2 Reservoirs & Leaks!

32 ©2009 Dowlatabadi 32 Reservoir Sizes Geological –Depleted oil and gas reservoirs: 200-500 GtC –Deep saline aquifers: 10 2 -10 4 GtC –Deep coal beds: 100-200 GtC –Chemical reaction with Silicate rocks. Oceanic –Capacity is large: ~ 10 3 -10 4 GtC; depending on the acceptable degree of acidification. –Atmosphere-ocean carbon equilibrium: ~80% in ~300 years.

33 ©2009 Dowlatabadi 33 Renewables: Biomass Average power use in more industrial countries: –5kW/cap. Range of energy capture in terrestrial systems: –0.2 - 2 Wm 2 Area needed to meet all needs for average person: –0.5 hectare/capita = 1/2 of (croplands + forests)

34 ©2009 Dowlatabadi 34 ¢/kWh tCO 2 /Gj Electricity: GHG vs. Cost

35 ©2009 Dowlatabadi 35 Cost to Intervene Geoengineering Mitigation CSS % Climate Change Averted Cost 010050 0

36 ©2009 Dowlatabadi 36 Cost of Mitigation Option$/tCRisk Stratospheric SO 2 <<1 Atmospheric chemistry Solar Shields0.05-0.5 Does not address other impacts of CO 2 increase Ocean: Iron1-10 Is Fe really limiting?can this be a long-term solutions? Ocean: Phosphate3-10 Oxygen depletion, ecological shift, long term capture questionable Intensive forestry10-100 Biodiversity and soils. CO 2 in ground50-150 Low CO 2 in ocean50-150 Moderate uncertainty about fate

37 ©2009 Dowlatabadi 37 Policy A shot-gun marriage between: –the available AND –the imperative

38 ©2009 Dowlatabadi 38

39 ©2009 Dowlatabadi 39 Earth of tomorrow?

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