Transcript Presentation

A framework for possible
geoengineering impacts
Dr Nem Vaughan
Tyndall Centre for Climate Change Research
University of East Anglia
[email protected]
31st January 2011
www.iagp.ac.uk
Slide 2
Outline
• Geoengineering
– carbon and solar
• Impacts
– direct and indirect
– local to global
– traceable, attributable
• What we do and don’t know about the impact of
geoengineering on ecosystems
Slide 2
Outline
• Geoengineering
– carbon and solar
• Impacts
– direct and indirect
– local to global
– traceable, attributable
• What we do and don’t know about the impact of
geoengineering on ecosystems
Slide 2
Outline
• Geoengineering
– carbon and solar
• Impacts
– direct and indirect
– local to global
– traceable, attributable
• What we do and don’t know about the impact of
geoengineering on ecosystems
Slide 3
Types of geoengineering
Vaughan & Lenton (in press) Climatic Change
Slide 4
Carbon geoengineering
Carbon removal
Capture
Ocean
Land
Novel
Storage
Ocean
Land
Geology
Slide 4
Carbon geoengineering
Carbon removal
Capture
Ocean
Land
Novel
Storage
Ocean
Land
Geology
Slide 4
Carbon geoengineering
Carbon removal
Capture
Ocean
Land
Novel
Storage
Ocean
Land
Geology
Slide 5
Solar geoengineering
Reflective approaches
Space
Stratosphere
Troposphere
Surface
Land
Ocean
Slide 5
Solar geoengineering
Reflective approaches
Space
Stratosphere
Troposphere
Surface
Land
Ocean
Slide 6
Impacts of carbon geoengineering
• Addresses excess of CO2 in the atmosphere
• Slow to impact, but lasting
• Scale of intervention
• human cumulative emissions: 354 PgC
• afforestation (300PgC)
• Competition with other land use/space
• water, fertiliser, fast growing species, monoculture?
• Storage viability
• terrestrial, ocean or geology
• Very rapid removal may cause natural sinks to release carbon
Slide 6
Impacts of carbon geoengineering
• Addresses excess of CO2 in the atmosphere
• Slow to impact, but lasting
• Scale of intervention
• human cumulative emissions: 354 PgC
• afforestation (300PgC)
• Competition with other land use/space
• water, fertiliser, fast growing species, monoculture?
• Storage viability
• terrestrial, ocean or geology
• Very rapid removal may cause natural sinks to release carbon
Slide 6
Impacts of carbon geoengineering
• Addresses excess of CO2 in the atmosphere
• Slow to impact, but lasting
• Scale of intervention
• human cumulative emissions: 354 PgC
• afforestation (300PgC)
• Competition with other land use/space
• water, fertiliser, fast growing species, monoculture?
• Storage viability
• terrestrial, ocean or geology
• Very rapid removal may cause natural sinks to release carbon
Slide 6
Impacts of carbon geoengineering
• Addresses excess of CO2 in the atmosphere
• Slow to impact, but lasting
• Scale of intervention
• human cumulative emissions: 354 PgC
• afforestation (300PgC)
• Competition with other land use/space
• water, fertiliser, fast growing species, monoculture?
• Storage viability
• terrestrial, ocean or geology
• Very rapid removal may cause natural sinks to release carbon
Slide 6
Impacts of carbon geoengineering
• Addresses excess of CO2 in the atmosphere
• Slow to impact, but lasting
• Scale of intervention
• human cumulative emissions: 354 PgC
• afforestation (300PgC)
• Competition with other land use/space
• water, fertiliser, fast growing species, monoculture?
• Storage viability
• terrestrial, ocean or geology
• Very rapid removal may cause natural sinks to release carbon
Slide 7
Impacts of solar geoengineering
• potentially quick to change temperature
• addresses a symptom (not the cause)
• rate of change
– potentially quite fast (on and off)
• long term commitment?
• ocean acidification
– untreated or possible worsened
• decreased global precipitation
– evident in some modelling results
• residual warming
– i.e. still warmer in poles
Slide 7
Impacts of solar geoengineering
• potentially quick to change temperature
• addresses a symptom (not the cause)
• rate of change
– potentially quite fast (on and off)
• long term commitment?
• ocean acidification
– untreated or possible worsened
• decreased global precipitation
– evident in some modelling results
• residual warming
– i.e. still warmer in poles
Slide 7
Impacts of solar geoengineering
• potentially quick to change temperature
• addresses a symptom (not the cause)
• rate of change
– potentially quite fast (on and off)
• long term commitment?
• ocean acidification
– untreated or possible worsened
• decreased global precipitation
– evident in some modelling results
• residual warming
– i.e. still warmer in poles
Slide 7
Impacts of solar geoengineering
• potentially quick to change temperature
• addresses a symptom (not the cause)
• rate of change
– potentially quite fast (on and off)
• long term commitment?
• ocean acidification
– untreated or possible worsened
• decreased global precipitation
– evident in some modelling results
• residual warming
– i.e. still warmer in poles
Slide 7
Impacts of solar geoengineering
• potentially quick to change temperature
• addresses a symptom (not the cause)
• rate of change
– potentially quite fast (on and off)
• long term commitment?
• ocean acidification
– untreated or possible worsened
• decreased global precipitation
– evident in some modelling results
• residual warming
– i.e. still warmer in poles
Slide 7
Impacts of solar geoengineering
• potentially quick to change temperature
• addresses a symptom (not the cause)
• rate of change
– potentially quite fast (on and off)
• long term commitment?
• ocean acidification
– untreated or possible worsened
• decreased global precipitation
– evident in some modelling results
• residual warming
– i.e. still warmer in poles
Slide 8
Types of geoengineering
Carbon removal
Reflective approaches
Capture
Ocean
Storage
Space
Ocean
Land
Novel
Stratosphere
Land
Geology
Troposphere
Surface
Land
Ocean
Slide 9
Impacts of geoengineering
• Impacts
– direct or indirect
– intended or unintended
• Local, regional, global
– displaced spatially and/or temporally
• Example: marine stratocumulus albedo change
• Example: large scale afforestation
Slide 9
Impacts of geoengineering
• Impacts
– direct or indirect
– intended or unintended
• Local, regional, global
– displaced spatially and/or temporally
• Example: marine stratocumulus albedo change
• Example: large scale afforestation
Slide 9
Impacts of geoengineering
• Impacts
– direct or indirect
– intended or unintended
• Local, regional, global
– displaced spatially and/or temporally
• Example: marine stratocumulus albedo change
• Example: large scale afforestation
Slide 10
Example: Marine stratocumulus albedo change
Global
Direct
Indirect
global
cooling
Local
regional
cooling
surface water
cooling
Slide 10
Example: Marine stratocumulus albedo change
Global
Direct
global
cooling
Local
regional
cooling
surface water
cooling
water column
light attenuation
delayed
precipitation
Indirect
water column
stratification
Slide 10
Example: Marine stratocumulus albedo change
Global
Direct
global
cooling
Local
regional
cooling
surface water
cooling
water column
light attenuation
Changes to ocean
carbon sink ?
delayed
precipitation
Indirect
perturb ENSO?
water column
stratification
impact on
phytoplankton?
Slide 11
Example: Large scale afforestation
Global
global
cooling
Direct
Local
water
demand
regional albedo
change
fertiliser addition
atmospheric
chemistry - VOC
production
Indirect
fertiliser runoff
Slide 11
Example: Large scale afforestation
Global
global
cooling
Direct
Local
water
demand
regional albedo
change
fertiliser addition
atmospheric
chemistry - VOC
production
fertiliser runoff
Indirect
regional impact
on water cycle?
impact on river
systems?
Slide 12
Impacts of geoengineering
• Traceable, attributable
– spatially and/or temporally displaced
• Ability to distinguish from natural variability and/or
anthropogenic climate change?
– particularly for solar geoengineering
• Example: Atlantic sea surface temperatures
• Example: Southern Ocean
Slide 12
Impacts of geoengineering
• Traceable, attributable
– spatially and/or temporally displaced
• Ability to distinguish from natural variability and/or
anthropogenic climate change?
– particularly for solar geoengineering
• Example: Atlantic sea surface temperatures
• Example: Southern Ocean
Slide 12
Impacts of geoengineering
• Traceable, attributable
– spatially and/or temporally displaced
• Ability to distinguish from natural variability and/or
anthropogenic climate change?
– particularly for solar geoengineering
• Example: Atlantic sea surface temperatures
• Example: Southern Ocean
Slide 13
Example: Atlantic
• Modelling solar geoengineering
– (Lunt et al 2008, Latham et al 2008)
– increased Atlantic North-South gradient in sea surface temperatures
– cooling in South Atlantic relative to North Atlantic
• Atlantic N-S gradient
– controlling factor in West African Monsoon activity
– well correlated with precipitation in the Sahel (Peyrille et al 2007)
– correlated with reduction in dry season rainfall in West Amazonian (Cox et
al 2008)
• Potential impacts on Amazon or West African Monsoon
• Traceable? Attributable?
Slide 13
Example: Atlantic
• Modelling solar geoengineering
– (Lunt et al 2008, Latham et al 2008)
– increased Atlantic North-South gradient in sea surface temperatures
– cooling in South Atlantic relative to North Atlantic
• Atlantic N-S gradient
– controlling factor in West African Monsoon activity
– well correlated with precipitation in the Sahel (Peyrille et al 2007)
– correlated with reduction in dry season rainfall in West Amazonian (Cox et
al 2008)
• Potential impacts on Amazon or West African Monsoon
• Traceable? Attributable?
Slide 13
Example: Atlantic
• Modelling solar geoengineering
– (Lunt et al 2008, Latham et al 2008)
– increased Atlantic North-South gradient in sea surface temperatures
– cooling in South Atlantic relative to North Atlantic
• Atlantic N-S gradient
– controlling factor in West African Monsoon activity
– well correlated with precipitation in the Sahel (Peyrille et al 2007)
– correlated with reduction in dry season rainfall in West Amazonian (Cox et
al 2008)
• Potential impacts on Amazon or West African Monsoon
• Traceable? Attributable?
Slide 13
Example: Atlantic
• Modelling solar geoengineering
– (Lunt et al 2008, Latham et al 2008)
– increased Atlantic North-South gradient in sea surface temperatures
– cooling in South Atlantic relative to North Atlantic
• Atlantic N-S gradient
– controlling factor in West African Monsoon activity
– well correlated with precipitation in the Sahel (Peyrille et al 2007)
– correlated with reduction in dry season rainfall in West Amazonian (Cox et
al 2008)
• Potential impacts on Amazon or West African Monsoon
• Traceable? Attributable?
Slide 14
Example: Southern Ocean
• Stratospheric ozone depletion (Tilmes et al 2008)
– Stratospheric ozone depletion over Antarctica
– key driver of observed changes in the Southern Hemisphere Annular Mode
(SAM) in recent decades (Thompson & Solomon, 2002)
– which is also contributed to by greenhouse gas forcing (Perlwitz et al 2008)
• Southern Hemisphere Annular Mode (SAM)
– Observed strengthening of Southern Ocean winds has been attributed to
the shift of the SAM to a positive state (Perlwitz et al 2008)
• Reduced efficiency of Southern Ocean carbon sink
– The strengthening of these winds has been suggested to cause a reduction
in the efficiency of the Southern Ocean carbon sink (Le Quere et al 2007)
• Traceable? Attributable?
Slide 14
Example: Southern Ocean
• Stratospheric ozone depletion (Tilmes et al 2008)
– Stratospheric ozone depletion over Antarctica
– key driver of observed changes in the Southern Hemisphere Annular Mode
(SAM) in recent decades (Thompson & Solomon, 2002)
– which is also contributed to by greenhouse gas forcing (Perlwitz et al 2008)
• Southern Hemisphere Annular Mode (SAM)
– Observed strengthening of Southern Ocean winds has been attributed to
the shift of the SAM to a positive state (Perlwitz et al 2008)
• Reduced efficiency of Southern Ocean carbon sink
– The strengthening of these winds has been suggested to cause a reduction
in the efficiency of the Southern Ocean carbon sink (Le Quere et al 2007)
• Traceable? Attributable?
Slide 14
Example: Southern Ocean
• Stratospheric ozone depletion (Tilmes et al 2008)
– Stratospheric ozone depletion over Antarctica
– key driver of observed changes in the Southern Hemisphere Annular Mode
(SAM) in recent decades (Thompson & Solomon, 2002)
– which is also contributed to by greenhouse gas forcing (Perlwitz et al 2008)
• Southern Hemisphere Annular Mode (SAM)
– Observed strengthening of Southern Ocean winds has been attributed to
the shift of the SAM to a positive state (Perlwitz et al 2008)
• Reduced efficiency of Southern Ocean carbon sink
– The strengthening of these winds has been suggested to cause a reduction
in the efficiency of the Southern Ocean carbon sink (Le Quere et al 2007)
• Traceable? Attributable?
Slide 14
Example: Southern Ocean
• Stratospheric ozone depletion (Tilmes et al 2008)
– Stratospheric ozone depletion over Antarctica
– key driver of observed changes in the Southern Hemisphere Annular Mode
(SAM) in recent decades (Thompson & Solomon, 2002)
– which is also contributed to by greenhouse gas forcing (Perlwitz et al 2008)
• Southern Hemisphere Annular Mode (SAM)
– Observed strengthening of Southern Ocean winds has been attributed to
the shift of the SAM to a positive state (Perlwitz et al 2008)
• Reduced efficiency of Southern Ocean carbon sink
– The strengthening of these winds has been suggested to cause a reduction
in the efficiency of the Southern Ocean carbon sink (Le Quere et al 2007)
• Traceable? Attributable?
Slide 15
What we do (and don’t) know...
• Generally very little about ecosystem impacts due to lack of large
scale testing...
• ...just have extrapolation of natural analogues and/or modelling
work
• Ecosystem impacts
– general terms i.e. carbon or solar
• direct and indirect, scale (local to global)
– intervention specific, i.e. impacts of biochar
• direct and indirect, scale (local to global)
Slide 15
What we do (and don’t) know...
• Generally very little about ecosystem impacts due to lack of large
scale testing...
• ...just have extrapolation of natural analogues and/or modelling
work
• Ecosystem impacts
– general terms i.e. carbon or solar
• direct and indirect, scale (local to global)
– intervention specific, i.e. impacts of biochar
• direct and indirect, scale (local to global)
Slide 15
What we do (and don’t) know...
• Generally very little about ecosystem impacts due to lack of large
scale testing...
• ...just have extrapolation of natural analogues and/or modelling
work
• Ecosystem impacts
– general terms i.e. carbon or solar
• direct and indirect, scale (local to global)
– intervention specific, i.e. impacts of biochar
• direct and indirect, scale (local to global)
Slide 16
Conclusions
• Types of geoengineering
• Framework for impacts
– scale
– direct/indirect
• Limited information
on potential
ecosystem impacts
Carbon
Solar
Slide 16
Conclusions
• Types of geoengineering
Carbon
Solar
• Framework for impacts
– scale
– direct/indirect
• Limited information
on potential
ecosystem impacts
Global
Direct
Indirect
Local
Slide 16
Conclusions
• Types of geoengineering
Carbon
Solar
• Framework for impacts
– scale
– direct/indirect
• Limited information
on potential
ecosystem impacts
Global
Direct
Indirect
Local
Slide 17
Thank you
Imagery: freeimages.co.uk, NASA, Carbon Engineering Ltd
References
Vaughan & Lenton (in press) A review of climate geoengineering proposals Climatic Change
Cox et al (2008) Increasing risk of Amazonian drought due to decreasing aerosol pollution Nature 453:212
Peyrille et al (2007) An idealised two-dimensional framework to study the West African Monsoon. Part I: validation
and key controlling factors J Atmos Sci 64:2765
Lunt et al (2008) ‘Sunshade world’: a fully coupled GCM evaluation of the climatic impacts of geoengineering
Geophys Res Lett 35:L12710
Latham et al (2008) Global temperature stabilization via controlled albedo enhancement of low-level maritime
clouds Phil Trans R Soc A 366:3969
Thompson & Solomon (2002) Interpretation of recent southern hemisphere climate change. Science 296:895
Le Quere et al (2007) Saturation of the Southern Ocean CO2 sink due to recent climate change. Science 316:1735
Perlwitz et al (2008) Impact of stratospheric ozone hole recovery on Antarctic climate. Geophys Res Lett 35:L08714
Tilmes et al (2008) The sensitivity of Polar ozone depletion to proposed geoengineering schemes. Science 320:1201