Climate engineering 1

Climate engineeringSee also: environmental engineering, geotechnical engineering and planetary engineering

An oceanic phytoplankton bloom in the SouthAtlantic Ocean, off the coast of Argentina. The

aim of ocean iron fertilization in theory is toincrease such blooms by adding some iron, whichwould then draw carbon from the atmosphere and

fix it on the seabed.

Climate engineering, also referred to as geoengineering, is thedeliberate and large-scale intervention in the Earth’s climatic systemwith the aim of reducing global warming.[1] Climate engineering hastwo categories of technologies- carbon dioxide removal and solarradiation management. Carbon dioxide removal addresses a cause ofclimate change by removing one of the greenhouse gases from theatmosphere. Solar radiation management attempts to offset effects ofgreenhouse gases by causing the Earth to absorb less solar radiation.

Geoengineering has been proposed as a potential third option fortackling global warming, alongside mitigation and adaptation.Scientists do not typically suggest geoengineering the climate as analternative to emissions control, but rather an accompanying strategy.Reviews of geoengineering techniques for climate control haveemphasised that they are not substitutes for emission controls and haveidentified potentially stronger and weaker schemes. The costs, benefits,and risks of many geoengineering approaches to climate change are notwell understood.[2] However, a study from 2014 concluded that themost common climate engineering methods are either relativelyineffective or have potentially severe side effects and cannot bestopped without causing rapid climate change.

There are no known large-scale climate engineering projects except one conducted outside the scientific mainstreamby Russ George. Almost all research has consisted of computer modelling or laboratory tests, and attempts to moveto real-world experimentation have proved controversial. Some limited tree planting and cool roof projects arealready underway. Ocean iron fertilization has been given small-scale research trials. Field research into sulfuraerosols has also started.

Voices of caution against viewing geoengineered interventions as a simple solution to climate change are largely dueto the risks and partially unknown side-effects of the technologies in question. Given the vastly insufficient action onemissions reductions in climate policy to date some have argued though that the risks of such interventions are to beseen in the context of risks of dangerous climate change. As a rule of thumb it would appear that the scale of risksand costs of each climate engineering option appear to be somewhat inverse: The lower the costs, the greater therisks.WP:POV Some have suggested that the concept of geoengineering the climate presents a moral hazard becauseit could reduce political and public pressure for emissions reduction. Groups such as ETC Group and individualssuch as Raymond Pierrehumbert have called for a moratorium on deployment and out-of-doors testing ofgeoengineering techniques for climate control.[3]

Climate engineering 2

BackgroundSeveral notable organizations have investigated geoengineering with a view to evaluating its potential, including theUS Congress, NASA, the Royal Society, the Institute of Mechanical Engineers,[4] and the UK Parliament. TheAsilomar International Conference on Climate Intervention Technologies was convened to identify and develop riskreduction guidelines for climate intervention experimentation.Major environmental organisations such as Friends of the Earth and Greenpeace have typically been reluctant toendorse solar radiation management, but are often more supportive of some carbon dioxide removal projects, such asafforestation and peatland restoration. Some authors have argued that any public support for geoengineering mayweaken the fragile political consensus to reduce greenhouse gas emissions.

Proposed strategiesSee also: List of proposed geoengineering projectsSeveral geoengineering strategies have been proposed. IPCC documents detail several notable proposals. These fallinto two main categories: solar radiation management and carbon dioxide removal. However, other proposals exist.The Geoengineering Climate: Technical Evaluation and Discussion of Impacts project of the National Academy ofSciences funded by United States agencies, including NOAA, NASA, and the CIA, commenced in March 2013, isexpected to issue a report in fall 2014."An ad hoc committee will conduct a technical evaluation of a limited number of proposed geoengineeringtechniques, including examples of both solar radiation management (SRM) and carbon dioxide removal (CDR)techniques, and comment generally on the potential impacts of deploying these technologies, including possibleenvironmental, economic, and national security concerns. The study will:1.1. Evaluate what is currently known about the science of several (3-4) selected example techniques, including

potential risks and consequences (both intended and unintended), such as impacts, or lack thereof, on oceanacidification,

2.2. Describe what is known about the viability for implementation of the proposed techniques includingtechnological and cost considerations,

3.3. Briefly explain other geoengineering technologies that have been proposed (beyond the selected examples), and4.4. Identify future research needed to provide a credible scientific underpinning for future discussions.The study will also discuss historical examples of related technologies (e.g., cloud seeding and other weathermodification) for lessons that might be learned about societal reactions, examine what international agreements existwhich may be relevant to the experimental testing or deployment of geoengineering technologies, and briefly explorepotential societal and ethical considerations related to geoengineering. This study is intended to provide a careful,clear scientific foundation that informs ethical, legal, and political discussions surrounding geoengineering.The project has support from the National Academy of Sciences, the U.S. intelligence community, the NationalOceanic and Atmospheric Administration, and the National Aeronautics and Space Administration. The approximatestart date for the project is March 2013; a report is expected be issued in fall 2014."[5]

Climate engineering 3

Solar radiation managementMain article: Solar radiation managementSee also: Stratospheric sulfate aerosols (geoengineering) and Marine Cloud BrighteningSolar radiation management (SRM)[6] projects seek to reduce sunlight absorbed (ultra-violet, near infra-red andvisible). This would be achieved by deflecting sunlight away from the Earth, or by increasing the reflectivity(albedo) of the atmosphere or the Earth's surface. These methods do not reduce greenhouse gas concentrations in theatmosphere, and thus do not seek to address problems such as the ocean acidification caused by CO2. Solar radiationmanagement projects often have the advantage of speedy deployment and effect. While greenhouse gas remediationoffers a more comprehensive possible solution to climate change, it does not give instantaneous results; for that,solar radiation management is required.Wikipedia:Disputed statementSolar radiation management methods may include:• Surface-based (land or ocean albedo modification); e.g. cool roof—using pale-coloured roofing and paving

materials.• Troposphere-based, for example cloud whitening – using fine sea water spray to whiten clouds and thus increase

cloud reflectivity.• Upper atmosphere-based: creating reflective aerosols, such as stratospheric sulfate aerosols, aluminium oxide

particles, even specifically designed self-levitating aerosols.• Space-based: space sunshade—obstructing solar radiation with space-based mirrors, asteroid dust, etc.

Carbon dioxide removalMain articles: Carbon dioxide removal, Greenhouse gas remediation and Carbon sequestrationCarbon dioxide removal projects seek to remove greenhouse gases from the atmosphere. Proposed methods includethose that directly remove such gases from the atmosphere, as well as indirect methods that seek to use naturalprocesses (e.g. tree planting). Many projects overlap with carbon capture and storage and carbon sequestrationprojects, and may not be considered to be geoengineering by all commentators. Techniques in this category include:• Creating biochar and mixing it with soil to create terra preta• Bio-energy with carbon capture and storage to sequester carbon and simultaneously provide energy• Carbon air capture to remove carbon dioxide from ambient air•• Planting trees to offset carbon emissions• Ocean nourishment including iron fertilisation of the oceans

Climate engineering 4

Significant reduction in ice volume in the Arctic Ocean in the rangebetween 1979 and 2007 years

Justification

Tipping points and positive feedback

Climate change during the last 65 million years. The Paleocene–Eocene ThermalMaximum is labelled PETM.

It is argued that climate change may crosstipping points where elements of the climatesystem may 'tip' from one stable state toanother stable state, much like a glasstipping over. When the new state is reached,further warming may be caused by positivefeedback effects,. An example of a proposedcausal chain leading to runaway globalwarming is the collapse of Arctic sea icetriggering subsequent release of methane.

The precise identity of such "tipping points"is not clear, with scientists taking differingviews on whether specific systems arecapable of "tipping" and the point at whichthis "tipping" will occur. An example of a previous tipping point is that which preceded the rapid warming leadingup to the Paleocene–Eocene Thermal Maximum. Once a tipping point is crossed, cuts in anthropogenic greenhousegas emissions will not be able to reverse the change. Conservation of resources and reduction of greenhouseemissions, used in conjunction with geoengineering, are therefore considered a viable option by somecommentators.[7] Geoengineering offers the hope of temporarily reversing some aspects of climate change andallowing the natural climate to be substantially preserved whilst greenhouse gas emissions are brought under controland removed from the atmosphere by natural or artificial processes.

Climate engineering 5

CostsSome geoengineering techniques, such as cool roof techniques, can be achieved at little or no cost, and may evenoffer a financial payback. IPCC (2007) concluded that reliable cost estimates for geoengineering options had notbeen published. More recently, early research into costs of solar radiation management have been published. Thissuggests that "well designed systems" might be available for costs in the order of a few hundred million dollars peryear. These are much lower than costs to achieve comprehensive reductions in CO2 emissions.Wikipedia:Citationneeded Such costs would be within the budget of most nations, and even a handful of rich individuals.In their 2009 report Geoengineering the climate the Royal Society adjudged afforestation and stratospheric aerosolsas the methods with the "highest affordability" (meaning lowest costs). Furthermore stratospheric aerosol injection,having the highest effectiveness and affordability, would be the nearest approximation to the "ideal method", withthe (significant) disadvantage of high uncertainties considering safety and unwanted side effects. While afforestationscored highly for safety, it was found to be of limited effectiveness for treating climate change (see Table 5.1, Figure5.1., pages 48–49)

Ethics and responsibilityClimate engineering would represent a large-scale, intentional effort to modify the environment, which differ frominadvertent climate change through activities such as burning fossil fuels. Intentional climate change is viewed verydifferently from a moral standpoint.[8] This raises questions of whether we as humans have the right to change theclimate, and under what conditions this right obtains. Furthermore, ethical arguments often confront largerconsiderations of worldview, including individual and social religious commitments. For many, religious beliefs arepivotal in defining the role of human beings in the wider world. Some religious communities might claim thathumans have no responsibility in managing the climate, instead seeing such world systems as the exclusive domainof a Creator. In contrast, other religious communities might see the human role as one of "stewardship" orbenevolent management of the world.[9] The question of ethics also relates to issues of policy decision-making. Forexample, the selection of a globally agreed target temperature is a significant problem in any geoengineeringgovernance regime, as different countries or interest groups may seek different global temperatures.[10]

What most ethicists, policy-makers, and scientists agree on is this: Solar radiation management is an incompletesolution to global warming.[11] The possible option of geoengineering may reduce incentives to reduce emissions ofgreenhouse gases. It is argued that geoengineering could be used to 'buy time' before drastic climate change happens,allowing mitigation and adaptation measures more time to be implemented and work.[12] But the opposition pointsout that the resources spent on geoengineering could be used for mitigation and efforts to reduce emissions ofgreenhouse gases. Geoengineering also does not resolve other issues related to increasing levels of carbon dioxide.

Political viabilityIt has been argued that regardless of the economic, scientific and technical aspects, the difficulty of achievingconcerted political action on climate change requires other approaches. Those arguing political expediency say thedifficulty of achieving meaningful emissions cuts and the effective failure of the Kyoto Protocol demonstrate thepractical difficulties of achieving carbon dioxide emissions reduction by the agreement of the internationalcommunity. However, others point to support for geoengineering proposals among think tanks with a history ofclimate change skepticism and opposition to emissions reductions as evidence that the prospect of geoengineering isitself already politicized and being promoted as part of an argument against the need for (and viability of) emissionsreductions; that, rather than geoengineering being a solution to the difficulties of emissions reductions, the prospectof geoengineering is being used as part of an argument to stall emissions reductions in the first place.Geoenginering poses several challenges in the context of governance because of issues of power and jurisdiction.[]

Geoengineering as a climate change solution differs from other mitigation and adaptation strategies. Unlike a carbon trading system that would be focused on participation from multiple parties along with transparency, monitoring

Climate engineering 6

measures and compliance procedures; this is not necessarily required by geoengineering. Bengtsson[13] (2006)argues that "the artificial release of sulphate aerosols is a commitment of at least several hundred years". Thishighlights the importance for a political framework that is sustainable enough to contain a multilateral commitmentover such a long period and yet is flexible as the techniques innovate through time. There are many controversiessurrounding this topic and hence, geoengineering has been made into a very political issue. Most discussions anddebates are not about which geoengineering technique is better than the other, or which one is more economicallyand socially feasible. Discussions are broadly on who will have control over the deployment of geoengineering andunder what governance regime the deployment can be monitored and supervised. This is especially important due tothe regional variability of the effects of many geoengineering techniques, benefiting some countries while damagingothers. The challenge posed by geoengineering is not how to get countries to do it. It is to address the fundamentalquestion of who should decide whether and how geoengineering should be attempted – a problem of governance.[14]

Risks and criticisms

Change in sea surface pH caused by anthropogenic CO2 between the 1700s and the1990s. This ocean acidification will still be a major problem unless atmospheric

CO2 is reduced.

Various criticisms have been made ofgeoengineering, particularly Solar RadiatonManagement (SRM) methods. Decisionmaking suffers from intransitivity of policychoice. Some commentators appearfundamentally opposed. Groups such asETC Group and individuals such asRaymond Pierrehumbert have called for amoratorium on geoengineering techniques.

Ineffectiveness

The effectiveness of the schemes proposedmay fall short of predictions. In ocean ironfertilization, for example, the amount ofcarbon dioxide removed from theatmosphere may be much lower thanpredicted, as carbon taken up by plankton may be released back into the atmosphere from dead plankton, rather thanbeing carried to the bottom of the sea and sequestered.[15]

Incomplete solution to CO2 emissions

Techniques that do not remove greenhouse gases from the atmosphere may control global warming, but do notreduce other effects from these gases, such as ocean acidification.[16] While not an argument against geoengineeringper se, this is an argument against reliance on geoengineering to the exclusion of greenhouse gas reduction.

Climate engineering 7

Control and predictability problemsThe full effects of various geoengineering schemes are not well understood. Matthews et al. comparedgeoengineering to a number of previous environmental interventions and concluded that "Given our current level ofunderstanding of the climate system, it is likely that the result of at least some geoengineering efforts would followprevious ecological examples where increased human intervention has led to an overall increase in negativeenvironmental consequences."Performance of the systems may become ineffective, unpredictable or unstable as a result of external events, such asvolcanic eruptions, phytoplankton blooms, El Niño, solar flares, etc., potentially leading to profound andunpredictable disruption to the climate system.It may be difficult to predict the effectiveness of projects,[17] with models of techniques giving widely varyingresults.[18] In the instances of systems which involve tipping points, this may result in irreversible effects. Climatemodelling is far from an exact science even when applied to comparatively well-understood natural climate systems,and it is made more complex by the need to understand novel and unnatural processes which by definition lackrelevant observation data.

Side effectsThe techniques themselves may cause significant foreseen or unforeseen harm. For example, the use of reflectiveballoons may result in significant litter, which may be harmful to wildlife.Ozone depletion is a risk of some geoengineering techniques, notably those involving sulfur delivery into thestratosphere.[19]

The active nature of geoengineering may in some cases create a clear division between winners and losers. Most ofthe proposed interventions are regional, such as albedo modification in the Arctic.There may be unintended climatic consequences, such as changes to the hydrological cycle including droughts[20] orfloods, caused by the geoengineering techniques, but possibly not predicted by the models used to plan them.[21]

Such effects may be cumulative or chaotic in nature, making prediction and control very difficult.Not all side effects are negative, and an increase in agricultural productivity has been predicted by some studies.

Unreliable systemsThe performance of the interventions may be inconsistent due to mechanical failure, non-availability of consumablesor funding problems.The geoengineering techniques would, in many instances, be vulnerable to being switched off or deliberatelydestroyed. As examples, cloud making ships could be switched off or sunk and space mirrors could be tilted to makethem useless. Anyone capable of exerting such power may seek to abuse it for commercial gain, military advantageor simple terrorism.

Climate engineering 8

Termination shockIf solar radiation management were to abruptly stop, the climate would rapidly warm. This would cause a suddenrise in global temperatures towards levels which would have existed without the use of the geoengineeringtechnique. The rapid rise in temperature may lead to more severe consequences than a gradual rise of the samemagnitude.

WeaponisationIn 1976, 85 countries signed the U.N. Convention on the Prohibition of Military or Any Other Hostile Use ofEnvironmental Modification Techniques. The Environmental Modification Convention generally prohibitsweaponising geoengineering techniques. However, this does not eliminate the risk. Geoengineering techniques mayserve as weapons of mass destruction, creating droughts or famines designed to destroy or disable an enemy. Theycould also be used simply to make battlefield conditions more favourable to one side or the other in a war. Forexample, laser-guided weapons are confounded by clouds, and thus switching off cloud machines would favourforces using such weapons, and switching them on would favour ground forces defending against them.Whilst laws or treaties may prevent the manipulation of the climate as a weapon of war,[22] it could be argued thatgeoengineering is itself a manipulation, and thus destroying or disabling the geoengineering structures is notprohibited. A new legal framework may be necessary in the event that large-scale geoengineering becomesestablished.Wikipedia:No original researchCarnegie's Ken Caldeira said, "It will make it harder to achieve broad consensus on developing and governing thesetechnologies if there is suspicion that gaining military advantage is an underlying motivation for its development..."

Effect on sunlight, sky and cloudsManaging solar radiation using aerosols or cloud cover would change the ratio between direct and indirect solarradiation. This may affect plant life[23] and solar energy.[24] There will be a significant effect on the appearance ofthe sky from aerosol projects, notably a hazing of blue skies and a change in the appearance of sunsets.[25] Aerosolsmay affect the formation of clouds, especially cirrus clouds.[26]

Moral hazardThe existence of such techniques may reduce the political and social impetus to reduce carbon emissions.[27]

However, this issue has been researched in an in-depth study by Ipsos MORI for NERC,[28] which does not supportthe Moral Hazard argument. Other modelling work suggests that the threat of geoengineering by a rogue state may infact increase the likelihood of emissions reduction. The issue of moral hazard means that many environmentalgroups and campaigners are reluctant to advocate geoengineering for fear of reducing the imperative to cutgreenhouse gas emissions.Other criticism comes from those who see geoengineering projects as reacting to the symptoms of global warmingrather than addressing the real causes of climate change. Because geoengineering is a form of controlling the risksassociated with global warming, it leads to a moral hazard problem. The problem is that knowledge thatgeoengineering is possible could lead to climate impacts seeming less fearsome, which could in turn lead to an evenweaker commitment to reducing greenhouse gas emissions.

Climate engineering 9

GovernanceGeoengineering opens up various political and economic issues. David Keith argues that the cost of geoengineeringthe Earth is within the realm of small countries, large corporations, or even very wealthy individuals. Steve Rayneragrees that not all geoengineering possibilities are expensive, and that some, such as ocean iron fertilisation, arewithin the reach of very wealthy individuals, calling them a "Greenfinger" (after the fictional Goldfinger). DavidVictor suggests that geoengineering is within the reach of any individual who has a small fraction of the bankaccount of Bill Gates, who takes it upon him or her self to be the "self-appointed protector of the planet". However, ithas been argued that a rogue state threatening geoengineering may strengthen action on mitigation.This may seem to eliminates any control over who gets to decide when to cool the Earth and how this should bedone. The resulting power would be enormous, and could not necessarily be readily controlled by legal, political orregulatory systems. The legal and regulatory systems may face a significant challenge in effectively regulating theuse of these technologies in a manner that allows for an acceptable result for society. There are however significantincentives for states to cooperate in choosing a specific geoengineering policy, which make unilateral deployment arather unlikely event.A small number carbon offsetting firms have in the past attempted to set up unregulated and unsupervisedgeoengineering projects. In the long-run such firms may aim to sell carbon credits to individuals, firms or countries.Geoengineering has the potential to cause significant environmental damage, and could even end up releasing furthergreenhouse gases into the atmosphere.[29] Opposition to some early schemes has been intense, with respectedenvironmental groups campaigning against them.[30] Some researchers have suggested that building a globalagreement on geoengineering deployment will be very difficult, and instead power blocs are likely to emerge.There is presently a lack of a universally agreed framework for the regulation of either geoengineering activity orresearch. The London Convention addresses some aspects of the law in relation to biomass ocean storage and oceanfertilization. Scientists at the Oxford Martin School at Oxford University have proposed a set of voluntary principles,which may guide geoengineering research. The short version of the 'Oxford Principles' is:• Principle 1: Geoengineering to be regulated as a public good.•• Principle 2: Public participation in geoengineering decision-making• Principle 3: Disclosure of geoengineering research and open publication of results•• Principle 4: Independent assessment of impacts•• Principle 5: Governance before deploymentThese principles have been endorsed by the House of Commons of the United Kingdom Science and TechnologySelect Committee on “The Regulation of Geoengineering”,[31] and have been referred to by authors discussing theissue of governance.[32]

The Asilomar conference was replicated to deal with the issue of geoengineering governance, and covered in a TVdocumentary, broadcast in Canada.

Implementation issuesThere is no general consensus that geoengineering is safe, appropriate or effective, for the reasons listed above.Other environmentalists see calls for geoengineering as part of an explicit strategy to delay emissions reductions onthe part of those with connections to coal and oil industries.[33]Wikipedia:No original research#Synthesis ofpublished material that advances a positionAll proposed geoengineering techniques require implementation on a relatively large scale, in order to make asignificant difference to the Earth's climate. The least costly schemes are budgeted at a cost of millions,[34] withmany more complex schemes such as space sunshade costing far more.

Climate engineering 10

Many techniques, again such as space sunshade, require a complex technical development process before they areready to be implemented. There is no clear institutional mechanism for handling this research and developmentprocess. As a result, many promising techniques do not have the engineering development or experimental evidenceto determine their feasibility or efficacy at present.Once a technique has been developed and tested, its implementation is still likely to be difficult. Climate change isby nature a global problem, and therefore no one institution, company or government is responsible for it. Thesubstantial costs of most geoengineering techniques therefore cannot currently be apportioned. Roll-out of suchtechnologies is therefore likely to be delayed until these issues can be resolved. A notable exception is the use ofsmall albedo manipulation projects, known as cool roof, in which the colour of roofing or paving surfaces can bemanipulated to reflect solar radiation back into space. These can be, and are, implemented by individuals, companiesand governments without controversy.[35]

Due to the radical changes caused by geoengineering interventions, legal issues are also an impediment toimplementation. The changes resulting from geoengineering necessarily benefit some people and disadvantageothers. There may therefore be legal challenges to the implementation of geoengineering techniques by thoseadversely affected by them.[36]

Evaluation of geoengineeringMost of what is known about the suggested techniques is based on laboratory experiments, observations of naturalphenomena and on computer modelling techniques. Some geoengineering schemes employ methods that haveanalogues in natural phenomena such as stratospheric sulfur aerosols and cloud condensation nuclei. As such, studiesabout the efficacy of these schemes can draw on information already available from other research, such as thatfollowing the 1991 eruption of Mount Pinatubo. However, comparative evaluation of the relative merits of eachtechnology is complicated, especially given modelling uncertainties and the early stage of engineering developmentof many geoengineering schemes.[37]

Reports into geoengineering have also been published in the United Kingdom by the Institution of MechanicalEngineers and the Royal Society. The IMechE report examined a small subset of proposed schemes (air capture,urban albedo and algal-based CO2 capture schemes), and its main conclusions were that geoengineering should be researched and trialled at the smallscale alongside a wider decarbonisation of the economy.The Royal Society review examined a wide range of geoengineering schemes and evaluated them in terms ofeffectiveness, affordability, timeliness and safety (assigning qualitative estimates in each assessment). Similarly toLenton and Vaughan, the report divided schemes into "carbon dioxide removal" (CDR) and "solar radiationmanagement" (SRM) approaches that respectively address longwave and shortwave radiation. The keyrecommendations of the report were that "Parties to the UNFCCC should make increased efforts towards mitigatingand adapting to climate change, and in particular to agreeing to global emissions reductions", and that "[nothing]now known about geoengineering options gives any reason to diminish these efforts". Nonetheless, the report alsorecommended that "research and development of geoengineering options should be undertaken to investigatewhether low risk methods can be made available if it becomes necessary to reduce the rate of warming this century".In a 2009 review study, Lenton and Vaughan evaluated a range of geoengineering schemes from those that sequester CO 2 from the atmosphere and decrease longwave radiation trapping, to those that decrease the Earth's receipt of shortwave radiation. In order to permit a comparison of disparate techniques, they used a common evaluation for each scheme based on its effect on net radiative forcing. As such, the review examined the scientific plausibility of schemes rather than the practical considerations such as engineering feasibility or economic cost. Lenton and Vaughan found that "[air] capture and storage shows the greatest potential, combined with afforestation, reforestation and bio-char production", and noted that "other suggestions that have received considerable media

Climate engineering 11

attention, in particular "ocean pipes" appear to be ineffective". They concluded that "[climate] geoengineering is bestconsidered as a potential complement to the mitigation of CO 2 emissions, rather than as an alternative to it".In October 2011, a Bipartisan Policy Center panel issued a report urging immediate researching and testing in case"the climate system reaches a 'tipping point' and swift remedial action is required".[38] The National Academy ofSciences is running 21-month project which will study how humans might influence weather patterns, assess dangersand investigate possible national security implications of geoengineering attempts. The project will be funded by theCIA, the National Oceanic and Atmospheric Administration, and NASA.

Intergovernmental Panel on Climate ChangeThe Intergovernmental Panel on Climate Change (IPCC) has assessed the scientific literature on climate engineering(referred to as "geoengineering" in its reports). The IPCC's Fourth Assessment Report was published in 2007. Itstates:

Geo-engineering options, such as ocean fertilization to remove CO2 directly from the atmosphere, orblocking sunlight by bringing material into the upper atmosphere, remain largely speculative andunproven, and with the risk of unknown side-effects. Reliable cost estimates for these options have notbeen published

Working Group I's contribution to the IPCC's Fifth Assessment Report was published in 2013. It states:[39]

Models suggest that if SRM methods were realizable they would be effective in countering increasingtemperatures, and would be less, but still, effective in countering some other climate changes. SRMwould not counter all effects of climate change, and all proposed geoengineering methods also carryrisks and side effects. Additional consequences cannot yet be anticipated as the level of scientificunderstanding about both SRM and CDR is low. There are also many (political, ethical, and practical)issues involving geoengineering that are beyond the scope of this report.

References[1] Policy Implications of Greenhouse Warming: Mitigation, Adaptation, and the Science Base (http:/ / books. nap. edu/ openbook.

php?record_id=1605& page=433) (1992), Committee on Science, Engineering, and Public Policy (COSEPUP)[2][2] , p.53.[3] Can we engineer a cooler earth? (http:/ / features. csmonitor. com/ environment/ 2008/ 07/ 16/ can-we-engineer-a-cooler-earth/ )[4] http:/ / www. imeche. org/ Libraries/ Key_Themes/ IMechEGeoengineeringReport. sflb. ashx[5][5] The extended quote is in the public domain as the work of an employee of the United States government in the performance of their duties.[6] Proposed Outline for Solar Radiation Management (Geoengineering) Framework (http:/ / thehardlook. typepad. com/ thehardlook/ files/

schnare_supplemental_testimony_a_framework_for_geoengineering. pdf)[7] http:/ / ipsnews. net/ news. asp?idnews=42662[8] Bodansky, D. (1996) May we engineer the climate? Climatic Change 33: 309–321[9] Clingerman, F. (2012) "Between Babel and Pelagius: Religion, Theology and Geoengineering," in Preston, C. (ed.), Engineering the Climate:

The Ethics of Solar Radiation Management. Lantham, MD: Lexington, pp. 201-219.[10] Victor, D. G., M. G. Morgan, J. Apt, J. Steinbruner, K. Ricke (2009) The Geoengineering Option: A last resort against global warming?

Foreign Affairs March/April 2009[11] Michaelson, J. (1998) 'Geoengineering: a climate change Manhattan project'. Stanford Environmental Law Journal, Stanford CA, January

1998[12] Gardiner, S. M. Is "Arming the Future" with geoengineering really the lesser evil? Some doubts about the ethics of intentionally

manipulating the climate system in Gardiner, S., S. Caney, D. Jamieson & H. Shue (eds) Climate Ethics: Essential Readings. OxfordUniversity Press, 2010, 284–314

[13] Bengtsson, L. (2006) 'Geo-engineering to confine climate change: is it at all feasible?' Climatic Change 77: 229–234[14][14] Barrett, S (2007) Why cooperate? The incentive to supply global public goods. Oxford University Press, Oxford[15] Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the

global ocean", Journal of Geophysical Research, vol. 112, C10011,[16] http:/ / infohost. nmt. edu/ ~chem/ wingenter/ Wingenter_PeECE_III_GRL_2007. pdf

Climate engineering 12

[17] Keith Bower et al., 2006 Computational assessment of a proposed technique for global warming mitigation via albedo-enhancement ofmarine stratocumulus clouds. Atmos. Res., vol. 82, no. 1-2, 2006, pp. 328–336

[18] http:/ / royalsociety. org/ page. asp?tip=1& id=6232[19] The Sensitivity of Polar Ozone Depletion to Proposed Geoengineering Schemes", Science, vol. 320, no. 5880, 30 May 2008, pp. 1201–1204,[20] I. M. Held et al., "Simulation of Sahel drought in the 20th and 21st centuries", Proceedings of the National Academy of Sciences, vol. 102,

no. 50, pp. 17891–17896, . Available online at: http:/ / climate. envsci. rutgers. edu/ pdf/ 2008JD010050small. pdf[21] Keith Bower et al., 2006 Computational assessment of a proposed technique for global warming mitigation via albedo-enhancement of

marine stratocumulus clouds. Atmos. Res., vol. 82, no. 1-2, 2006, pp. 328–336[22] http:/ / www. state. gov/ t/ ac/ trt/ 4783. htm[23] L. Gu et al., "Responses of Net Ecosystem Exchanges of Carbon Dioxide to Changes in Cloudiness: Results from Two North American

Deciduous Forests", Journal of Geophysical Research, vol. 104, no. 31, pp. 421–31, 434 (1999); L. Gu et al., "Advantages of DiffuseRadiation for Terrestrial Ecosystem Productivity", Journal of Geophysical Research, vol. 107, (2002); L. Gu et al., "Response of a DeciduousForest to the Mount Pinatubo Eruption: Enhanced Photosynthesis", Science, vol. 299, pp. 2,035–38 (2003)

[24] Balan Govindasamy and Ken Caldeira, "Geoengineering Earth's Radiation Balance to Mitigate CO2-Induced Climate Change", GeophysicalResearch Letters, vol. 27, pp. 2,141–44 (2000). For the response of solar power systems, see Michael C. MacCracken, "Geoengineering:Worthy of Cautious Evaluation?" Climatic Change, vol. 77, pp. 235–43 (2006)

[25] NASA - Geoengineering: Why or Why Not? (http:/ / www. nasa. gov/ centers/ langley/ news/ researchernews/ rn_robockfeature. html)[26] K. Sassen et al., ";The 5–6 December 1991 FIRE IFO II Jet Stream Cirrus Case Study: Possible Influences of Volcanic Aerosols", Journal of

the Atmospheric Sciences, vol. 52, pp. 97–123 (1993)[27] David Adam, "Extreme and risky action the only way to tackle global warming, say scientists", Guardian, 1 September 2008. Available

online at: http:/ / www. guardian. co. uk/ environment/ 2008/sep/01/climatechange.scienceofclimatechange2[28] Ipsos MORI (for NERC) (2010) Experiment Earth? Report on a Public Dialogue on Geoengineering http:/ / www. nerc. ac. uk/ about/

consult/ geoengineering-dialogue-final-report. pdf[29] Urea 'climate solution' may backfire › Analysis (ABC Science) (http:/ / www. abc. net. au/ science/ articles/ 2007/ 11/ 09/ 2085584. htm)[30] News & Press | WWF (http:/ / www. worldwildlife. org/ who/ media/ press/ 2007/ WWFPresitem973. html)[31] http:/ / www. geoengineering. ox. ac. uk/ oxford-principles/ history/[32] We all want to change the world (http:/ / www. economist. com/ node/ 15814427)[33] Worldchanging | Evaluation + Tools + Best Practices: Don't Wait for the Lifeboat: A Response to Geoengineering (http:/ / www.

worldchanging. com/ archives/ / 009753. html)[34] http:/ / docs. google. com/ gview?attid=0. 1& thid=11e473ed2477ae05& a=v& pli=1[35] Cool Roofs (http:/ / www. consumerenergycenter. org/ coolroof/ )[36] The Politics of Geoengineering (http:/ / ieet. org/ index. php/ IEET/ more/ 2094/ )[37] http:/ / www. imeche. org/ media/ Public+ Affairs/ geoenginq. htm[38] Group Urges Research Into Aggressive Efforts to Fight Climate Change (http:/ / www. nytimes. com/ 2011/ 10/ 04/ science/ earth/

04climate. html), October 4, 2011[39] FAQ 7.3 (http:/ / www. climatechange2013. org/ images/ report/ WG1AR5_Chapter07_FINAL. pdf), in

• IPCC AR5 WG1 (2013), Stocker, T.F., et al., ed., Climate Change 2013: The Physical Science Basis. WorkingGroup 1 (WG1) Contribution to the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report(AR5) (http:/ / www. ipcc. ch/ report/ ar5/ wg1/ ), Cambridge University Press. Climate Change 2013 WorkingGroup 1 website. (http:/ / www. climatechange2013. org/ )

Further reading• Macnaghten, Phil; Owen, Richard (November 2011). "Environmental Science: Good Governance for

Geoengineering". Nature 479 (7373): 293. Bibcode: 2011Natur.479..293M (http:/ / adsabs. harvard. edu/ abs/2011Natur. 479. . 293M). doi: 10.1038/479293a (http:/ / dx. doi. org/ 10. 1038/ 479293a). PMID  22094673(http:/ / www. ncbi. nlm. nih. gov/ pubmed/ 22094673). – Abstract only (subscription required)

• Royal Society (September 2009) (PDF). Geoengineering the Climate: Science, Governance and Uncertainty(http:/ / royalsociety. org/ uploadedFiles/ Royal_Society_Content/ policy/ publications/ 2009/ 8693. pdf) (Report).p. 1. ISBN 978-0-85403-773-5. Retrieved 2011-12-01.

• GAO (July 2011) (PDF). Climate Engineering: Technical Status, Future Directions, and Potential Responses(http:/ / psych. cf. ac. uk/ understandingrisk/ docs/ spice. pdf) (Report). Center for Science, Technology, andEngineering. Retrieved 2011-12-01.

• Launder, Brian; Thompson, J. Michael T., eds. (December 2009). Geo-Engineering Climate Change:Environmental Necessity or Pandora's Box?. Cambridge University Press. ISBN 978-0-521-19803-5.

Climate engineering 13

• Eli Kintisch (2010). Hack the Planet: Science's Best Hope, or Worst Nightmare, for Averting ClimateCatastrophe. ISBN 978-0-470-52426-8.

• Jeff Goodell (2010). How to Cool the Planet: Geoengineering and the Audacious Quest to Fix Earth's Climate.ISBN 978-0-618-99061-0.

• Morton, Oliver (May 10, 2007). "Climate change: Is this what it takes to save the world?". Nature 447 (7141):132–136. Bibcode: 2007Natur.447..132M (http:/ / adsabs. harvard. edu/ abs/ 2007Natur. 447. . 132M). doi:10.1038/447132a (http:/ / dx. doi. org/ 10. 1038/ 447132a). PMID  17495899 (http:/ / www. ncbi. nlm. nih. gov/pubmed/ 17495899). – Abstract only (subscription required)

• James Rodger Fleming (September 15, 2010). Fixing the Sky: The Checkered History of Weather and ClimateControl. Columbia University Press. ISBN 978-0-231-14412-4.

• Granger Morgan (http:/ / www. irgc. org/ -Granger-Morgan-. html), Katharine Ricke (2010). An Opinion Piecefor IRGC (http:/ / www. irgc. org). Cooling the Earth Through Solar Radiation Management: The need forresearch and an approach to its governance. ISBN 978-2-9700672-8-3

• If Cutting Carbon Emissions Isn't Working, What's Next? (http:/ / green. blogs. nytimes. com/ 2012/ 03/ 12/if-cutting-carbon-emissions-isnt-working-whats-next) March 2012 "Suck It Up" book review

External links

Studies• Royal Society "Geoengineering the Climate: Science, Governance and Uncertainty." (http:/ / royalsociety. org/

uploadedFiles/ Royal_Society_Content/ policy/ publications/ 2009/ 8693. pdf) Report. ISBN 978-0-85403-773-5.September, 2009

• Climate Engineering (http:/ / www. climate-engineering. eu/ ) Kiel Earth Institute and Marsilius Kolleg ofHeidelberg University, since Sept 2011

• Engineering the Climate : Research Needs and Strategies for International Coordination October 2010 report(http:/ / www. washingtonpost. com/ wp-srv/ nation/ pdfs/ Geongineeringreport. pdf) from the U.S. House ofRepresentatives

• Cost evaluation study of 6 geoengineering schemes (http:/ / www. kurzweilai. net/blocking-the-sun-study-looks-at-costs-of-6-geoengineering-schemes?utm_source=KurzweilAI+ Daily+Newsletter& utm_campaign=01ee9bd702-UA-946742-1& utm_medium=email)Wikipedia:Identifying reliablesources

Articles (newspapers and magazines)• Geoengineering may be our best chance to save what sea ice is left (http:/ / www. scientificamerican. com/

article. cfm?id=geoengineering-last-chance-save-sea-ice) by Peter Wadhams Scientific American December 15,2012

• Geo-engineering - A Tool in the Fight to Tackle Climate Change, or a Dangerous Distraction? (http:/ / www.huffingtonpost. co. uk/ jon-taylor/ geoengineering-climate-change_b_1873231. html) by Jon Taylor, ClimateChange Programme Manager at WWF-UK, September 11, 2012 Huffington Post

• Field test stashes climate-warming carbon in deep ocean; Strategically dumping metal puts greenhouse gasaway, possibly for good (http:/ / www. sciencenews. org/ view/ generic/ id/ 342377/ title/Field_test_stashes_climate-warming_carbon_in_deep_ocean) July 18, 2012 Science News

• Geoengineering: An Interim strategy to curb global warming? (http:/ / www. vagabondjourney. com/geoengineering-interim-strategy-curb-global-warming-john-latham/ ) - An interview with John Latham

• What the UN ban on geoengineering really means (http:/ / www. newscientist. com/ article/dn19660-what-the-un-ban-on-geoengineering-really-means. html) November 1, 2010 by Fred Pearce of NewScientist

Climate engineering 14

• Geoengineering sparks international ban, first-ever congressional report (http:/ / www. washingtonpost. com/wp-dyn/ content/ article/ 2010/ 10/ 29/ AR2010102906361. html) Juliet Eilperin Washington Post October 30,2010

• Threat of global warming sparks U.S. interest in geoengineering (http:/ / www. washingtonpost. com/ wp-dyn/content/ article/ 2010/ 10/ 03/ AR2010100303437. html) by Juliet Eilperin of the Washington Post October 3,2010

• The powerful coalition that wants to engineer the world's climate: Businessmen, scientists and right-wingthinktanks are joining forces to promote 'geo-engineering' ideas to cool the planet's climate (http:/ / www.guardian. co. uk/ environment/ 2010/ sep/ 13/ geoengineering-coalition-world-climate) Clive Hamilton TheGuardian, September 13, 2010

• Bill Gates' cloud-whitening trials 'a dangerous experiment' (http:/ / www. guardian. co. uk/ environment/ 2010/may/ 14/ bill-gates-cloud-whitening-dangerous), The Guardian, May 14, 2010 regarding Bill Gates

• We need birth control, not geoengineering (http:/ / www. guardian. co. uk/ environment/ 2010/ apr/ 06/geoengineering-carbon-emissions), The Guardian, April 6, 2010

• "The Geoengineering Gambit" (http:/ / www. technologyreview. com/ energy/ 24157/ ), Technology Review, Jan.2010

• Re-Engineering the Earth (http:/ / www. theatlantic. com/ magazine/ archive/ 2009/ 07/ re-engineering-the-earth/7552/ ) July 2009 The Atlantic

• Geo-engineering in the Southern Ocean (http:/ / orgprints. org/ 15528/ 01/ 15528. pdf), by John Paull, AustralianNational University, 2009

• 10 Ideas That Are Changing The World: 6.Geoengineering (http:/ / www. time. com/ time/ specials/ 2007/ article/0,28804,1720049_1720050_1721653,00. html) Time (magazine), March 2008

• Geoengineering Retrospective (http:/ / www. worldchanging. com/ archives/ 008364. html) Overview of articleson geoengineering by Julia Levitt, Worldchanging, August 2008

• "Futuristic fleet of 'cloudseeders'" (http:/ / news. bbc. co. uk/ 2/ hi/ programmes/ 6354759. stm) John LathamBBC News. Feb. 15, 2007

• Geo-engineering website, describing current methods/proposals done to revert climate change by geo-engineering(http:/ / geo-engineering. blogspot. com/ ), by Sam Carana

• Climate Engineering Is Doable, as Long as We Never Stop (http:/ / www. wired. com/ science/ planetearth/ news/2007/ 07/ geoengineering) Wired (magazine), July 2007

• Geoengineering links (http:/ / www. geocrisis. com/ cpe_geoengineering_menu. htm), GeoCrisis annotated list,2006?

• Terraforming Earth IV: The Question of Methane (http:/ / www. openthefuture. com/ wcarchive/ 2005/ 08/terraforming_earth_iv_the_ques. html) August 11, 2005 Jamais Cascio

• Geoengineering: 'A Bad Idea Whose Time Has Come' (http:/ / www. npr. org/ templates/ story/ story.php?storyId=127245606) discussion on NPR

• "Geoengineering: A Climate Change Manhattan Project" (http:/ / www. metatronics. net/ lit/ geo2. html) by JayMichaelson, Stanford Environmental Law Journal, 1998

Climate engineering 15

Videos (documentaries, interviews, video reports)• A Debate on Geoengineering: Vandana Shiva vs. Gwynne Dyer (http:/ / www. democracynow. org/ 2010/ 7/ 8/

a_debate_on_geoengineering_vandana_shiva) – video report by Democracy Now!• 5 ways to save the earth (http:/ / news. bbc. co. uk/ 1/ hi/ programmes/ 6298507. stm), BBC documentary about

geo-engineering, 20 February 2007• Wonderfest 2010: Dare We Try to Engineer Earth's Climate? (http:/ / fora. tv/ 2010/ 11/ 07/

Wonderfest_2010_Dare_We_Try_to_Engineer_Earths_Climate), Speakers: Julio Friedmann, Jane C.S. Long,Location: Stanley Hall, Berkeley (CA), 11 July 2010

• Project Earth (TV series) on climate engineering

Article Sources and Contributors 16

Article Sources and ContributorsClimate engineering  Source: http://en.wikipedia.org/w/index.php?oldid=611219232  Contributors: 5 albert square, AdventurousSquirrel, Alan Liefting, Alikaalex, Altenmann, Andrewjlockley,Apotheon, Arthur Rubin, Atama, Atomicgurl00, Autonova, Awickert, BDD, Beagel, Bebe35, Belfrey, Bender235, Bgwhite, Bhadani, Bhny, BlueSky2012, Borgx, Boris Barowski, BrianEverlasting, Bryan Derksen, Capitalismojo, Carwil, Chris the speller, ChrisGualtieri, Chuck Marean, ClionarchZRaleigh, CorineDe, Cupco, Cybercobra, DASonnenfeld, Daniel J. Leivick,Daniele Pugliesi, Dmitriy01, Docu, DonutGuy, Elonka, Enescot, Erik Kennedy, Farmjustice2010, FirstPrinciples, Flumstead, FrancisTyers, Fred Bauder, Freethinker22, Gaianauta, Gasetus,Gioto, Gob Lofa, GoingBatty, GorillaWarfare, Gralo, Grantstanleywilson, Grifter1405, Ground Zero, HJ Mitchell, Icairns, Invest in knowledge, IstvanWolf, JaGa, Jackpickard1985, Jakec,JamesBWatson, Jestus47, Jim1138, John Nissen, Johnfos, JorisvS, Joshuahorton533, Jpe77, JuanFox, KimDabelsteinPetersen, KuduIO, Kwhilden, LOL, Lfstevens, Lickandqui, LilHelpa,LinguisticEngineer, Lizia7, Lorast, MC MasterChef, MINITEK, Malik Shabazz, Maranium, Martarius, Materialscientist, Mild Bill Hiccup, Motoko18, MrOllie, Mrfebruary, Nathan Johnson,Nczempin, Nealmcb, Neilrieck, Nepomuk 3, Neum, NewsAndEventsGuy, Niceguyedc, Nigelj, Nopetro, Northamerica1000, Oangola, Observer2050, Oceanflynn, Palamabron, Paul A, Pcirrus2,Pearle, Pete.irvine, Peterdx, Pinethicket, Plumbago, Poco a poco, Polargeo, Prakash021, Prokaryotes, RA0808, Redthoreau, Rhall28, Rich Farmbrough, Rjwilmsi, Roadcreature, Rotblats09,SchreyP, Scott Illini, Shining.Star, Short Brigade Harvester Boris, Skizzik, Smallman12q, Solace098, Sphilbrick, Squiddy, Srich32977, Ssilvers, TeH nOmInAtOr, Thatguyflint, Theo Pardilla,ThomasNichols, Tillman, Tiltnes, Uncle G, Viriditas, Vsmith, WVhybrid, Wavelength, Wetman, WikHead, Will Beback, William M. Connolley, Winterst, Woohookitty, Xzarnum, Yellowjade,Yngvadottir, 406 anonymous edits

Image Sources, Licenses and ContributorsFile:Phytoplankton SoAtlantic 20060215.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Phytoplankton_SoAtlantic_20060215.jpg  License: Public Domain  Contributors: NASAFile:2007 Arctic Sea Ice.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:2007_Arctic_Sea_Ice.jpg  License: Public Domain  Contributors: NASA image created by Jesse Allen, usingAMSR-E data courtesy of the National Snow and Ice Data (NSIDC), and sea ice extent contours courtesy of Terry Haran and Matt Savoie, NSIDC, based on Special Sensor Microwave Imager(SSM/I) data.File:65 Myr Climate Change.png  Source: http://en.wikipedia.org/w/index.php?title=File:65_Myr_Climate_Change.png  License: unknown  Contributors: Bender235, Boronian, Ciaurlec,Dragons flight, Glenn, Kevmin, Martinlsmith, Moroboshi, Pflatau, Saperaud, SeL media, 9 anonymous editsFile:WOA05 GLODAP del pH AYool.png  Source: http://en.wikipedia.org/w/index.php?title=File:WOA05_GLODAP_del_pH_AYool.png  License: Creative Commons Attribution-Sharealike3.0  Contributors: Plumbago

LicenseCreative Commons Attribution-Share Alike 3.0//creativecommons.org/licenses/by-sa/3.0/