The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol Injection
Abstract The specifics of the simulated injection choices in the case of stratospheric aerosol injections (SAI) are part of the crucial context necessary for meaningfully discussing the impacts that a deployment of SAI would have on the planet. One of the main choices is the desired amount of coolin...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2023-08-01
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| Series: | Earth's Future |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2023EF003851 |
| _version_ | 1797733433894502400 |
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| author | D. Visioni E. M. Bednarz D. G. MacMartin B. Kravitz P. B. Goddard |
| author_facet | D. Visioni E. M. Bednarz D. G. MacMartin B. Kravitz P. B. Goddard |
| author_sort | D. Visioni |
| collection | DOAJ |
| description | Abstract The specifics of the simulated injection choices in the case of stratospheric aerosol injections (SAI) are part of the crucial context necessary for meaningfully discussing the impacts that a deployment of SAI would have on the planet. One of the main choices is the desired amount of cooling that the injections are aiming to achieve. Previous SAI simulations have usually either simulated a fixed amount of injection, resulting in a fixed amount of warming being offset, or have specified one target temperature, so that the amount of cooling is only dependent on the underlying trajectory of greenhouse gases. Here, we use three sets of SAI simulations achieving different amounts of global mean surface cooling while following a middle‐of‐the‐road greenhouse gas emission trajectory: one SAI scenario maintains temperatures at 1.5°C above preindustrial levels (PI), and two other scenarios which achieve additional cooling to 1.0°C and 0.5°C above PI. We demonstrate that various surface impacts scale proportionally with respect to the amount of cooling, such as global mean precipitation changes, changes to the Atlantic Meridional Overturning Circulation and to the Walker Cell. We also highlight the importance of the choice of the baseline period when comparing the SAI responses to one another and to the greenhouse gas emission pathway. This analysis leads to policy‐relevant discussions around the concept of a reference period altogether, and to what constitutes a relevant, or significant, change produced by SAI. |
| first_indexed | 2024-03-12T12:29:03Z |
| format | Article |
| id | doaj.art-ca66bbe7f87b4761a675699ee20554a2 |
| institution | Directory Open Access Journal |
| issn | 2328-4277 |
| language | English |
| last_indexed | 2024-03-12T12:29:03Z |
| publishDate | 2023-08-01 |
| publisher | Wiley |
| record_format | Article |
| series | Earth's Future |
| spelling | doaj.art-ca66bbe7f87b4761a675699ee20554a22023-08-29T18:52:31ZengWileyEarth's Future2328-42772023-08-01118n/an/a10.1029/2023EF003851The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol InjectionD. Visioni0E. M. Bednarz1D. G. MacMartin2B. Kravitz3P. B. Goddard4Department of Earth and Atmospheric Sciences Cornell University Ithaca NY USACooperative Institute for Research in Environmental Sciences (CIRES) University of Colorado Boulder Boulder CO USASibley School of Mechanical and Aerospace Engineering Cornell University Ithaca NY USADepartment of Earth and Atmospheric Sciences Indiana University Bloomington IN USADepartment of Earth and Atmospheric Sciences Indiana University Bloomington IN USAAbstract The specifics of the simulated injection choices in the case of stratospheric aerosol injections (SAI) are part of the crucial context necessary for meaningfully discussing the impacts that a deployment of SAI would have on the planet. One of the main choices is the desired amount of cooling that the injections are aiming to achieve. Previous SAI simulations have usually either simulated a fixed amount of injection, resulting in a fixed amount of warming being offset, or have specified one target temperature, so that the amount of cooling is only dependent on the underlying trajectory of greenhouse gases. Here, we use three sets of SAI simulations achieving different amounts of global mean surface cooling while following a middle‐of‐the‐road greenhouse gas emission trajectory: one SAI scenario maintains temperatures at 1.5°C above preindustrial levels (PI), and two other scenarios which achieve additional cooling to 1.0°C and 0.5°C above PI. We demonstrate that various surface impacts scale proportionally with respect to the amount of cooling, such as global mean precipitation changes, changes to the Atlantic Meridional Overturning Circulation and to the Walker Cell. We also highlight the importance of the choice of the baseline period when comparing the SAI responses to one another and to the greenhouse gas emission pathway. This analysis leads to policy‐relevant discussions around the concept of a reference period altogether, and to what constitutes a relevant, or significant, change produced by SAI.https://doi.org/10.1029/2023EF003851climate interventionSRMclimate impactsstratospheric aerosols |
| spellingShingle | D. Visioni E. M. Bednarz D. G. MacMartin B. Kravitz P. B. Goddard The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol Injection Earth's Future climate intervention SRM climate impacts stratospheric aerosols |
| title | The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol Injection |
| title_full | The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol Injection |
| title_fullStr | The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol Injection |
| title_full_unstemmed | The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol Injection |
| title_short | The Choice of Baseline Period Influences the Assessments of the Outcomes of Stratospheric Aerosol Injection |
| title_sort | choice of baseline period influences the assessments of the outcomes of stratospheric aerosol injection |
| topic | climate intervention SRM climate impacts stratospheric aerosols |
| url | https://doi.org/10.1029/2023EF003851 |
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