Global temperature goals should determine the time horizons for greenhouse gas emission metrics
Emission metrics, a crucial tool in setting effective exchange rates between greenhouse gases, currently require an arbitrary choice of time horizon. Here, we propose a novel framework to calculate the time horizon that aligns with scenarios achieving a specific temperature goal. We analyze the Inte...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2022-01-01
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| Series: | Environmental Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1748-9326/ac4940 |
| _version_ | 1827869559043915776 |
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| author | Sam Abernethy Robert B Jackson |
| author_facet | Sam Abernethy Robert B Jackson |
| author_sort | Sam Abernethy |
| collection | DOAJ |
| description | Emission metrics, a crucial tool in setting effective exchange rates between greenhouse gases, currently require an arbitrary choice of time horizon. Here, we propose a novel framework to calculate the time horizon that aligns with scenarios achieving a specific temperature goal. We analyze the Intergovernmental Panel on Climate Change Special Report on Global Warming of 1.5 °C Scenario Database to find that time horizons aligning with the 1.5 °C and 2 °C global warming goals of the Paris Agreement are 24 [90% prediction interval: 7, 41] and 58 [90% PI: 41, 74] years, respectively. We then use these time horizons to quantify time-dependent emission metrics for methane. We find that the Global Warming Potential (GWP) values that align with the 1.5 °C and 2 °C goals are GWP _1.5 °C = 75 [90% PI: 54, 107] and GWP _2 °C = 42 [90% PI: 35, 54]. For the Global Temperature change Potential (GTP) they are GTP _1.5 °C = 41 [90% PI: 16, 102] and GTP _2 °C = 9 [90% PI: 7, 16]. The most commonly used time horizon, 100 years, underestimates methane’s GWP and GTP by 34% and 38%, respectively, relative to the values we calculate that align with the 2 °C goal and by 63% and 87%, respectively, relative to the 1.5 °C goal. To best align emission metrics with the Paris Agreement 1.5 °C goal, we recommend a 24 year time horizon, using 2045 as the endpoint time, with its associated GWP _1.5 °C = 75 and GTP _1.5 °C = 41. |
| first_indexed | 2024-03-12T15:46:56Z |
| format | Article |
| id | doaj.art-5b5acb193dbf40a7b4d40171f03c04d1 |
| institution | Directory Open Access Journal |
| issn | 1748-9326 |
| language | English |
| last_indexed | 2024-03-12T15:46:56Z |
| publishDate | 2022-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | Environmental Research Letters |
| spelling | doaj.art-5b5acb193dbf40a7b4d40171f03c04d12023-08-09T15:23:39ZengIOP PublishingEnvironmental Research Letters1748-93262022-01-0117202401910.1088/1748-9326/ac4940Global temperature goals should determine the time horizons for greenhouse gas emission metricsSam Abernethy0https://orcid.org/0000-0002-3565-7243Robert B Jackson1https://orcid.org/0000-0001-8846-7147Department of Applied Physics, Stanford University , Stanford, CA, United States of America; Department of Earth System Science, Stanford University , Stanford, CA, United States of AmericaDepartment of Earth System Science, Stanford University , Stanford, CA, United States of America; Woods Institute for the Environment and Precourt Institute for Energy, Stanford University , Stanford, CA, United States of AmericaEmission metrics, a crucial tool in setting effective exchange rates between greenhouse gases, currently require an arbitrary choice of time horizon. Here, we propose a novel framework to calculate the time horizon that aligns with scenarios achieving a specific temperature goal. We analyze the Intergovernmental Panel on Climate Change Special Report on Global Warming of 1.5 °C Scenario Database to find that time horizons aligning with the 1.5 °C and 2 °C global warming goals of the Paris Agreement are 24 [90% prediction interval: 7, 41] and 58 [90% PI: 41, 74] years, respectively. We then use these time horizons to quantify time-dependent emission metrics for methane. We find that the Global Warming Potential (GWP) values that align with the 1.5 °C and 2 °C goals are GWP _1.5 °C = 75 [90% PI: 54, 107] and GWP _2 °C = 42 [90% PI: 35, 54]. For the Global Temperature change Potential (GTP) they are GTP _1.5 °C = 41 [90% PI: 16, 102] and GTP _2 °C = 9 [90% PI: 7, 16]. The most commonly used time horizon, 100 years, underestimates methane’s GWP and GTP by 34% and 38%, respectively, relative to the values we calculate that align with the 2 °C goal and by 63% and 87%, respectively, relative to the 1.5 °C goal. To best align emission metrics with the Paris Agreement 1.5 °C goal, we recommend a 24 year time horizon, using 2045 as the endpoint time, with its associated GWP _1.5 °C = 75 and GTP _1.5 °C = 41.https://doi.org/10.1088/1748-9326/ac4940emissionsemission metricstime horizonsmethanecarbon dioxideParis Agreement |
| spellingShingle | Sam Abernethy Robert B Jackson Global temperature goals should determine the time horizons for greenhouse gas emission metrics Environmental Research Letters emissions emission metrics time horizons methane carbon dioxide Paris Agreement |
| title | Global temperature goals should determine the time horizons for greenhouse gas emission metrics |
| title_full | Global temperature goals should determine the time horizons for greenhouse gas emission metrics |
| title_fullStr | Global temperature goals should determine the time horizons for greenhouse gas emission metrics |
| title_full_unstemmed | Global temperature goals should determine the time horizons for greenhouse gas emission metrics |
| title_short | Global temperature goals should determine the time horizons for greenhouse gas emission metrics |
| title_sort | global temperature goals should determine the time horizons for greenhouse gas emission metrics |
| topic | emissions emission metrics time horizons methane carbon dioxide Paris Agreement |
| url | https://doi.org/10.1088/1748-9326/ac4940 |
| work_keys_str_mv | AT samabernethy globaltemperaturegoalsshoulddeterminethetimehorizonsforgreenhousegasemissionmetrics AT robertbjackson globaltemperaturegoalsshoulddeterminethetimehorizonsforgreenhousegasemissionmetrics |