Committed sea-level rise under the Paris Agreement and the legacy of delayed mitigation action

• Main Authors: Mengel, M., Nauels, A., Rogelj, J., Schleussner, C.F.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2018
• Subjects: Antarctic; Antarc*; Ice Sheet
• Online Access: http://pure.iiasa.ac.at/id/eprint/15134/; http://pure.iiasa.ac.at/id/eprint/15134/1/s41467-018-02985-8.pdf; http://pure.iiasa.ac.at/id/eprint/15134/2/41467_2018_2985_MOESM1_ESM.pdf; http://pure.iiasa.ac.at/id/eprint/15134/9/41467_2018_2985_MOESM2_ESM.pdf; http://pure.iiasa.ac.at/id/eprint/15134/10/41467_2018_2985_MOESM3_ESM.docx

Sea-level rise is a major consequence of climate change that will continue long after emissions of greenhouse gases have stopped. The 2015 Paris Agreement aims at reducing climate-related risks by reducing greenhouse gas emissions to net zero and limiting global-mean temperature increase. Here we quantify the effect of these constraints on global sea-level rise until 2300, including Antarctic ice-sheet instabilities. We estimate median sea-level rise between 0.7 and 1.2 m, if net-zero greenhouse gas emissions are sustained until 2300, varying with the pathway of emissions during this century. Temperature stabilization below 2 °C is insufficient to hold median sea-level rise until 2300 below 1.5 m. We find that each 5-year delay in near-term peaking of CO2 emissions increases median year 2300 sea-level rise estimates by ca. 0.2 m, and extreme sea-level rise estimates at the 95th percentile by up to 1 m. Our results underline the importance of near-term mitigation action for limiting long-term sea-level rise risks.