Robust Multiyear Climate Impacts of Volcanic Eruptions in Decadal Prediction Systems

• Published in: Journal of Geophysical Research: Atmospheres
• Main Authors: Hermanson, Leon, Bilbao, Roberto, Dunstone, Nick, Ménégoz, Martin, Ortega Montilla, Pablo, Pohlmann, Holger, Robson, Jon I, Smith, Doug M., Strand, Gary, Timmreck, Claudia, Yeager, Steve, Danabasoglu, Gokhan
• Other Authors: Barcelona Supercomputing Center
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2020
• Subjects: Àrees temàtiques de la UPC::Desenvolupament humà i sostenible; Volcanoes; North Atlantic oscillation; Mathematical models; Volcanic eruptions; Decadal prediction systems; Climate prediction; Volcanic aerosols; Volcans; Erupcions volcàniques > Avaluació del risc; Models matemàtics; Archer; Pacific; North Atlantic
• Online Access: http://hdl.handle.net/2117/192942; https://doi.org/10.1029/2019JD031739

Major tropical volcanic eruptions have a large impact on climate, but there have only been three major eruptions during the recent relatively well‐observed period. Models are therefore an important tool to understand and predict the impacts of an eruption. This study uses five state‐of‐the‐art decadal prediction systems that have been initialized with the observed state before volcanic aerosols are introduced. The impact of the volcanic aerosols is found by subtracting the results of a reference experiment where the volcanic aerosols are omitted. We look for the robust impact across models and volcanoes by combining all the experiments, which helps reveal a signal even if it is weak in the models. The models used in this study simulate realistic levels of warming in the stratosphere, but zonal winds are weaker than the observations. As a consequence, models can produce a pattern similar to the North Atlantic Oscillation in the first winter following the eruption, but the response and impact on surface temperatures are weaker than in observations. Reproducing the pattern, but not the amplitude, may be related to a known model error. There are also impacts in the Pacific and Atlantic Oceans. This work contributes toward improving the interpretation of decadal predictions in the case of a future large tropical volcanic eruption. We thank the three reviewers for their help in improving this manuscript. The data are available from DOI (10.5281/zenodo.2613699). L. H. was supported by the Climate Resilience Project funded by UKRI. N. D. and D. M. S. were supported by the Met Office Hadley Centre Climate Programme funded by BEIS and Defra. M. M., R. B., and P. O. received funding from the Ministerio de Economia y Competitividad (MINECO) as part of the VOLCADEC (Ref. CGL2015‐70177‐R) and HIATUS (Ref. CGL2015‐70353‐R) projects. H. P. and C. T. were supported by the German Ministry of Education and Research (BMBF) under the project MiKlip (Grants 01LP1519A and 01LP1517B). J. I. R. was supported by the Natural Environmental Research Council (NERC)‐funded SMURPHS project and the ACSIS program. HiGEM‐DP experiments were performed using the ARCHER UK National Supercomputing Service (http://www.archer.ac.uk). The National Center for Atmospheric Research (NCAR) is a major facility sponsored by the U.S. National Science Foundation (NSF) under Cooperative Agreement No. 1852977. G. D. and S. Y. further acknowledge the support of NSF Collaborative Research EaSM2 Grant OCE‐1243015. G. S. was supported by the Regional and Global Climate Modeling Program (RGCM) of the U.S. Department of Energy's, Office of Science (BER), Cooperative Agreement DE‐FC02‐97ER62402. Peer Reviewed Postprint (published version)