B-WP1 - ALARM-II: Alert for LARge volcanic eruptions in Medium term climate prediction II

Project aims

Including volcanic forcing in the MiKlip prediction system has increased the prediction skill for global surface temperature (Timmreck et al., 2016). However, the regional impacts of volcanic forcing in particular on Northern Hemisphere (NH) winter climate which are controlled largely by dynamical changes are neither fully understood nor well represented in the current prediction system. ALARM-II will therefore explore and improve the representation of the climate response to aerosol perturbations caused by volcanic eruptions in the MiKlip prediction system, in order to prepare for future events and be able to forecast their effects immediately after a potential future eruption.

Project structure

ALARM II consists of three workpackages and is coordinated by Dr. Claudia Timmreck (MPI-M). Dr. Hauke Schmidt (MPI-M) and Prof. Dr. Kirstin Krüger (UiO), as an external partner, contribute to the project.

Tasks of the projects

  1. ALARM-II studies all seasons but focusses on NH winter climate for which the highest  regional uncertainty in mid-term climate prediction for Europe exists after a large volcanic eruption. NH winter climate responses to external forcing presumably depend on the preconditioning of the polar vortex and the resolution of the prediction system.
  2. ALARM-II investigates if seasonal and decadal predictions after a large volcanic eruption can be improved if volcanically induced ozone changes are taken into account.
  3. The Coupled Model Inter Comparison Phase 6 (CMIP6) experiments investigate the impact of future volcanic eruptions on seasonal and decadal predictions. ALARM-II plays a leading role in the planning,analysis and interpretation of these building on experience gained in MiKlip.


  • Recommendation regarding the applied model configuration for post-volcanic studies.
  • Improved understanding of the impact of model background state and variability on response to volcanic forcing.
  • Assessment of the impact of volcanically induced ozone changes on NH climate predictability.
  • Synthesis of the seasonal and decadal post-volcanic response in a multi-model framework.
  • Updated version of the MiKlip volcanic impact recipe.


Timmreck, C., H. Pohlmann, S. Illing and C. Kadow (2016). The impact of stratospheric volcanic aerosol on decadal scale predictability. Geophys. Res. Lett, 43, doi: 10.1002/2015GL067431.


MPI for Meteorology
Dr. Claudia Timmreck (PI)

Dr. Hauke Schmidt

University of Oslo
Prof. Dr. Kirstin Krüger

Tambora 1815 as a test case for high impact volcanic eruptions: Earth system effects

2016 - WIREs Clim Change 2016

Raible, C. C. | S. Brönnimann, R. Auchmann, P. Brohan, T.L. Frölicher, H.-F. Graf, P. Jones Phil, J. Luterbacher, S. Muthers, R. Neukom, A. Robock, S. Self, A. Sudrajat, C. Timmreck, and M. Wegmann

Stratospheric aerosol—Observations, processes, and impact on climate

2016 - Rev. Geophys., 54, 278–335

Kremser, S. L. W. | Thomason, M. von Hobe, M. Hermann T. Deshler, C. Timmreck, M. Toohey, A. Stenke, F. Prata, J. Schwarz, R. Weigel, S. Fueglistaler, J.-P. Vernier, B. Luo, H. Schlager, J. Barnes, J.-C. Antuna-Marrero, D. Fairlie, M. Palm, E. Mahieu, J. Notholt, M. Rex, R. Neely, C. Bingen, A. Bourassa, J. Plane, D. Klocke, S. Carn, C. Lieven, A. James, S. Borrmann, L. Rieger, T. Trickl, C. Wilson, and B. Meland

The impact of wave-mean flow interaction on the Northern Hemisphere polar vortex after tropical volcanic eruptions

2016 - JGR-Atmospheres, Vol. 121 (10), pp. 5281–5297

Bittner, M. | C. Timmreck, H. Schmidt, M. Toohey, and K. Krüger

Climatic and societal impacts of a volcanic double event at the dawn of the Middle Ages

2016 - Climatic Change, Vol. 136 (3), pp. 401–412

Toohey, M. | K. Krüger, M. Sigl, F. Stordal, and H. Svensen