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Geoscientific Model Development









The Stratospheric Sulfur and its Role in Climate (SSiRC) Interactive Stratospheric Aerosol Model Intercomparison Project (ISA-MIP) explores uncertainties in the processes that connect volcanic emission of sulfur gas species and the radiative forcing associated with the resulting enhancement of the stratospheric aerosol layer. The central aim of ISA-MIP is to constrain and improve interactive stratospheric aerosol models and reduce uncertainties in the stratospheric aerosol forcing by comparing results of standardized model experiments with a range of observations. In this paper we present four co-ordinated inter-model experiments designed to investigate key processes which influence the formation and temporal development of stratospheric aerosol in different time periods of the observational record. The Background (BG) experiment will focus on microphysics and transport processes under volcanically quiescent conditions, when the stratospheric aerosol is controlled by the transport of aerosols and their precursors from the troposphere to the stratosphere. The Transient Aerosol Record (TAR) experiment will explore the role of small- to moderate-magnitude volcanic eruptions, anthropogenic sulfur emissions, and transport processes over the period 1998–2012 and their role in the warming hiatus. Two further experiments will investigate the stratospheric sulfate aerosol evolution after major volcanic eruptions. The Historical Eruptions SO2 Emission Assessment (HErSEA) experiment will focus on the uncertainty in the initial emission of recent large-magnitude volcanic eruptions, while the Pinatubo Emulation in Multiple models (PoEMS) experiment will provide a comprehensive uncertainty analysis of the radiative forcing from the 1991 Mt Pinatubo eruption.


Claudia Timmreck1, Graham W. Mann2,3, Valentina Aquila4, Rene Hommel5,a, Lindsay A. Lee2, Anja Schmidt6,7, Christoph Brühl8, Simon Carn9, Mian Chin10, Sandip S. Dhomse2, Thomas Diehl11, Jason M. English12,13, Michael J. Mills14, Ryan Neely2,3, Jianxiong Sheng15,16, Matthew Toohey1,17, and Debra Weisenstein16

1Max-Planck-Institute for Meteorology, Hamburg, Germany
2School of Earth and Environment, University of Leeds, Leeds, UK
3UK National Centre for Atmospheric Science, University of Leeds, Leeds, UK
4American University, Dept. of Environmental Science, Washington, DC, USA
5Institute of Environmental Physics, University of Bremen, Bremen, Germany
6Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
7Department of Geography, University of Cambridge, Downing Place, Cambridge, CB2 3EN, UK
8Max-Planck-Institute for Chemistry, Mainz, Germany
9Dept. Geo. Min. Eng. Sci. MTU, Houghton, MI, USA
10NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
11Directorate for Sustainable Resources, Joint Research Centre, European Commission, Ispra, Italy
12University of Colorado, Cooperative Institute for Research in Environmental Sciences, Boulder, CO, USA
13NOAA Earth Systems Laboratory, Boulder, CO, USA
14Atmospheric Chemistry Observations and Modeling, National Center for Atmospheric Research, Boulder, CO, USA
15ETHZ, Zurich, Switzerland
16John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
17GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany
anow at: Hommel & Graf Environmental, Hamburg, Göttingen, Germany

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This work is licensed under a Creative Commons Attribution 4.0 License.