The ISA-MIP model intercomparison

The SPARC activity, “Stratospheric Sulfur and its Role in Climate” was initiated to coordinate international research activities on modelling and observation of stratospheric sulfate aerosols (and precursor gases) in order to assess its climate forcing and feedback

An interactive stratospheric aerosol model intercomparison “ISA-MIP” has been established in the frame of SSIRC. ISA-MIP will compare interactive stratospheric aerosol models using a range of satellite and in situ observations to constrain and improve the models and to provide a sound scientific basis for future work.

The 4 experiments in ISA-MIP are designed to address the main processes that determine the stratospheric sulfate aerosol load and size distribution and the associated optical properties. The guiding questions are listed on the right. A detailed overview about the experiment details is given here.

The Questions

1.  How large is the stratospheric sulfate load under volcanically quiescent conditions and how sensitive is it to microphysical parameterizations and transport processes? (Opens internal link in current windowBG)

2.  Can we explain the sources and pathways of the observed trend in the stratospheric aerosol load over the last decade?  (Opens internal link in current windowTAR

3.  Can stratospheric aerosol observations constrain uncertainties in the initial sulfur injection amount and altitude distribution of the three largest volcanic eruptions of the last 100 years?  (Opens internal link in current windowHerSEA

4.  What is the confidence interval for volcanic forcings simulated by interactive stratospheric aerosol models and which parameter uncertainties are the predictions most sensitive to? (Opens internal link in current windowPoEMS


Opens external link in new windowLink to the GMD  paper



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