DOI: 10.5061/dryad.sbcc2frfx
title: Long-term climate impacts of large stratospheric water vapor perturbations: Postprocessed MiMA data (Part 2)

description: The amount of water vapor injected into the stratosphere after the
 eruption of Hunga Tonga-Hunga Ha’apai (HTHH) was unprecedented, and it is
 therefore unclear what it might mean for surface climate. We use chemistry
 climate model simulations to assess the long-term surface impacts of
 stratospheric water vapor (SWV) anomalies similar to those caused by HTHH,
 but neglect the relatively minor aerosol loading from the eruption. The
 simulations show that the SWV anomalies lead to strong and persistent
 warming of Northern Hemisphere landmasses in boreal winter, and austral
 winter cooling over Australia, years after eruption, demonstrating that
 large SWV forcing can have surface impacts on a decadal timescale. We also
 emphasize that the surface response to SWV anomalies is more complex than
 simple warming due to greenhouse forcing and is influenced by factors such
 as regional circulation patterns and cloud feedbacks. Further research is
 needed to fully understand the multi-year effects of SWV anomalies and
 their relationship with climate phenomena like El Nino Southern
 Oscillation.
description: # Long-term climate impacts of large stratospheric water vapor
 perturbations: Postprocessed MiMA data
 [https://doi.org/10.5061/dryad.sbcc2frfx](https://doi.org/10.5061/dryad.sbcc2frfx) This is data used for the paper Jucker, M., C. Lucas, and D. Dutta, 2024: Long-term climate impacts of large stratospheric water vapor perturbations. J. Climate, doi [10.1175/JCLI-D-23-0437.1](https://doi.org/10.1175/JCLI-D-23-0437.1) ## File structure The filenames follow a simple structure which is: `_ [+ _] [+ season_] + {ctrl,pert,delta}_ + ens.nc` This encodes the following information: * `_` means the data comes from MiMA, and corresponds to one of the following experiments: * `bench_SH_` refers to the Southern Hemisphere benchmark setup of MiMA introduced by [Garfinkel et al. (2021)](https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020GL092321). This is the case for all files. * `fix_125Tg_` means both ozone and water vapor have been fixed to the WACCM simulations. * `fixq_o3init_125Tg_` means water vapor is fixed to WACCM simulations but ozone is fixed to climatology. * `fixo3_qinit_125Tg_` means ozone is fixed to WACCM simulations but water vapor is fixed to climatology. * `_` is optional and only present if only that one variable is contained in the file * `season_` is optional and denotes files which have been averaged over full seasons. If `season_` is not present, the data is monthly (default). * `{ctrl,pert,delta}_` indicates whether the data comes from the control (`ctrl`), or perturbation (`pert`) simulation. `delta` denotes files which are computed using `ncdiff` between the `pert` and `ctrl` simulations, i.e., they contain the differences between `pert` and `ctrl`. * `ens.nc` means that these files contain the full ensemble information, i.e. there is an additional dimension `member` which denotes the ensemble member. ## Individual files | File | Numerical setup | Data | | :---------------------------------------------------- | :-------------------------------------------------------------------------- | :------------------------------------------------ | | bench\_SH\_fixq\_o3init\_125Tg\_delta\_ens\_nc | water vapor is fixed to WACCM simulations but ozone is fixed to climatology | anomalies | | bench\_SH\_fixo3\_qinit\_125Tg\_season\_delta\_ens.nc | ozone is fixed to WACCM simulations but water vapor is fixed to climatology | seasonal anomalies | | bench\_SH\_fixq\_o3init\_125Tg\_season\_ctrl\_ens.nc | water vapor is fixed to WACCM simulations but ozone is fixed to climatology | seasonal control | | bench\_SH\_fixo3\_qinit\_125Tg\_season\_pert\_ens.nc | ozone is fixed to WACCM simulations but water vapor is fixed to climatology | seasonal perturbation | | bench\_SH\_fixq\_o3init\_125Tg\_season\_pert\_ens.nc | water vapor is fixed to WACCM simulations but ozone is fixed to climatology | seasonal perturbation | | bench\_SH\_fixq\_o3init\_125Tg\_season\_delta\_ens.nc | water vapor is fixed to WACCM simulations but ozone is fixed to climatology | seasonal anomalies | | bench\_SH\_fixo3\_qinit\_125Tg\_season\_ctrl\_ens.nc | ozone is fixed to WACCM simulations but water vapor is fixed to climatology | seasonal control | | bench\_SH\_fix\_125Tg\_season\_pert\_ens.nc | both ozone and water vapor have been fixed to the WACCM simulations | seasonal perturbation | | bench\_SH\_fix\_125Tg\_season\_delta\_ens.nc | both ozone and water vapor have been fixed to the WACCM simulations | seasonal anomalies | | bench\_SH\_fix\_125Tg\_season\_ctrl\_ens.nc | both ozone and water vapor have been fixed to the WACCM simulations | seasonal control | | bench\_SH\_fix\_125Tg\_cfld\_delta.nc | both ozone and water vapor have been fixed to the WACCM simulations | anomalies, downward longwave flux at 200hPa only | | bench\_SH\_fixq\_o3init\_125Tg\_pert\_ens.nc | water vapor is fixed to WACCM simulations but ozone is fixed to climatology | perturbation | | bench\_SH\_fixq\_o3init\_125Tg\_ctrl\_ens.nc | water vapor is fixed to WACCM simulations but ozone is fixed to climatology | control | | bench\_SH\_fixo3\_qinit\_125Tg\_pert\_ens.nc | ozone is fixed to WACCM simulations but water vapor is fixed to climatology | perturbation | | bench\_SH\_fixo3\_qinit\_125Tg\_ctrl\_ens.nc | ozone is fixed to WACCM simulations but water vapor is fixed to climatology | control | | bench\_SH\_fix\_125Tg\_pert\_ens.nc | both ozone and water vapor have been fixed to the WACCM simulations | perturbation | | bench\_SH\_fix\_125Tg\_delta\_ens.nc | both ozone and water vapor have been fixed to the WACCM simulations | anomalies | | bench\_SH\_fix\_125Tg\_ctrl\_ens.nc | both ozone and water vapor have been fixed to the WACCM simulations | control | | bench\_SH\_fix\_125Tg\_cfsd\_delta.nc | both ozone and water vapor have been fixed to the WACCM simulations | anomalies, downward shortwave flux at 200hPa only | Please see the [main data repository](https://doi.org/10.5061/dryad.0zpc8675t) for more information.