SIMIP is an endorsed diagnostic MIP for CMIP6 that defines a list of variables to understand the evolution of sea ice in any experiment using the sea ice model as part of CMIP6.
These variables allow researchers to analyze the three budgets that govern the evolution of sea ice and its impact on the Earth’s climate system, namely conservation of heat, the momentum balance and tracer conservation. In addition, variables are included that allow for the high frequency analysis of the sea-ice state itself.
The endorsed variable list updates and unifies some of the definitions included in CMIP5 to more closely resemble the actual physical quantity (e.g., sea ice thickness). In addition, it includes new variables that are needed for an in-depth understanding of sea-ice evolution in CMIP6 simulations. The list was initiated at the 2014 Large scale sea ice Modeling workshop in Reading, UK, organized by the CliC Sea Ice and Climate Modeling forum and then later refined by the co-Chairs of SIMIP and the SIMIP SSG.
Community feedback on the list of variables were sollicited by March 31st 2015, so they could be included in the final SIMIP data request for CMIP6. Please send any suggestions of missing variables, errors, unclear definitions, etc to the SIMIP co-chairs Dirk Notz and Alex Jahn by email.
The main achievement of the CliC sea ice and climate modelling forum in 2015 was the endorsement of our CMIP5 Sea-Ice Model Intercomparison Project SIMIP by the CMIP6 panel. SIMIP aims at establishing a new standard for sea-ice related output from coupled climate models which will allow us to understand the evolution of sea-ice in large scale models with a much stronger focus on individual processes than has ever been possible before.
This new standard was established through ample consultation with the international sea-ice modeling community that was initiated by a workshop in Reading in 2014 and continued via email exchanges throughout much of 2015.
The new protocol was discussed and coordinated with other endorsed CMIP6 MIPs at the CMIP6 workshop in Dubrovnik in September 2015. Throughout the year, the SIMIP leads were closely involved in the establishment of the final CMIP6 data call that is coordinated by Martin Juckes at the NCAS British Atmospheric Data Centre. They were in particular involved in ensuring consistency of all sea-ice related variables across all MIPs, and in ensuring consistency with the CF standard of climate variables.
In 2016, SIMIP will continue its series of workshops with a workshop that will bring sea-ice modelling and sea-ice observing expertise together. Through this workshop, the SIMIP leads hope that both communities will better be able to understand the needs of the other, and will establish the most efficient pathway for joining the insights of modelers and observationalists in better understanding the past and future evolution of sea ice.
2017 SIMIP workshop
The 2017 SIMIP workshop (March 29th noon - March 30th noon) is devoted to discussions about the sea ice simulations from the upcoming CMIP6 experiments (SIMIP), with three distinct aims:
1. To discuss and define best practices for the evaluation of sea-ice simulations against observations
2. To identify and define new remote sensing and in situ sea ice observations that will allow for improved model evaluation and initialization
3. To discuss and coordinate the analysis of CMIP6 sea ice simulations for improved understanding of sea ice processes and improved sea ice projections.
The SIMIP workshop is organized jointly with the Polar Prediction workshop, and will take place in Bremerhaven, Germany from March 27th to 30th March 2017. More information and the registration form (due by Jan 30th 2017) can be found here:
Observations for sea ice model evaluation
The National Snow and Ice Data Center (NSIDC) maintains a list of sea-ice related observational records that can be used to analyse the performance of sea-ice model simulations: http://nsidc.org/data/sipn/data-sets.html
The NCAR ClimateDataGuide also features some sea ice products (in particular sea ice concentrations), with expert guidance on their properties for some of these data records: https://climatedataguide.ucar.edu/
CMIP6 Data Request Document: https://earthsystemcog.org/projects/wip/CMIP6DataRequest (Spreadsheet view of the variable definitions)
Ongoing CMIP6 sea ice analysis projects:
To coordinate the analysis of the requested sea ice output from CMIP6, please check the [list of existing SIMIP-related analysis projects], contact potential collaborators, and add your ongoing projects, and ultimately publications, to the list, by emailing the CliC Project Office (info[a]climate-cryosphere.org).
SIMIP co-chairs: Dirk Notz (MPI Hamburg) and Alexandra Jahn (University of Colorado at Boulder)
SIMIP SSG: Marika Holland, Elizabeth Hunke, François Massonnet, Julienne Stroeve, Bruno Tremblay, Martin Vancoppenolle