Simulation Protocols


The ISIMIP2b scenarios are designed to elicit the contribution of climate change to impacts arising from low-emissions climate-change scenarios. Pre-industrial control runs are included to facilitate statistical comparison with a no-climate-change case.

The ISIMIP2b protocol covers several new sectors, including tropical cyclones, temperature-related mortality and lakes.

The scientific rationale for the scenario design is documented in a GMD discussions paper by Frieler, et al.

Please read the data and co-authorship policy and register your model for ISIMIP2b here.

Below you will always find the latest version of the simulation protocol. Changes compared to previous versions will be recorded in the change log.

  • Important information about preparing your simulation files can be found here.
  • Information about downloading the input data here.

  • Information about which input data are available can be found here.

ISIMIP2b Protocol Changes

March 3, 2017

The health (temperature-related mortality) and forest-sector protocols have been updated to reflect the latest plans in those sectors.

March 3, 2017

Additional specifications have been added to the regional and global water sector protocol to accommodate the simulation of lakes.

Jan. 30, 2017

Changes have been made to the health (temperature-related mortality) scenario table to reflect latest developments.

Jan. 30, 2017

A new file identifier <co2_scenario> has been added. This identifier should be set to co2 unless the experiment specifically requires the identifier 2005co2 (in this case that CO2 levels are kept constant at 2005 levels.A table of possible file identifier has been added to the end of section 3 of the protocol.


The simulation protocol contains all information necessary to run climate-impacts simulations consistent with other models participating in the current ISIMIP simulation round, ISIMIP2a. Here you will find the protocol for ISIMIP2a. Click on the link below for information about the ISIMIP Fast Track.

Information about accessing and transferring using the DKRZ server

Important information about preparing your simulation files

The protocol is divided into 7 chapters: chapters 1-6 contain important information for modellers in all sectors. Chapter 7 provides sector-specific instructions (can be downloaded separately below).  For any queries, get in touch.

See the table below for an up-to-date list of protocol changes.

ISIMIP2a Protocol Changes

March 3, 2017

The forest protocol has been updated to reflect the latest simulation specifications, including information about accessing input data.

Jan. 12, 2017

The <variable> identifier in the file name of your output data can also be used for information about the plant functional type (pft) in the biomes and permafrost sectors. The pft/species naming is model-specific and hence has to be reported in the impact-model database (see .

Jan. 12, 2017

The historical CO2 concentrations are also provided in the input data archive (historical_CO2_annual.txt) and are based on time series of global atmospheric CO2 concentrations from Meinshausen, Raper, & Wigley (2011) for 1765-2005 and Dlugokencky & Tan (2014) from 2006-2013.

Nov. 30, 2016

Managerment and regeneration rules have been updated for the forest sector.

ISIMIP Fast Track

See here for more information about the ISIMIP Fast Track, including the simulation protocol.

Important information about preparing your simulation files