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.

  • Basic analysis of global-mean-temperature levels in the ISIMIP2b climate data can be found here.

ISIMIP2b Protocol Changes

July 20, 2017

In addition to small corrections in other parts of the protocol, the terrestrial biodiversity sector was added.

May 23, 2017

Further specificiations have been added to the lakes protocol, which is now included as a sub-chapter of Water. In the forest protocol, the management specifications have been updated, and some variable-names corrected.

March 3, 2017

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

March 3, 2017

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


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

June 13, 2017

References for the four observational climate data sets for ISIMIP2a have been added to table 3.

May 22, 2017

Changes include updates to the management schedules (table 26) and correction of the definition of output variables.

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 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.

ISIMIP Fast Track

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

Important information about preparing your simulation files