ISIMIP3a simulation round simulation protocol - Fisheries and Marine Ecosystems (global)

Introduction

General concept

The Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) provides a framework for the collation of a consistent set of climate impact data across sectors and scales. It also provides a unique opportunity for considering interactions between climate change impacts across sectors through consistent scenarios.

ISIMIP is intended to be structured in successive rounds connected to the different phases of the climate model intercomparison CMIP (ISIMIP Mission & Implementation document).

The main components of the ISIMIP framework are:

ISIMIP3a

Historical model evaluation and attribution runs

The ISIMIP3a part of the third round framework is dedicated to i) impact model evaluation and improvement and ii) detection and attribution of observed impacts according to the framework of IPCC AR5 Working Group II Chapter 18. To this end all simulations are forced by observed climate and socio-economic information and a de-trended version of the observed climate allowing for the generation of a “no climate change” baseline (counterfactual).

You can find the ISIMIP3b protocol, which is dedicated to a quantification of climate-related risks at different levels of climate change and socio-economic conditions, here.

Simulation protocol

In this protocol we describe the scenarios & experiments in ISIMIP3a simulation round, the different input datasets, the output variables, and how to report model results specifically for Fisheries and Marine Ecosystems (global). An overview of all sectors can be found at protocol.isimip.org.

Throughout the protocol we use specifiers that denote a particular scenario, experiment, variable or other parameter. We use these specifiers in the tables below, in the filenames of the input data sets, and ask you to use the same specifiers in your output files. More on reporting data can be found at the end of this document.

Model versioning

To ensure consistency between ISIMIP3a and ISIMIP3b as well as the different experiments within a simulation round, we require that modelling groups use the same version of an impact model for the experiments in ISIMIP3a and ISIMIP3b. If you cannot fulfill this, please indicate that by using a suffix for your model name (e.g. simple version numbering: MODEL-v1, MODEL-v2 or following semantic versioning: MODEL-2.0.0, see also reporting model results).

This versioning does not only apply to changes in the computational logic of the model, but also to input parameters, calibration or setup. If model versions are not reported, we will name them according to the simulation round (e.g. MODEL-isimip3a). We require the strict versioning to ensure that differences between model results are fully attributable to the changes in model forcings.

Scenarios & Experiments

Scenario definitions

Table 1: Climate scenario specifiers (climate-scenario).
Scenario specifier Description
obsclim Observed climate and CO₂ forcing used for model evaluation and the detection and attribution task.
spinclim Detrended version of the observed climate forcing used to spin-up the simulations based on a stable 1900 climate (see explanation below for details regarding the design of the spin-up)
counterclim Detrended version of the observed climate forcing used for the "no climate change" baseline simulations in the context of the detection and attributions task.
Table 2: Socio-economic scenario specifiers (soc-scenario).
Scenario specifier Description
histsoc

Varying direct human influences in the historical period (1850-2014) (e.g. observed changes in historical land use, nitrogen deposition and fertilizer input, fishing effort).

Please label your model run histsoc even if it only partly accounts for varying direct human forcings while another part of the the direct human forcing is considered constant or is ignored.

2015soc

Fixed year-2015 direct human influences (e.g. land use, nitrogen deposition and fertilizer input, fishing effort).

Please label your simulations 2015soc if they do not at all account for historical changes in direct human forcing, but they do represent constant year-2015 levels of direct human forcing for at least some direct human forcings.

nat

No direct human influences (naturalized run).

Please only label your model run nat if it does not at all account for any direct human forcings, including e.g. human land use.

Table 3: Sensitivity scenario specifiers (sens-scenario).
Scenario specifier Description
default For all experiments other than the sensitivity experiments.

General note regarding sensitivity experiments

The sensitivity experiments are meant to be "artificial" deviations from the default settings. So for example if your model does not at all account for changes in CO₂ concentrations (no option to switch it on or off) the run should be labeled as “default” in the sensitivity specifier of the file name even if the run would be identical to the 1901co2 sensitivity setting.

The particular sensitivity scenario for an experiment is given in the experiments table below. For most experiments no sensitivity scenario is given, so the default label applies.

Experiments

Table 4: Experiment set-up: Each experiment is specified by the climate forcing (CF) and the Direct Human Forcing (DHF).
Experiment Short description

Transition from Spin-up to experiment

1850-1900, only if spin-up is needed

Historical

1901-2018

model evaluation

histsoc

1st priority

CF: No climate change before 1901, observed forcing afterwards; constant 1850 levels of CO₂ before 1850 and based on observations afterwards

spinclim

obsclim

DHF: Fixed 1850 levels of direct human forcing before 1850, varying direct human influences according to observations afterwards

histsoc

histsoc

model evaluation

2015soc

1st priority

CF: No climate change before 1901, observed forcing afterwards; constant 1850 levels of CO₂ before 1850 and based on observations afterwards

spinclim

obsclim

DHF: Fixed 2015 levels of direct human forcing for the entire time period

2015soc

2015soc

model evaluation

nat

2nd priority

CF: No climate change before 1901, observed forcing afterwards; 1850 levels of CO₂ before 1850 and based on observations afterwards

spinclim

obsclim

DHF: No direct human influences

nat

nat

counterfactual climate

histsoc

1st priority

CF: de-trended observational climate forcing (counterfactual "no climate change" situation) + fixed CO₂ concentration at 1901 level "histsoc" version of the transition period of the model evaluation run

counterclim

DHF: 1850 levels of direct human forcing before 1850, varying direct human influences according to observations afterwards

histsoc

counterfactual climate

2015soc

1st priority

CF: de-trended observational climate forcing (counterfactual "no climate change" situation) "2015soc" version of the transition period of the model evaluation run

counterclim

DHF: fixed 2015 levels of direct human influences for the entire time period

2015soc

counterfactual climate

nat

2nd priority

CF: de-trended observational climate forcing (counterfactual "no climate change" situation) + fixed CO₂ concentration at 1901 level "nat" version of the transition period of the model evaluation run

counterclim

DHF: No direct human influences

nat

CO₂ sensitivity

histsoc

2nd priority

CF: no climate change before 1901, observed forcing afterwards + fixed CO₂ concentration at 1901 level "histsoc" version of the transition period of the model evaluation run

obsclim

Sensitivity scenario: 1901co2

DHF: 1850 levels of direct human forcing before 1850, varying direct human influences according to observations afterwards

histsoc

CO₂ sensitivity

2015soc

2nd priority

CF: no climate change before 1901, observed forcing afterwards + fixed CO₂ concentration at 1901 level "2015soc" version of the transition period of the model evaluation run

obsclim

Sensitivity scenario: 1901co2

DHF: fixed 2015 levels of direct human influences for the entire time period

2015soc

Note regarding models requiring spin-up

For models requiring spin-up, we provide 100 years of spinclim data which is identical with the first 100 years of the counterclim data (files climate/atmosphere/spinclim/<dataset>/<dataset>_spinclim_<variable>_global_daily_<start-year>_<start-year>.nc). If more than 100 years of spin-up are needed, these data can be repeated as often as needed. Use historical CO2 concentration and varying DHF, for the transition period from spin-up to the start of the experiment (1850-1900). When using a longer spin-up period that (nominally) extends back further than 1850, please keep CO2 concentration and DHF constant at 1850 level until reaching the year corresponding to 1850.

Input data

The base directory for input data at DKRZ is:

/work/bb0820/ISIMIP/ISIMIP3a/InputData/

Further information on accessing ISIMIP data can be found at ISIMIP - getting started.

Some of the datasets are tagged as mandatory. This does not mean that the data must be used in all cases, but if your models uses input data of this kind, we require to use the specified dataset. If an alterntive data set is used instead, we cannot consider it an ISIMIP simulation. If the mandatory label is not given, you may use alternative data (please document this clearly).

Climate forcing

Table 5: Climate and climate-related forcing data (climate-forcing).
Title Specifier Time period Reanalysis Bias adjustment target Comments
GSWP3-W5E5 gswp3-w5e5 1901-2016 ERA5 GPCC, CRU Combination of W5E5 for 1979-2016 with GSWP3 homogenized to W5E5 for 1901-1978. The homogenization reduces discontinuities at the 1978/1979 transition and was done using the ISIMIP3BASD v2.4.1 bias adjustment method.
GSWP3 gswp3 1901-2010 20CR GPCC, GPCP, CPC-Unified, CRU, SRB Dynamically downscaled and bias-adjusted 20th Century Reanalysis (20CR) from the Global Soil Wetness Project Phase 3 (GSWP3).
Table 6: Climate forcing variables for ISIMIP3a simulations (climate-variable).
Variable Variable specifier Unit Resolution Datasets

The climate forcing input files can be found using the following pattern:

climate/atmosphere/<climate-scenario>/<climate-forcing>/<climate-forcing>_<climate-scenario>_<climate-variable>_global_daily_<start-year>_<end-year>.nc

Greenhouse gas forcing

Table 7: Greenhouse gas forcing for ISIMIP3a simulation round.
Variable Variable specifier Unit Resolution Datasets
Atmospheric composition mandatory

Atmospheric CO2 concentration

composition_atmosphere/co2/co2_historical_annual_1850_2018.txt
co2 ppm
  • global
  • annual

Meinshausen et al. (2011) for 1850-2005 and Dlugokencky & Tans (2019) from 2006-2018.

Socioeconomic forcing

Table 8: Socioeconomic datasets for ISIMIP3a simulation round.
Dataset Included variables (specifier) Covered time period Resolution Reference/Source and Comments
Fishing mandatory

Fishing effort

Please contact the sectoral coordinators of the marine ecosystems and fisheries sector to gain access to this data.
  • fishing effort
  • 1950-2014
  • Marine ecosystems or exclusive economic zones
  • annual

Sea Around Us Project (SAUP; http://www.seaaroundus.org). Data can currently not be hosted on ISIMIP servers; for access please contact the sectoral coordinators of the marine ecosystems and fisheries sector.

Fish catch

Please contact the sectoral coordinators of the marine ecosystems and fisheries sector to gain access to this data.
  • fish catch
  • 1950-2014
  • Marine ecosystems or exclusive economic zones
  • annual

Regional Fisheries Management Organizations (RFMOs; https://ec.europa.eu/fisheries/cfp/international/rfmo_en) and/or local fisheries agencies. Data can currently not be hosted on ISIMIP servers; for access please contact the sectoral coordinators of the marine ecosystems and fisheries sector.

Population mandatory

Population 5' grid

socioeconomic/pop/<soc_scenario>/population_<soc_scenario>_5arcmin_annual_<start-year>_<end-year>.nc
  • total number of people (popc)
  • rural number of people (rurc)
  • urban number of people (urbc)
  • 1850-1900
  • 1901-2020
  • 5' grid
  • annual

HYDE v3.2.1 (Klein Goldewijk et al., 2017). Decadal data prior to year 2000 have been linearly interpolated in time.

Population 0.5° grid

socioeconomic/pop/<soc_scenario>/population_<soc_scenario>_30arcmin_annual_<start-year>_<end-year>.nc
  • total number of people (popc)
  • rural number of people (rurc)
  • urban number of people (urbc)
  • 1850-1900
  • 1901-2020
  • 0.5° grid
  • annual

HYDE v3.2.1 (Klein Goldewijk et al., 2017). Decadal data prior to year 2000 have been linearly interpolated in time. Aggregated to 0.5° spatial resolution

Population national

socioeconomic/pop/<soc_scenario>/population_<soc_scenario>_national_annual_<start-year>_<end-year>.csv
  • total number of people per country
  • 1850-1900
  • 1901-2020
  • national
  • annual

HYDE v3.2.1 (based on WPP 2017 revision, following the methodology of Klein Goldewijk et al., 2017). Decadal data prior to year 1950 have been linearly interpolated in time.

GDP mandatory

GDP

socioeconomic/gdp/<soc_scenario>/<soc_scenario>_gdp_annual_<start-year>_<end-year>.nc
  • GDP PPP 2005 USD (gdp)
  • 1850-1900
  • 1901-2016
  • country-level
  • annual

Historic country-level GDP data are an extension of the data provided by Geiger, 2018 (https://www.earth-syst-sci-data.net/10/847/2018/essd-10-847-2018.html), and are derived mainly from the Maddison Project database. Gridded GDP data will be provided by c. 07/2021.

Geographic data and information

Table 9: Geographic data and information for ISIMIP3a simulation round.
Dataset Included variables (specifier) Resolution Reference/Source and Comments
Land/Sea masks

landseamask

geo_conditions/landseamask/landseamask.nc
  • land-sea mask (mask)
0.5° grid

This is the land-sea mask of the W5E5 dataset. Over all grid cells marked as land by this mask, all climate data that are based on W5E5 (GSWP3-W5E5 as well as climate data bias-adjusted using W5E5) are guaranteed to represent climate conditions over land.

landseamask_no-ant

geo_conditions/landseamask/landseamask_no-ant.nc
  • land-sea mask (mask)
0.5° grid

Same as landseamask but without Antarctica.

landseamask_water-global

geo_conditions/landseamask/landseamask_water-global.nc
  • land-sea mask (mask)
0.5° grid

This is the generic land-sea mask from ISIMIP2b that is to be used for global water simulations in ISIMIP3. It marks more grid cells as land than landseamask. Over those additional land cells, the climate data that are based on W5E5 (GSWP3-W5E5 as well as climate data bias-adjusted using W5E5) are not guaranteed to represent climate conditions over land. Instead they may represent climate conditions over sea or a mix of conditions over land and sea.

Output data

Output variables

Table 10: Output variables for Fisheries and Marine Ecosystems (global) (variable).
Variable Variable specifier Unit Dimensions Resolution Comments
Mandatory output from global and regional models (provide as many as possible)
TOTAL system biomass density tsb g C m-2
  • 0.5° grid
  • monthly

all primary producers and consumers

TOTAL consumer biomass density tcb g C m-2
  • 0.5° grid
  • monthly

all consumers (trophic level >1, vertebrates and invertebrates)

Biomass density of consumers >10cm b10cm g C m-2
  • 0.5° grid
  • monthly

if L infinity is >10 cm, include in >10 cm class

Biomass density of consumers >30cm b30cm g C m-2
  • 0.5° grid
  • monthly

if L infinity is >30 cm, include in >30 cm class

TOTAL Catch (all commercial functional groups / size classes) tc g m-2
  • 0.5° grid
  • monthly

catch at sea (commercial landings plus discards, fish and invertebrates)

TOTAL Landings (all commercial functional groups / size classes) tla g m-2
  • 0.5° grid
  • monthly

commercial landings (catch without discards, fish and invertebrates)

Optional output from global and regional models
Biomass density of commercial species bcom g C m-2
  • 0.5° grid
  • monthly

Discarded species not included (Fish and invertebrates)

Biomass density of large consumers >90cm and <100kg blarge g C m-2
  • 0.5° grid
  • monthly
Biomass density of medium consumers >30cm and <90cm bmed g C m-2
  • 0.5° grid
  • monthly
Biomass density of small consumers <30cm bsmall g C m-2
  • 0.5° grid
  • monthly
Biomass density (by functional group / size class) b-<class>-<group> g C m-2
  • 0.5° grid
  • monthly

Provide name of each size class () and functional group () used, and provide a definition of each class/group.

Catch of large consumers >90cm and <100kg clarge g m-2
  • 0.5° grid
  • monthly
Catch of medium consumers >30cm and <90cm cmed g m-2
  • 0.5° grid
  • monthly
Catch of small consumers <30cm csmall g m-2
  • 0.5° grid
  • monthly
Catch (by functional group / size class) c-<class>-<group> g m-2
  • 0.5° grid
  • monthly

Provide name of each size class () and functional group () used, and provide a definition of each class/group.

TOTAL Catch of consumers >10cm tc10cm g m-2
  • 0.5° grid
  • monthly
TOTAL Catch of consumers >30cm tc30cm g m-2
  • 0.5° grid
  • monthly

Reporting model results

The specification on how to submit the data, as well as further information and instructions are given on the ISIMIP website at:

https://www.isimip.org/protocol/preparing-simulation-files

It is important that you comply precisely with the formatting specified there, in order to facilitate the analysis of your simulation results in the ISIMIP framework. Incorrect formatting can seriously delay the analysis. The ISIMIP Team will be glad to assist with the preparation of these files if necessary.

File names consist of a series of identifier, separated by underscores. Things to note:

Please name the files in the Fisheries and Marine Ecosystems (global) sector according to the following pattern:

<model>_<climate-forcing>_<climate-scenario>_<soc-scenario>_<sens-scenario>_<variable>_<region>_<timestep>_<start-year>_<end-year>.nc

and replace the identifiers with the specifiers given in the tables of this document. Examples would be:

lpjml_gswp3_obsclim_histsoc_default_qtot_global_annual_1901_1910.nc
lpjml_gwsp3_counterclim_2015soc_1901co2_yield-mai-noirr_global_annual_2006_2010.nc

The following regular expression can be used to validate and parse the file name for the fisheries and marine ecosystems (global) sector:

(?P<model>[a-z0-9-+.]+)_(?P<climate_forcing>[a-z0-9-]+)_(?P<climate_scenario>[a-z0-9-]+)_(?P<soc_scenario>[a-z0-9-]+)_(?P<sens_scenario>[a-z0-9-]+)_(?P<variable>[a-z0-9]+)_(?P<region>(global))_(?P<timestep>[a-z0-9-]+)_(?P<start_year>\d{4})_(?P<end_year>\d{4}).nc

For questions or clarifications, please contact info@isimip.org or the data managers directly (isimip-data@pik‐potsdam.de) before submitting files.

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