Impact model: ACEA

ACEA is one of the 15 models following the ISIMIP3a/b protocol which form the base of simulations for the ISIMIP3a/b agricultural sector outputs.

For a full technical description of ACEA, see this DOI link: https://doi.org/10.1038/s41597-024-03051-3

For a full technical description of the ISIMIP3a Simulation Data from Agricultural Sector, see this DOI link: https://doi.org/10.5194/gmd-17-1-2024

ISIMIP3b
ISIMIP3a

Person responsible for model simulations in this simulation round

Oleksandr Mialyk: o.mialyk@utwente.nl, 0000-0002-7495-2325, University of Twente (Netherlands)

Additional persons involved: Han Su

Output Data

Experiments: ssp585_2015soc_default, ssp126_2015soc_default, historical_2015soc_default, picontrol_2015soc_default
Climate Drivers: MRI-ESM2-0, UKESM1-0-LL
Date: 2021-09-24

Basic information

Model Version: 2.0

Model Output License: CC0

Model Homepage: https://doi.org/10.5281/zenodo.10510934

Model License: Creative Commons Attribution 4.0 International

Simulation Round Specific Description: ACEA is one of the currently 15 models following the ISIMIP3a/b protocol which form the base of simulations for the ISIMIP3a/b agricultural sector outputs.

Reference Paper: Main Reference: Jägermeyr J, Müller C, et al. et al. Climate change signal in global agriculture emerges earlier in new generation of climate and crop models. Nature Food,None,,2021

Reference Paper: Other References: Mialyk O, Schyns J, Booij M, Hogeboom R et al. Historical simulation of maize water footprints with a new global gridded crop model ACEA. Hydrology and Earth System Sciences,26,923-940,2022

Resolution

Spatial aggregation: regular grid

Horizontal resolution: 0.5’ x 0.5’

Vertically resolved: Yes

Number of vertical layers: User-defined. Commonly 1 soil layer but divided into sub-layers for more accurate soil water balance calculation

Additional spatial aggregation & resolution information: 1D model so no lateral water flow

Temporal resolution of input data: climate variables: daily

Temporal resolution of input data: co2: annual

Temporal resolution of input data: land use/land cover: annual

Temporal resolution of input data: soil: constant

Input data

Simulated atmospheric climate data sets used: MRI-ESM2-0, UKESM1-0-LL

Emissions data sets used: Atmospheric composition (ISIMIP3b)

Other data sets used: Soil data (hwsd_soil_data_all_land, hwsd_soil_data_on_cropland)

Additional input data sets: Crop parameters are obtained from default AquaCrop files

Climate variables: hurs, sfcWind, tasmax, tasmin, rsds, pr

Spin-up

Was a spin-up performed?: No

Natural Vegetation

Natural vegetation partition: Not applicable

Natural vegetation dynamics: Not applicable

Natural vegetation cover dataset: Not applicable

Soil layers: One homogenous layer but divided into 8 sub-layers (for accurate soil water balance calculation)

Management & Adaptation Measures

Management: fully irrigated or rainfed

Key input and Management

Crops: Maize, spring and winter wheat, rice, and soya beans are provided but the model can simulate 30+ crops

Land cover: The whole land mask simulated

Planting date decision: Taken from GGMCI calendar but can be postponed to reach the soil moisture threshold for plant emergence.

Planting density: Global uniform depending on crop

Crop cultivars: Growing degree days calibrated on a grid cell basis according to the crop calendars and climate data from the period 1980-2009 (i.e. as in protocol).

Fertilizer application: Not applicable

Irrigation: Irrigation is applied if soil water content within the root zone is below field capacity

Crop residue: Not applicable

Initial soil water: Assumed 50% of TAW on the first day of simulation but for the subsequent growing seasons, it's generated based on soil water balance in the prior period.

Initial soil nitrate and ammonia: Not applicable

Initial soil c and om: Not applicable

Initial crop residue: Not applicable

Key model processes

Leaf area development: Expressed in dynamic green canopy cover ranging from 0 to 100% depending on phenology, heat & water stress, and planting density

Light interception: Not applicable

Light utilization: Not applicable

Yield formation: Estimated based on accumulated biomass and final harvest index. Biomass accumulation is calculated daily as a function of transpiration and water productivity. Harvest index reflects the harvestable fraction of biomass and is subject to water and heat stresses.

Crop phenology: Plant development includes several growing stages defined by the growing degree day thresholds.

Root distribution over depth: For annual crops, it increases from the planting date until a defined growing degree day threshold.

Stresses involved: Heat stress, cold stress, water deficit stress, aeration (waterlogging) stress

Type of water stress: Water deficiency stress slows canopy expansion, accelerates canopy senescence, decreases root deepening (but only if severe), reduces stomatal opening and transpiration, and affects harvest index. Waterlogging limits transpiration if soil is fully saturated for too long (number of days if crop-specific)

Type of heat stress: Cold temperature stress reduces biomass productivity. Hot or cold temperature stress inhibits pollination and reduces harvest index.

Water dynamics: Daily vertical water balance includes water input (precipitation, irrigation, and capillary rise) and output (runoff, evaporation, transpiration, and deep percolation) fluxes as well as upward and downward fluxes between soil sub-layers. Note that lateral fluxes are not considered.

Evapo-transpiration: Daily ET is calculated based on reference ET (estimated with Penman–Monteith equation), crop coefficients, and stomata/aeration stress coefficients.

Soil cn modeling: Not applicable

Co2 effects: CO2 concentration is used to calculate water productivity (needed to estimate crop biomass). Thus, with increasing CO2 water productivity increases as well, especially for C3 crops.

Methods for model calibration and validation

Parameters, number and description: Crop parameters are calibrated for each crop and provided by AquaCrop (See AquaCrop reference manual Annex I: https://www.fao.org/3/BR244E/br244e.pdf). In ACEA, we only adjust phenological development according to the GGCMI protocol.

Person responsible for model simulations in this simulation round

Oleksandr Mialyk: o.mialyk@utwente.nl, 0000-0002-7495-2325, University of Twente (Netherlands)

Output Data

Experiments: obsclim_2015soc_default
Climate Drivers: GSWP3-W5E5
Date: 2022-03-10

Basic information

Model Output License: CC0

Simulation Round Specific Description: * Data in embargo period, not yet publicly available. ACEA is one of the currently 15 models following the ISIMIP3a/b protocol which form the base of simulations for the ISIMIP3a/b agricultural sector outputs; for a full technical description of the ISIMIP3a Simulation Data from Agricultural Sector, see this DOI link: https://egusphere.copernicus.org/preprints/2023/egusphere-2023-281/