Impact model: LPJmL5-7-10-fire

This model version combines recent changes to the default LPJmL version (5.7.10) with recent updates to the Spitfire model, that are not yet part of the default version of LPJmL. Compared to earlier rounds of ISIMIP, this version includes a representation of the nitrogen cycle. Note that this version differs from the LPJmL version used for the agriculture sector in ISIMIP 3a & 3b.

ISIMIP3b
ISIMIP3a

Person responsible for model simulations in this simulation round

Sebastian Ostberg: ostberg@pik-potsdam.de, 0000-0002-2368-7015, Potsdam Institute for Climate Impact Research (Germany)

Additional persons involved: Luke Oberhagemann, Maik Billing & Markus Drüke (Spitfire update)

Basic information

Reference Paper: Main Reference: Wirth S, Braun J, Heinke J, Ostberg S, Rolinski S, Schaphoff S, Stenzel F, von Bloh W, Müller C et al. Biological nitrogen fixation of natural and agricultural vegetation simulated with LPJmL 5.7.9. EGUsphere [preprint],None,,2024

Reference Paper: Other References: Oberhagemann L, Billing M, von Bloh W, Drüke M, Forrest M, Bowring S, Hetzer J, Ribalaygua Batalla J, Thonicke K et al. Sources of Uncertainty in the Global Fire Model SPITFIRE: Development of LPJmL-SPITFIRE1.9 and Directions for Future Improvements. EGUsphere [preprint],None,,2024

Person responsible for model simulations in this simulation round

Sebastian Ostberg: ostberg@pik-potsdam.de, 0000-0002-2368-7015, Potsdam Institute for Climate Impact Research (Germany)

Additional persons involved: Luke Oberhagemann, Maik Billing & Markus Drüke (Spitfire update)

Output Data

Experiments: (*) obsclim_1901soc_1901co2, obsclim_2015soc_1901co2, obsclim_nat_default, obsclim_2015soc_default, counterclim_histsoc_default, counterclim_histsoc_obsco2, obsclim_histsoc_1901co2, counterclim_nat_default, counterclim_1901soc_default, counterclim_2015soc_default, obsclim_1901soc_default, obsclim_histsoc_default, obsclim_histsoc_nofire
Climate Drivers: 20CRV3, 20CRV3-ERA5, 20CRV3-W5E5, GSWP3-W5E5
Date: 2024-01-23

Basic information

Model Version: 5.7.10-fire

Model Output License: CC0

Model License: AGPL-3.0 license

Simulation Round Specific Description: Please cite both reference papers listed below since there is no single paper describing the model version used in ISIMIP3a.

Resolution

Spatial aggregation: regular grid

Horizontal resolution: 0.5°x0.5°

Vertically resolved: Yes

Number of vertical layers: 5 hydrologically active soil layers

Additional spatial aggregation & resolution information: We use a mask prescribing the continental fraction of each cell. Use provided "cellarea" and "contfrac" outputs for aggregation over multiple cells.

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

Observed atmospheric climate data sets used: GSWP3-W5E5 (ISIMIP3a), 20CRv3, 20CRv3-ERA5, 20CRv3-W5E5

Emissions data sets used: Atmospheric composition (ISIMIP3a)

Socio-economic data sets used: National, gridded historical population

Land use data sets used: Historical, gridded land use

Other human influences data sets used: Reservoirs & dams, Nitrogen deposition (ISIMIP3), N-Fertilizer (ISIMIP3a), Water abstraction for domestic and industrial uses

Other data sets used: Lightning, Drainage direction map for river routing

Additional input data sets: Lake area fraction based on GLWD, modified version of GGCMI phase 3 crop calendar, CRU land-sea mask (corresponds to ISIMIP landseamask_water-global except for 1 cell), continental fraction based on GADM, soil data based on HWSD

Climate variables: huss, sfcWind, tasmax, tas, tasmin, rsds, pr

Additional information about input variables: long wave net radiation calculated from long wave downwelling radiation and mean temperature

Exceptions to Protocol

Exceptions: Landuse input provided by ISIMIP was extended further back in time for model spinup in "histsoc" experiments to avoid artefacts of long-running constant landuse. "1901soc" and "2015oc" experiments used constant landuse also for spinup as prescribed by protocol.

Spin-up

Was a spin-up performed?: Yes

Spin-up design: First spinup without any human forcing for 3500 years followed by transitional run of 400 years with human forcing (either constant (1901soc, 2015soc), or transient (histsoc) or no human forcing (nat)). No-fire sensitivity experiment also does not use fire during spinup and transitional run.

Natural Vegetation

Natural vegetation partition: Dynamic vegetation composition for natural vegetation

Natural vegetation dynamics: Bioclimatic limits determine whether PFTs can establish. Established PFTs compete for light, water and nitrogen and are also affected by disturbance, e.g. fire.

Soil layers: From top to bottom: 20 cm, 30 cm, 50 cm, 100 cm, 100 cm.

Management & Adaptation Measures

Management: Prescribed (constant) sowing dates and prescribed PHU requirements (transient over time) for annual crops. N fertilizer application according to ISIMIP input. Irrigation possible on irrigated areas according to landuse input and based on dynamically calculated irrigation requirements and water availability. Effects of tillage on croplands included in simulations. Prescribed constant livestock density on pastures. Note: Landuse fractions in ISIMIP input refer to the grid area and have been rescaled based on our continental area fraction mask.

Extreme Events & Disturbances

Key challenges: No effects of pests or water logging. Fire disturbance simulated on natural vegetation and pastures. No fires on cropland. Frost damage possible for annual crops.

Key model processes

Dynamic vegetation: yes, bioclimatic limits and competition for light, water and nitrogen.

Nitrogen limitation: yes

Carbon-cycle benchmarking

Does your model reach a (near) steady state after spin up (characterized by nbp of < 0.2 pgc y-1)? (yes/no, provide number): yes, NBP averaged over last 50 years of nat. veg. spinup: -0.009 PgC/yr (20crv3), 0.015 PgC/yr (20crv3-era5), 0.011 PgC/yr (20crv3-w5e5), 0.039 PgC/yr (gswp3-w5e5)

What is your modeled nbp for the 1990-2000 decade? is it within 1.2 +/- 0.8 gtc/yr (1-sigma) of observed data from o2/n2 trends (keeling and manning 2014) for 1990-1999 (yes/no, provide number): NBP averaged over 1990-1999: -0.07 PgC/yr (20crv3), 0.31 PgC/yr (20crv3-era5), 0.65 PgC/yr (20crv3-w5e5), 0.51 PgC/yr (gswp3-w5e5)