Impact model: SWAP

SWAP is one of the 15 regional hydrology models following the ISIMIP2a protocol which form the base of simulations for the ISIMIP2a regional water sector outputs; for a full technical description of the ISIMIP2a Simulation Data from Water (regional) Sector, see this DOI link:

Water (regional)
Contact Person
  • Georgy Ayzel (, Water Problems Institute, Russian Academy of Sciences (RAS) (Russia)
  • Evgeny E. Kovalev (, Water Problems Institute, Russian Academy of Sciences (RAS) (Russia)
  • Olga Nasonova (, Institute of Water Problems of the Russian Academy of Sciences (Russia)

Information for the model SWAP is provided for the simulation rounds shown in the tabs below. Click on the appropriate tab to get the information for the simulation round you are interested in.

Output Data
Experiments: historical (Lena, Darling, MacKenzie, Mississippi, Amazon, Rhine, Tagus, Niger, Ganges, Yellow, Yangtze)
Climate Drivers: WATCH (WFD)
Date: 2017-02-20
Spatial Aggregation: regular grid
Spatial Resolution: 0.5°x0.5°
Temporal Resolution Of Input Data: Climate Variables: daily
Temporal Resolution Of Input Data: Soil: constant
Input data sets used
Observed Atmospheric Climate Data Sets Used: WATCH (WFD)
Climate Variables: tas, rlds, wind, rhs, rsds, ps, pr
Additional Input Data Sets: Vegetation parameters were taken or derived from ECOCLIMAP
Was A Spin-Up Performed?: Yes
Spin-Up Design: We started the simulations from 1July 1969 and the first year was simulated 4 times for spin-up (according to our experience it is enough to reach equilibrium by our model).
Natural Vegetation
Natural Vegetation Partition: We aggregated parameters taken from ECOCLIMAP for 0.5 deg grid cells
Management & Adaptation Measures
Management: no
Extreme Events & Disturbances
Key Challenges: Time step should be finer to reproduce high flow more accurately.
Technological Progress
Technological Progress: No.
Soil Layers: For water: the uppermost drying layer, rooting layer and a layer between the lower boundary of rooting zone and the upper impermeable layer. For energy: freezing and thawing zones.
Runoff Routing: Kinematic wave equation for water transfer within a grid cell and a linear routing scheme by Oki et al. 1999 for water transfer in a river channel.
Was The Model Calibrated?: True
Which Years Were Used For Calibration?: Varied depending on the data availability in different basins
Which Dataset Was Used For Calibration?: WFD
How Is Vegetation Represented?: Fixed monthly vegetation characteristics.
Potential Evapotranspiration: See papers
Snow Melt: Energy balance