High-Resolution Synoptically conditioned Weather Generator (HiReS-WG)

The High-Resolution Synoptically conditioned Weather Generator (HiReS-WG) is a stochastic rainfall model that generates rain
fields with a substantial proportion of convective features (Peleg and Morin, 2014). The rain fields are generated based on the empirical distributions of the rainfall characteristics subjected to the classified wet synoptic system.
The model is composed of four modules: (1) synoptic generator; (2) motion vector generator, i.e. advecion component; (3) convective rain cell generator; and (4) low-intensity rainfall generator. The model has been tested for generating high-resolution rainfall fields for present and future climate for hydrological applications (Peleg at al., 2015), and can be used for other ecological, agricultural and geomorphological applications. HiReS-WG is parsimonious in computational demands and is coded in Matlab environment.

Schematic description of the HiReS-WG modules. (1) The synoptic generator produces 6 h periods of wet/dry conditions and synoptic types (S, T), where the blue regions mark the duration of the rain event within the 6 h period. (2) The motion-vector generator produces, for periods of wet events, direction, and velocity values at 5 min time steps (represented by the arrows’ direction and length). (3) and (4) The convective rain cell and low-intensity rainfall generators produce, for periods of wet events, rain fields at 5 min time steps with
a spatial resolution of 0.5 km by 0.5 km. The rain fields follow the statistics of the relevant synoptic type and are advected and change along
the corresponding motion vector.

An example of the convective-cell generator product.


Peleg, N., and E. Morin (2014), Stochastic convective rain-field simulation using a high-resolution synoptically conditioned weather generator (HiReS-WG), Water Resour. Res., 50, 2124–2139, doi:10.1002/2013WR014836.

Peleg, N., Shamir, E., Georgakakos, KP., Morin, E., (2015), A framework for assessing hydrological regime sensitivity to climate change in a convective rainfall environment: A case study of two medium-sized eastern Mediterranean catchments, Israel. Hydrol. Earth Syst. Sci., 19, 567–581, doi:10.5194/hess-19-567-2015.