An Intercomparison of Three Snow Schemes of Varying Complexity Coupled to the Same Land Surface Model: Local-Scale Evaluation at an Alpine Site

Abstract

The Interactions between Soil, Biosphere, and Atmosphere land surface scheme is currently used coupled both to atmospheric models and to a distributed hydrological model. There are two snow-scheme options available for hydrological modeling: the baseline force-restore approach, which uses a composite snow-soil-vegetation energy budget and a single snow layer; and a multilayer detailed internal-process snow model. Only the forcerestore method is routinely used in atmospheric modeling applications. Recent studies have shown that hydrological simulations for mountainous catchments within the Rhone basin, France, are significantly improved using the detailed snow scheme. The main drawback is that the scheme is computationally expensive, and it is not currently feasible for routine application in atmospheric models. For these reasons, a third new intermediatecomplexity scheme has been developed that includes certain key physical processes from the complex model for improved snowpack realism and hydrological depiction while attemping to keep computational requirements similar to those of the simple default scheme. In the current study, the new scheme is described, evaluated, and compared with the results from the two other schemes at a local scale at an alpine site located within the Rhone basin for two contrasting (weather) years. All schemes are able to model the basic features of the snow cover with similar errors averaged over the 2-yr period; however, there are important differences on shorter timescales. When compared with the more complex scheme, it was found that differing surface energy budget parameterizations (turbulent transfer, albedo) were the cause for the largest differences in total snowpack snow water equivalent (SWE) simulated by the models. When compared with the simple scheme, the ability for the intermediate model to simulate snow ripening resulted in the largest differences in simulated SWE and snow temperature during melt and runoff.

Introducing Hysteresis in Snow Depletion Curves to Improve the Water Budget of a Land Surface Model in an Alpine Catchment

“…The multilayer, physically based snow scheme included in the CLSM (Lynch-Stieglitz 1994)i so fi n t e r m e d i a t e complexity according to Boone and Etchevers's (2001) classification of snow schemes and has shown good performance in different studies (Stieglitz et al 2001;Gascoin et al 2009b;Koster et al 2010). The snow model vertically discretizes the snowpack into three layers, and each of them is characterized by its heat content, SWE, and snow depth (Lynch-Stieglitz 1994;Stieglitz et al 2001;D ery et al 2004).…”

The interactions between soil–biosphere–atmosphere (ISBA) land surface model multi-energy balance (MEB) option in SURFEXv8 – Part 2: Introduction of a litter formulation and model evaluation for local-scale forest sites

“…It is used for a suit of surface schemes in either offline or coupled mode with an atmospheric model and/or a hydrological model. ISBA has benefited from continuous improvements since its first version (Noilhan and Planton, 1989), in particular for the carbon cycle (Calvet et al, 1998;Gibelin et al, 2006), soil mass and heat transfer (Boone et al, 1999;Decharme et al, 2011), snowpack processes (Boone and Etchevers, 2001;Decharme et al, 2016), sub-grid hydrology (Decharme and Douville, 2006) and radiative transfer through the canopy .…”

Combining livestock production information in a process-based vegetation model to reconstruct the history of grassland management

“…The single-bucket snowpack scheme (Chalita and Le Treut, 1994) in the current version of ORCHIDEE-GM may not represent the snow processes sufficiently accurately. The mechanistic intermediatecomplexity snow scheme (ISBA-ES; Boone and Etchevers, 2001) implemented into ORCHIDEE-ES may improve the model performance in simulating grassland productivity.…”