Modelling snow accumulation and snowmelt runoff – present approaches and results

Michal Jeníček,Slávek Podzimek,Hana Beitlerová,Dana Kučerová,Hana Pevná,Martin Hasa

doi:10.14712/23361980.2015.13

Abstract

The aim of the article is to give a review of methods applied for modelling the snow accumulation and snowmelt and to give a description of main processes governing the runoff from the snowpack. The progress in the understanding of processes running in the snowpack is documented both by worldwide results presented in many studies and by the results achieved by the authors in the selected small experimental catchments in the Czech Republic. The research is focused on 1) measuring the snowpack and analysing its spatial and temporal distribution, 2) assessing the role of different physical-geographical factors on snow accumulation and melting, 3) testing methods for interpolation of measured point data into area, and 4) modelling the snow accumulation and snowmelt in the local and regional scale. The main findings of the research show various ways of behaviour of snowpack accumulated in the forest and open areas in experimental catchments and show the most suitable interpolation methods taking into account one or more independent variables (slope, aspect, altitude, vegetation) for calculating the dependent variable (snow water equivalent, snow depth). The presented results also confirm the known problems with applying temperature-index snowmelt model, mainly for modelling the situations when the air temperature fluctuates near zero and for modelling the diurnal fluctuation of the snowmelt runoff.

Highlights

The snow melting caused by higher temperature, accompanied with precipitation, is a frequent cause of floods in the Czech Republic
The most important initial condition for the flood forecast caused by snow melting is the snow layer status, mainly snow depth and snow water equivalent (SWE)
The effects of altitude and air temperature are significant for large areas that exhibit high variability in terms of elevation (Essery 2003; Jost et al 2007), while the effect of vegetation predominates locally, namely the presence of forests and open areas in the river basin (Jost et al 2009; Tanasienko et al 2009)

Summary

Introduction

The snow melting caused by higher temperature, accompanied with precipitation, is a frequent cause of floods in the Czech Republic. The most important initial condition for the flood forecast caused by snow melting is the snow layer status, mainly snow depth and snow water equivalent (SWE). Numerous studies indicate various effects of both natural and anthropogenic factors on runoff formation (Jost et al 2007; Váňová and Langhammer 2011) especially the role of the landscape and different land cover (forest, meadows, arable land). The majority of studies are focused on floods caused by liquid precipitation (Čurda et al 2011; Jeníček 2009) or they assess the runoff on a longterm scale (Özdogan 2011; Kliment et al 2011). Jeníček and Taufmannová (2010) has used the HEC-HMS model including the temperature-index snowmelt model for the runoff simulation from various vegetation covers (forest and open areas). The results indicate an applicability of temperature-index method for variant simulations of the rainfall-runoff process, especially for “rain-on-snow” events

Objectives

Methods

Findings

Discussion

Conclusion