Effect of modelling scale on the assessment of climate change impact on river runoff

Abstract

The effect of using two distributed hydrological models with different degrees of spatial aggregation on the assessment of climate change impact on river runoff was investigated. Analyses were conducted in the Narew River basin situated in northeast Poland using a global hydrological model (WaterGAP) and a catchment-scale hydrological model (SWAT). Climate change was represented in both models by projected changes in monthly temperature and precipitation between the period 2040-2069 and the baseline period, resulting from two general circulation models: IPSL-CM4 and MIROC3.2, both coupled with the SRES A2 emissions scenario. The degree of consistency between the global and the catchment model was very high for mean annual runoff, and medium for indicators of high and low runoff. It was observed that SWAT generally suggests changes of larger magnitude than WaterGAP for both climate models, but SWAT and WaterGAP were consistent as regards the direction of change in monthly runoff. The results indicate that a global model can be used in Central and Eastern European lowlands to identify hot-spots where a catchment-scale model should be applied to evaluate, e.g. the effectiveness of management options.

Assessment of climate change impacts on water quantity and quality of the multi-river Vistula Lagoon catchment

“…Some regional trends can even be opposite to the overall trend for large areas (Arheimer et al 2012), and some local effects can be masked by the large-scale aggregation (Piniewski et al 2013a). They also noticed that the difference between the results achieved with one hydrological model under two or more different climate scenarios is sometimes larger than the difference between the results of different hydrological models or different management measures achieved by using one climate scenario (Arheimer et al 2012, Piniewski et al 2013a, 2013b. Hence, a large uncertainty is related to climate models and downscaling methods, which can be partly compensated for by applying an ensemble of different climate scenarios (Tebaldi and Knutti 2007, Huard 2011, Arheimer et al 2012.…”

Investigating the uncertainty and transferability of parameters in SWAT model under climate change

“…Physically-based hydrological models are more suitable for simulations of basin response to a changing climate than empirical or conceptual models which rely more heavily on parameters calibration (Ragettli and Pellicciotti 2012). However, problems with a priori estimation of model parameters make physically-based hydrological models difficult to apply, while conceptual models are often argued to be a more practical alternative (Piniewski et al 2013). Parameters employed in hydrological models (e.g.…”

“…However, it is often assumed that spatially explicit distributed hydrological models are more suited to predict the effects of changing environmental conditions (Beven and Binley 1992). The use of semi-distributed and distributed hydrological models in climate change impact analysis is increasing all the time (Maurer et al 2010, Piniewski et al 2013. The Soil and Water Assessment Tool (SWAT) model is used in this study.…”

From global circulation to local flood loss: Coupling models across the scales

“…Fowler et al, 2007;Kundzewicz & Stakhiv, 2010;Teng et al, 2012;Wilby, 2010). More recent studies focused on specific methodological problems in this procedure, namely on scale effects (Piniewski et al, 2013), rainfall statistics (Langousis et al, 2016), and hydro-meteorological extremes (Madsen et al, 2014;Tofiq & Guven, 2014;Sunyer et al, 2015). The results of these studies have confirmed the applicability of linking GCMs to hydrological models via RCMs.…”