Capabilities and limitations of detailed hillslope hydrological modelling

Topographical Controls on Hillslope‐Scale Hydrology Drive Shrub Distributions on the Seward Peninsula, Alaska

“…In particular, the observed spatial heterogeneity of shrubs across the Kougarok Hillslope was not captured in our simulation that artificially ignored topography (Figure 7a), indicating that landscape hydrology is a crucial factor affecting shrub expansion. Although topographic controls of hillslope hydrology in watersheds have been represented in hydrological models (Bronstert, 1999; Clark et al., 2009; Ji et al., 2015; Stieglitz et al., 1999; Xiao et al., 1996), most large‐scale land surface models use hydrologically disconnected grid cells (Hazenberg et al., 2016) and thus ignore landscape level heterogeneity in soil water content. These models are not able to capture landscape level heterogeneity in soil water content and nutrients, thus likely biasing their predictions of tundra shrub expansion.…”

The role of bedrock topography on subsurface storm flow

“…Indeed, it should be expected that that given the complexity of the subsurface topography, further variations in the localized patterns of the topographic index and patterns of saturation would be expected if higher resolution data were available. Given this complexity of the hydrological responses for what was chosen as a relatively planar hillslope area, identification of a simplified nor even relatively complex physically based hydrological model structure (such as that of Bronstert [1999]) would be problematic. The question then is how important is this detail in the representation of responses at the catchment scale and whether general patterns that will not reflect all the local detail will suffice [e.g., Woods et al , 1997].…”

Formation of runoff at the hillslope scale during intense precipitation

“…Some of them observed high contributions of water to storm runoff transferred by Table 1. pipes, especially in forested areas. Investigations focusing on the infiltration process confirmed the relevance of the matrix being bypassed via macropores (Bronstert, 1999;Jones and Connelly, 2002). Tracer experiments performed by Bouma (1991); Ghodrati and Jury (1990), Flury et al (1994), and Weiler and Naef (2003) showed that rapid flow can occur along macropores.…”