Assessing multidecadal runoff (1970–2010) using regional hydrological modelling under data and water scarcity conditions in Peruvian Pacific catchment

• Autores: Rau, P., Bourrel, L., Labat, D., Ruelland, D., Frappart, F., Lavado-Casimiro, W., Dewitte, v, Felipe-Obando, Oscar
• Formato: artículo
• Fecha de Publicación: 2019
• Institución: Servicio Nacional de Meteorología e Hidrología del Perú
• Repositorio: SENAMHI-Institucional
• Lenguaje: inglés
• OAI Identifier: oai:repositorio.senamhi.gob.pe:20.500.12542/41
• Enlace del recurso: http://repositorio.senamhi.gob.pe/handle/20.500.12542/41; https://doi.org/ 10.1002/hyp.13318; https://hdl.handle.net/20.500.12542/41
• Nivel de acceso: acceso abierto
• Materia: Dta and water scarcity; GR1A; GR2M; hydrological modelling; Peru; Regional runoff; Catchment; Climate models; Water; https://purl.org/pe-repo/ocde/ford#1.05.11; conservacion y recuperacion de cuencas hidrograficas - Agua

In a context of water scarcity in Peruvian Pacific catchments as a crucial issue for Peru, added to the paucity of data availability, we propose a methodology that provides new perspectives for freshwater availability estimation as a base reference for unimpaired conditions. Under those considerations, a regional discharge of 709 m3/s to the Pacific Ocean is estimated with a significant increasing trend of about 43 m3/s per decade over the 1970–2010 period. To represent the multidecadal behaviour of freshwater runoff along the region, a regional runoff analysis is proposed based on hydrological modelling at annual and monthly time step for unimpaired conditions over the whole 1970–2010 period. Differential Split-Sample Tests are used to assess the hydrological modelling robustness of the GR1A and GR2M conceptual lumped models, showing a satisfactory transposability from dry to wet years inside the thresholds defined for Nash–Sutcliffe and bias criteria. This allowed relating physical catchment characteristics with calibrated and validated model parameters, thus offering a regional perspective for dryland conditions in the study area (e.g., the anticlockwise hysteresis relationship found for seasonal precipitation–runoff relationship) as well as the impacts of climate variability and catchment characteristics.