Author(s): V. Moya Quiroga; A. Mano; Y. Asaoka; K. Udo; S. Kure; J. Mendoza
Linked Author(s): Saskia Marcellys Jimenez Mendoza
Keywords: Mass balance; Energy balance; Ablation; Snowfall; Equilibrium line altitude
Abstract: Precipitation is the most important water input to the land phase of the hydrological cycle. Precipitation may be liquid (rainfall), solid (snowfall) or mixed (rainfall and snowfall). The type of precipitation is important for water resources studies. The rainfall snowfall partition of precipitation is based on temperature. However, the estimation of temperature in mountainous regions is a challenging due, especially in scarce data areas. Usually temperature measurements from one station are extrapolated considering a given lapse rate. Such lapse rate may be an important source of uncertainty. Additionally, the temperature measurement devices have some systematic errors that may induce additional uncertainties to the snowfall estimation. Unfortunately, there are few studies considering the influence of such uncertainties when estimating snowfall. The present study estimates rainfall and snowfall at the Andean basins Condoriri and Huayna West considering the uncertainties due to systematic errors of the temperature measurements and the temperature lapse rate. Precipitation and temperature were measured by automatic weather stations installed in 2011. The present study considered data from the hydrological years 2011-2012 and 2012-2013. The total precipitation was separated into rainfall and snowfall considering the two temperature thresholds approach. The temperature measurement errors were estimated according to the specifications of the temperature sensor. The yearly snowfall is between 44.9 mm and 68.7 mm. The months with highest snowfall uncertainty are the summer months (between October and March). The constant lapse rates suggested for the study area either underestimate or overestimate the snowfall. The use of a variable lapse rate improves the snowfall estimation.
Year: 2014