Correction of Precipitation Records through Inverse Modeling in Watersheds of South-Central Chile

Abstract

Precipitation is the main input in the water balance of watersheds; therefore, correct estimates are necessary for water resources management and decision making. In south-central Chile there is a low density of precipitation gauges (~1 station/675 km2), most of which are located in low-altitude areas. The spatial distribution of precipitation is, therefore, not properly recorded. In this study an inverse modeling approach is used to estimate the extent to which precipitation amounts must be corrected. Using a lumped water balance model, a factor for correcting precipitation data is calculated for 41 watersheds located in south-central Chile. Then, based on a geo-statistical interpolation, a map for correcting the precipitation amounts is proposed and a validation of these corrections is achieved. The results show that in gently sloping areas, the precipitation records are more representative than in steep mountain areas. In addition, the higher the mountains, the less representative the precipitation records become.

High-Resolution Precipitation Gridded Dataset on the South-Central Zone (34° S–41° S) of Chile

“…Thus, these high-resolution datasets are inadequate to study large areas and/or the whole country. Moreover, the insufficient spatial distribution of the pluviometric network (Muñoz et al, 2018) precludes real hydro-climatic impact under current environmental conditions.…”

Identifying a Suitable Model for Low-Flow Simulation in Watersheds of South-Central Chile: A Study Based on a Sensitivity Analysis

“…Table 2 presents the calibration parameter ranges defined in accord with the conceptual representation of each and experience acquired in a prior study on Chilean watersheds [9]. Considering that at the Andes mountain range there was a low density of rain gauges because most were located in low-altitude areas, consequently, the spatial distribution of precipitation was not properly recorded [36]. Thus, a precipitation adjustment parameter (parameter A) was included to correct the underestimation of precipitation due to the orographic effect in the studied watersheds.…”

An Adaptive Basin Management Rule to Improve Water Allocation Resilience under Climate Variability and Change—A Case Study in the Laja Lake Basin in Southern Chile

“…Most of the rain gauge and temperature stations are located in low-and mid-altitude areas (below 600 m.a.s.l. ), and thus the orographic effect and temperature gradient are not adequately measured [49]. To correct the model input variables and ensure the closure of the long-term mass balance, the use of such factors is deemed an appropriate option.…”

“…To correct the model input variables and ensure the closure of the long-term mass balance, the use of such factors is deemed an appropriate option. Some examples of the application of this method can be found in [49][50][51].…”