Examensarbete vid Institutionen för geovetenskaper Usability of Standard Monitored Rainfall-Runoff Data in Panama, ISSN 1650-6553 Nr 242 Juan Diaz River Basin José Eduardo Reynolds Puga Usability of Standard Monitored Water resources demand and natural disasters related to hydro meteorological events have increased the interest in hydrological studies in Panama. Runoff estimations are Rainfall-Runoff Data in Panama, important for effective water resources management in any catchment, but the limited quantity and quality of the available hydrological and meteorological data in Juan Diaz River Basin Panama make it hard for researchers to come to conclusive statements that can help in good planning. This issue has to be addressed, but meanwhile, the challenge is to try to understand the hydrological processes occurring in any catchment with the available data. The relationship between rainfall and runoff in the Juan Diaz River basin is not well understood and its fast response due to high rainfall intensities in the area is a concern in the community and authorities. The meteorological and hydrological data in the Juan Diaz River basin are also limited. The main objective of this thesis was José Eduardo Reynolds Puga to establish how well the Juan Diaz River basin can be hydrologically represented by records of the available instrumentation. This was performed with a hydrological, WASMOD, and a statistical model, linear multiple regression. Both models simulated daily and monthly runoff for a period of 21 years. For the long term water balance, a graph showing discharge against rainfall data was plotted in the yearly scale to establish a relationship between the two variables. Precipitation records from an active meteorological station, which was the closest to the basin from the ones with available records, were used in this study to estimate the areal mean precipitation of the basin, since nowadays there are no active meteorological stations within the basin. It was not possible to represent the Juan Diaz River basin well with the two models in the daily and monthly resolution. Uncertainties in the precipitation input and in the discharge output data were considered to be the reasons for the poor simulations. That said, it can be stated that the available instrumentation at this point is not sufficient for modeling. In the long term water balance, the instrumentation can be used for water estimations, but care has to be taken if this approach is used since the limited quantity of data in this scale were scattered around the predictions. Efforts have to be made to encourage decision makers to increase the available instrumentation in the Juan Diaz River basin, in order to make accurate simulations or forecasting that will better support water resources management. Uppsala universitet, Institutionen för geovetenskaper Examensarbete D, 15 hp i Hydrologi ISSN 1650-6553 Nr 242 Tryckt hos Institutionen för geovetenskaper, Geotryckeriet, Uppsala universitet, Uppsala, 2012. Examensarbete vid Institutionen för geovetenskaper ISSN 1650-6553 Nr 242 Usability of Standard Monitored Rainfall-Runoff Data in Panama, Juan Diaz River Basin José Eduardo Reynolds Puga Copyright © José Eduardo Reynolds Puga och Institutinen för geovetenskaper, Luft‐, vatten –och landskapslära, Uppsala Universitet. Tryckt hos Institutionen för geovetenskaper, Geotryckeriet, Uppsala universitet, Uppsala, 2012 ABSTRACT USABILITY OF STANDARD MONITORED RAINFALL‐RUNOFF DATA IN PANAMA, JUAN DIAZ RIVER BASIN. Reynolds, J., Department of Earth Science, Uppsala University, Villavägen 16, SE−752 36, Uppsala, Sweden. Water resources demand and natural disasters related to hydro meteorological events have increased the interest in hydrological studies in Panama. Runoff estimations are important for effective water resources management in any catchment, but the limited quantity and quality of the available hydrological and meteorological data in Panama make it hard for researchers to come to conclusive statements that can help in good planning. This issue has to be addressed, but meanwhile, the challenge is to try to understand the hydrological processes occurring in any catchment with the available data. The relationship between rainfall and runoff in the Juan Diaz River basin is not well understood and its fast response due to high rainfall intensities in the area is a concern in the community and authorities. The meteorological and hydrological data in the Juan Diaz River basin are also limited. The main objective of this thesis was to establish how well the Juan Diaz River basin can be hydrologically represented by records of the available instrumentation. This was performed with a hydrological, WASMOD, and a statistical model, linear multiple regression. Both models simulated daily and monthly runoff for a period of 21 years. For the long term water balance, a graph showing discharge against rainfall data was plotted in the yearly scale to establish a relationship between the two variables. Precipitation records from an active meteorological station, which was the closest to the basin from the ones with available records, were used in this study to estimate the areal mean precipitation of the basin, since nowadays there are no active meteorological stations within the basin. It was not possible to represent the Juan Diaz River basin well with the two models in the daily and monthly resolution. Uncertainties in the precipitation input and in the discharge output data were considered to be the reasons for the poor simulations. That said, it can be stated that the available instrumentation at this point is not sufficient for modeling. In the long term water balance, the instrumentation can be used for water estimations, but care has to be taken if this approach is used since the limited quantity of data in this scale were scattered around the predictions. Efforts have to be made to encourage decision makers to increase the available instrumentation in the Juan Diaz River basin, in order to make accurate simulations or forecasting that will better support water resources management. Keywords: Juan Diaz, WASMOD, Linear Multiple Regression, Available Instrumentation RESUMEN USABILIDAD DE REGISTROS TÍPICOS DE LLUVIA‐ESCORRENTÍA MONITOREADOS EN PANAMÁ, CUENCA DEL RÍO JUAN DÍAZ Reynolds, J., Departamento de Ciencias de las Tierra, Universidad de Uppsala, Villavägen 16, SE−752 36, Uppsala, Suecia. La demanda de recursos hídricos y la ocurrencia de desastres naturales relacionados con eventos hidro‐meteorologicos han incrementado el interés de estudios hidrológicos en Panamá. Estimaciones de escorrentía son importantes para el manejo efectivo de los recursos hídricos en cualquier cuenca, pero la calidad y cantidad limitada de registros hidrológicos y meteorológicos en Panamá hacen difícil a los investigadores llegar a conclusiones contundentes que puedan ayudar a una buena planificación. Este problema debe ser abordado, pero entretanto, el reto es tratar de entender los procesos hidrológicos que ocurren en las cuencas con los registros disponibles. La relación lluvia‐escorrentía en la lcuenca de Río Juan Díaz no se entiende completamente y su rápida respuesta debido a las lluvias de alta intensidad en el área es una preocupación en la comunidad y en las autoridades. Los registros meteorológicos e hidrológicos en la cuenca del Río Juan Díaz son limitados. El objetivo principal de esta tesis fue establecer que tan bien se podía representar hidrológicamente la cuenca del Río Juan Díaz con los registros disponibles de la instrumentación existente hoy en día en la misma. Esto se realizo con un modelo hidrológico, WASMOD, y con un modelo estadístico, regresión lineal múltiple. Ambos modelos simularon escorrentía diaria y mensual por un período de 21 años. Para el balance hídrico a largo plazo, se graficaron en la escala anual los datos de caudal contra los datos de precipitación para establecer una relación entre ambas variables. Registros de precipitación de una estación meteorológica activa, la cual era la más próxima a la cuenca de las estaciones con registros disponibles, fueron utilizados en este estudio para estimar la precipitación promedio areal de la cuenca, dado que hoy en día no hay ninguna estación meteorológica activa dentro de la misma. En la escala diaria y mensual, no fue posible representar bien la cuenca del Río Juan Díaz con los dos métodos seleccionados. Incertidumbres en los datos de entrada y salida fueron consideradas las razones de las pobres simulaciones. Dicho lo anterior, se puede concluir que la instrumentación existente en la cuenca hoy en día no es suficiente para su modelación hidrológica. En el balance hídrico a largo plazo, la instrumentación existente podría usarse pero cuidado debe tenerse si esta aproximación es utilizada ya que la cantidad limitada de datos en esta escala estaba dispersa alrededor de las predicciones. Esfuerzos tienen que hacerse para alentar a los tomadores de decisiones en Panamá para aumentar la instrumentación existente en la cuenca del Río Juan Díaz, para así poder hacer la misma posible para predicciones que servirán para una mejor planificación de sus recursos. Palabras Claves: Juan Díaz, WASMOD, Regresión Lineal Múltiple, Instrumentación Existente. REFERAT ANVÄNDBARHET AV TILLGÄNGLIGA ÖVERVAKNINGSDATA FÖR NEDERBÖRD OCH VATTENFÖRING I JUAN DIAZ‐FLODENS AVRINNINGSOMRÅDE, PANAMA Reynolds, J., Institutionen för geovetenskaper, Uppsala Universitet, Villavägen 16, 752 36 Uppsala Behovet av vattenresurser och den höga frekvensen