Browsing by Author "Molina-Carpio, Jorge"
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Item Open Access Comparative analysis of climate change impacts on meteorological, hydrological, and agricultural droughts in the lake Titicaca basin(MDPI, 2021-01-13) Zubieta Barragán, Ricardo; Molina-Carpio, Jorge; Laqui, Wilber; Sulca Jota, Juan Carlos; Ilbay, MercyThe impact of climate change on droughts in the Lake Titicaca, Desaguadero River, and Lake Poopo basins (TDPS system) within the Altiplano region was evaluated by comparing projected 2034–2064 and observed 1984–2014 hydroclimate time series. The study used bias-corrected monthly climate projections from the fifth phase of the Coupled Model Intercomparison Project (CMIP5), under the Representative Concentration Pathway 8.5 (RCP8.5) emission scenarios. Meteorological, agricultural, and hydrological droughts were analyzed from the standardized precipitation, standardized soil moisture, and standardized runoff indices, respectively, the latter two estimated from a hydrological model. Under scenarios of mean temperature increases up to 3 °C and spatially diverse precipitation changes, our results indicate that meteorological, agricultural, and hydrological droughts will become more intense, frequent, and prolonged in most of the TDPS. A significant increase in the frequency of short-term agricultural and hydrological droughts (duration of 1–2 months) is also projected. The expected decline in annual rainfall and the larger evapotranspiration increase in the southern TDPS combine to yield larger projected rises in the frequency and intensity of agricultural and hydrological droughts in this region.Item Open Access Decline of fine suspended sediments in the Madeira River Basin (2003–2017)(MDPI, 2019-03-12) Ayes Rivera, Irma; Armijos Cardenas, Elisa Natalia; Espinoza Villar, Raúl Arnaldo; Espinoza, Jhan Carlo; Molina-Carpio, Jorge; Max Ayala, José; Gutierrez Cori, Omar; Martinez, Jean-Michel; Filizola, NazianoThe Madeira River is the second largest Amazon tributary, contributing up to 50% of the Amazon River’s sediment load. The Madeira has significant hydropower potential, which has started to be used by the Madeira Hydroelectric Complex (MHC), with two large dams along the middle stretch of the river. In this study, fine suspended sediment concentration (FSC) data were assessed downstream of the MHC at the Porto Velho gauging station and at the outlet of each tributary (Beni and Mamoré Rivers, upstream from the MHC), from 2003 to 2017. When comparing the pre-MHC (2003–2008) and post-MHC (2015–2017) periods, a 36% decrease in FSC was observed in the Beni River during the peak months of sediment load (December–March). At Porto Velho, a reduction of 30% was found, which responds to the Upper Madeira Basin and hydroelectric regulation. Concerning water discharge, no significant change occurred, indicating that a lower peak FSC cannot be explained by changes in the peak discharge months. However, lower FSCs are associated with a downward break in the overall time series registered at the outlet of the major sediment supplier—the Beni River—during 2010.Item Restricted Hydroclimatology of the Upper Madeira River basin: spatio-temporal variability and trends(Taylor & Francis, 2017-01-17) Molina-Carpio, Jorge; Espinoza, Jhan Carlo; Vauchel, Philippe; Ronchail, Josyane; Gutierrez Caloir, Beatriz; Guyot, Jean-Loup; Noriega, LuisRising in the Andes, the Madeira River drains the southwestern part of the Amazon basin, which is characterized by high geographical, biological and climatic diversity. This study uses daily records to assess the spatio-temporal runoff variability in the Madeira sub-basins. Results show that inter-annual variability of both discharge and rainfall differs between Andean and lowland tributaries. High-flow discharge variability in the Andean tributaries and the Guaporé River is mostly related to sea surface temperature (SST) in the equatorial Pacific in austral summer, while tropical North Atlantic (TNA) SST modulates rainfall and discharge variability in the lowlands. There also is a downward trend in the low-flow discharge of the lowland tributaries which is not observed in the Andes. Because low-flow discharge values at most lowland stations are negatively related to the SST in the tropical North Atlantic, these trends could be explained by the warming of this ocean since the 1970s.Item Open Access Impactos del cambio climático en diferentes tipos de sequías en la cuenca del Titicaca(Instituto Geofísico del Perú, 2021-07) Zubieta Barragán, Ricardo; Molina-Carpio, Jorge; Laqui, Wilber; Sulca Jota, Juan Carlos; IIbay, MercyEl presente trabajo evalúa el impacto del cambio climático en la ocurrencia de sequías para las cuencas del Lago Titicaca, Río Desaguadero y Lago Poopo (Sistema TDPS). Para tal objetivo, se comparan los resultados de los modelos climáticos para el periodo 1984-2014 con los datos observados y se evalúan las proyecciones en el periodo 2034- 2064. El estudio utilizó proyecciones climáticas mensuales provenientes del proyecto CMIP5 bajo el escenario de emisión RCP8.5. Se corrigió el sesgo y se analizaron las sequías meteorológicas, agrícolas e hidrológicas a partir de los índices estandarizados de precipitación, humedad del suelo y escorrentía, respectivamente. La humedad del suelo y escorrentía fueron estimados a partir del modelo hidrológico GR2M. Ante el aumento de la temperatura regional media de hasta 3 °C y los cambios de intensidad, cantidad y patrón espacial de la precipitación, nuestros resultados indican que las sequías meteorológicas, agrícolas e hidrológicas serían más intensas, frecuentes y prolongadas en el sistema TDPS. También se proyecta un aumento en la frecuencia de sequías agrícolas e hidrológicas (duración de 1 a 2 meses). La disminución esperada en la precipitación anual y el mayor aumento de la evapotranspiración en la región sur (Bolivia) de la cuenca producirían aumentos proyectados más grandes que en la región norte (Perú).Item Open Access On the relationship between suspended sediment concentration, rainfall variability and groundwater: an empirical and probabilistic analysis for the Andean Beni River, Bolivia (2003–2016)(MDPI, 2019-11) Ayes Rivera, Irma; Callau Poduje, Ana Claudia; Molina-Carpio, Jorge; Ayala, José Max; Armijos Cardenas, Elisa Natalia; Espinoza-Villar, Raúl; Espinoza, Jhan Carlo; Gutierrez-Cori, Omar; Filizola, NazianoFluvial sediment dynamics plays a key role in the Amazonian environment, with most of the sediments originating in the Andes. The Madeira River, the second largest tributary of the Amazon River, contributes up to 50% of its sediment discharge to the Atlantic Ocean, most of it provided by the Andean part of the Madeira basin, in particular the Beni River. In this study, we assessed the rainfall (R)-surface suspended sediment concentration (SSSC) and discharge (Q)-SSSC relationship at the Rurrenabaque station (200 m a.s.l.) in the Beni Andean piedmont (Bolivia). We started by showing how the R and Q relationship varies throughout the hydrological year (September to August), describing a counter-clockwise hysteresis, and went on to evaluate the R–SSSC and Q–SSSC relationships. Although no marked hysteresis is observed in the first case, a clockwise hysteresis is described in the second. In spite of this, the rating curve normally used ( SSSC=aQb ) shows a satisfactory R² = 0.73 (p < 0.05). With regard to water discharge components, a linear function relates the direct surface flow Qs–SSSC, and a hysteresis is observed in the relationship between the base flow Qb and SSSC. A higher base flow index (Qb/Q) is related to lower SSSC and vice versa. This article highlights the role of base flow on sediment dynamics and provides a method to analyze it through a seasonal empirical model combining the influence of both Qb and Qs, which could be employed in other watersheds. A probabilistic method to examine the SSSC relationship with R and Q is also proposed.