Browsing by Autor "Claudia Canedo Rosso"

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Drought impact in the Bolivian Altiplano agriculture associated with the El Niño–Southern Oscillation using satellite imagery data
(Copernicus Publications, 2021) Claudia Canedo Rosso; Stefan Hochrainer‐Stigler; Georg Ch. Pflug; Bruno Condori; Ronny Berndtsson
Abstract. Drought is a major natural hazard in the Bolivian Altiplano that causes large agricultural losses. However, the drought effect on agriculture varies largely on a local scale due to diverse factors such as climatological and hydrological conditions, sensitivity of crop yield to water stress, and crop phenological stage among others. To improve the knowledge of drought impact on agriculture, this study aims to classify drought severity using vegetation and land surface temperature data, analyse the relationship between drought and climate anomalies, and examine the spatio-temporal variability of drought using vegetation and climate data. Empirical data for drought assessment purposes in this area are scarce and spatially unevenly distributed. Due to these limitations we used vegetation, land surface temperature (LST), precipitation derived from satellite imagery, and gridded air temperature data products. Initially, we tested the performance of satellite precipitation and gridded air temperature data on a local level. Then, the normalized difference vegetation index (NDVI) and LST were used to classify drought events associated with past El Niño–Southern Oscillation (ENSO) phases. It was found that the most severe drought events generally occur during a positive ENSO phase (El Niño years). In addition, we found that a decrease in vegetation is mainly driven by low precipitation and high temperature, and we identified areas where agricultural losses will be most pronounced under such conditions. The results show that droughts can be monitored using satellite imagery data when ground data are scarce or of poor data quality. The results can be especially beneficial for emergency response operations and for enabling a proactive approach to disaster risk management against droughts.
Drought risk in the Bolivian Altiplano associated with El NiñoSouthern Oscillation using satellite imagery data
(2019) Claudia Canedo Rosso; Stefan Hochrainer‐Stigler; Georg Ch. Pflug; Bruno Condori; Ronny Berndtsson
Abstract. Drought is a major natural hazard in the Bolivian Altiplano that causes large losses to farmers, especially during positive ENSO phases. However, empirical data for drought risk estimation purposes are scarce and spatially uneven distributed. Due to these limitations, similar to many other regions in the world, we tested the performance of satellite imagery data for providing precipitation and temperature data. The results show that droughts can be better predicted using a combination of satellite imagery and ground-based available data. Consequently, the satellite climate data were associated with the Normalized Difference Vegetation Index (NDVI) in order to evaluate the crop production variability. Moreover, NDVI was used to target specific drought hotspot regions. Furthermore, during positive ENSO phase (El Niño years), a significant decrease in crop yields can be expected and we indicate areas where losses will be most pronounced. The results can be used for emergency response operations and enable a pro-active approach to disaster risk management against droughts. This includes economic-related and risk reduction strategies such as insurance and irrigation.
Early warning and drought risk assessment for the Bolivian Altiplano agriculture using high resolution satellite imagery data
(2018) Claudia Canedo Rosso; Stefan Hochrainer‐Stigler; Georg Ch. Pflug; Bruno Condori; Ronny Berndtsson
Abstract. Implementation of agriculturally related early warning systems is fundamental for the management of droughts. Additionally, risk-based approaches are superior in tackling future drought hazards. Due to data-scarcity in many regions, high resolution satellite imagery data are becoming widely used. Focusing on ENSO warm and cold phases, we employ a risk-based approach for drought assessment in the Bolivian Altiplano using satellite imagery data and application of an early warning system. We use a newly established high resolution satellite dataset and test its accuracy as well as performance to similar (but with less resolution) datasets available for the Bolivian Altiplano. It is shown that during the El Niño years (warm ENSO phase), the result is great difference in risk and crop yield. Furthermore, the Normalized Difference Vegetation Index (NDVI) can be used to target specific hot spots on a very local scale. As a consequence, ENSO early warning forecasts as well as possible magnitudes of crop deficits could be established by the government, including an identification of possible hotspots during the growing season. Our approach therefore should not only help in determining the magnitude of assistance needed for farmers on the local scale but also enable a pro-active approach to disaster risk management against droughts that can include economic-related instruments such as insurance as well as risk reduction instruments such as irrigation.
Evaluación del requerimiento de agua en zonas productoras de quinua bajo condiciones de cambio climático
(2015) Claudia Canedo Rosso; Magali García Cárdenas
El objetivo del presente trabajo de investigación fue analizar la relación entre la probabilidad de las precipitaciones y el requerimiento de riego deficitario de la quinua proyectado a condiciones futuras de cambio climático en el Altiplano boliviano. Este trabajo de investigación comprende tres partes fundamentales, el análisis de la frecuencia de precipitaciones en el Altiplano, la proyección de las condiciones futuras obtenidas por la reducción de escala (downscaling) estadístico de un modelo de circulación general (MCG) y el análisis del requerimiento de agua de la quinua con riego deficitario. Estos tres ejes posibilitaron la identificación de medidas de adaptación del cultivo de la quinua bajo un posible impacto de cambio climático. El análisis de frecuencias de las precipitaciones en el Altiplano de Bolivia fue realizado siguiendo la metodología del análisis regional de frecuencias basadas en L-momentos propuesta por Hosking y Wallis (1997). Se determinaron las precipitaciones anuales para un año seco (25% de probabilidad de no excedencia de la precipitación media anual (PMA)), normal (50%) y húmedo (75%) para cada región identificada en el Altiplano a partir de dos criterios de homogeneidad, los cuales son la PMA e índice de estacionalidad de las precipitaciones. Posteriormente se realizó el análisis de las proyecciones de temperatura y precipitación de cuatro localidades del Altiplano central (Patacamaya y Oruro) y Altiplano sur (Río Mulatos y Uyuni), a través de una reducción de escala estadístico bajo los límites del Modelo de Circulación General ECHAM5.0 con las condiciones previstas por el IPCC (2007) para el escenario A2. Finalmente se determinó el requerimiento de agua del cultivo de la quinua para el presente y para las condiciones proyectadas en las décadas 2020-2029 y 2046-2055, mediante la comparación de los rendimientos del cultivo obtenidos a secano y bajo riego deficitario. Los resultados muestran que frecuencias de las precipitaciones presentan diferencias en la precipitación del Altiplano norte, central y sur de Bolivia. Para una probabilidad de no excedencia de 50% (año normal) el Altiplano norte y central presenta una precipitación media entre 404 a 800 mm/año, en el Altiplano sur entre 156 a 400 mm/año. Esto muestra la aridez característica del Altiplano sur. La temperatura mínima y máxima se incrementará 2 a 3 °C en las cuatro localidades. Los cambios en la lluvia son menores, las precipitaciones proyectadas para la década 2020-2029 reducirán entre un 1 a 4% y para la década 2046-2055 las precipitaciones anuales reducirán entre un 1 a 8%. Se muestran menores cambios para el Altiplano central. La aplicación de riego deficitario muestra un incremento en los rendimientos del cultivo de la quinua.
Precipitation variability and its relation to climate anomalies in the Bolivian Altiplano
(Wiley, 2018) Claudia Canedo Rosso; Cíntia Bertacchi Uvo; Ronny Berndtsson
Precipitation variability over the Bolivian Altiplano is strongly affected by local climate and temporal variation of large‐scale atmospheric flow. Precipitation is the main water source for drinking water and agricultural production. For this reason, a better understanding of precipitation variability and its relation with climate phenomena can provide important information for forecasting of droughts and floods, disaster risk reduction, and improvement of water management. We present results of an analysis of the austral summer precipitation variability at six locations in the Bolivian Altiplano and connections to climate variability. For this purpose, the variability of the summer precipitation was related to El Niño–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), Antarctic Meridional Mode (AMM), and Atlantic Multidecadal Oscillation (AMO). A statistically significant correlation between climate indices and precipitation was found in various spectral frequencies and power. The variability of the summer precipitation was associated with the climate indices using a band‐pass filter, representing the signal at a particular period of time. For the ENSO, band‐pass filtering was applied for Niño3.4 and Niño3 at band ~2–7 years, for NAO band ~5–8 years, and for AMM band ~10–13 years. The variability of summer precipitation was related to all studied climate modes by negative relationships. The physical explanation for this is first the dry air transported from the Pacific Ocean to the Altiplano during El Niño events. Second, NAO and ENSO are dynamically linked through teleconnections. Third, the intertropical convergence zone (ITCZ) shifts are northwards during the warm phases of AMM. These physical mechanisms lead to a reduced austral summer precipitation associated with positive phases of the ENSO, NAO, and AMM. The results can be used to better forecast precipitation in the Bolivian Altiplano and provide support for the development of policies to improve climate resilience and risk management of water supply.
Role of Hydrological Studies for the Development of the TDPS System
(Multidisciplinary Digital Publishing Institute, 2016) Claudia Canedo Rosso; Ramiro Pillco Zolá; Ronny Berndtsson
The South American Altiplano in the Andes is, aside from Tibet, the most extensive high plateau on Earth. This semiarid area represents important water resources storages, including the Lakes Titicaca and Poopó located in the northern and central Altiplano, respectively. The two lake basins and the southern saltpans constitute a large watershed, called the Lake Titicaca, Desaguadero River, Lake Poopó, and Coipasa Salt Flat System (TDPS hydrologic system). The Altiplano climate, topography, and location determine the TDPS hydrologic functioning. Scarce data and high spatial variability represent challenges to correctly simulate the TDPS water budget. Consequently, there is an important need to improve the understanding of the water resources in current and future climate over the area. The paper provides a comprehensive state-of-the-art regarding current knowledge of the TDPS hydro-socioeconomic system and summarizes the data needs to improve the current hydrological understanding.