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Publication 700,000 years of tropical Andean glaciation(2022-07-14)Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial–interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores1; these interhemispheric connections may have existed during previous glacial cycles. - Some of the metrics are blocked by yourconsent settings
Publication A future of extreme precipitation and droughts in the Peruvian Andes(2023-12-01)Runoff from glacierised Andean river basins is essential for sustaining the livelihoods of millions of people. By running a high-resolution climate model over the two most glacierised regions of Peru we unravel past climatic trends in precipitation and temperature. Future changes are determined from an ensemble of statistically downscaled global climate models. Projections under the high emissions scenario suggest substantial increases in temperature of 3.6 °C and 4.1 °C in the two regions, accompanied by a 12% precipitation increase by the late 21st century. Crucially, significant increases in precipitation extremes (around 75% for total precipitation on very wet days) occur together with an intensification of meteorological droughts caused by increased evapotranspiration. Despite higher precipitation, glacier mass losses are enhanced under both the highest emission and stabilization emission scenarios. Our modelling provides a new projection of combined and contrasting risks, in a region already experiencing rapid environmental change. - Some of the metrics are blocked by yourconsent settings
Publication A new GLOF inventory for the Peruvian and Bolivian(2019-04)Abordar la cuestión de si las inundaciones repentinas de los lagos glaciares (GLOF) están cambiando en frecuencia y magnitud en los tiempos modernos requiere un contexto histórico, pero adolece de inventarios GLOF incompletos, especialmente en regiones montañosas remotas. Aquí, explotamos imágenes satelitales y aéreas multitemporales de alta resolución combinadas con datos documentales para identificar eventos GLOF en las Cordilleras glaciares de Perú y Bolivia, utilizando un conjunto de características geomórficas de diagnóstico. Se caracterizan y analizan más de 150 GLOF, superando con creces el número de eventos informados anteriormente. Proporcionamos estadísticas sobre la ubicación, magnitud, momento y características de estos eventos. Además, describimos varios casos en detalle y documentamos una amplia gama de cadenas de procesos asociadas con GLOF. - Some of the metrics are blocked by yourconsent settings
Publication A pre-Inca pot from underwater ruins discovered in an Andean lake provides a sedimentary record of marked hydrological change(2019-12-01)Pre-Hispanic artifacts and sacred architecture were recently discovered submerged in a large lake (Laguna Sibinacocha) in the Peruvian Andes. The underwater ruins indicate a dramatic shift in the region’s hydrology but the timing and triggers of this shift remain unknown. In a novel approach blending archaeology and paleoecology, we analyzed a sediment sequence from within one of the recovered artifacts, specifically a pot from the Late Intermediate Period (~1000–1400 CE). Radioisotopic dating of discrete sediment intervals sampled from the pot show a stratigraphically intact profile that preserves a history of change at this site. The pot’s basal sediment age places the timing of lake-level rise at ~1600 CE, which post-dates the end of the Inca Empire (1400–1532 CE) by several decades. The ubiquity of planktonic algae throughout the sediment profile suggests water levels remained high above the pot since its submergence. Paleoclimate data from the nearby Quelccaya ice core records indicate lake flooding followed a pronounced wet period beginning ~1520 CE. These data show the permanence of mean state changes in climate on the region’s hydrology, with clear implications for the study site (an important water resource for ~500,000 people) and other lakes in the rapidly warming Andes. - Some of the metrics are blocked by yourconsent settings
Publication Altitude Variation of Snow Cover in Nevado Huascaran and its Relationship to ENSO during the Period 2001-2016(2021-01-01)The Equilibrium Line Altitude (ELA) is the most fundamental altitude in glacier studies that is related to the ablation and accumulation process in the glaciers. These processes play an important role which depend on the local climate. Nevado Huascaran is located in the Peruvian Andean Mountain and its ELA is affected by events of El Nino-Southern Oscillation (ENSO). The objective of this study is to estimate the Altitude Variation of Snow Cover (AVSC) in the Nevado Huascaran and analyze its relationship to ENSO. The Digital Elevation Model (DEM), Fractional Snow Cover (FSC) and The Oceanic Nino Index (ONI) are used. These data are processed and analyzed using filters and Wavelet Analysis. The results showed an AVSC anomaly with a period of around 2.99 years. This is a clear evidence on how ENSO influences over the Nevado Huascaran. - Some of the metrics are blocked by yourconsent settings
Publication An Estimation of Past and Present Air Temperature Conditions, Water Equivalent, and Surface Velocity of Rock Glaciers in Cordillera Volcanica, Peru(2021-01-01)Rock glaciers (RG) are one of the most important geomorphological features in the Peruvian Andes. However, the local characteristics of RG have barely been studied or remain unknown. The aim of this research was to characterize past and present conditions of the RG located in Cordillera Volcanica in the southern of Peru. For this purpose, an inventory of RG was carried out and modern and past regional mean air annual temperatures (MAATs) were calculated. We estimate the water equivalent of RG to assess their importance as possible storage of frozen water for past and present conditions using an empirical rule. In addition, the local surface velocity of RG was obtained from Landsat 8 imagery. Within the study area, 187 RG were identified (surface area of 8.3 km2). Of these, 63 were classified as inactive, 39 as active and 85 as relict forms. The altitudinal distribution of RG ranges between 4616 to 5551 m a.s.l. (meter above sea level) where modern MAAT is 0.9°C. In the current conditions, relict RG are located in positive MAAT levels around 1.4°C, however, for the past conditions, relict RG were located in negative MAAT levels around -5°C. The amount of water stored in intact RG range between 28 and 64 million m3. Meanwhile, for past conditions (paleo-WVE), we estimated that volume stored within rock relict RG was between 16 and 35 million m3 (we assume an ice-rich layer of RG permafrost has between 20-45%). On the other hand, the average surface velocities of the active RG have been estimated between 1 to 10 cm/month. The finding of this research contributes to increasing knowledge about RG in the Peruvian Andes, however, further research is needed to understand the importance of RG as stores of frozen water during the past and present conditions. - Some of the metrics are blocked by yourconsent settings
Publication Análisis de escenarios ante desborde violento de la laguna Parón Para el nivel del peligro, provincia de Huaylas, departamento Ancash(2023-07-01)Evaluar los posibles escenarios ante el peligro por desborde violento de la laguna Parón, considerando procesos geodinámicos como avalanchas de hielo y caída de rocas para determinar el nivel de peligro de la laguna Parón. - Some of the metrics are blocked by yourconsent settings
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Patent APARATO PARA LA MEDICIÓN Y ALMACENAMIENTO DE VARIABLES HIDROMETEOROLÓGICAS ;LOARTE CADENAS Edwin Anibal ;LUJAN LEÓN Jean Pol Juniors ;MEDINA MARCOS Katy DamaciaVERDE MENDOCILLA César EliasEstación pluviométrica automática que comprende de un mástil de anclaje, con accesorios de fijación, tiene como instrumentos de medición un sensor de temperatura y humedad relativa dentro de una pantalla Stevenson, un anemómetro para la velocidad y dirección del viento, un sensor de presión atmosférica, un sensor para medir acumulación de precipitación que tiene un sistema desfogue automático y otro para medir el pH de dicha precipitación lo que permite determinar el nivel de contaminación de esta. Siendo una herramienta que entrega información más completa y que puede dar un mejor entendimiento de las condiciones del fenómeno hidrometereológico lo que conlleva a un mejor análisis y por ende mejores tomas de decisiones a los que corresponde. - Some of the metrics are blocked by yourconsent settings
Publication Arduino data loggers: A helping hand in physical geography(2023-06-01)Microcontrollers such as Arduino have been increasingly used by researchers to create and customise their own tools. In geography, microcontrollers are frequently used to design data loggers for monitoring purposes. We reviewed the use of Arduino in physical geography to unravel the opportunities and challenges of using off-the-shelf tools in research. We conducted a literature review, putting the retrieved information in perspective with our experimental work in mountainous and riverine landscapes in Chile and Peru. We show that the low cost and versatility of Do It Yourself (DIY) data loggers open research opportunities, extending the range of application of their expensive commercial counterparts. The possibility of connecting Arduino to a wide range of sensors, actuators, and wireless communication devices has helped to monitor rivers, glaciers, lakes, ice-waves, caves, and landslides, improving the temporal and spatial resolution of data collected in critical environments. Low-cost sensors have been extensively compared against expensive alternatives with good results, although they require thorough testing before field deployment due to the common existence of defective equipment. Building research equipment has several challenges. DIY data loggers might not be unconditionally accepted by environmental agencies, partially restricting their use to educational and research purposes. Failures in data loggers can be difficult to track, since they might be related to coding, electronic assemblage, or inadequate housing to withstand outdoor use. Yet, Arduino-based data loggers have helped scientists around the world in different stages of their career, especially in scarcely funded research endeavours. Arduino has boosted creativity and resourcefulness, paving the way for innovative monitoring strategies in physical geography. Person - Some of the metrics are blocked by yourconsent settings
Publication Author Correction: A pre-Inca pot from underwater ruins discovered in an Andean lake provides a sedimentary record of marked hydrological change (Scientific Reports, (2019), 9, 1, (19193), 10.1038/s41598-019-55422-1)(2020-12-01)An amendment to this paper has been published and can be accessed via a link at the top of the paper. - Some of the metrics are blocked by yourconsent settings
Publication Author Correction: A pre-Inca pot from underwater ruins discovered in an Andean lake provides a sedimentary record of marked hydrological change (Scientific Reports, (2019), 9, 1, (19193), 10.1038/s41598-019-55422-1)(2020-12-01)An amendment to this paper has been published and can be accessed via a link at the top of the paper.