In the last decade, unmanned aerial vehicles (UAVs) have been used for scientific research specially for glaciological applications in Antarctica. In the study an UAV was used to detect changes in Znosko glacier surface, map the glacier contour, snow line and estimate the geodetic mass balance. Znosko glacier (ZG) located in King George Island (KGI), Antarctic Peninsula has an estimated total area of 1.77 km2 (January 2020), a length of 1.9 km and maximum elevation of 300 metres above sea level (m a.s.l.). The aerial photogrammetric survey was carried out in two field campaigns (austral summer 2019 and 2020) during the XXVI and XXVII Peruvian Antarctic Operation using a Quadcopter for image acquisition. Our findings reveal a negative geodetic mass balance for the periods 2019–2012, 2020–2019 and 2020–2012 with −15.25, −2.76 and −17.97 metre water equivalent (m w.e.) respe...

There is growing interest in the international scientific community in characterizing climate variability in Antarctica because of the continent's fundamental role in regulating the world's climate. Researchers have intensively studied the Antarctic Peninsula since the warming that began in the mid-1950s. This was followed by a subsequent cooling period over the last decades. For this paper, using the available data, we analyzed the variability in surface air temperatures at five meteorological stations located on King George Island (KGI) (a subantarctic island that is part of the South Shetland Islands); we also investigated the relationships between the air temperatures and large-scale atmospheric patterns from 1968 to 2019. In this study we found that summer temperatures are above 0°C from December to March and close to melting temperatures (extreme values) in spring and autumn; cons...

Glaciers are a key indicator of climate change. Since the second half of the 20th century several glaciers in Antarctica have retreated. In situ measurements of glacier mass balance in the Antarctic Peninsula and its surrounding islands are very scarce because this area is inaccessible due to rough terrain and inhospitable atmospheric conditions, but there is a necessity in study peripheral glaciers dynamics to know their future contribution to sea level rise. To fill this gap, remote sensing is an alternative tool to enable timely monitoring of dynamic glaciers and quantifying spatial-temporal changes. Here we combine remote sensing (satellite imaginary and aerial photos) and in situ measurements to calculate mass balance for the Znosko glacier (King George Island, Antarctic Peninsula) and compare the accuracy of this methods. Two field campaigns were carried out during the XXVI and XXV...

Study focus: Hydraulic infrastructure plays a fundamental role for energy production, drinking and irrigation water storage and flood control in regions with seasonal river flow. The highAndean Lake Sibinacocha has been regulated since 1988 to increase energy production of the Machupicchu hydropower plant. In this study, river streamflow changes are evaluated by analyzing precipitation and discharge trends using indicators of hydrologic alteration and ecoflow for natural (1965–1987) and altered (1988–2016) flow regimes. New hydrological insights for the region: For the altered flow regime, an ecodeficit of about 20% (compared to natural river flow) and an ecosurplus > 30% were found during the wet season (December-February) and dry season (June-August), respectively. These changes have reduced the risk of water shortage (dry season) and flood (wet season) and contribute to increasing...

La Ictiohematología es una herramienta de uso común con fines clínicos en peces de importancia económica, con un menor aporte en la comprensión de la fisiología del organismo en relación con su medio. En este contexto y frente a la escasa información publicada en el Perú de aspectos hematológicos de osteictios, se propuso caracterizar los leucocitos del pez angel Pterophyllum scalare (Lichtenstein, 1823) y determinar los valores de referencia cuantitativos. Este pez amazónico exportado como ornamental fue obtenido de un acuario de Lima-Perú. La extracción de la sangre, se llevó a cabo por el método de punción cardiaca, realizándose luego extensiones teñidas con Giemsa y con Wright, y se procedió a realizar el recuento leucocitario. Se relacionaron los parámetros biométricos [longitud estándar (mm), longitud total (mm) y peso (g)] con su caracterización leucocitaria...

La Ictiohematología es una herramienta de uso común con fines clínicos en peces de importancia económica, con un menor aporte en la comprensión de la fisiología del organismo en relación con su medio. En este contexto y frente a la escasa información publicada en el Perú de aspectos hematológicos de osteictios, se propuso caracterizar los leucocitos del pez angel Pterophyllum scalare (Lichtenstein, 1823) y determinar los valores de referencia cuantitativos. Este pez amazónico exportado como ornamental fue obtenido de un acuario de Lima-Perú. La extracción de la sangre, se llevó a cabo por el método de punción cardiaca, realizándose luego extensiones teñidas con Giemsa y con Wright, y se procedió a realizar el recuento leucocitario. Se relacionaron los parámetros biométricos [longitud estándar (mm), longitud total (mm) y peso (g)] con su caracterización leucocitaria...

The present article objective is to determine the net mass balance of the glacier Znosko for periods 2018-2019 and 2019-2020. It is situated on King George Island which belongs to the groups Shetland of the South, Antarctic Peninsula region. For this objective, during February 2018 a net of 19 stakes (which were controlled once during February 2019 and 2020) were installed on the glacier ablation zone, drilling in the accumulation zone and about flights using unmanned aerial vehicles (UAV) to control the glacier zone and geomorphological changes. For the year 2020, it was determined a glacier area of 1.71 ± 0.02 km2, moreover, using five different methods of interpolation, it was obtained on average, as a result, a specific net balance of -590.7 ± 46.6 mm w.e (in water equivalent) for 2018-2019 and -686.7 ± 28.2 mm w.e for 2019-2020, being the ELA altitude 146.5 ± 18.2 m and 144.2 ±...