The Urubamba and Vilcabamba mountain ranges are two geological structures belonging to the Andes in the southern part of Peru, which is located in the tropical region. These mountain ranges are especially located within the transition area between the Amazon region (altitudes close to 1’000 m a.s.l.) and the Andes. These mountains, with a maximum height of 6’280 m a.s.l. (Salkantay Snow Peak in the Vilcabamba range), are characterized by glaciers mainly higher than 5000 m a.s.l. Here we present a study on the evolution of the ice cover based on “Landsat 5” images from 1991 and 2011 is presented in this paper. These data are freely available from the USGS in a georeferenced format and cover a time span of more than 25 years.

The Peruvian Andes host about 71% of all tropical glaciers. Although several studies have focused on glaciers of the largest glaciered mountain range (Cordillera Blanca), other regions have received little attention to date. In 2011, a new program has been initiated with the aim of monitoring glaciers in the centre and south of Peru. The monitoring program is managed by the Servicio Nacional de Meteorología e Hidrología del Perú (SENAMHI) and it is a joint project together with the Universidad San Antonio Abad de Cusco (UNSAAC) and the Autoridad Nacional del Agua (ANA). In Southern Peru, the Quisoquipina glacier has been selected due to its representativeness for glaciers in the Cordillera Vilcanota considering area, length and orientation. The Cordillera Vilcanota is the second largest mountain range in Peru with a glaciated area of approximately 279 km2 in 2009. Melt water from glac...

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 ±...

The White Cordillera (northern Peru), with a glacial surface of 631 km2, is the largest glacierized mountain range in the Tropics. Due to the lack of physical data from most of its sub-basins, it is difficult to build a physical model to estimate the water resource flowing from the glaciers at the present time and a fortiori for the future. The most recent GCM simulations indicate a significant increase in the temperature and an accelerated shrinking of the glaciers. Consequently, we sought a model that would be based on the data available within instrumented sub-basins. A theoretical/conceptual water model makes it possible to quantify the local glacier contribution, which could then be applied to the other non-instrumented sub-basins. A total of 43.6% of Parón Lake's instrumented sub-basin area (47.4 km2) corresponds to glacial surfaces. Within this sub-basin, a smaller watershed (8.8...

En la presente investigación se tuvo como objetivo general determinar si la adición de Plástico Reciclado mejorara la resistencia del Pavimento Rígido en la Av. El Bosque, distrito de San Juan de Lurigancho 2023, el tipo de investigación es de metodología aplicada, nivel explicativo, con un enfoque cuantitativo y diseño experimental. Para el desarrollo de los resultados de laboratorio previamente se realizó el estudio de tráfico en la Av. mencionada, obteniendo un ESAL de 2,737,658 Tn, lo cual nos permitió determinar una resistencia mínima a compresión de 280 kg/cm2 y a flexión de 40 kg/cm2 en el diseño de la mezcla de concreto. Los resultados de laboratorio obtuvieron las siguientes resistencias a compresión y flexión, del concreto patrón, a los 7, 14 y 28 días de curado, su resistencia a compresión respectivamente fueron de 210.4 kg/cm2, 244.8 kg/cm2, 289.7 kg/cm2 y ...

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...

Almost all of the world’s glaciers in the tropical latitudes are located in the Central Andes (Peru, Bolivia, Ecuador and Colombia). Due to their high altitude, to the high level of radiation and to the tropical climate dynamics, they all are particularly threatened by climate change, as a result of not only warming, but also of changing variability of precipitation. Many glaciers are of crucial importance for the livelihood of the local populations and even for three capitals, Lima (Peru), La Paz (Bolivia) and Quito (Ecuador), which depend on them for water and energy supplies. This paper shows that after a period of increased flow due to the glacier melt disequilibrium, the available water resource will decrease along with the rapid shrinking of the glaciers considered as water reservoirs. The case of the Cordillera Blanca (Peru) is analyzed more in detail with the mid-term (20 years...

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...

The main objective of this work is to analyze the influence of cloud cover on shortwave radiation incident of the Nevado Coropuna during 2015-2016. In this presentation they propose to discuss that Arequipa, during the day, has more clouds between December to March above 80%. At night the cloudiness diminish significantly, hourly there are more clouds in the afternoon. The NC has a similar pattern, and there is a difference among the oriental and occidental side. Also, propose the cloudiness radiation has a high impact in the incident shortwave, in clear moments the radiation could reach 1200 W/m2, meanwhile with cloudiness this does not pass the 600 W/m2. In the dry period, generally there are not clouds; in the conventional meteorological stations are found predominantly high clouds, cirrus.

Ground Penetrating Radar (GPR) survey was carried out to estimate the ice thickness and mapping the bedrock topography at Znosko glacier on King George Island, Antarctic Peninsula during 25 th Peruvian Antarctic Expedition (2018). GPR surveying did at 5.2 MHz frequency with a 16 m antenna gap (transmitter and receiver). The mean ice thickness profiles vary from 7 to 123 m across the 350 m profile length. This high-resolution survey also identified a different type of ices and glaciological features which will help in modelling the nature of the glaciers in the future.

En el Perú, se observa un proceso de retroceso glaciar desde hace más de 30 años. El área de estudio de este artículo es la cordillera Blanca, la formación glaciar más importante del país, ubicada en el ramal occidental de los Andes del norte del Perú (latitud sur: 7° 57’-10° 13’ y longitud oeste: 77° 17’-78° 18’). Usando el inventario de glaciares del Perú publicado por Hidrandina (1989), basado en fotografías aéreas para los años 1962 y 1970, y utilizando imágenes Aster para el lapso 2004-2006, se ha calculado que entre los periodos 1962-1970 y 2004-2006, la superficie glaciar para toda la cordillera Blanca ha pasado de 728 +/– 25 km2 a 498 +/– 23 km2 , y que su volumen calculado por una relación empírica ha disminuido de 50 +/– 1,2 km3 a 31,2+/– 0,75 km3 . Además, una ecuación calibrada para el periodo actual (2003-2007) permitió calcular la Alti...

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...

This research aims to explain the influence of climatic variables (temperature and precipitation) in King George Island (KGI) glacier shrinkage on the Antarctic Peninsula. It employed Landsat satellite images from 1989 to 2020, climatic data and ONI index from 1980 to 2019. King George Island glaciers have lost 10% of their coverage in the last 31 years. Greater glacier shrinkage was shown until the first mid-period assessed, while the retreat rate slowed down for the second half of the studied period. Furthermore, of 73 KGI glaciers, 37% were marine- and landterminating, 42% were land-terminating and 21% were sea-terminating. Nonetheless, the decreases in the ice-coverage of marine-contact glaciers (35% of glacier coverage reduced) were higher than land-terminating glaciers (17% of glacier coverage reduced). There was a perceivable fluctuation in annual average air temperature for the 1...

The hydrological data (since 1953) of the Llanganuco basin (87.0 km2, 39% glacierized) show an increase of the glacial melting during the last quarter of the 20th century. These results were supplemented (since the end of 2000) by the data of the small basin of Artesoncocha (8.4 km2, 79% glacierized). The basin runoff is well correlated to the atmospheric temperature derived from the NOAA-NCEP re-analysis above the Cordillera Blanca. At the monthly time scale, the temperature is a good proxy of the glacier melting. The retreat of several glaciers in the Cordillera Blanca has been well documented for 50 years, highlighting an acceleration of the deglaciation in the mid-1970s. The use of these data of various origins permits one to model the behaviour of glaciers, especially the meltwater production, and then to predict their future evolution. The model was calibrated over the 1950–2000 ...

The main goal of this study is to determine the relationship between Shallap Glacier (SG) — Cordillera Blanca and King George Island (KGI) glaciers — Antarctic Peninsula and describe their features. Multi-temporal analysis with satellite imagery from 1989 to 2019 was made. The SG and KGI glaciers seem to be quite different. Nevertheless, preliminary results, in this research, show that approximately 74% of KGI glaciers have reduced their areas (below 20%) as same as the SG in the last 30 years. Indeed, SG (6 Km2) represents only 0.6% of the KGI glaciers (993.6 Km2), but each zone's different own factors seem to be shrinking glacier coverage at about similar proportions.

El presente artículo está orientado al análisis comparativo de diferentes modelos hidrológicos en la cuenca del río Chillón. Esta cuenca, ubicada aproximadamente a 130 kilómetros al sur de la ciudad de Lima, fue seleccionada para evaluar la capacidad de simulación de los modelos Génie Rural à 4 paramètres Journalier (GR4J), Soil Contribution (SOCONT), Hydrologiska Byrans Vattenbalansavdelning (HBV) y Sacramento Soil Moisture Accounting (SAC); considerando un enfoque de modelización conceptual semidistribuida. Se utilizó para ello el programa de modelización hidrológica e hidráulica RS MINERVE. Para los análisis comparativos de los modelos (GR4J, SOCONT, HBV y SAC) se delimitó un área de aproximadamente 1253 km2 de la cuenca del rio Chillón, denominado Cuenca Magdalena. Esta área se dividió en 25 subcuencas y 122 unidades hidrológicas aportantes llamadas “bandas a...

Glaciers in Peruvian Andes play an important role for local hydrology. To quantify the availability of glacier meltwater in a climate change scenario, surface energy (SEB) and mass balance (MB) models are required. However, few studies of SEB and MB modeling using coupled process-based models were carried out for this region. In this study, we use the newly updated COupled Snowpack and Ice surface energy and mass balance model in PYthon (COSIPY) in its 2-dimesnional spatially distributed version to simulate energy and mass fluxes over Artesonraju Glacier, Peruvian Andes, from 2016 to 2018. A glacier mass balance program was started at this glacier in 1995, with installation of a network of 22 ablation stakes and two automatic weather stations were started operating since 2005. COSIPY is forced by weather parameters like solar radiation, air temperature, relativity humidity, air pressure,...

The Cordillera Vilcanota in the Southern Peruvian Andes is the second largest ice-covered Cordillera in Peru (after the Cordillera Blanca) and serves for the Cusco Region as a temporary water storage for fresh-water and hydropower generation and irrigation. Despite the Cordillera Vilcanota’s size and socio-economic relevance, there has so far no comprehensive baseline data been available for climate and glacier evolution. In the framework of two jointly launched –Peruvian-Swiss climate change impact and adaptation programs (Climate Change Adaptation Programm - PACC; Glacier Change Adaptation and Desaster Risk Reduction Programm - Glacier 513) significant efforts have been undertaken and are on the way to create a climate, glacier and hazard baseline for the Cordillera Vilcanota. Because of the remoteness of the area and the scarcity of available data, multiple sources such as climate...

Field and modelling based research indicates that for tropical glaciers, variations in snow cover and the altitude of the snow line via albedo effects are among the most crucial factors to explain the differences in annual glacier mass balance variability. It is therefore essential to identify the height of the phase change during precipitation events and its coupling with glacier mass balance. This knowledge is also fundamental to assess possible future impacts of e.g. changing air temperatures on glacier mass balances at low latitudes. However, the knowledge on heights of phase changes and air temperature during precipitation events is severely limited by the small number of meteorological measurements at high altitudes in the tropics and the Himalaya. Additionally, their one-dimensional type of observation that cannot appropriately account for the variations along the vertical dimensi...