Hydrological and depositional processes associated with recent glacier recession in Yanamarey catchment, Cordillera Blanca (Peru)
Graphical abstract
Introduction
The almost worldwide increase in air temperature during the last century has caused a reduction in the extent and volume of ice in the majority of the world's mountain areas (Oerlemans, 2005, Vincent et al., 2013, Marshall, 2014). A common process associated with glacier retreat is the formation of new lakes in the over-excavated basins, and an increase in water levels in existing lakes. As hydrological (runoff and glacier meltwater) and geomorphological (glacier deposits) processes in watersheds affected by recent deglaciation are very active, and the landscapes are very often carved in very unstable terrain (Benn and Evans, 2010), glacial lake outburst floods (GLOFs) pose a great risk to populations in their drainage areas (Carrivick and Tweed, 2013).
The Andes, in particular the Peruvian mountains, are a showcase for these hazards. There have been many reports of dramatic glacier recession in the Cordillera Blanca (Kaser et al., 2003, Mark and Seltzer, 2005, Vuille et al., 2003, Vuille et al., 2008) and other mountain areas including the Cordillera Huayhuash (McFadden et al., 2011), Cordillera Vilcanota (Salzmann et al., 2013), Coropuna (Racoviteanu et al., 2007) and Huaytapallana (López-Moreno et al., 2014). Glacier recession accelerated in the Peruvian Andes over the three last decades of the 20th century (Kaser and Georges, 1999, Francou and Vincent, 2007, Raup et al., 2007, Burns and Nolin, 2014). Thus, from 1970 to 1997 the glacier coverage in Peru declined by > 20% (Bury et al., 2011, Fraser, 2012), and this has been associated with higher lake levels and a marked increase in landslides, flash floods and mud flows, often with dramatic consequences (Portocarrero, 1995, Carey, 2005, Carey et al., 2012). However, because of a relative lack of data, the hydrological response in terms of total water available and changing seasonal patterns associated with this recession has been less studied, even though in some catchments 50% of the net runoff is from glacier melting, and can constitute almost 100% during the dry season (Bury et al., 2011, Baraer et al., 2012). Available information has provided evidence that glacier recession is leading to an increase in interannual variability in runoff in Cordillera Blanca (Kaser et al., 2003). Bury et al. (2011) reported that glacier retreat in some catchments of Cordillera Blanca has caused an increase in runoff, although this may be temporary and will be probably be followed by a decrease in water yield as the glaciers become smaller. They also suggested possible shifts in the seasonality of stream hydrographs. Such results were later supported by Baraer et al. (2012) confirming a transition during the 1970s in the discharge parameters of many rivers draining the Cordillera Blanca, including the Querecocha watershed, resulting in a decline in dry-season surface water availability after a period characterized by increasing runoff.
In addition, based on available hydrological records and isotopic analysis of water samples, Mark et al. (2010) reported a continuous decrease in the specific discharge from the most glaciated catchments of Cordillera Blanca, and a relatively higher proportion of water originating from glacier melt (a decreasing δ18O trend).
Although an intensification of geomorphic processes parallels deglaciation, changes in the depositional processes in the deglaciated watersheds (sediment transport and rates of delivery) have not been investigated so far in the most recently deglaciated areas of the Andes. Newly formed lakes offer a unique opportunity to study how hydrological and depositional processes interact in these new basins, and so help to evaluate associated hazards (Michelutti et al., 2015). Indeed, previous studies demonstrated that lake sediment records from the tropical Andes can be used to identify changes in the extent of climate mediated up-valley ice cover (Rodbell et al., 2008, Stansell et al., 2013, Stansell et al., 2014), and the possible content of pollutants on ice and sediments of Andean glaciers and lakes respectively (Cooke et al., 2009, Pavlova et al., 2014, Eichler et al., 2015).
In this study we investigated the recent evolution of the Yanamarey glacier and the Querococha watershed, which is one of the most studied glacier hydrology sites in the Peruvian Cordillera Blanca. Regular observations of glacier extent and climate variables associated with hydropower production, recorded since the 1970s by the Huaraz-based Peruvian Office of Glaciology and Lake Security (Carey, 2005, Mark and Seltzer, 2005, Mark and Seltzer, 2005, Bury et al., 2011), include reports of changes in glacier extent, the retreat of glacier fronts, and direct measurements and estimates of the evolution of the mass balance. We used Landsat TM images at an almost annual resolution to study the evolution of glacier surfaces in the two glaciated sectors of the Querococha catchment, providing the most detailed and updated report of glacier retreat in the catchment and the first assessment of the increasing surface covered by lakes in the region. Short sediment cores from Yanamarey Lake, in the headwater of the Querococha watershed, were used to investigate the evolution of lake depositional processes since the mid of the 20th century. Data on runoff from Yanamarey Lake has previously been used to characterize the water balance of these headwater areas (Baraer et al., 2012); these data were updated (2002–2014) and related to the evolution of climate and the glaciers. This is the first survey of a newly formed proglacial lake including sediment cores in the Andean region. Our approach relies on the fact that the hydrology of proglacial lakes is closely related to the fluctuations in glacier retreat velocity occurring upstream, and it will also affect the erosional and depositional processes in foreland areas, as well as the transport and deposition of heavy metals that may strongly impact downstream water quality. This topic is addressed through the integration of available climatological, hydrological and remote sensing data with lake sediment analyses. It improves the reconstruction of the glacier retreat evolution, its relationship to climate, and the impacts on the hydrology and sediment dynamics (erosion and deposition) in the catchment.
Section snippets
Study area
Yanamarey Lake (9°40′S; 77°15′W) is at approximately 4600 m a.s.l., has a drainage surface area of 3.5 km2 (Fig. 1), and partially covered by glaciers (1.4 km2). The Yanamarey Lake occupies an over-excavated basin in the bedrock, bounded by young lateral moraines on both margins and a terminal moraine that were probably deposited during the last period of maximum ice extent (the Little Ice Age: LIA). Up to the 1960s the recent lake basin was completely occupied by the glacier, and the Landsat
Processing of remote sensing data
We reviewed all available Landsat Thematic Mapper (TM) and Landsat Enhanced Thematic Mapper (ETM +) images from the archives of the United States Geological Survey (USGS, http://landsat.usgs.gov/; last accessed 1 August 2015). Most studies based on Landsat data consider ETM + and TM radiometry to be comparable. A total of 19 images of ice-covered areas and the locations of snowlines for the period 1974–2014 were processed (Table 1). The images were acquired for the dry season (June–August) due to
Glacier retreat and hydrological response
Fig. 2 shows the evolution of glaciers beneath Yanamarey Peak and the locations of new lakes resulting from glacier retreat. In 1975 the glaciers of the Yanamarey north and south had a total area of 3.5 km2, and approximately two-thirds of Yanamarey Lake was occupied by the glacier. By 2014 the glacier comprised three ice masses having a total area of 1.4 km2, the glacier front was 1 km upstream of the inlet of the lake, and 10 new small lakes (generally < 1 ha) had formed in the recently
Yanamarey Lake depositional evolution
The evolution of the Yanamarey glacier prior to the mid-20th century is not known, but it is conceivable that it retreated further up the watershed during preceding warmer Late Holocene phases, leaving the Yanamarey basin ice-free and facilitating the development of a lake. During colder periods, including the LIA, the glacier expanded over the lake and probably eroded some of the sediments. It is likely that the frontal moraine enclosing the Yanamarey Lake basin represents the maximum extent
Conclusions
This work represents the first study in the Andes that combines information on detailed temperature and precipitation trends, almost annual evolution of ice covered area by glaciers and increasing area flooded by new lakes, runoff, and a proglacial lake survey based on sediment cores. Despite the limited age control of lake sequence, the two depositional unit identified based on contrasted annual thickness, grain size, lamination features and geochemical composition clearly match with the two
Acknowledgements
This study was supported by the project “Creación de una base de datos climática de calidad para el estudio del cambio climático de las montañas del Peru-COOPB20042”, funded by the Spanish Research Council (CSIC).
References (54)
- et al.
Using atmospherically-corrected Landsat imagery to measure glacier area change in the Cordillera Blanca, Peru from 1987 to 2010
Remote Sens. Environ.
(2014) Living and dying with glaciers: people's historical vulnerability to avalanches and outburst floods in Peru
Glob. Planet. Chang.
(2005)- et al.
Proglacial lakes: character, behaviour and geological importance
Quat. Sci. Rev.
(2013) - et al.
Radiometric normalization of multitemporal high resolution satellite images with quality control and land cover change detection
Remote Sens. Environ.
(2002) - et al.
Elevated stream trace and minor element concentrations in the foreland of receding tropical glaciers
Appl. Geochem.
(2011) - et al.
Development of methods for mapping global snow cover using Moderate Resolution Imaging Spectroradjorricter (MODIS) data
Remote Sens. Environ.
(1995) - et al.
The impact of glaciers on the runoff and the reconstruction of mass balance history from hydrological data in the tropical Cordillera Blanca, Peru
J. Hydrol.
(2003) - et al.
Evaluation of recent glacier recession in the Cordillera Blanca, Peru (AD 1962–1999): spatial distribution of mass loss and climatic forcing
Quat. Sci. Rev.
(2005) - et al.
A 14-kyr record from the tropical Andes: the Lago Chungara sequence (18°S, northern Chilean altiplano)
Quat. Int.
(2007) - et al.
Tracing bottom water oxygenation with sedimentary Mn/Fe ratios in Lake Zurich, Switzerland
Chem. Geol.
(2013)
Evaluating digital elevation models for glaciological applications: an example from Nevado Coropuna
Peruvian Andes. Global Planet. Change
The GLIMS geospatial glacier database: a new tool for studying glacier change
Glob. Planet. Chang.
Clastic sediment flux to tropical Andean lakes: records of glaciation and soil erosion
Quat. Sci. Rev.
Climate trends and glacier retreat in the Cordillera Blanca, Peru, revisited
Glob. Planet. Chang.
Proglacial lake sediment records of Holocene climate change in the western Cordillera of Peru
Quat. Sci. Rev.
Proglacial lake sediment records reveal Holocene climate changes in the Venezuelan Andes
Quat. Sci. Rev.
Effects of Landsat 5 Thematic Mapper and Landsat 7 enhanced Thematic Mapper Plus radiometric and geometric calibrations and corrections on landscape characterization
Remote Sens. Environ.
Climate change and tropical Andean glaciers: past, present and future
Earth-Sci. Rev.
Sedimentation in glacial lake Hitchcok, Massachusetts
Glacier recession and water resources in Peru's Cordillera Blanca
J. Glaciol.
Glaciers and Glaciation
Glacier recession and human vulnerability in the Yanamarey watershed of the Cordillera Blanca, Peru
Clim. Chang.
An integrated socio-environmental framework for climate change adaptation and glacier hazard management: lessons from Lake 513, Cordillera Blanca, Peru
Clim. Chang.
Preindustrial metal pollution in the South American Andes
Over three millennia of mercury pollution in the Peruvian Andes
Proc. Natl. Acad. Sci.
Protist abundance and carbon concentration during a Phaeocystisdominated bloom at an Antarctic coastal site
Polar Biol.
Pb pollution from leaded gasoline in South America in the context of a 2000- year metallurgical history
Environ. Chem.
Cited by (21)
The runoff changes are controlled by combined effects of multiple regional environmental factors in the alpine hilly region of Northwest China
2023, Science of the Total EnvironmentCitation Excerpt :Yang et al. (2021a, 2021b, 2021c) showed that NDVI was positively correlated with runoff through partial correlation analysis (p < 0.01). The reason for this phenomenon may be that the NDVI value of snow cover is lower, and the perennial snow melt makes the NDVI value of the region rise and resulting in more runoff (Bhatt et al., 2010; López-Moreno et al., 2017). After removing the influence of the other three factors, ET0 and runoff become significantly negatively correlated at all periodic scales (Fig. 6d-f).
Runoff change controlled by combined effects of multiple environmental factors in a headwater catchment with cold and arid climate in northwest China
2021, Science of the Total EnvironmentTopographic control of glacier changes since the end of the Little Ice Age in the Sierra Nevada de Santa Marta mountains, Colombia
2020, Journal of South American Earth SciencesCitation Excerpt :The latter was calculated using the INSOL module in ARC-GIS. This variable does not aim to be a direct proxy of the total incoming radiation that is deeply affected by cloudiness, but it has been proven as an effective topographic index to show relative spatial differences in incoming shortwave radiation in complex terrain (López-Moreno et al., 2017). The use of this variable in statistical spatial models is frequent as it represents a clear advantage compared to the use of slope aspect (Pons and Ninyerola, 2008).
Current and future glacier and lake assessment in the deglaciating Vilcanota-Urubamba basin, Peruvian Andes
2018, Global and Planetary ChangeCitation Excerpt :In combination with permafrost degradation (>5000 m asl.), this development bears multiple consequences, such as emerging hazards from unstable moraines, ice and rocks (Haeberli et al., 2017), changes in erosion and sedimentation rates (López-Moreno et al., 2017), as well as spatiotemporal alterations in both quantity and quality of mountain water resources (Drenkhan et al., 2015; Stark et al., 2012). As a result of glacier shrinkage, many high mountain lakes are currently developing in Peru (Colonia et al., 2017; Drenkhan et al., 2015; Emmer et al., 2016) and other glaciated mountain regions, such as the Alps (Haeberli et al., 2016a) and Himalayas (Gardelle et al., 2011; Kapitsa et al., 2017).
Snow cover and snow albedo changes in the central Andes of Chile and Argentina from daily MODIS observations (2000–2016)
2018, Remote Sensing of EnvironmentCitation Excerpt :If these ice/snow cover trends continue, runoff conditions will likely change, especially during spring, dry summers and periods of drought, affecting the future sustainability of freshwater resources in areas downstream of the central Andes (Peña and Nazarala, 1987; Delbart et al., 2015; Saavedra et al., 2016; Carey et al., 2017; López-Moreno et al., 2017). Whether this change in runoff will cause the low lying areas in the catchment to become wetter or drier is largely determined by local topography (Polk et al., 2017; López-Moreno et al., 2017). Directly influencing the surface energy balance, the downward trends in SAL revealed in this study (Fig. 4) may possibly result in positive feedbacks in regards to snow and ice melt.