Agua Negra basin
Rock glaciers (active)
Debris covered glaciers
WP2: Ice content and water storage
capacities of blockslopes and taluses
Direct and indirect measurements of the internal
hydrological structure of selected blockslopes and
taluses will be obtained to investigate water storage
capacities, ice contents and their changes (see Fig. 2b).
Repeated geophysical prospections (Electrical
Resistivity Tomography (ERT), Seismic Refraction
Tomography (SRT), Ground-Penetrating Radar (GPR))
on periglacial landforms will provide detailed images of
the active layer thickness, subsurface composition and
internal structure. The geophysical data will be used as
input for the Four-Phase Model (Hauck et al. 2008,
2011) (see Fig. 1). In addition, temperature and
humidity loggers (iButtons, TDR sensors) will be
installed at different depths within the active layer
allowing for calculations of thermal gradients, active
layer thicknesses, and indirectly the duration of snow
cover and minimum thickness.
ERT & SRT profiles
This project is funded by the Deutsche Forschungs-
gesellschaft (DFG –German Research Foundation).
The authors would also like to express a special
thanks to their cooperation partners from IANIGLA-
CONICET Mendoza, above all Dr. Fidel Roig and the
Geocryology Research Group, as well as all
contributors from the University of San Juan,
especially Cristian Villarroel and Andrés Lopez.
Halla, C., Blöthe, J.H., Tapia Baldis, C., Trombotto, D., Hilbich, C., Hauck, C., Schrott, L., 2021. Ice content and interannual water storage changes of an active rock glacier in the dry
Andes of Argentina. The Cryosphere, 15,1187-1213.
Hauck, C., Bach, M., Hilbich, C., 2008. A 4-phase model to quantify subsurface ice and water content in permafrost regions based on geophysical datasets. 9, Institute of
Northern Engineering, University of Alaska Fairbanks, Fairbanks, Alaska.
Hauck, C., Böttcher, M., Maurer, H., 2011. A new model for estimating subsurface ice content based on combined electrical and seismic data sets. The Cryosphere, 5(2), 453-468.
IANIGLA-CONICET, Ministerio de Ambiente y Desarrollo Sustentable de la Nación (2018). IANIGLA-Inventario Nacional de Glaciares. Informe de la subcuenca del río Blanco.
Cuenca del río San Juan, Pp.62.
Schrott, L., 1996. Some geomorphological-hydrological aspects of rock glaciers in the Andes (San Juan, Argentina). Zeitung für Geomorphologie, Supplementband 104,161-173.
Schrott, L., Götz, J., 2013. The periglacial environment in the semiarid and arid Andes of Argentina - hydrological significance and research frontiers. In: Borsdorf, A. (Ed.):
Forschen im Gebirge. IGF-Forschungsberichte, 5, 53-62.
World Glacier Monitoring Service (WGMS), 2020. Global Glacier Change Bulletin No. 3 (2016-2017). Zemp, M., Gärtner-Roer, I., Nussbaumer, S. U., Bannwart, J., Rastner, P., Paul,
F., Hoelzle, M. (Eds.), ISC(WDS)/IUGG(IACS)/UNEP/UNESCO/WMO, Zurich, Switzerland, 274 pp., publication based on database version: doi:10.5904/wgms-fog-2019-12.
Investigating the spatial occurrence and hydrological significance of permafrost
in talus- and blockslopes in the Agua Negra catchment / Argentina
Tamara Koehler(1), Melanie A. Stammler(1), Diana A. Ortiz(1,2), Dario Trombotto-Liaudat(3) and Lothar Schrott(1)
(1) Department of Geography, University of Bonn, Meckenheimer Allee 166, 53115 Bonn, Alemania,
(2) Department of Geophysics and Astronomy, National University of San Juan,
Av. Ignacio de la Roza 590, San Juan, Argentina
(3) Geocryology, Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (IANIGLA), Mendoza, Argentina
Fig. 2: a) Location of the ANC in the semi-arid Andes of Argentina including the positions of six gauging stations and
one climate station along the AN river. Perennial snowfields and (rock) glacier areas are taken from the National
Glacier Inventory (IANIGLA-CONICET, 2018) (modified compilation after Hinzer, 2020); b) blockslopes and taluses, with
the anticipated location of geophysical surveys and the temperature and humidity measurements in the active layer.
WP3: Hydrological regime of the Agua Negra basin
Despite the growing evidence of the hydrological significance of periglacial landforms, permafrost hydrology is insufficiently represented
in numerous studies on mountain systems and processes. First discharge measurements in the upper ANC revealed that water released
from the active layer and seasonally frozen ground may constitute approximately 30 %of total discharge during the summer months
(Schrott, 1996). To enable distinguishing between the different water sources and their respective contribution to runoff, continuous
water discharge measurements will be conducted at six gauging stations (incl. repeated salt-dilution measurements at different water
levels to establish rating curves) along the longitudinal profile of the Agua Negra river (see Fig. 3a). Bucket measurements on small
permafrost springs (see Fig. 3b), water sampling for isotopic composition and hydrochemical analyses as well as hydrograph separations
will further enable deciphering the runoff contribution from different water sources (snowmelt, glacier melt, meltwater from active
layer) and tributaries. The quantitative estimation of this non-glacial contribution to the overall discharge will enrich our knowledge on
the hydrological importance of Andean permafrost.
Fig. 1: a) Results of the (a) ERT, (b) SRT surveys and (c) four-phase models for ice
(fi) and water (fw) content showing the internal structure of Dos Lenguas rock
glacier. High values of ice content and water bodies underline the hydrological
significance of the landform (Halla et al., 2021).
Introduction & Objectives
The Andean cryosphere hosts major freshwater sources for proximal and distal inland lowlands in river catchments especially in arid and semi-arid regions, providing runoff and
groundwater recharge. A unique characteristic of the dry Andes is the extensive periglacial belt that frequently stretches >1500 m of elevation (Schrott and Götz, 2013). Many
watersheds in the semiarid Andes of Argentina are not at all glacierized (ice glacier) but generate numerous creeks and small rivers, particularly in areas above 4000 m altitude
where large blockslopes, taluses and rock glaciers are abundant (IANIGLA-CONICET, 2018). The hydrologic system of the Agua Negra catchment (ANC) (ca. 30ºS and 69ºW, San Juan
Province) (see Fig. 2a, b) shows specific characteristics of dry mountains with runoff contributions from the relatively small glacier cover (~1,7 km² or roughly 3 % of the catchment),
low annual precipitation (appr. 150-250 mm/yr), seasonal snowmelt (from ephemeral and isolated perennial snow fields) and the meltwaters from areas underlain by (degrading)
permafrost (WGMS, 2020). The objective of the project “Spatial occurrence and hydrological significance of Andean permafrost, Agua Negra, Argentina (HyPerm)” is to study the
spatial distribution, geomorphic characteristics and hydrological significance of Andean mountain permafrost in the so far overlooked taluses (including protalus ramparts) and
blockslopes. Findings from our previous DFG project “PermArg”on rock glaciers will be integrated and extended using an ambitious multi-method approach that is organized in
different work packages (WPs).
Fig. 3: a) GS3on 3920 m a.s.l. measuring the discharge
from the glacierized upper catchment, b) bucket
measurement at Dos Lenguas rock glacier spring.
WP1: Climatic, topographic and lithological
controls of the spatial distribution of
taluses, blockslopes, and (rock) glaciers
Building on publications and high-resolution satellite
imagery, a regional cryogenic inventory particularly
focusing on blockslopes and taluses will be compiled
complementing the existing inventory “Inventario
Nacional de Glaciares”(IANIGLA-CONICET, 2018).
Repeated UAV-derived digital elevation models will be
used to detect and calculate surface changes of
relevant periglacial landforms. Both approaches allow
to assess the landforms’ hydrological importance, as
major cryospheric water sources and reservoirs in the
catchment will be identified and analysed (incl.
statistical analysis of distribution, topography and cli-
matic parameters). A first quantitative assessment by
planimetric delineation indicates that 70%of the
surface area in the upper ANC is covered by
blockslopes and taluses (see Fig. 2b).
Freshwater supply from the glacierized mountain catchments like the upper ANC is of outmost importance, as it represents the major water source for irrigation, industry and
domestic use. The protection of the glacial and periglacial environment has entered Argentina’s political and social agenda with a statute approved in 2010 (Schrott and Götz, 2013).
However, a comprehensive study which quantifies the contribution of the widespread periglacial landforms to the overall runoff of Andean mountain streams is still lacking. In times
of water scarcity and global warming special attention should be drawn to this issue. The “HyPerm”project will address a significant research gap and further allow determining with
greater precision the distribution and hydrological significance of permafrost in the region of the dry Andes as well as the influence of climatic, topographic and lithological
parameters on the permafrost conditions of these landforms. This will add to a more accurate estimation of solid-state water reserves stored in periglacial landforms of arid regions.