Glaciers and the periglacial environment in Argentina have been protected by the Law since 2010. This legislation required the development of the first National Glacier Inventory (NGI), which was officially presented in May 2018 and based on satellite images spanning between 2004 and 2016. Here, we present the methods and results of the NGI, summarize the glaciers’ morphological and spatial characteristics, and compare our results to previous regional and global inventories. The NGI reveals an impressive variety of ice masses including rock glaciers, permanent snowfields, mountain and valley glaciers with varying amounts of debris-cover and large outlet glaciers. The Argentinean Andes contain 16 078 ice masses covering an area of 5769 km2 between 200 and 6900 m a.s.l. Comparison of the combined national inventories of Argentina and Chile (~30 000 glaciers and 28 400 km2) with the Randolph Glacier Inventory 6.0 for the Southern Andes (~16 000 glaciers and 29 400 km2), shows that there are large differences in extent and number of glaciers in some sub-regions. The NGI represents an improvement for a better understanding of Argentina's freshwater reservoirs and provides detailed information for the preservation and study of ice masses along 4000 km of the Southern Andes.

Los glaciares constituyen reservas hídricas en estado sólido y son componentes cruciales del sistema hidrológico de montaña. A pesar de su importancia, no existía en Argentina información precisa sobre el número, ubicación y tamaño de estos cuerpos de hielo. En el año 2010, se sanciona la Ley 26639 de “Presupuestos Mínimos para la Preservación de los Glaciares y el Ambiente Periglacial”, que tiene como principales objetivos proteger los glaciares considerados como reservas estratégicas de recursos hídricos y crear el Inventario Nacional de Glaciares (ING), donde se individualicen todos los glaciares y geoformas periglaciales que actúan como reservas hídricas con toda la información necesaria para su adecuada protección, control y monitoreo. El inventario y monitoreo del estado de los glaciares y del ambiente periglacial es llevado a cabo por el Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (IANIGLA-CONICET) con la coordinación de la autoridad nacional de aplicación de la ley, el Ministerio de Ambiente y Desarrollo Sustentable de Argentina (MAyDS). Este inventario se realiza en tres niveles que varían en complejidad y extensión espacial. En este trabajo se presentan los resultados preliminares obtenidos en el primer nivel, que consiste en el mapeo y caracterización de glaciares (descubiertos, cubiertos, manchones de nieve y de escombros) mediante sensores remotos. Estos datos son luego verificados en el campo en sectores seleccionados. Sobre un total de 70 cuencas y subcuencas delimitadas para el inventario se ha avanzado en 64. Hasta febrero de 2017, se han inventariado 15,482 glaciares que cubren una superficie de 5743 km2

Based on the recently released National Glacier Inventory (NGI), we analyzed the characteristics and the mass balance rates of ice masses in the Argentinean Central Andes (ca. 30°–37° S). The NGI provides unprecedented information on area, number and distribution of different ice masses, including debris-covered glaciers and rock glaciers. In the Central Andes, a number of 8,076 ice masses were identified covering a total area of 1767 km2. For the period 2000–2018, a general lowering of the ice surface was observed with a region-wide mass balance rate of −0.18 ± 0.19 m w.e. yr−1. Clear differences depending on the debris coverage of the different ice masses were identified, with mass balance rates ranging from −0.36 ± 0.19 m w.e. yr−1 for partly debris-covered glaciers to −0.02 ± 0.19 m w.e. yr−1 for rock glaciers. Considering different sub-periods, the region-wide mass balance rate was slightly positive (+0.12 ± 0.23 m w. e. yr−1) from 2000 to 2009 and negative (−0.21 ± 0.30 m w.e. yr−1) from 2009 to 2018. A comparison with the Randolph Glacier Inventory (RGI version 6.0) indicates that the NGI provides more detailed information regarding different type of ice masses whereas region-wide mass balance rates show limited sensitivity to the choice of the inventory. The inclusion of rock glaciers and “debris-covered ice with rock glacier” in the NGI causes mass balance rates to be slightly less negative than when using the RGI. Since the Central Andes are experiencing an unprecedented decade-long drought, our study provides crucial information to estimate current and future hydrological contribution of the different type of ice masses to river discharge in the arid subtropical Andes.