Results of the first update of the Provincial Glacier Inventory for the San Juan River Hydrological System, Argentina

Abstract

In Argentina, and specifically in the Province of San Juan, glaciers and periglacial landforms are protected under National Law No. 26,639 and Provincial Law No. 1,076-L, respectively. Both laws, in force since 2010, establish the protection of glaciers and periglacial environment landforms, recognizing them as strategic water reserves in solid state. At the local level, the provincial government is responsible for assembling and keeping the provincial inventory up to date as a management tool. This study presents the results of the first update of the Provincial Glacier Inventory for the San Juan River Hydrological System for the period 2015–2020. In this update, 685 glacial landforms (clean-ice glaciers, snow patches-glacierets, debris-covered glaciers, and debris-covered glaciers with rock glaciers) and 3,227 periglacial landforms (mostly rock glaciers) were identified, which collectively cover an area of 471.58±48.22 km² and represent 1.24% of the total area of the San Juan River Hydrological System. The estimated water equivalent volumes were 6.204±0.29 km³ (stored in glacial landforms) and 2.177±0.42 km³ (stored in periglacial landforms). By comparing these results with those obtained in 2017, it is observed that the area occupied by clean-ice glaciers decreased 18.74%, and the area covered by snow patches–glacierets decreased 65.15%. For the assessment of inventory quality, guidelines established by ISO Standard 19,157 were applied, with the omission, commission, and uncertainty indices determined during the mapping and digitization processes. This work primarily contributes to compliance with the provincial regulatory framework, enhancing our understanding of the current state of the cryosphere and its evolution in recent years.