Monte Desert Monte Desert The Monte Desert is a South American ecoregion, lying entirely within Argentina and covering approximately the submontane areas of Catamarca, La Rioja, San Juan, San Luis and Mendoza Provinces, plus the western half of La Pampa Province and the extreme north of Río Negro Province. The desert lies southeast of the Atacama Desert in Chile, north of the larger Patagonian Desert, east of the Andes and west of the Sierra de Córdoba. The delineations between the Monte Desert, the Atacama Desert, and the Patagonian Desert are not exact and the desert seems to be more-or-less continuous with the
Patagonian Ice Sheet of more than 500,000 km³, of which about 4% remains glaciated today in two separated portions known as the Northern and Southern Patagonian Ice Fields. The ice-volume reduction contributed to a global sea-level rise of about 1.2 meters. However, during the first glacial period at the beginning of the Pleistocene ice extended to the present-day Argentine coast. With each successive glaciation it is known that the ice has stopped further and further to the west, with aridity always serving as the decisive factor halting glacier spread: it is believed that the east-west precipitation gradients during glacial periods were even steeper