What role do the Andes Mountains play concerning Mendoza's vineyards?

The Andes Mountains play a crucial role in the viticulture of Mendoza by blocking rain from the west and providing a vital source of water through snowmelt. Mendoza typically experiences a semi-arid climate; thus, rainfall is limited. The mountains trap moist air from the Pacific Ocean, resulting in rainfall predominantly occurring on the western side of the range. This creates a rain shadow effect over Mendoza, resulting in drier conditions ideal for growing grapes.

Additionally, during the warmer months, the snow on the Andes melts, providing a consistent water source that irrigates the vineyards. This natural irrigation is essential for viticulture in an otherwise dry region, allowing for the cultivation of high-quality grapes. The strategic positioning of the Andes not only impacts water availability but also helps regulate the vineyard microclimates, contributing significantly to the overall success of the wine production in Mendoza.