The Perito Moreno glacier located in Argentine Patagonia is the third largest reserve of fresh water. For reasons that are unclear the glacier is growing in contrast to the majority of glaciers worldwide that are thinning and shrinking. In Patagonia, the majority of glaciers and ice caps have reacted particularly dynamically to increases in temperatures and there is evidence the volume loss from mountain glaciers and ice caps are the main contributor to recent global rises in sea levels.