State of the ice: how are Andean glaciers responding to climate change?

The Andes are the world’s most climatically and environmentally diverse mountain range and harbour a significant portion of its terrestrial ice reserves. Since the end of the Little Ice Age (∼1850), Andean glaciers have undergone a prolonged period of retreat and thinning, the rate of which has generally accelerated over recent decades in response to human-induced climate change. However, not all Andean glaciers are responding in the same way, and in some instances are undergoing changes that seem to contradict our understanding of glacier-climate relationships. This article summarises the extent of glacier change across the Andes, highlighting not only its overall magnitude but also its spatial variability. To illustrate this variability, this article also examines the curious behaviour of three prominent Chilean glaciers, case studies that will highlight the importance of understanding both the climatic and non-climatic factors driving glacier change in the Andes.