CPP-05. A Summary of the Global Glacier Landscape: The Largest Glaciers in the 19 Glacial Regions of the World

Not only are glaciers a beautiful part of our landscape that are retreating at an alarming rate, but they are also a source of fresh water and energy in many parts of the world. Glacier monitoring has been internationally coordinated for more than 125 years. Despite this long history, there is no authoritative answer to the popular question: “Which glaciers are the largest in the world?” This is partly due to the fact that researchers have completed many regional inventories of glaciers; however, global compendiums are scarce. Here, we present the first systematic assessment of this question and identify the largest glaciers in the world – distinct from the two ice sheets in Greenland and Antarctica. We identify the largest glaciers in the 19 primary glacier regions defined by the Global Terrestrial Network for Glaciers using two global glacier databases: The Global Land Ice Measurements from Space and the Randolph Glacier Inventory. Ranking glaciers by area is non-trivial. It depends on how a glacier is defined and mapped and also requires differentiating between glaciers and glacier complexes, i.e., contiguous glaciers that meet at ice divides such as ice caps and ice fields. It also depends on the availability of a homogenized global glacier inventory. Using separate rankings for glaciers and glacier complexes, we find that the largest glacier complexes have areas on the order of tens of thousands of square kilometers whereas the largest glaciers are several thousands of square kilometers and are located in the Antarctic, Arctic, and Patagonia.