Science Source

Historically unprecedented global glacier decline in the early 21

Observations show that glaciers around the world are in retreat and losing mass
States that glacier monitoring activities—internationally coordinated for over a century—provide an unprecedented dataset of glacier observations from ground, air and space
States that glacier studies generally select specific parts of these datasets to obtain optimal assessments of the mass-balance data relating to the impact that glaciers exercise on global sea-level fluctuations or on regional runoff
Provides an overview and analysis of the main observational datasets compiled by the World Glacier Monitoring Service (WGMS)
The dataset on glacier front variations (approximately 42,000 since 1600) delivers clear evidence that centennial glacier retreat is a global phenomenon
Finds that intermittent readvance periods at regional and decadal scale are normally restricted to a subsample of glaciers and have not come close to achieving the maximum positions of the Little Ice Age (or Holocene)
Glaciological and geodetic observations (approximately 5,200 since 1850) show that the rates of early 21st-century mass loss are without precedent on a global scale, at least for the time period observed and probably also for recorded history
Concludes that this strong imbalance implies that glaciers in many regions will very likely suffer further ice loss, even if climate remains stable