Title | Historically unprecedented global glacier decline in the early 21st century |
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Author | Zemp, M; Frey, H; Gartner-Roer, I; Nussbaumer, S U; Hoelzle, M; Paul, F; Haeberli, W; Denzinger, F; Ahlstrom, A P; Anderson, B; Bajracharya, S; Baroni, C; Braun, L N; Cáceres, B E; Casassa, G; Cobos, G;
Dávila, L R; Delgado granados, H; Demuth, M N; Espizua, L; Fischer, A; Fujita, K; Gadek, B; Ghazanfar, A; Hagen, J O; Holmlund, P; Karimi, N; Li, Z; Pelto, M; Pitte, P; Popovnin, V V; Portocarrero, C; Prinz, R; Sangewar, C V; Severskiy, I;
Sigurðsson, O; Soruco, A; Usubaliev, R; Vincent, C |
Source | Journal of Glaciology vol. 61, no. 228, 2015 p. 745-762, https://doi.org/10.3189/2015JoG15J017 Open Access |
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Year | 2015 |
Alt Series | Earth Sciences Sector, Contribution Series 20150094 |
Publisher | Cambridge University Press (CUP) |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Area | world |
Lat/Long WENS | -180.0000 180.0000 90.0000 -90.0000 |
Subjects | surficial geology/geomorphology; Nature and Environment; glaciers; glacier surveys; glacial deposits; glacial history; glaciation; deglaciation; climatic fluctuations; massive ice; ice thicknesses; ice;
ice conditions |
Illustrations | location maps; tables; plots |
Program | Climate Change Geoscience Essential Climate Variable Monitoring |
Released | 2017 07 10 |
Abstract | Observations show that glaciers around the world are in retreat and losing mass. Internationally coordinated for over a century, glacier monitoring activities provide an unprecedented dataset of glacier
observations from ground, air and space. 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. In this study we provide an overview and analysis of the main observational datasets compiled by the World Glacier Monitoring Service (WGMS). The dataset on glacier front variations (?42 000 since 1600) delivers clear evidence that
centennial glacier retreat is a global phenomenon. 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 (?5200 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, as
indicated also in reconstructions from written and illustrated documents. This strong imbalance implies that glaciers in many regions will very likely suffer further ice loss, even if climate remains stable. |
Summary | (Plain Language Summary, not published) Glacier ice is a geological material formed by depositional/ densification processes and dynamic flow. Glacier fluctuations are high-confidence
indicators of climate change, integrating the fluxes of precipitation, air temperature, and solar radiation/cloud cover at the Earth's surface. Worldwide co-ordinated glacier measurements began over one-century ago allowing, herein, a unique
opportunity to examine more contemporary measurements in the long view. The paper provides evidence that centenary glacier retreat is a global phenomenon. This retreat continues to be fueled by negative glacier mass balances that are unprecedented
on a global scale at least since beginning of observational records and, as indicated by reconstructions from written and pictorial sources, even for the time period of recorded history. The largest negative mass balances have occurred in one of the
last two decades - depending on the region. The implications of the "imbalance" is that glaciers in many regions may undergo ice loss even under a constant climate. |
GEOSCAN ID | 296640 |
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