Geoscience Reference
In-Depth Information
7 Conclusions
In light of strongly accelerated glacier wastage, there is an urgent need for further
investigations quantifying and projecting the changes in glacier mass and runoff, and their
importance for the Earth's hydrological cycle. We identify the following issues that need
special attention:
•
The current decline of the in situ glacier monitoring programs is a matter of concern.
Although the remote sensing techniques have overcome many obstacles encountered by
the traditional in situ observations, the latter are essential for calibration and validation
of glacier mass-balance and runoff models.
•
Despite the recent progress in the development of the global-scale glacier models, they
still suffer from the omission of physics-based simulation of glacier dynamics and
frontal ablation (calving and submarine melt).
•
The effect of flow of meltwater into groundwater aquifers or enclosed basins is
virtually unknown and should be addressed by coupling glacier mass-balance models
with global hydrological models.
•
For future scenarios, it is important that these hydrological models have the capacity to
model glacier retreat.
•
It is essential that glacier runoff is clearly defined in studies aiming to quantify the
contribution of glacier runoff to streamflow to avoid confusion and facilitate fair
comparison between studies.
Acknowledgments This study was supported by grants from NSF (EAR 0943742, EAR 1039008) and
NASA (NNX11AO23G, NNX11AF41G). H. Feilhauer assisted with Fig.
2
.
References
Abdalati W, Krabill W, Frederick E, Manizade S, Martin C, Sonntag J, Swift R, Thomas R, Yungel J,
Koerner R (2004) Elevation changes of ice caps in the Canadian Arctic Archipelago. J Geophys Res
109 (F04007). doi:
10.1029/2003JF000045
Adalgeirsdottir G, Johannesson T, Bjornsson H, Palsson F, Sigurdsson O (2006) Response of Hofsjokull and
southern
Vatnajokull,
Iceland,
to
climate
change.
J
Geophys
Res
111(F03001).
doi:
10.1029/
Adhikari S, Marshall SJ (2012) Glacier volume-area relation for high-order mechanics and transient glacier
states. Geophys Res Lett 39(L16505). doi:
10.1029/2012GL052712
Anderson B, MacKintosh A, Stumm D, George L, Kerr T, Winter-Billington A, Fitzsimons S (2010)
Climate sensitivity of a high-precipitation glacier in New Zealand. J Glaciol 56(195):114-128
Arendt A, Echelmeyer K, Harrison W, Lingle C, Valentine VB (2002) Rapid wastage of Alaska glaciers and
their contribution to rising sea level. Science 297:382-386
Arendt A et al (2012) Randolph glacier inventory: a dataset of global glacier outlines version: 2.0. GLIMS
Technical Report
Bahr DB, Meier MF, Peckham SD (1997) The physical basis of glacier volume-area scaling. J Geophys Res
102:20355-20362
Bahr DB, Dyurgerov M, Meier MF (2009) Sea-level rise from glaciers and ice caps: a lower bound. Geophys
Res Lett 36:L03501. doi:
10.1029/2008GL036309
Berthier E, Schiefer E, Clarke GKC, Menounos B, Remy F (2010) Contribution of Alaskan glaciers to sea-
level rise derived from satellite imagery. Nature Geosci 3:92-95
Bhatia MP, Kujawinski EB, Das SB, Breier CF, Henderson PB, Charette MA (2013) Greenland meltwater as
a significant and potentially bioavailable source of iron to the ocean. Nature Geo 6:274-278. doi:
10.
Bjornsson H (2002) Subglacial lakes and jokulhlaups in Iceland. Global Planet Change 35:255-271
