Ilulissat Climate Days, Greenland, 4 June 2015 Greenland – a white spot on the map of the internationally coordinated glacier monitoring? Michael Zemp, Richard Armstrong, Florence Fetterer, Isabelle Gärtner-Roer, Martin Hoelzle, Fabia Hüsler, Andreas Kääb, Jeff Kargel, Nico Mölg, Samuel Nussbaumer, Frank Paul, Bruce Raup

Greenland – a white spot on the map of the int. coordinated glacier monitoring? Glaciers around the GIS  How much glacier ice around the GIS?  How fast are these glacier changing?  Do we have a double counting in sea level rise contribution from Greenland?

gtn-glaciers ¦ distribution ¦ changes ¦ conclusions International Council for Science (ICSU): “A basic requirement for advancing research is free and unrestricted international sharing of high-quality, long-term, and standardized data and information products.” As a consequence, the Global Climate Observing System (GCOS) set in place a Global Terrestrial Network (GTN) for all Essential Climate Variables in support of the United Nations Framework Convention on Climate Change (UNFCCC).

Glacier distribution around the Greenland Ice Sheet gtn-glaciers ¦ distribution ¦ changes ¦ conclusions  Weidick (1998): >70,000 km 2 Weidick (1998)

Glaciers surface area gtn-glaciers ¦ distribution ¦ changes ¦ conclusions  Weidick (1998): >70,000 km 2  Rastner et al. (2012):  20,280 glaciers > 0.05 km 2  89,720 km2 (CL0&CL1)  130,076 km2 (CL0&CL1&CL2)  70 Landsat scenes

gtn-glaciers ¦ distribution ¦ changes ¦ conclusions Rastner et al (2012)

Gärtner-Roer et al. (2014) Glaciers volume gtn-glaciers ¦ distribution ¦ changes ¦ conclusions  Radic & Hock (2010) based on WGI 17,865 km 3 = 44 mm SLE  Huss & Farinotti (2012) based on RGI 19,042 km 3 = 47 mm SLE  Radic & Hock (2010) based on WGI 17,865 km 3 = 44 mm SLE  Huss & Farinotti (2012) based on RGI 19,042 km 3 = 47 mm SLE  Uncertainty: 30-50% (Gärtner-Roer et al. 2013)

Glaciers volume gtn-glaciers ¦ distribution ¦ changes ¦ conclusions  Radic & Hock (2010) based on WGI 17,865 km 3 = 44 mm SLE  Huss & Farinotti (2012) based on RGI 19,042 km 3 = 47 mm SLE  Uncertainty: 30-50% (Gärtner-Roer et al. 2013) Knecht (2014)

Glacier changes gtn-glaciers ¦ distribution ¦ changes ¦ conclusions  Front variations from 78 glaciers  Back to mid 19 th century Leclercq et al. (2012)

Glacier changes gtn-glaciers ¦ distribution ¦ changes ¦ conclusions  Front variations from 78 glaciers  Back to mid 19 th century  Glaciol. balances from 8 glaciers  Mittivakkat since 1995  Freya since 2007  Amitsuloq  Geodetic balances from 1 glacier  Flade Isblink Ice Cap

Glacier changes gtn-glaciers ¦ distribution ¦ changes ¦ conclusions From glaciological and geodetic obs.:  Ba1980s/90s/00s: -0.6/-0.9/-1.1 m w.e. a -1  SLR contribution: Gt per year  …but based on very few glaciers!  …representativeness for SLR contr.? Zemp et al. (in press)

Glacier changes gtn-glaciers ¦ distribution ¦ changes ¦ conclusions From glaciological and geodetic obs.:  Ba1980s/90s/00s: -0.6/-0.9/-1.1 m w.e. a -1  SLR contribution: Gt per year  …but based on very few glaciers!  …representativeness for SLR contr.? From ICESat based on Bolch et al. (2013):  SLR contribution … ..28 Gt per year for C0&C1 ..41 Gt per year for C0&C1&C2  => 2.5 times the specific mass loss of the GIS  => up to 20% of the GIS contribution to SLR Bolch et al. (2013)

Do we have a double-counting in SLR contribution from Greenland? Gardner et al. (2013) gtn-glaciers ¦ distribution ¦ changes ¦ conclusions

Conclusions  Over the past five years, we have strongly improved our knowledge about glaciers around the Greenland Ice Sheet.  However, we still need… ..more, longer, and richer obs. series ..a better coordination between the glacier and the ice sheet research communities,  Need for glacier data?  (GCOS need a home for the ice sheet data…)

Kääb et al. (2013) Elevation changes from ICESat

gtn-glaciers ¦ distribution ¦ changes ¦ conclusions