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Climate regime and Sensitivity of Asian Glaciers Revealed by GAMDAM Glacier Inventory ClimDev 14 Jan. 2015 Akiko Sakai and Koji Fujita Nagoya University GAMDAM: Glacier Area Mapping for Discharge in Asian Mountains

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1. Climate regime and Sensitivity of Asian Glaciers Revealed by GAMDAM Glacier Inventory ClimDev 14 Jan. 2015 Akiko Sakai and Koji Fujita Nagoya University GAMDAM: Glacier Area Mapping for Discharge in Asian Mountains 2. 1st Motivation GlacierSea level change Water resource Glacier volume change Glacier Inventory Kb et al., 2012 Gardner et al., 2013 Discharge from glacier Karser et al., 2010 Immerzeel et al., 2010 Mass balance profile Area-altitude distribution of glaciers Altitude Positive Equilibrium Negative - + 3. Important parameter to estimate river runoff BUT Gridded data observed data 2nd Motivation at Karabat kak Glacier Observation Sakai et al. (in prep.) 4. Purpose Glacier 1. Create quality controlled glacier inventory 2. Estimate precipitation over glaciers using an ELA concept to reveal climate regime Target region: High Mountain Asia Glacier Area Mapping for Discharge in Asian Mountains 5. Coverage & Data source Manual delineation Data source LANDSAT (USGS) (1999-2003) 226 path-row 356 scenes Thermal band Contour line Slope Basin polygon Google Earth Delineation tests Two years, total 10 persons 82,776 glaciers in total no glacier Nuimura et al. (2014TCD, in 2nd review) 6. GAMDAM vs. ICIMOD HKH region Area (103 km2) GAMDAM 40.3 ICIMOD 40.6 Each 0.50.5 degree grid cell Consistent each other Nuimura et al. (2014TCD, in 2nd review) 7. Median elevation of GAMDAM GAMDAM Glacier Inventory & ASTER-GDEM2 Glacier Inventory of China (Shi, 2008) Nuimura et al. (2014TCD, in 2nd review) 8. Median Altitude vs. Observed ELA Mass balance at median elevation = 0 (in the past few decades) Braithwaite & Raper (2009) ELA observation at 10 glaciers Dyurgerov (2002); Fujita & Nuimura (2011) Balanced budget ELA = Median glacier elevation ELA: equilibrium line altitude mass balance =0 rmse = 71 bias = + 2.8 GAMDAM glacier inventory + GDEM2 Observation Sakai et al. (2014TCD, in revision) 9. Calculating Optimized Precipitation at ELA GAMDAM Glacier Inventory Input data Air temperature (level) Solar radiation(surface flux ) Wind speed (surface flux 10m) Relative humidity (surface) precipitation=APHRODHITE Ap Mass balance model Fujita & Ageta (2000) (energy balance model) Yatagai et al. (2009, 2012) Sakai et al. (2014TCD, in revision) 10. APHRODITE precipitation Yatagai et al. (2009, 2012) 11. Optimized precipitation at ELA Sakai et al. (2014TCD, in revision) 12. Validation Winter Balance- Observed data at 12 glacier Dyurgerov (2002) 1979-2004 Validated by observed winter balance rmse to observation Aphrodite snow = 503 mm Optimized snow = 292 mm Sakai et al. (2014TCD, in revision) 13. Summer accumulation Winter accumulation JJA precipitation ratio Analysis Ta vs. Pr at ELA- Summer accumulation Winter accumulation Sakai et al. (2014TCD, in revision) 14. Summary & Perspectives A novel GAMDAM glacier inventory Optimized precipitation at ELA Spatially heterogeneous glacier response over the High Mountain Asia The GAMDAM will be provided/merged to Randolph v5 within this year Contact: Akiko Sakai Contributions of Sensitivity, dAT and dPR to changes in glaciers