The SHARE contribution to the knowledge of the HKKH glaciers, the largest ice masses of our planet outside the polar regions

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1 The SHARE contribution to the knowledge of the HKKH glaciers, the largest ice masses of our planet outside the polar regions Claudio Smiraglia 1 with the collaboration of Guglielmina Diolaiuti 1 Christoph Mayer 2 Claudia Mihalcea 1 Marco Belò 3 University of Milan, Italy Bavarian Academy of Sciences ad Humanities, Germany Italian Glaciological Committee EvK2CNR, Italy Trimble-Italy

2 A few worms crawling about the heads of the valley (Freshfield, 1903). Very few exact reports are known about the variations of Central Asiatic glaciers. But the glacierized area of High Asia amounts to more than 50% of all glacierized areas outside the polar zones and is 33 times larger than that of the European Alps. The study of its variations is important not only because of its large extent, but also because it may help to illuminate the problem of the correlations between climate and glacier variations (Kick, 1962). The change or evolution of these glaciers is of great interest and importance for water resources, as well as for tourism, particularly for assessing the effect of global warming on runoff in Himalayan catchments (Nakawo et al., 1999).

3 HIMALAYAN GLACIERS Khumbu : 10 m of thickness reduction (KADOTA et al., 2000) North slope of Qomolangma (Mount Everest) and Xixiabangma 1960-up to now: yearly retreat rate m/a and m/a respectively (REN JIAWEN et al., 2006) Western Himalaya, Naimona nyi area from 1976 to 2003: glacier area decreased from km 2 to km 2 ; glacier areas shrank on average, during the periods , and , by 0.17, 0.19 and 0.77 km 2 per year respectively, thus suggesting that glacier retreat has been accelerating (QINGHUA YE et al., 2006). Western Himalaya, Himachal Pradesh, : specific mass balance of 0.7 to 0.85 m/a (water equivalent); this rate of ice loss is twice higher than the long-term (1977 to 1999) mass balance record for Himalaya thus indicating an increase in the glacier wastage rate : regression of the large glaciers whose terminal tongues were reaching the lowest levels (about 4000 m) with a thinning of -8 to -10 m below 4400 m (BERTHIER et al., 2007). Changri Nup : -140 m terminus reduction (SMIRAGLIA et al., 2007). Central Tibetan Plateau Geladandong mountain : the total glacier area decreased from 889 km 2 to 847 km 2, a reduction of almost 43km 2 (i.e. 4.8% decrease, or an average of 1.29 km 2 per year). Such variation of glacier area suggests an accelerating retreat in the recent years. The recession rates of glacier termini also were found to be increased (QINGHUA YE et al., 2006). Chenab, Parbati and Baspa basins: overall reduction in glacier area from 2077 km 2 in 1962 to 1628 km 2 at present, an overall deglaciation of 21% (KULKARNI et al., 2007). Khumbu Himal : the ice coverage decreased by about 5% with the highest retreat rates occurring between 1992 and 2001; downwasting rates, more than 20 m (>0.5 m per year) near the transition zone, between the active and the stagnant glacier parts of the debris-covered glacier tongues (BOLCH et al., 2008). Sagarmatha National Park : overall decrease in glacier area (c. 4.9%, from to km 2 ) (SALERNO et al., 2008).

4 In 1949, when I first saw the glacier, I felt as if all my sins were washed away and I had truly attained rebirth, the swami says. "But now, it is impossible to experience that Ganga of the past."

5 The Himalayan SHARE benchmark glacier : m CHANGRI NUP Fluctuations of the Changri Nup terminus (debris free front) from 1994 to 2005 (Smiraglia et al., 2007) Years Terminus fluctuations

6 KARAKORAM GLACIERS Central Karakoram glaciers : 13 glaciers advancing, some thickening ; exceptional numbers of glacier surges (HEWITT, 2005). Panmah Glacier : four tributaries of Panmah Glacier have surged in less than a decade, three in quick succession during this short period (HEWITT, 2007). Batura Glacier: stagnant terminus (SHRODER et al., 2007) Baltoro Glacier : stagnant terminus, downwasting and debris coverage increase (MAYER et al., 2006; SHRODER et al., 2007; SMIRAGLIA et al., 2008). Liligo Glacier : advance m (DIOLAIUTI et al., 2003; BELO et al., 2008). Central Karakoram glaciers : no reduction in the ice cover in the last three decades; since 1995 more than 35 glaciers advancing, mid-glacier thickening in a dozen others, sudden increase in glacier surges (HEWITT, 2004; HEWITT, 2009). Karakoram glaciers: most of the longer glaciers (Baltoro, Batura, Khurdopin) have been stagnant in the last century; even some of the debris free-type glaciers (Yazghil, Barpu) did not retreat significantly. Many glaciers had mainly shrunken by downwasting rather than by ice-frontal recession (ITURRIZAGA, 2007). Remote sensing studies reveal glacier advances and spatio-temporal clustering of surging glaciers. Satellite observations and climate data indicate advancing glaciers driven by climate (BISHOP, 2009)

7 by R. Rohoi, 2007

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9 The Karakoram SHARE benchmark glacier: BALTORO Spot Image, 1985

10 Digital Terrain Model, a 3D view by satellite images Mayer, 2004

11 Baltoro Glacier catchment definition: 1500 km 2 Baltoro Glacier area: 524 km 2 Baltoro main features: Elevation range: 3370 m 8611 m a.s.l km 2 drainage area: 524 km 2 glacier area 372 km 2 ablation area

12 BALTORO GLACIER Desio, m years Terminus fluctuations Mayer, 2004

13 A comparison with the Alpine SHARE benchmark glacier : FORNI Ghiacciaio dei Forni 1836 Ghiacciaio dei Forni Forni Glacier cumulated terminus variations -200 cumulated terminus variation time (years)

14 V. Sella, 1909 C. Mayer, 2004

15 1909, V. Sella 1953, A. Desio Another Karakoram SHARE benchmark glacier: LILIGO , M. Pecci 2004, M. Belò 1984, C. Smiraglia 2008, M. Gaetani

16 Liligo snout position in 1971 (source Corona, left picture) and in 2001 (source ASTER, right picture)

17 Tongue area of Baltoro and Liligo glacier, 2001

18 Velocity, debris thickness and ablation measurements

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20 Landsat, Aster 1999, 2000, 2001 SURFACE VELOCITY

21 Ablation derived from debris thermal resistance and debris depth (1-15 July, values in m) Debris thickness distribution derived from ASTER surface temperatures (by Mihalcea et al., 2008)

22 Information on comprehensive glacial survey is extremely scanty, and the accounts of occasional travellers and mountaineers over the years have little reliability. Maps are also misleading in their lack of distinctive indications for perennial snow and glacier cover (Leher and Harvath (1975). Is that description of our overall knowledge of Himalayan glaciers still pertinent today? Actually now new projects and methodologies are available to help us! GLIMS, Inventory of glaciers (Nepal, Pakistan, India, China), AWSs, SHARE

23 SHARE GLACIOLOGY NETWORK Himalaya: Changri Nup Glacier Karakoram: Baltoro Glacier, Liligo Glacier, Hinarche Glacier Alps: Forni Glacier Future topics: Distributing energy balance of debris covered glaciers Ice sail ablation and role of water ponds Dust and fine debris effect on ablation Accumulation at higher elevation, detection of the critical elevation for glacier climatic response Himalayan and karakoram glaciers hydrological balance Effects of climatic change on the water resources deriving from snow and ice melting and impacts on agriculture in some regions of the Karakoram (Pakistan, Asia) PROJECT WINNER AT THE CALL TOWARDS EXPO2015

24 Many thanks for your kind interest!

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