Glacier shrinkage in the Himalayas under the monsoon climate

1. Glacier shrinkage in the Himalayas under the monsoon climate with the abundance of debris and dirt NAKAWO, Masayoshi National Institutes for the Humanities

2. Rikha Samba Glacier, Mukut Himal, Nepal AX010 Glacier, Shorong Himal, Nepal

3. Glacier surface lowering, m Massbalance of world glaciers RikhaSamba Glacier AX010 Glacier Yala Glacier Why the rate of shrinkage is so large in the Himalayas? ① The warming rate is large? ② Other reason? By Fujita

4. Tree Ring By Sano et al. The warming can be identified in the Himalayas, but the rate is not as pronounced, when compared with the rate at the other part of the world(roughly 0.7 to 0.8 degree/century), although the rate of glacier shrinkage is significantly large. Ice Core By Thompson et al.

5. Nepal Tibet Snow Fall probability, % Daily Precipitation, mm Daily Temperature, deg C OND JFM AMJ JAS Air Temperature, Deg C Observation of temperature and precipitation made at the Rikha Samba Glacier, Mukut Himal, Nepal By Fujita et al.

6. Monthly Precipitation, mm Comparison between glaciers fed during summer and winter, with the help of a glacier mass balance model, which takes into account the surface albedo. Summer accumulation Winter accumulation By Fujita et al.

7. Summer Type Winter Type Observation Elevation, m Mass Balance, mm If snow accumulates in winter, with completely the same total amount, the equilibrium line altitude becomes significantly higher, than glaciers fed during summer. By Fujita et al.

8. Surface Level, m OND JFM AMJ JAS Albedo Summer type Winter type Observation By Fujita et al. Summer snow keeps the surface albedo high so that the melting is hindered. This albedo effect is the major advantage of summer accumulation type glaciers located in the Himalayas.

9. Summary • The rapid shrinkage of glaciers in the Himalayas is not caused by a higher rate of warming but by 1) Precipitation: Snow　→　Rain ２）Albedo effect: high(snow) → low(ice) 3) Warming effect: → higher rate of ablation Therefore, the rapid shrinkage is caused by the fact that glaciers are fed during summer owing to the monsoon climate. Monsoon

10. Another possible cause for the rapid shrinkage of Himalayan Glaciers: Biological activities Yala Glacier, Langtang Himal, Nepal Yala Glacier, Lantang Himal

11. Cryoconite hole Formation of Cryoconite：　Wisdom of the creatures who decide to live on glaciers

12. Amount of dirt materials, dry weight, g/m2 Tibet Himalaya Patagonia Alaska Arctic By Takeuchi Third Pole region Great abundance of Cyanobacteria over Himalayan glaciers could have caused the rapid shrinkage.

13. Khumbu Himal, Nepal

14. Melt rate, m/a Distance from the terminus, m Melting of debris-covered ablation area, Khumbu Glacier Thick debris cover of 0.5 to 2 m or more Glacier ice, even under a thick debris cover, has melted at a rate of about 1 m/a as an average.

15. Debris covered large glaciers have also shrunk at a high rate in the Himalayas. Glacier surface lowering, m Massbalance of world glaciers RikhaSamba Glacier AX010 Glacier Yala Glacier Debris-covered glacier (Khumbu) Rapid deterioration of debris covered glaciers has lead to the formation of glacier lakes, and Glacier Outburst Flood with the failure of the dam bank.

16. With a warming experiment, Dongkemadi Glacier Winter type Change in annual balance, m Oerlemans’s estimation Summer type Annual Precipitation, mm Glaciers of summer accumulation type is more vulnerable to a warming climate than those of winter accumulation type. This is considered the main cause for the rapid shrinkage of Himalayan glaciers during the recent warming climate. By Fujita et al.

17. With further warming, glacier lake could form near the terminus of debris-covered glaciers. Elevation, m Distance along the flow direction, m By Naito et al.

18. Formation of cryoconite is one of the styles of the adaptation of the living creatures on glaciers Human beings decided to live on earth and acclimatized with the environment. We have triggered a rapid warming of global scale. Their wisdom, in association with the warming, Acceleration of glacier melt→Disappearance of glaciers Warming proceeds,→deterioration of environment They would lose their home →extinction！ Should we not be able to adapt, →extinction！