Influence of debris cover on glacier response to climate change: insights from Koxkar glacier using dynamic simulation
- PDF / 4,506,402 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 69 Downloads / 198 Views
ORIGINAL PAPER
Influence of debris cover on glacier response to climate change: insights from Koxkar glacier using dynamic simulation Wu Zhen 1 & Zhang Huiwen 2 & Liu Shiyin 3 & Chen Junyin 1 Received: 14 September 2017 / Accepted: 18 July 2019 # Saudi Society for Geosciences 2019
Abstract The response of debris-covered glaciers to climate change is more heterogeneous and complex than that of debris-free glaciers. The debris has a significant effect on glacier dynamic characteristics, which causes uneven mass balance changes, and then affects the change of glacier geometry evolves in response to climate. In our study, both energy balance and a two-dimensional mass and momentum conservation equation were used to simulate the ice temperature and velocity respectively at the main stream line of Koxkar glacier. The influence of the debris on ice temperature was described in the model. The ice velocity simulation was coupled with a description of ice viscosity under the influence of ice temperature. Our simulation results showed that the debris could increase the ice velocity and ablation in the middle of the glacier. Especially in the surface from 3200 to 3400 m.a.s.l, where the debris had great influence for ice velocity and temperature. From simulation results, we inferred that the ice thickness in this region would change obviously. Comparing with the measured thickness changes by ground-penetrating radar (GPR) between 1981 and 2008, the simulation result is consistent with measured results. Therefore, supraglacial lakes are easily developed in this region because of the high ice temperature and uneven ice surface. And the Landsat 8 remote-sensing image had verified this conclusion. Keywords Dynamic model . Koxkar glacier: debris cover . Ice temperature . Ice velocity
Introduction Debris on the glacier surface insulates ablation from atmospheric warming and complicates the response of the glacier to climate change compared with debris-free glaciers (Zhang et al. 2013b; Rowan et al. 2015). It is thought that debris has a significant effect on the mass balance changes because the effect of the debris either accelerates or suppresses ablation to the ice beneath the debris (Caidong and Sorteberg 2010; Liu and Liu 2015; Rowan et al. 2015). However, the response of Editorial handling: A. M. Al-Amri * Wu Zhen [email protected] 1
Lanzhou Institute of Seismology, Chinese earthquake Bureau, Lanzhou 730000, China
2
State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating, Gansu Desert Control Research Institute, Lanzhou 730070, China
3
The Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650091, China
the glacier with debris to climate has not been yet fully understood. The Tuomuer Mountain district is the largest glacierized area in Tian Shan, China, with a total of 629 glaciers covering an area of 3850 km2. A striking glaciological feature of this region is the development of many large dendritic valley glaciers (called Tuomuer-type valley glaciers by Chi
Data Loading...
