Articles | Volume 5, issue 3
The Cryosphere, 5, 539–549, 2011
The Cryosphere, 5, 539–549, 2011

Research article 11 Jul 2011

Research article | 11 Jul 2011

Favorable climatic regime for maintaining the present-day geometry of the Gregoriev Glacier, Inner Tien Shan

K. Fujita1, N. Takeuchi2, S. A. Nikitin3, A. B. Surazakov4, S. Okamoto1, V. B. Aizen4, and J. Kubota5 K. Fujita et al.
  • 1Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
  • 2Graduate School of Science, Chiba University, Chiba, Japan
  • 3Department of Glacio-Climatology, Tomsk State University, Tomsk, Russia
  • 4College of Science, University of Idaho, Moscow, Idaho, USA
  • 5Research Institute for Humanity and Nature, Kyoto, Japan

Abstract. We conducted 2 yr (2005–2007) of in situ meteorological and glaciological observations on the Gregoriev Glacier, a flat-top glacier within the Inner Tien Shan, Kyrgyzstan. Relative carrier-phase GPS surveys reveal a vertical lowering at the summit of the glacier. Based on snow density data and an energy-mass balance model, we estimate that the annual precipitation and summer mean temperature required to maintain the glacier in the current state are 289 mm and −3.8 °C at the glacier summit (4600 m a.s.l.), respectively. The good agreement between dynamically derived precipitation and the long-term observed precipitation at a nearby station in the Tien Shan (296 mm at 3614 m a.s.l. for the period 1930–2002) suggests that the glacier has been in a near steady-state in terms of mass supply. The glacier mass-balance, reconstructed based on meteorological data from the Tien Shan station for the past 80 yr, explains the observed fluctuations in glacier extent, particularly the negative mass balance in the 1990s.