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Despite the importance of glacial lake development in ice dynamics and glacier thinning, in situ and satellite based measurements from lake-terminating glaciers are sparse in the Bhutan Himalaya, where a number of supraglacial lakes exist
. To better understand the influences of glacial lake formation and expansion on ice dynamics and glacier thinning, we acquired in situ and satellite based observations across lake- and land-terminating debris-covered glaciers in the Lunana region, Bhutan Himalaya. A repeat differential GPS survey reveals that thinning of the debris-covered ablation area of the lake-terminating Lugge Glacier for the 2004–2011 period (−4.67 ± 0.02 m a−1) is more than three times greater than that of the land-terminating Thorthormi Glacier (−1.40 ± 0.02 m a−1). The surface flow velocity decreases down-glacier along Thorthormi Glacier, whereas it increases from the upper part of ablation area to the terminus of Lugge Glacier. Numerical experiments with a two-dimensional ice flow model demonstrate that the rapid thinning of Lugge Glacier is driven primarily by a negative surface mass balance and that the dynamically induced change in ice thickness is small. However, the thinning of Thorthormi Glacier is suppressed by a longitudinally compressive flow regime. The magnitude of dynamic ice thickening more than offsets the glacier thinning, suggesting that over half of the negative surface mass balance is counterbalanced by the ice dynamics of Thorthormi Glacier. Multiple ponds on Thorthormi Glacier have been expanding since 2000 and merged into a single proglacial lake, with the glacier terminus detaching from its terminal moraine in 2011. Numerical experiments suggest that the speed up and thinning of Thorthormi Glacier will be accelerated with continued proglacial lake development
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The Hindu Kush Himalayan (HKH) region being seismically active and sensitive to climate change is prone to glacial lake outburst flood (GLOF)
. The Lemthang Tsho GLOF breached in the evening of 28 July 2015 innorth-western Bhutan is reminds of the looming threat, and stresses the need to have good risk management plan. The need to understand the physical processes in generating GLOF to is therefore imperative in order to effectively manage the associated risk. The paper therefore assesses the cause and impact of the Lemthang Tsho GLOF event using field and remote sensing data
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New reconnaissance data for a poorly characterized area in the western Bhutan Himalaya show distinction between the 40Ar/39Ar cooling age distributions of detrital minerals in the two river catchments of the Punatsang chu and the Wang chu
. Muscovites from five samples of Wang chu river sands yield ages (corresponding roughly to the time of bedrock cooling through a temperature of ca.350°C) between 9.37± 0.08 Ma and 13.98 ± 0.08 Ma. The majority of ages are less than 13 Ma, and the data for all samples have a unimodal distribution with an average age of ca. 11.4 ± 1.5 Ma. In contrast, muscovites from 14 Punatsang chu samples yield ages with nearly the same total range but with a distinctively multi-modal distribution. Two modes predominate in the Punatsang chu data: one at ca. 11.4 Ma, which is statistically indistinguishable from the single mode of the Wang chu data, and one at ca. 14.5 Ma. The full explanation for this distribution must await further bedrock and detrital dating studies, but one hypothesis is that the out-of-sequence Kakhtang thrust fault system - which is thought to transect the upper reaches of the river catchments - has juxtaposed two bedrock terrains with different cooling histories
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In high mountain regions, a number of natural catastrophes are related to glaciers, eg, outbursts of glacier-dammed lakes or interglacial water reservoirs, glaciers destroyed by volcanic eruptions, and various types of glacier surges
. But the glacier catastrophe in 2002 in the North Caucasus was a rare phenomenon resulting from a combination of a glacier surge and a high-speed ice-water-stone mudflow. The latter’s scale and particular nature makes it a unique phenomenon worldwide
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'Themes from Celebrating Mountain Women' contains extended abstracts of 39 papers given at a global gathering of mountain women that took place in Thimphu, Bhutan, from 1-4 October 2002 as part of the celebrations in the International Year of the Mountains
. The 'Thimphu Declaration' - a call to action on the issues in the lives of mountain women formulated at the end of the conference - is included as an annex. The points raised by the participants are focused on the topics of gender role and relations; natural resources and environment; health and well-being, entrepreneurship; and political, legal and human rights. The publication will be of interest to all those interested in mountain development in general and women's issues in particular, across the world
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Women all over the world must still fight to be accepted as equals, to have their values recognised as relevant, and to overcome the multiple burdens of home and employment
. Mountain women are further challenged, they belong to societies that are already marginalised and often cut off from the mainstream of society. In 2002, the International Year of Mountains, mountain women and men met together at a global gathering Celebrating Mountain Women (CMW), held in Bhutan, to celebrate the drive and spirit of mountain women, discuss the critical issues, and search for new ways forward. This publication summarises the background, discussions, findings, and outcomes of CMW. It is divided into three chapters followed by a bibliography. The first and last chapters describe the background and organisation, and the various materials produced and the way forward. The central chapter looks at the issues, research and policy needs, and recommended actions identified during the discussions on the five major themes: natural resources and the environment; health and well-being; entrepreneurship; legal, political, and human rights; and culture and indigenous knowledge
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