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The Pamir region supplies water for most countries of the Central Asia. Discussions and arguments with regard to reduction of water resources related to climate change are popular today among various governmental and international institutions being a greatconcern for modern society. Probable decrease of the Pamirs runoff will affect downstreamcountries that can face water deficiency. However, there is no scientific rationale behindsuch disputes. The Pamir region is a remote, high-mountainous and hard-to-access area with scarce observation network and no reliable data. It is not sufficiently investigated in order to perform any assessment of climate change. This article represents results of study of climate parameters change (such as temperature, precipitation and river discharge) in the Pamirs. The study area covers all countries included in this mountain region (Tajikistan, China, Afghanistan and Kyrgyzstan). Observation records, remote sensing data and GIS modeling were used in the present work. Chronological data series were divided into two equal time intervals and were treated as climatic periods. Further analysis of climate change helped to estimate its influence on change of water potential in the Pamirs. The paper considers issues of liquid and solid precipitation change in the study area.

Tarim River basin is the largest endorheic river basin in China. Due to the extremely arid climate the water supply solely depends on water originating from the glacierised mountains with about 75% stemming from the transboundary Aksu River. The water demand is linked to anthropogenic (specifically agriculture) and natural ecosystems, both competing for water. Ongoing climate change significantly impacts the cryosphere. The mass balance of the glaciers in Aksu River basin was clearly negative since 1975. The discharge of the Aksu headwaters has been increasing over the last decades mainly due to the glacier contribution. The average glacier melt contribution to total runoff is 30–37% with an estimated glacier imbalance contribution of 8–16%. Modelling using future climate scenarios indicate a glacier area loss of at least 50% until 2100. River discharge will first increase concomitant with glacier shrinkage until about 2050, but likely decline thereafter. The irrigated area doubled in the Aksu region between the early 1990s and 2020, causing at least a doubling of water demand. The current water surplus is comparable to the glacial runoff. Hence, even if the water demand will not grow further in the future a significant water shortage can be expected with declining glacial runoff. However, with the further expansion of irrigated agriculture and related industries, the water demand is expected to even further increase. Both improved discharge projections and planning of efficient and sustainable water use are necessary for further socioeconomic development in the region along with the preservation of natural ecosystems.

The interaction between a glacier and its glacial lake plays an increasingly important role in glacier shrinkage and proglacial lake expansion, and it increases the risk of glacial lake outburst floods (GLOFs). Longbasaba Glacier is directly contacted by a moraine-dammed lake with a high outburst risk in the central Himalayas, and has drawn a great deal of attention from scientists and local governments. Based on Landsat images and in-situ measurements, the evolution records of the shrinkage of Longbasaba Glacier and the corresponding expansion of its proglacial lake were determined for 1988–2018, and the mass contributions of glacier shrinkage to the increase in lake water volume were assessed. During the past three decades, Longbasaba Glacier has experienced a continuous and accelerating recession in glacier area and length but accompanied by the decelerating surface lowing and ice flow. Consequently, Longbasaba Lake has expanded significantly at an accelerating rate. The glacier surface lowering played a predominant role in the mass contribution of glacier shrinkage to the increase in lake water volume, while ice avalanches were the main potential trigger for failure of moraine dams and subsequent GLOF events. Due to the areal expansion, decreasing mass contributions from parent glacier shrinkage, and some mitigation measures by local governments to improve the drainage systems, the potential risk of outburst for Longbasaba Lake has continuously decreased during the last decade.

This study was partially supported by core funds of ICIMOD contributed by the governments of Afghanistan, Australia, Austria, Bangladesh, Bhutan, China, India, Myanmar, Nepal, Norway, Pakistan, Sweden, and Switzerland. AO was supported by funding from the National Environmental Research Council (NERC) National Capability Overseas Development Assistance under the grant 'Polar expertise –Supporting development' (NE/R000107/1). ; River systems originating from the Upper Indus Basin (UIB) are dominated by runoff from snow and glacier melt and summer monsoonal rainfall. These water resources are highly stressed as huge populations of people living in this region depend on them, including for agriculture, domestic use, and energy production. Projections suggest that the UIB region will be affected by considerable (yet poorly quantified) changes to the seasonality and composition of runoff in the future, which are likely to have considerable impacts on these supplies. Given how directly and indirectly communities and ecosystems are dependent on these resources and the growing pressure on them due to ever-increasing demands, the impacts of climate change pose considerable adaptation challenges. The strong linkages between hydroclimate, cryosphere, water resources, and human activities within the UIB suggest that a multi- and inter-disciplinary research approach integrating the social and natural/environmental sciences is critical for successful adaptation to ongoing and future hydrological and climate change. Here we use a horizon scanning technique to identify the Top 100 questions related to the most pressing knowledge gaps and research priorities in social and natural sciences on climate change and water in the UIB. These questions are on the margins of current thinking and investigation and are clustered into 14 themes, covering three overarching topics of 'governance, policy, and sustainable solutions', 'socioeconomic processes and livelihoods', and 'integrated Earth System processes'. Raising awareness of these ...