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Detailed field mapping of glacial and paraglacial landforms and optical dating from these landforms are used to reconstruct the early Holocene glaciation in the semi-arid region of Miyar basin, Lahaul Himalaya. The study identifies three stages of glaciation, of decreasing magnitude and termed, from oldest to youngest, the Miyar stage (MR-I), Khanjar stage (KH-II), and Menthosa advance (M-III). The oldest glacial stage (MR-I) has been established on the basis of detailed geomorphological evidence such as U-shaped valley morphology, trimlines, and truncated spurs. It is speculated to be older than the global Last Glacial Maximum (gLGM) based on the magnitude of DELA (Equilibrium-Line Altitude, 606m). No evidence of glacier expansion recorded from the basin correlates with the period of the gLGM. The second stage (KH-II) is well represented by extensive depositional features such as lateral and terminal moraines, drumlins, and lacustrine fills that have been constrained within 10 ± 1 to 6.6 ± 1.0 ka (Optically stimulated luminescence--OSL--ages), dating it to the early Holocene advance following the Younger Dryas cooling event. Exceptionally young glacial records of expansion are limited within a few hundred meters of the present termini of tributary glaciers and correlates with the 18th-century cooling event. Records of this glacial advance, termed the Menthosa advance, are clearly noticed in some tributary valleys. [ABSTRACT FROM AUTHOR]

The Indus River Basin (IRB), one of the major river basins in the Hindu Kush Himalaya, is primarily sustained by meltwater from the cryosphere. It caters to diverse sectors, including intense irrigation-supported agriculture, energy production, tourism and biodiversity. The cryosphere of the Upper Indus Basin (UIB) is mainly influenced by the western disturbances with subordinate contribution from the Indian Summer Monsoon. Increase in ambient temperature, shrinking cryospheric reserves, fluctuating surface run-off and enhanced frequency of extreme weather events are some of the noticeable indicators of climate change in the UIB. These changes will most likely adversely affect the water-dependent sectors in the upstream and downstream of IRB, posing serious threat to food security and livelihoods. Although the region has gained significant attention in recent years, there remains a noticeable knowledge gap pertaining to certain key issues with serious implications for the natural environment and the people. A national workshop was organized for stimulated deliberations to identify the major knowledge gaps and suggest a policy framework for climate change mitigation in the UIB. The workshop underscores the urgent need of multi-institutional, multidisciplinary, comprehensive, coordinated and time-bound collaboration to study the interplay of complex drivers on water resources of the UIB. [ABSTRACT FROM AUTHOR]

The present study is done in the Beas river (Manali to Mandi town) after the July 2023 flood to assess the geomorphic and geological vulnerability of the terrain and understand the role of human intervention in the disaster. The study is based on preliminary field observations and morphometric analysis that indicates that the surfaces proximal to the trunk riverbed and the ephemeral tributary channels suffered maximum damage. Along the upper Beas river, the lateral erosion caused by hyperconcentrated flows saturated with paraglacial sediments partly obstructed the river and also increased the erosivity that also led to remobilization of midchannel bars along with the uprooted trees. In the downstream (southern mountain front), maximum damage was caused by activating seemingly dormant ephemeral tributary channels. The slope-channel coupling locally bulked the sediment supply of the trunk river. The disaster was force amplified when the river was temporarily obstructed by the manmade structures (e.g., suspension bridges), and most importantly, urban settlements (largely hotels) on the flood plain. Also, many public buildings suffered as these were constructed in/along the ephemeral tributary channels, which were temporarily blocked by these structures, as well as by logged tree trunks. The Beas flood is yet another brutal reminder to change our perception towards the developmental approach, given that extreme events are projected to increase in the Himalaya. [ABSTRACT FROM AUTHOR]