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Terrestrial cosmogenic nuclide (TCN) dating has emerged as one of the most useful techniques in the last two decades for quantifying geomorphological processes and building the chronology of late Quaternary glacial advances/retreats. The chronology based on TCN and optically stimulated luminescence (OSL) dating of glacial landforms from the northwestern (NW) Himalaya suggests that glaciers responded to a complex interaction between temperature and moisture essentially derived from either of the climate systems, the Indian Summer Monsoon (ISM) and the Mid‐latitude Westerlies (MLW). The discrepancies between the TCN ages obtained on moraine boulders/bedrock surfaces, and the OSL ages on the stratigraphically equivalent deposits, highlighted the need for a detailed investigation. The present study attempts to build the chronology of Quaternary glaciation events in the Karakoram and Ladakh Ranges using TCN dating of stratigraphically constrained moraine boulders and striated bedrock surfaces. The TCN ages from glacially eroded surfaces (GES) having prominent striations are narrowly clustered around the Marine Isotopic Stage‐2 (MIS‐2). Agreement between GES TCN ages and OSL ages on the stratigraphically equivalent moraines suggests negligible geological inheritance. The glacial advance during MIS‐2 can be attributed to the combined effect of reduction in north hemispheric insolation and enhanced westerly precipitation. However, relict non‐glacial surfaces and moraine boulders with minimal ice flow modifications yield wide age distributions, most likely suggesting denudational events (interglacials) and/or contribution from tributary valley flanks. Plain Language Summary: Quaternary glacial advances and retreats in the northwestern (NW) Himalaya respond to a complex interaction between climatic parameters, that is, temperature and moisture essentially derived from the two contrasting weather systems viz., the Indian Summer Monsoon (ISM) and the Mid‐latitude Westerlies (MLW). In this study, we employed terrestrial cosmogenic nuclide dating of stratigraphically constrained moraine boulders and striated bedrock surfaces to understand the dynamics of late Quaternary glaciation in the Karakoram and Ladakh ranges. The exposure ages obtained from glacially eroded surfaces (GES) show a narrow cluster around the Marine Isotopic Stage‐2 (MIS‐2), a period when the northern hemispheric insolation was low resulting in a temperature decline. The glacial advance during MIS‐2 is attributed to the combined effect of temperature reduction and enhanced westerly precipitation. Key Points: New insight into the Quaternary glacial history of NW Himalaya based on 40 10Be exposure ages of boulders and bedrock surfacesGlacially eroded surface ages suggest that Marine Isotopic Stage‐2 glacier advances were driven by enhanced westerlies and reduced insolationRelict non‐glacial surface/boulder ages indicate denudational events during the interstadial and/or contribution from tributary valleys [ABSTRACT FROM AUTHOR]

A flash flood that originated from Raunthi Gad-a tributary of the Rishi Ganga river, in Garhwal Himalaya, caused unprecedented loss to lives and damaged two hydropower projects on 7th Februray 2021. In order to asses the flood magnitude, the flow parameters of the flood were calculated using the super-elevation of the flood marks preserved in the flood affected valleys. The textural characteristics of the flood deposits in the upper reaches of the valleys indicate dominance of debris flows. The peak discharge upstream of the confluence of Rishi Ganga and Dhauli Ganga was around 1.1×105 m3/s, which was four order of magnitiude higher than the normal peak discharge (∼ 3 m3/s). The flow achieved a velocity of 30±3 m/s. An exponential reduction in the flow velocity (from ∼37 to 2 m/s) with distance is observed. For which the river gradient and increase in sediment load is implied flow that along its entrained way downstream between Raini and Tapovan. Considering the sensitivity of paraglacial zones to climate change, the paper calls for detailed studies pertaining to the response of paraglacial zones to extreme weather events. Importantly, it is necessary to have more hydrological data covering multiple valleys for predictive model simulation of the nature and magnitude of such disasters in future. [ABSTRACT FROM AUTHOR]

The relict intertidal deposits from the Kharod River Estuary, Gulf of Kachchh, and the distal end of Kori Creek are used to infer the Mid- to Late Holocene relative sea-level (RSL) change in western India. Employing sedimentology, geochemistry, palynology, ichnology, and optical and radiocarbon dating, the study suggests the dominance of fluvial activity between 16.5 ± 1.6 and 9.9 ± 0.7 ka. After ~7 ka (7.3 ± 0.4, 6.8 ± 0.5 ka), the sea level showed a positive tendency until 4.7 ± 0.2 ka. The tectonically corrected Mid-Holocene RSL change is estimated as 1.45 ± 0.33 m between ~7 and ~5 ka. The study suggests that the Mid-Holocene RSL high was due to the meltwater contribution from the Himalayan cryosphere, with subordinate contribution from glacio-isostatic adjustment and crustal subsidence. The Late Holocene tectonically corrected RSL change at ~1 ka (1.1 ± 0.1 ka and 1045 ± 175 cal yr BP) is estimated as 0.53 ± 0.43 m. This is ascribed to monsoon wind-driven tidal ingression that might have affected the tidal amplitude positively. The study suggests that the Mid-Holocene RSL change did not play a deterministic role in the abandonment of the Harappan coastal settlements. [ABSTRACT FROM AUTHOR]