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Field observations provide authenticity in remote sensing studies when it comes to glacierized areas where weather conditions and terrain are not accessible. This study is an attempt to validate the relation between the Randolph Glacier Inventory (RGI) ice thickness and DEM through a field survey in the recently vacated area occupied by the moraine-dammed proglacial lake of the rapidly retreating Gepang-Gath glacier in the Lahaul Himalaya. We used Randolph Glacier Inventory (RGI) version-6 data of ice thickness for Gepang-Gath glacier with SRTM digital elevation model (DEM) of the year 2000 and Sentinel-1 Synthetic Aperture Radar (SAR) interferometry-based DEM of the year 2020 to calculate the lake depth. This relation is validated with ground-based investigation and lake bathymetry data collected using a kayak and metallic nob tied with rope and measuring tape in June 2021 where the maximum depth of the lake is 48 m. The SRTM-DEM profile and ice thickness data suggested that the Gepang-Gath glacial lake will expand ~2 km with a maximum depth of ± 10 m measured near the snout. As this lake is potentially vulnerable, this type of study will help measure lake depth using snout height and vice-versa with the help of DEM data to avoid hazards in feeding glaciers retreating.

Abstract The present study assesses trends in rainfall in Madhya Pradesh, Central India, over the long (1871–2016) as well as short (1987–2016) temporal scales. The region is home to disadvantageous groups of the population including vulnerable tribals who depend on rainfall-based agriculture and forest products. Therefore, any disruption in rainfall trends due to climate change needs to be documented for better planning. This study focuses on two meteorological subdivisions, East and West Madhya Pradesh, which receive a major portion of rainfall through the Bay of Bengal branch and the Arabian Sea branch of the Indian Summer Monsoon. The study is based on the rainfall series provided by the Indian Institute of Tropical Meteorology, Pune, India. This study used the Mann–Kendall test to detect a trend and Sen’s Slope to estimate the magnitude of change in rainfall. Statistically significant negative trends were detected in total annual (− 1.125 mm y − 1) and monsoon (− 1.242 mm y − 1) rainfall over long-term observation in East Madhya Pradesh only. However, during the last 30 years, no trends have been recorded in East Madhya Pradesh. In West Madhya Pradesh, rainfall has not recorded any trend for long- as well as short-term observation periods. The non-availability of a trend in rainfall during May and October at both meteorological subdivisions shows that there is no shift in the duration of the monsoon season over long as well as short temporal observations. The decreasing rainfall trends in Eastern Madhya Pradesh over the long-term observation seem to be caused by changing patterns of tropical cyclone frequency in the Bay of Bengal.

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 ΔELA (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.