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Understanding past glaciation and deglaciation is vital for assessing present-day glacier dynamics and response to climate change. We focus on reconstructing past glacier fluctuations in Lahaul, north-west India, a region located between arid Ladakh and the humid the Pir-Panjal range. We focus specifically on six glaciers in the Miyar and Thirot catchments of varying size, aspect and debris cover. To reconstruct past terminus fluctuations of these glaciers, we used repeat terrestrial photography and historical archives as data sets and mapped the terminus positions and latero-terminal moraines in the field along with glacier terminus mapping from high to medium resolution satellite images (e.g. Corona, Hexagon, Landsat and LISS IV). Results show that since the little ice age, all the studied glaciers have experienced terminus retreat and area loss, with average values of 1.46 and 0.9 km2, respectively. Precipitation data show a statistically significant decreasing trend during the last century with an increasing trend in annual average maximum (Tmax) and minimum (Tmin) temperature. This warming trend is more statistically significant for Tmin. Although total ice loss at the six studied glaciers is considerable (5.48 km2), this varies both spatially (i.e. from glacier to glacier) and temporally. We attribute this variability to topographic controls such as glacier hypsometry and another non-climatic factor, i.e. varying degree of debris cover. [ABSTRACT FROM AUTHOR]

The present study documents the long-term trends in the temperature and precipitation of a poorly represented region, the Sikkim, eastern Himalaya using the Mann–Kendall non-parametric test and the Sen's slope estimator. Additionally, the normal distribution curves and Cusum charts have been used to identify the shifts in extreme events and to detect the points of change in the climatic data series for robust analysis. The minimum temperatures recorded a positive trend in Gangtok (0.036 ˚C year−1 from 1961 to 2017) as well as in Tadong (0.065 ˚C year−1 from 1981 to 2010) stations, while the maximum temperatures showed no trend in Tadong station from 1981 to 2010 which is consistent with the trend in Gangtok station for the overlapped period. However, it was negative for the overall assessed period (− 0.027 ˚C year−1 from 1961 to 2017) in Gangtok. The average temperatures in Gangtok recorded no trend whereas a positive trend (0.035 ˚C year−1 from 1981 to 2010) was observed at Tadong station. A similar positive trend in the average temperatures has been detected at Gangtok also for the overlapped period. Accelerated warming was noticed during the last two decades with an increase in the probability of extreme events of temperatures (minimum, maximum, average) at the higher end. Precipitation was found to be more variable across the observed period and suggested no trend in the study area. [ABSTRACT FROM AUTHOR]