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Torrential rains, landslides, and seismic activity are the common factors that are causing unprecedented damage to life, property and infrastructure in Mandakini and Bhilangana basins of Garhwal Himalaya. Owing to such conditions, we demonstrate the feedback this landscape in Garhwal Himalaya in response to episodic tectonic uplift and monsoon precipitation. We calculated conventional geomorphic parameters to access the tectonic deformation across the major thrusts and faults. We further analyzed the normalized steepness index (Ksn), Chi (χ), and knickpoints along the longitudinal course of rivers. Additionally, the study attributed to active nature of Chail/Ramgarh thrust along the Balganga valley as envisaged by five levels of unpaired fluvial terraces, entrenched stream course, river ponding, active and stabilized landslide deposits, etc. Moreover, the flooding during the heavy rainfall events induced river toe cutting makes an effect on settlement over fluvial deposits. Therefore, we suggested that the highly dissected and tilted basins with deep V shaped valleys and ongoing seismicity also fabricates the region more vulnerable for hazards which threaten the human lives.

The present investigation is focused on imprint of tectonic perturbation along a major tributary, known as the Lastar Gad (Gad = River), in southeast catchment of the Mandakini river in Garhwal Himalaya. Based on morphotectonic studies across the watershed, we recognized evidences of neotectonics along the Jutogh/Munsiari Thrust (MT/MCT-II). Various geomorphic features, e.g., ponding of streams and formation of lakes, fluvio-lacustrine deposits, waterfalls, stabilized and active landslide fans, dissected hills, paired and unpaired terraces, fault scarps and offsetting of drainage pattern etc., point to the active tectonics. The field investigations are supported by computation of morphometric indices, such as, low values of Valley Floor Width to Valley Height (Vf), Asymmetry Factor (Af), elongated and tilted river basin with narrow valley floor as well as higher Bifurcation Ratio (Rb) and sinuosity parameters, immature topography and landscape, elongation and tilting of drainage basin and accelerated erosion-all show that the basin is structurally controlled. The uplift along the valley is further manifested by two significant indexes, e.g., Stream Length (SL) and Steepness Index (Ks). Also, the mud deposits, lacustrine flats and swampy and soggy land within the valley suggest the existence of an ancient lake basin, named as Gethina palaeolake, downstream of present day Badanital lake. The 14C AMS radiocarbon chronology of the Badanital lake core as well as Gethina-Jagtoli palaeolake profiles indicate the formation of these lakes around 5–6 ka BP due to tectonic upheaval along the MT. We assume that a huge landslide activity blocked the course of a small stream (Badani Gad), forming an ancient lake at Gethina locality, followed by deposition of a landslide fan on which was created the Badanital. Subsequently, the palaeolake basin was filled with sediments due to accelerated erosion from almost vertical hills in the catchment. Owing to this, the Gethina (ancient) lake was disappeared and the modern Badanital lake shrank to its present state.

Snout monitoring of the Gangotri glacier (Uttarakhand, India) during the ablation season (May to September) in years 2005 and 2015 by using rapid static and kinematic GPS survey reveals that the retreating rate has been comparatively more declined than shown by the earlier studies. Our study is based on the individual measurement by the remote sensing, added by the ground observations by using Differential global positioning system (DGPS) to determine the precise recession rate of the glacier at sub-centimeter level of accuracy. The GPS dataset show that the total average retreat along the snout has been 102.57 ± 0.05 m from 2005 to 2015 with an average rate as 10.26 ± 0.05 m/yr. Additionally, the shift in snout position was also measured through multi-temporal satellite data from 1989 to 2016. The results indicate that the Gangotri glacier snout has retreated by 585.62 ± 38.30 m during this period with an average retreat of 26.75 ± 4.36 m/yr from 1989 to 1999, 21.58 ± 3.77 m/yr from 1999 to 2009 and 14.60 ± 4.81 m/yr from 2009 to 2016. Such a decline in retreat is further confirmed by the satellite data set. A close examination of meltwater discharge and retreating rate (r2 = 0.95) show that both parameters are strongly correlated. Therefore, we suggest that a consistent decrease in meltwater discharge from 1999 to 2015 is in agreement with decreasing trend of retreating rate during the recent years. To determine the possible causes of decreased retreating rate, a relationship between debris thickness and melt rate was also established by ablation stakes. Further, we infer that the declining trend in the glacier retreat is not only controlled by prevailing weather conditions (rainfall and air temperature) but is also governed by increased debris cover on the glacier surface which prevents the ice to melt.

Tectonic reactivation along the major boundary thrusts and subsidiary thrust/faults in the Himalaya during the Quaternary period has resulted in the rejuvenation of the landforms. Considering, the role of neotectonic activity in the hazardous Kumaun region, we aim to study the neotectonically formed landscape along the Kulur River valley, a non glacier fed tributary of the Saryu River in the zone of the Berinag Thrust (BT). The field evidences encompassing a variety of geomorphic indicators, e.g., unpaired fluvial terraces, palaeo river channels, alluvial fans, active and stabilized landslides, lineaments, waterfalls, alignment of springs, deeply dissected hills, straight/meandering course of rivers/streams, V-shaped valleys, triangular fault facets and water logged/river ponding along with integrated values of eight morphometric parameters and Stream Steepness index (Ks) indices characterize the modification of landscape in the Kulur River valley. The computed morphometric parameters in the Kulur River drainage and its tributaries show that the basin has been tilted and uplifted forming V-shaped valleys along with deformed and disequilibrium longitudinal profile, thereof, suggesting it to be controlled by lithology and tectonics. Based on the response of active tectonics in form of geomorphic features and quantitative measurements of river channels, the entire basin has been divided into three segments in which the northern and southern segments are active compared to the middle sector. A possible NNE-SSW trending lineament/fault, running parallel to the Kulur River has been observed in the upper catchment and is characterized by fluvial terraces, river ponding and deflection and offsetting of drainage with rectangular pattern etc. This may have given rise to the widening and straightening of river courses which provide the favorable room for river ponding, resulting in deposition of about 2 m thick lacustrine mud deposit.

We present a stalagmite based high resolution climatic record between ∼4.0 and 1.9 ka BP from Dharamjali Cave in Pithoragarh (Kumaun Himalaya), an area which is influenced primarily by the Indian Summer Monsoon (ISM) and supplemented by the Indian Winter Monsoon (IWM). The chronology of the 41.5 cm long DH-1 stalagmite was constructed using a StalAge model on six 230Th/U dates. However, some samples have higher 232Th concentrations, leading to an increase in the final age uncertainties, hence the chronology supports only the possible climatic boundaries. However, the significance of this work lies in its being one of the rare studies of speleothems to reconstruct high resolution climatic changes in the NW India for the Upper Holocene. The δ18O values, ranging between −5.3‰ and −10‰, show a large variation, compared to the areas dominated by a single monsoon, and this can be ascribed to the two sources of moisture (e.g., ISM and IWM) in the study area during the Upper Holocene. The sample consists of aragonite except for two sections of calcite growth from 0–7.3 cm and 8.5–13.5 cm from the top. The climatic reconstruction, within the age uncertainties, indicates strengthened precipitation from 4.0 ka BP with a sharp drop (>−2‰) in δ18O values, peaking at ∼3.7 ka BP. A gradual decline in precipitation is observed from ∼3.7 to 3.0 ka BP with possible droughts, centered at ∼3.4, ∼3.2 and ∼3.0 ka BP. Subsequently, climatic amelioration took place between ∼3.0 and 2.9 ka BP, showing fluctuating trend in δ18O values with comparatively more rainfall, possibly generated by the IWM in the form of thunderstorms and hailstorms from ∼2.9 to 2.7 ka BP. Precipitation declined from ∼2.7 to 2.4 ka BP with a decadal scale major drought event, strongest in the present data set, at ∼2.5–2.4 ka BP, whereas, an abrupt drop in stalagmite δ18O values from ∼2.4 to 2.3 ka BP points to increased precipitation intensity. Thereafter, the precipitation gradually decreased until ca. 2.1 ka BP with one of the driest events at ∼2.1 ka BP. A century scale increasing trend in the precipitation intensity is observed from ∼2.1 to 2.0 ka BP, following which the precipitation again declined. Accordingly, five sudden drought events are documented, centering at ∼3.4, ∼3.2, ∼3.0, ∼2.5–2.4 and ∼2.1 ka BP. A gradual reduction in precipitation from ∼3.7 to 3.0 ka BP coincides with reduction and deurbanisation and step-wise disintegration of the Harappan civilization along the Indus-Ghaggar-Sarasvati valleys in the foreland areas of northwestern India.

This study is focused on a 3.55-m-long sediment core retrieved from Badanital (i.e. the BT core) in 2008. Badanital (30°29′50″N, 78°55′26″E, 2083 m a.s.l.) is a small lake located in the upper catchment area of the Ganges in Garhwal Himalaya, northern India. The lake and the regional broad-leaved semi-evergreen forests are under the influence of the Indian Summer Monsoon (ISM) and westerly associated cyclones. Palynological investigation of the BT core revealed past vegetation changes reflecting both climate and human impact during the last 4600 years. Maximum spread of oaks occurred during c. AD 550–1100 and c. AD 1400–1630, that is, the intervals which partly overlap with the ‘Medieval Warm Period’ and the ‘Little Ice Age’, respectively. Three intervals of decreased oak pollen percentages are attributed to (1) continuously drier and cooler climatic conditions and fire activity ( c. 2600–500 BC), (2) severe reduction in oak forests followed by secondary succession of alder woods ( c. AD 1150–1270) and (3) pre-modern settlement activities since the British imperial occupation (after c. AD 1700). We argue that the high percentages (i.e. up to 28%) of Humulus/ Cannabis type and Cannabis type pollen point to intense local retting of hemp c. 500 BC–AD 1050. Based on our age model, Cannabis fibre production at Badanital is contemporaneous with archaeological records of ancient hemp products from different parts of Eurasia suggesting possible linkages to early trade and knowledge exchange routes connecting India and the Himalaya with Central and East Asia and possibly Europe.

The aim of the present research is to provide the base line details of the NNW-SSE trending Raintoli fault (RF) which is running parallel to the North Almora Thrust (NAT) along the Saryu valley from Seraghat-Naichun to Seri in the central sector of the Uttarakhand Himalaya, India. The RF is characterized as dextral strike slip fault and behaves as a ductile shear zone within the zone of NAT. The dextral sense of shear movement of RF is delineated by the fabric of the shear zone rocks including microscopically observed indicators such as sigma and delta porphyroclasts, quartz c-axis, and the field structural data. Additionally, in the quaternary period the dextral strike slip fault is reactivated with oblique slip component as characterized by various geomorphic indicators, for example, triangular facets, abandoned river channels, unpaired fluvial terraces, and V-shaped valleys with recurrent seismicity. Further, the morphometric parameters including Valley Floor Width to Valley Height (Vf), asymmetry factor (AF), and gradient index (GI) further prove active nature of RF as suggested by low values of hypsometric integration, V-shaped valley, higher gradient index, and tilting of Saryu basin.

The present study documents the monsoon precipitation variability spanned ~ 2500 years, between 4.0 and 1.6 ka BP (before 1950 AD), from the Central Lesser Himalaya, India, using δ18O measurements of Tityana cave stalagmite (hereafter referred as TC1). At present, the cave receives precipitation from both Indian Summer Monsoon (ISM) and Western Disturbances (WDs). The δ18O variation between − 8.04 and − 10.46‰ through growth axis of the TC1 and five 14C AMS dates (due to large age uncertainty by 230Th/U method) have allowed us to identify the mid to late Holocene multi-decadal to centennial scale climatic oscillations. The higher δ18O values indicate the weakening of the monsoon precipitation, while the lighter values represent the stronger monsoon precipitation strength. Based on the fluctuations in δ18O values, three distinct phases of the precipitation variability are distinguished as, declined/decreased precipitation between ~ 4.0 and 3.4 ka BP with peak aridity around ~ 3.4 ka BP, followed by slightly improved conditions from ~ 3.4 to ~ 2.7 ka BP. Subsequently, the climate was reduced from ~ 2.7 ka BP onwards until the end of stalagmite growth, around ~ 1.6 ka BP with spikes of two major drought events centred at ~ 1.9 and ~ 1.6 ka BP. In general, the droughts, centred at ~ 3.4, ~ 1.9 and ~ 1.6 ka BP, are characterized by abrupt drop (from − 8.12 to − 8.04‰) in the δ18O values and point to the weakening of the monsoon. One of the major drought events at ~ 3.4 ka BP can be correlated with the collapse of the Indus valley civilization in the NW India. A close correspondence of the TC1 data set with other WDs influenced regimes likely indicates a relative impact of mid-latitude WDs after transition of the mid-late Holocene around 3.5–3.4 ka BP.

Investigated for d18O and d13C isotopes, mineralogy and growth rate, a 20 cm long and 230Th-dated calcite stalagmite from Kalakot (Jammu and Kashmir Himalaya), has recorded high resolution precipitation variability during the Pleistocene-Holocene transition. At present, the study area is influenced by both the Indian Summer Monsoon (ISM) and Westerlies. The StalAge model indicates that the stalagmite grew between 16.3 ka to 9.5 ka BP under the ideal isotopic equilibrium conditions as revealed by the Hendy test results. The d18O and d13C values range from -5.41 to -8.82% and -7.09 to -10.84% respectively. Although the U/Th chronology is poor due to low Uranium content in the samples resulting in relatively large errors, the first stalagmite inferred precipitation variability reconstructed from NW Indian Himalaya makes this study significant. The near footprints of three global events, e.g., Older Dryas (OD), Allerod period and Younger Drays (YD) can be noticed at ~14.3-13.9, 13.9-12.7 and 12.7-12.2 ka BP. The precipitation strength was weaker during the OD and YD, but was stronger during the Allerod interstadial. By the termination of YD interval, the climate seems fluctuating in the NW Himalaya. There seems variation in commencement, duration and termination of the above mentioned events in different parts of the globe due to latitude location and response time.