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The present study elucidates velocity of the Indian plate from 2013 to 2016 with the help of six continuously operating permanent Global Positioning System (GPS) stations and tracks the crustal motion and direction directly by means of space-based geodetic measurements. The GPS derived velocity estimates were computed with respect to 2008 International Terrestrial Reference Frame (ITRF 08) and carried out almost all along the arc in the Indian Himalayan Region (IHR). The velocity vectors indicate that the Indian plate is moving towards the NE direction (average velocity of 46.95 ± 0.23 mm/yr) with higher movement towards the eastward direction (36.11 ± 0.17 mm/yr) compared to the northward direction (29.02 ± 0.16 mm/yr). Variations in the plate motion between IISC and permanent GPS stations suggest that presently, the convergence rate is about 8.06 ± 0.28 mm/yr and 5.71 ± 0.17 mm/yr for Higher Himalaya and Lesser Himalaya respectively. In addition, the deformation rate was also calculated on the basis of baseline shortening between IGS stations (IISC and LHAZ) and permanent GPS stations. The results suggest that the deformation is about 11.68 ± 1.32 mm/yr above the Main Central Thrust (MCT) and 6.74 ± 1.20 mm/yr above the Main Boundary Thrust (MBT) with respect to the Indian plate (IISC), while it is 20.60 ± 1.76 mm/yr above the MCT and 11.42 ± 1.21 mm/yr above the MBT with respect to Eurasian plate (LHAZ). The strain rate through GPS measurement reveals that the maximum strain is accumulated in the central part of the Himalaya between the MBT and MCT, indicating vulnerability of the central Indian Himalaya for future earthquakes. [ABSTRACT FROM AUTHOR]

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 (V f), Asymmetry Factor (Af), elongated and tilted river basin with narrow valley floor as well as higher Bifurcation Ratio (R b) 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 (K s). 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. [ABSTRACT FROM AUTHOR]

This study aims at assessing the tectonic and climatic responses to landscape changes transpired in the Durung Drung basin in the Zanskar Himalaya. We used relevant geomorphic indices interpreted from ASTER DEM satellite data and supplemented by the field observations to decipher active tectonics and resultant changes in the landscape. A N-S trending fault in the north of the basin was studied with the help of basin geometry which includes relative parameter, length area relation, form factor, shape factor ratio, elongation ratio, circulatory ratio, compactness coefficient and morphotectonic indices (e.g., drainage basin asymmetry, mountain front sinuosity, hypsometric integral, topographic symmetric factor) to comprehend the geomorphic signatures of the active tectonics. The geomorphic indices indicate upliftment and tilting of the basin. The data on mountain front index and hypsometric integral reveal the uplift and high relief. We propose that the western side of the basin is tectonically more active than eastern side, suggesting active upliftment. The convex nature of hypsometric curve and strongly elongated circulatory ratio reflect competing role of deformation by tectonics. The results of mountain front index and hypsometric integral reveal high relief and uplift. Overall deglaciation of 12.91% was observed in the basin. Analysis of the meteorological data for the last century (1901–2017) indicate that increase in minimum and maximum temperature coupled with increase in liquid precipitation are probably the main drivers of glacier depletion. We conclude that the drainage system of this basin is structurally controlled and overall landscape change is significantly influenced by the ongoing perturbations in the climate system. [ABSTRACT FROM AUTHOR]

Although the variations in δ 18 O and δ 13 C and the U/Th dating in the speleothems are considered as key proxies, improved dating with better quality resolution as well as composition of stalagmites and growth rate along with the cave monitoring are equally important for understanding the high resolution precipitation variability in the past. With a total of six dates on a 11.5 cm long stalagmite, we re-interpret the decadal to century scale climatic changes with multi-year droughts from the Indian Central Himalaya between ca. 1622 and 1950 AD. The sample is composed of aragonite (both compact sub-layers and porous sub-layers). Although, the age model of this young speleothem may be within age uncertainty owing to the high 230 Th/ 23 2 Th isotope ratios, yet the distinction of this study lies in recording various historical drought events which are otherwise never reported from the Himalayan foothills. Additionally, the sample consists of reasonable amount of U (>2 ppm), thus the age correction requirement may be minimum. The higher growth rate and comparatively lower values of δ 18 O and δ 13 C are observed during the Little Ice Age (LIA) until ca. 1820 AD, indicating its being wet in the Himalayan foothills in contrast to the Peninsular India and other regions which are solely influenced by the Indian Summer Monsoon (ISM). This is mainly because the monsoon trough moves from the plains to the Himalayan foothills during break-monsoon conditions and provides more orographic precipitation in form of the Westerlies in the south facing Himalayan slopes. The post-LIA period from ca. 1820 AD onwards is interpreted as comparatively drier than the LIA. [ABSTRACT FROM AUTHOR]

A 6 m thick varvite profile exposed at Bharatpur (77° 27′ E: 32° 48′ N, altitude 4692 m) in the NW Himalaya was investigated to understand the past climatic signatures during the Late Quaternary period. The radiocarbon chronology brackets the varvite sedimentation between ∼24.3 and 7.2 ka BP and the sedimentary sequence is bounded by river born gravel at the top and glacial outwash at the bottom. The proxies used were lithology, chronology (AMS/radiocarbon dating), geochemical analysis, loss on ignition (LOI), and mineral magnetism. Other parameters, e.g., Chemical Index of Alteration (CIA), Chemical Index of Weathering (CIW), Al 2 O 3 /SiO 2 , Fe 2 O 3 , CaO, MgO and Al/Na ratio were also used. Based on the combined data set, six phases of warm and cold climatic conditions are reconstructed. The mean CIA, CIW and Al/Na ratios reveal that the sediments were incorporated from sedimentary rocks by moderate silicate chemical weathering process. Based on the available chronology, the basal most glacial outwash event can be estimated as ca. 24.3 ka BP and the laminated section shows continuity of sedimentation from the Late Quaternary to Holocene. The period between ∼ ca. 24.3 and 22.6 ka can be regarded as an arid phase. From ∼ ca. 22.6–20.5 ka BP, a slight increase in monsoonal precipitation is observed, followed by decreased precipitation from ∼ca. 20.5 to 18 ka BP. The period from ca. ∼18 to 15.7 reveals warm and humid climatic conditions. We suggest that a cold event from ca. ∼15.7 to 11.5 may correspond to the Younger Dryas (YD) which in turn is followed by a phase of maximum moisture of the Holocene Climate Optimum (HCO) (ca. ∼11.5–7.2 ka BP) in the study area. The increased CIA during deglaciation and HCO suggest high chemical weathering, whereas, the LGM (Last Glacial Maximum) and YD are represented by the low CIA. The observed climatic phases/events are in agreement with the records from other parts of the Himalaya. [ABSTRACT FROM AUTHOR]

This study provides evidence of the monsoon record over the past 25 ka from the Kilang Sarai palaeolake which is located in NW Himalaya in the rain shadow zone of the Indian Summer Monsoon (ISM). The multi-proxy study by using geomorphology, carbon isotopes, mineral magnetism, clay mineralogy and elemental chemistry of a 8 m thick laminated lacustrine sediments indicates that the area experienced fluctuating precipitation conditions during the last 25 ka. The time period between 12 and 5 ka BP can be regarded as a very wet interval of the Last Glacial to mid Holocene due to a combined effect of ISM and Westerlies, followed by aridity after 5 ka BP. Tectonic triggers may have caused the development of terraces and closure of lake. At the millennial time scale, a correlation of precipitation and vegetational changes between our data and other records from similar geographical settings suggests that Kilang Sarai basin responded to periods of strengthening in precipitation during the Last Glacial to early Holocene. [ABSTRACT FROM AUTHOR]

We report the first high resolution stalagmite record from Indian Central Himalaya by using a combined oxygen and carbon isotopic study spanning the last 4000 years. In addition to the multi-decadal events, the stalagmite data also provide information on the variability in the intensity of precipitation [Indian Summer Monsoon (ISM) and Westerlies] in north Indian hills during the Late Holocene. The δ 18 O values show strong variability between −2.1‰ and −8.9‰. The extremely high variability points to the monsoon from two different sources compared to other similar aged caves which are primarily controlled by one monsoon, such as the East Asian Summer Monsoon (EASM; although ISM has penetrated into some parts in the areas of EASM in the past) or the Westerlies. Therefore, we suggest that the Westerlies played an important role in the Late Holocene climate of the Indian Himalaya. As the source of the Westerlies is Mediterranean/Atlantic, the North Atlantic Oscillation (NAO) which was responsible for comparatively stronger Westerlies in southern Europe, may have brought higher precipitation to the north Indian hills. The stronger Westerlies may also have resulted in the highest precipitation between 0.5 and 0.25 ka BP (1450–1700 AD; a part of the LIA) in contrast to the weakening of the Indian Summer Monsoon (ISM) in peninsular India. The stalagmite has also recorded the driest period, peaking at ∼3.2 ka BP which may be nearly synchronous with the final collapse of the Harappan culture in northwest India. [ABSTRACT FROM AUTHOR]

Abstract: Stable isotopes from a U/Th dated aragonite stalagmite from the Central Kumaun Himalaya provide evidence of variation in climatic conditions in the last ∼1800 years. The δ18O and δ13C values vary from −4.3‰ to −7.6‰ and −3.4‰ to −9.1‰ respectively, although the stalagmite was not grown in isotopic equilibrium with cave drip water, a clear palaeoclimatic signal in stalagmite δ18O values is evident based on the regional climate data. The stalagmite showed a rapid growth rate during 830–910 AD, most likely the lower part of Medieval Warm Period (MWP), and 1600–1640 AD, the middle part of Little Ice Age (LIA). Two distinct phases of reduced precipitation are marked by a 2‰ shift in δ18O values towards the end of MWP (∼1080–1160 AD) and after its termination from ∼1210 to 1440 AD. The LIA (∼1440–1880 AD) is represented by sub-tropical climate similar to modern conditions, whereas the post-LIA was comparatively drier. The Inter Tropical Convergence Zone (ITCZ) was located over the cave location during wetter/warmer conditions. When it shifted southward, precipitation over the study area decreased. A prominent drop in δ18O and δ13C values during the post-LIA period may also have been additionally influenced by anthropogenic activity in the area. [Copyright &y& Elsevier]

Abstract: Many noteworthy properties of climate recorded by stalagmites can result from their mineralogy and fabric as well as their mode of occurrence. In this study, X-ray diffraction (XRD) and Scanning electron microscope (SEM) investigations were carried out for a well laminated stalagmite from Chulerasim cave, north India, to identify the mineral composition and structure of the laminae. As some early reported stalagmite laminae from Thailand and Southwestern China, the laminae of this stalagmite are composed of alternating compact and porous sub-layers. The XRD results confirm that the stalagmite is composed mainly of primary aragonite, which corrects the previous interpretation. The SEM results show that the compact sub-layer is composed of elongated columnar aragonites with a general longitudinal orientation (parallel to the vertical growth axis) and the coalescence of the aragonite crystals is well developed, leaving few inter-crystalline voids. The compact sub-layer may have formed in quasi-equilibrium conditions and provides the main carrier of climate proxies. The porous sub-layer is made up of needles, drusy and fibrous aragonites intersecting each other. Accordingly, the coalescence is low, with many inter-crystalline voids, which suggests a short hiatus between two adjacent compact sub-layers. Therefore, the growth of alternation of compact/porous sub-layers may not be successive, and they may have formed in different seasons. The results suggest that, for stalagmite/palaeoclimate research, cave monitoring should be performed to reveal when and how the compact sub-layers were formed. [Copyright &y& Elsevier]

Abstract: This paper presents the first stable isotope (δ18O and δ13C) data of a ∼400 years (1590–2006 AD) long annual to decadal-resolution speleothem record collected from the Indian Lesser Himalaya. The data show a variation from −2.7 to −5.9‰ in δ18O and −5.3 to −8.8‰ in δ13C. The isotopic analyses indicate that the climate during this period can be divided into two stages: a wet phase during the Little Ice Age (LIA) (1590–1850 AD) and comparatively dry phase during the post-LIA after 1850 AD. However, the record also documents the minor dry events during the LIA and a wet episode after the LIA. Within the age uncertainty, the dry spells during the LIA are linked with the historical drought events in the Indian subcontinent and similar latitudes. The isotopic record is consistent with a number of previous studies in the areas influenced by the Westerlies but appears to be conflicting to the regions, dominated by the Indian Summer Monsoon (ISM). This may be due to the possible changes in the strength of Westerlies in the study area and added by negative anomaly of North Atlantic Oscillation (NAO) during the LIA. [Copyright &y& Elsevier]

Abstract: An event of neotectonic activity on an NE–SW trending subsidiary fault in the zone of E–W running intracrustal boundary thrust (South Almora Thrust) in the Champawat district of eastern Kumaun Himalaya resulted in creation of a lake at ca. 21.5BP. The lake drained in the late Holocene, leaving behind a 5.0m thick sedimentary sequence of mostly black and carbonaceous mud, with a minor magnetic reversal between 20.5 and 19.7kaBP at the base. The profile, studied by using multi-proxies (e.g., carbon isotopes, pollen analysis, palaeo and mineral magnetism and clay minerals) has recorded globally well established abrupt climatic events in the last 20,000 years, such as the LGM, Older Dryas (OD), Younger Dryas (YD), Holocene warming, 8.2ka, and 4.2ka events. Most events, estimated assuming a constant rate of sediment accumulation for similar lithologies, may be related to the rapid changes in the local climate and albedo structure. The ITCZ may have played a key role in controlling the behavior of the southwest monsoon from the LGM. [Copyright &y& Elsevier]

Abstract: The youngest fossil Golunda (Rodentia, Muridae) is described from the Late Pleistocene fluvio-lacustrine deposits, exposed at Dulam (Bageshwar), Kumaun Lesser Himalaya, India. The age of fossiliferrous horizon is estimated as 31,000 yr BP. A new species, Golunda dulamensis nov. sp. has highly derived characters, e.g., antero-posteriorly stretched molars, upper molars with more length and less width, stephanodonty, cusps in M3 strongly inclined backward giving the molars a very stretched aspect, and metaconid and entoconid in M3 forming almost straight lingual row of the cusps. G. dulamensis nov. sp. is most similar to present day G. ellioti but differs from the later slightly by larger size, a thin connection between t4 and t5 in M1, and comparatively larger entoconid and very weakly developed antero-labial cusp in M3. We suggest that highly specialized molars of G. dulamensis nov. sp. and present day G. ellioti are derivable through G. kelleri. We also propose that Golunda migrated from Asia to Africa, not from Africa to Asia as was thought by earlier workers. [Copyright &y& Elsevier]

The intraplate Kachchh Rift basin has been hit by several devastating earthquakes in the historic past including the 1819 Allah Bund Earthquake and the 2001 Bhuj earthquake. The source region of these earthquakes, within the basin have been studied by several workers in the last two decades to understand their potential for earthquake recurrence. However, very little information is available on the palaeoseismic and geomorphic characterization of Kachchh Mainland Fault (KMF). Therefore, in the present study, six trenches were excavated across the KMF, between Lakhpat and Nirona to understand ground deformation pattern and timing of the historic earthquakes. Based on geomorphic and palaeoseismic investigations, five palaeoearthquakes of Early to Late Holocene have been identified between 10,000–890 yrs. Apart from the Holocene, an earthquake of Late Quaternary period was also identified, which possibly occurred around 19,800 yrs BP. Fault related parameters were analyzed to understand the geometry of the active fault scarp along KMF. The results of the analyzed fault geometric parameters show that the vertical displacement along the KMF is higher than the horizontal displacement. The slip rate of the KMF from the western portion to the middle portion decreases from 0.08 to 0.04 mm/yr, and increases towards east from 0.22 mm/yr to 0.36 mm/yr. As the Kachchh district of the Gujarat state is rapidly developing in terms of infrastructural development, the outcome of this research might provide significant inputs for micro zonation studies and also in the evaluation of the seismic hazard in the Kachchh region. [ABSTRACT FROM AUTHOR]

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 (K sn), 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. [ABSTRACT FROM AUTHOR]

Since 2002, Gravity Recovery and Climate Experiment (GRACE) satellite has provided monthly estimates of land water storage variations by monitoring time-variable components of earth's gravity field. We present GRACE satellite RL05 gravity data at 1° × 1° resolution to estimate terrestrial water storage change (surface water + groundwater) over India during Indian Summer Monsoon (ISM) and Northeast (NE) monsoon periods for the year 2015. As the NE monsoon was above normal in 2015, groundwater storage has increased significantly. By using GLDAS2.1 (1° × 1° resolution data) land surface state variables, we deduced as to how Terrestrial Water Storage (TWS) is partitioned into canopy water and soil moisture components. By computing storage changes in GRACE TWS, Global Land Data Assimilation System (GLDAS) land surface state variables and by using a terrestrial-based water balance approach, we calculated changes in the groundwater storage. The GRACE data indicate the variation of 15 cm in the TWS during the ISM period over India and a gain of 2.35 cm NE season over Peninsular India. After the ISM season, the groundwater storage was increased by 13 cm over India and 6.45 cm during the NE monsoon over Peninsular India. We also observed a high run-off (sub-surface + surface) rate in both the monsoon periods. The accumulated rainfall over India was estimated as 76.58 cm out of which 33.8 cm was computed as run-off (ISM season). Similarly, the mean rainfall in Peninsu lar India was calculated as 8 cm out of which 3.86 cm was approximated as run-off (NE monsoon season). [ABSTRACT FROM AUTHOR]

In general the genesis of the Kashmir basin is being viewed as a result of compressional tectonics, perhaps because of the reason that the basin is located in India-Eurasia convergence zone. However, there is no work that convincingly demonstrates how existing geomorphic architecture of the Kashmir basin evolved due to thrust tectonics? With answer to many questions Alam et al., (2015) proposed an extensional model for the development of the Kashmir basin. Moreover, based on deformation styles at varied spatial scales Alam et al., (2017) also suggested the co-existence of dominant extensional and relatively feeble compressional deformations within the basin. Shah (2017) just on the basis of deliberate misinterpretations, recycling of copied text, unrealistic one dimensional cartoons, and as always not for scientific reasons expresses disagreement with Alam et al., (2017). Thus, while responding to the bafflement of Shah (2017), we throw further light on hybrid tectonic character of the Kashmir basin. [ABSTRACT FROM AUTHOR]

This paper presents a new interpretation of overlapping differential deformations and likely causes of the structural heterogeneity within the Kashmir basin. Representing a prominent and distinctive strain feature in NW Himalaya, the broad geomorphic expression of the Kashmir as an elongated NW-SE trending sedimentary trough is inconsistent with general compression governing structural trend and deformation pattern of ∼2500 km long Himalayan Frontal Thrust zone. In addition to the general extensional geometry, there are prominent anomalous deformation features at varied spatial scales in the basins that imply dominance of extensional tectonics. We infer that contrary to the overall compression dominant mechanism of the Himalaya, the apparent extensional geometry of the basin connotes orogen-parallel extensional deformation (pull-apart), triggered by oblique convergence in the NW Himalaya. Moreover, we construe that the comparatively younger contractile (positive) features in form of the geomorphic convexity (push-up), accompanied by out-of-sequence reverse faulting (Balapur Fault, hereafter called as BF) within the basin which is generally believed to be associated with the uplift along NE dipping southern thrust complex (MBT/MCT), possibly resulted due to the tectonic reversal (positive inversion). The presence of the compressional features within the locally predominant extensional setting is suggestive of the basin's hybrid character—where variable tectonic regimes (earlier extension and subsequent compression) seem to be coexistent. [ABSTRACT FROM AUTHOR]

The consequence of strain accumulation along various Himalayan thrusts is manifested in shaping the topography and present day lanscape features of the Himalaya. Consequently, the strain accomodation is attributed to the occurrence of various devastating earthquakes in the Himalayan domain including 1905 Kangra earthquake (Mw 7.8) which occurred along the Kangra valley fault. In the present study, we analyzed and estimatedsss fault related parameters, gradient-length anomaly (GLA) analysis together with Interferometric Synthetic Aperture Radar (In-SAR) measurements to understand the landscape evolution and deformation pattern within the Soan dun (piggy back basin) in the northwest Himalayan front. We combined the results of geodetic, geological, geomorphology and InSAR to constrain the uplift and subsidence between Himalayan Frontal Thrust (HFT) and Main Boundary Thrust (MBT) zones. The estimated results of fault parameters reveal that the horizontal shortening of northwest Himalaya is higher than the vertical uplift. The computed values of GLA magnitude analysis for the uplifted region vary from −9.21 to −0.77, whereas these range from 5.48 to 26.60 for the subsided region. The depicted range of vertical deformation observed from the InSAR measurements ranges from −3.13 to +3.14 mm/y, where the positive and negative value of phases are correlated with the ground uplift and subsidence. The rate of deformation observed from Persistent Scatterer Interferometry (PSI) phase velocity and GLA magnitude is positively supported by the chronologically constrained uplift rates as 3.4 ± 0.3 mm/y. The geomorphic evidences such as folded, tilted and truncated alluvial fan surfaces, offsetting of channels, fault scarps and displaced sedimentary sequences indicate active nature of the Soan dun. The study would be eventually useful for seismic hazard assessment and future infrastructure development in the seismotectonically active regions like Soan dun of NW Himalayan front. [ABSTRACT FROM AUTHOR]

This study represents the first attempt to examine spatial and seasonal variations of the surface water budget by using the Gravity Recovery and Climate Experiment (GRACE) by measuring gravity anomalies on earth to estimate changes in Total Water Storage (TWS) content over the north-western region of the India including New Delhi and states of Rajasthan, Uttar Pradesh and Haryana, covering an area of 676,917 km 2 . The TWS (surface plus ground) and its changes were estimated from 2003 to 2012. Additionally, Global Land Data Assimilation System (GLDAS) variables were used to infer as to how TWS was partitioned into canopy water and soil moisture components. To evaluate monthly accumulated rainfall, Tropical Rainfall Measuring Mission (TRMM) data, processed by the Global Precipitation Climatology Center (GPCC) were used. By computing storage changes in GRACE, TWS, GLDAS land surface state variables and terrestrial-based water balance approach, we calculated groundwater storage changes. The time-series comparisons show good agreement between the GRACE satellite data, GLDAS model data and computed groundwater data. The change in soil moisture storage is less than that in saturated storage. Both the GRACE and calculated groundwater storage changes indicate storage loss in the range of 86.43 km 3 /y ± average of 10 years data (in terms of equivalent water thickness). The average groundwater loss for was calculated as 9.7 ± km 3 /y, states of Haryana as 9.7 ± km 3 /y, Rajasthan as 33.199 ± km 3 /y and Uttar Pradesh as 44.4827 ± km 3 /y. Our results are convincing of a credible GRACE hydrology data which can be handy in monitoring storage dynamics and water availability at regional scale. As GRACE data are available for virtually every region of the world, their application in conjunction with hydrological models will improve applications of hydrological studies which may lead not only to water balance closures, but also to sustainable water resource management at regional scale. [ABSTRACT FROM AUTHOR]

A multi-proxy study involving phytoliths, diatoms, thecamoebians and sponge spicules was carried out on a trench profile (260 cm deep) from Karela Lake in the Central Ganga Plain to reconstruct climatic variations since ca. 17,000 cal BP. The testate amoebae record indicate spells of winter monsoon between ca. 17,000 cal BP and 13,700 cal BP. Increased diversity of diatoms, testate amoebae and sponge spicules, in addition to low Humidity/Aridity Index (Iph) values suggest strengthened monsoon inducing the expansion of lake margin and high primary productivity during ca. 13,700 to 4300 cal BP. Further between ca. 4300 and 2900 cal BP, higher Iph values and related responses of other studied proxies show a stressed lake ecosystem. Since ca. 2900 cal BP, area of the lake was reduced responding to low intensity of the Indian Summer Monsoon. Anthropogenic activities may also have played a role in the lake shrinking at least during some parts of this duration. [ABSTRACT FROM AUTHOR]

Agriculture is a major contributor to the economic development of modern as well as ancient India and largely depends on the rainfall in the monsoon season. In order to understand the impact of climate variability on cultural changes in the Indian subcontinent, high resolution centennial to millennial scale middle Holocene Indian summer monsoon (ISM) variability was reconstructed from Bednikund lake, located in an alpine meadow of the Pindar basin, Chamoli, Central Himalaya. Increased ISM precipitations were found during ∼5930-3950 (mid-Holocene climate optimum), ∼3380–2830 (Minoan Warm Period), ∼2610–1860 (Roman Warm Period), ∼1050–760 (Medieval Climate Anomaly), and ∼320 cal yr BP to Present (Current Warm Period). The decreased ISM strengths were found during ∼3950-3380, ∼2830–2610, ∼1860–1050 (Dark Ages Cold Period), ∼760–580, and ∼500-320 cal yr BP (Little Ice Age). The covariance between our records of precipitation change and total solar irradiance for the middle to late Holocene and with Northern hemisphere (NH) temperature for the past two millennia suggested solar insolation as a primary forcing mechanism of ISM variability. The reconstructed paleoclimate combined with archaeology and historical records indicated that ancient Indian civilizations e.g., the Indus Valley (∼5200-3300 cal yr BP) and Vedic (∼3400-2400 cal yr BP) had established and thrived during periods of strengthened ISM precipitation, whereas their collapse closely corresponded to the decreased strength in ISM. From ∼2400 to 200 cal yr BP, the Indian subcontinent witnessed the rise and fall of various Kingdoms/dynasties. This period saw an exponential expansion/growth in agriculture, economy, population, languages, architecture, and religions in the Indian subcontinent. The agrarian-based economy showed little or no impact of monsoon weakening after ∼2400 cal yr BP possibly due to development and reforms in administrative policies, construction of irrigation systems such as dams, lakes and canals, use of technology for irrigation such as waterwheel, knowledge of double cropping, production of cash crops. The ancient civilizations of India were directly impacted by the strengthening and weakening of ISM, whereas for the later periods, civilizations were able to adapt to climate change. • Increased ISM precipitation during global warm periods mHCO, MWP, RWP, MCA and CWP. • Decreased ISM precipitation periods corresponded with Bond events (0–3). • Solar forcing and high latitude climate teleconnections shaped ISM variability. • Ancient Indian civilizations (IVC and Vedic) were impacted by ISM variations. [ABSTRACT FROM AUTHOR]