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The region around the coastal Chennai area, India, is drained by three major rivers that rise from the remnants of the Eastern Ghats and receive dominantly the northeast rains. These rivers meander short distances, deposit sediments into the Bay of Bengal and preserve signatures of past phases of sedimentation and incision. In this study, detailed mapping using satellite imageries and extensive field work, logging of the river cliff bank sections was supported by sediment texture and structure and optically stimulated luminescence (OSL) dates. The main objective of this study was to infer the major periods of aggradation and incision in coastal drainage basins receiving dominantly the northeast rains. Integration of all the earlier available dated alluvial sequences (14C ages) and the present study OSL dates reveal that a major period of sedimentation occurred during the early Holocene (9 to 8.3 ka), mid Holocene (7.6–5.5 ka) and late Holocene to recent (2.4 and 1.6 ka, 0.9–0.6 ka and around 0.2 ka) periods. The Koratallaiyar river has preserved older middle Holocene terraces. Younger ages of the south easterly and east flowing rivers such as the Palar and the Coovum signify that they have incised and eroded to the present riverbed levels by catastrophic floods during the late Holocene period. This has resulted in an imbalance between sediment supply and sediment transporting power thus laterally stacking sediments rather than vertically. [ABSTRACT FROM AUTHOR]

This study examines the catchment and source morphodynamics of the Palar River, Southern Peninsular India. Here, we applied a multidisciplinary approach (Remote sensing Techniques, Lineament Analysis, Geochemistry and Ground Penetration Radar) for a better understanding of its evolution during Holocene times. The lineaments present in the Palar River basin are showing dominantly NE-SW trend. There are five major faults identified in the Palar River basin. Fault F1 (strike slip fault) occurs in the upper part of the Palar River following the NE-SW trend. Other major faults F2 and F3 occurs in the middle reaches with a transition zone where frequent smaller magnitude earthquake occured and fault F4 traverses in parallel to the Cheyyar River. Fault F-5 nearer to the east coast indicates a passive tectonic activity regime. The after-effects of tectonic activity in the basin is further implicit from the GPR Profile. The sediments of active Palar River are dominantly litharenite, arkose, wacke; while, the paleochannels are shale in composition. Weathering proxies such as CIA, PIA, elemental ratios along with A–CN–K plot indicate a post-depositional intense weathering due to climatic variability for paleochannel sediments. Due to ongoing tectonic activity in the sources region along with subsequent aggradation and degradation in fluvial regimes, the sediments of active Palar River shows low to moderate weathering. Moreover, the geochemical data also reveals that the sediments from the Palar River and paleochannels are predominately from active continental and passive continental margins respectively. Moreover, the Major Oxide, Trace Elements and REE elements data indicate that Palar River sediments are from a felsic source while paleochannels are from mafic source. Hence, our study suggests that the catchment area of the Palar River has been shifted to the southward during the Holocene period due to tectonic uplift. Subsequently, the sediments of the paleochannels have undergone post-depositional weathering. Due to ongoing tectonic activity and intense precipitation in the region, enhances rapid erosion in the catchment area results in the deposition of the huge thickness of sediments from the middle to lower reaches of active Palar River. [ABSTRACT FROM AUTHOR]

Paleoclimate investigations and reconstruction using the lake sediment cores of Kashmir Valley have been rarely attempted. The basin is influenced by Indian Summer Monsoon, Westerlies and the local katabatic winds. In the present study, an 80 cm undisturbed sediment core was retrieved from the Manasbal Lake situated in North western Himalaya. Sediments were dated using 14C method, and the age-depth model indicated a depositional history extending from ∼3345 yrs BP to the present. Grain size, major and trace elements, TOC, OM contents C/N ratio and diatom assemblages were applied to reconstruct the paleoenvironmental changes around the area. The A-CN-K diagram displays that the weathering intensity of the Manasbal lake sediments are moderate to highly weathered and the sediments have been derived from nearby and mixed source origin. Several wet and cold phases were identified during ∼3300 yrs BP to ∼2500 yrs BP and ∼1800 yrs BP to ∼1300 yrs BP due to intense precipitation reflect high lake level. These wet phases are marked by higher sand and silt content, C/N ratio and high allochthonous input with less abundance of diatom species, clay, OM, TOC contents and high CIA values. Consequently, low lake level and dry and cold period from ∼3345 yrs BP to ∼3300 yrs BP and ∼2500 yrs BP to ∼1800 yrs BP is observed. These inferences are corroborated with the trace elemental ratios CIA and CWI data. Our data indicate that the Westerlies and localised katabtic winds rather than the Indian summer monsoons played a major role in controlling the past climate around the Manasbal lake, Kashmir Valley. [ABSTRACT FROM AUTHOR]

Geomorphic, tectonic and sedimentary investigations have been carried out to understand the landscape evolution of the Palar River basin, Southern Peninsular India. For this purpose, satellite data interpretations coupled with field investigations, fluvial architecture and optically stimulated luminescence (OSL) dating methods were adopted to infer climatic variations and neotectonic deformation that took place during the mid to late Holocene period. Several paleochannels have been identified in the Northern part of the present day Palar River. The distribution pattern of the Palar paleochannels and its present course indicate its migration towards the south, leaving behind the old Palar River streams as paleochannels. Significant changes in the morphological characteristics, channel width and river pattern in the successive paleochannels reveal evidences of channel movement by avulsion largely controlled by reactivation of pre-existing lineaments and intensified NE monsoon. Based on OSL ages, two major phases of migration have been identified that occurred between 4.83 ka to 1.88 ka. First phase occurred between 3.59 ka to 3.26 ka due to intensified monsoon accompanied with small scale neotectonic activity. The second phase took place between 2.42 ka to 1.88 ka which occurred probably due to the rapid upstream avulsion. This rapid avulsion is due to the close proximity of MPA and the reactivation of the pre-existing lineaments. Moreover, the present Palar River basin exhibits evidences of neotectonic activity such as soft sediment deformation structures, anomalous drainage deflections and reactivation of lineaments and faults further indicating that the Palar River is still draining a tectonically active region. Thus, neotctonics and fluctuations in the intensity of monsoon are largely responsible for sculpting the present landscape. [ABSTRACT FROM AUTHOR]

Point technologies form a key component of Middle Palaeolithic and Middle Stone Age industries across the Old World. However, only limited attention has been paid to the appearance of point technologies in the South Asian context. Two recent studies have indicated that the lack of Indian point technologies that are analogous to those known from the African Middle Stone Age and Arabian Middle Palaeolithic presents the basis to reject models for modern human dispersals into India associated with Middle Palaeolithic technologies. This study examines the role point technologies play in the Middle Palaeolithic record of the Thar Desert and situates them within the wider context of South Asia and adjacent regions to the west. A synthesis of existing evidence indicates that points form a key component of Middle Palaeolithic industries in the Thar Desert. New descriptions of Middle Palaeolithic artefacts from the Thar Desert highlight the repeated presence of debitage and façonnage approaches which suggest the use of specific reduction strategies in point production, rather than opportunistic or expedient methods. These results are placed in the wider context of the role points have played in Middle Palaeolithic reduction strategies within South Asia. Given the presence of point technologies in the Thar Desert that are comparable with contemporaneous technologies in North Africa and Arabia, we suggest that Middle Palaeolithic dispersal models cannot be rejected on the basis of their absence. [ABSTRACT FROM AUTHOR]

In the present study, a 60 cm sediment gravity core collected off the Cuddalore shore (11°42.419 N, 79°57.993 E) from a water depth of 150 m was radiocarbon dated and analysed for major elements (Si, Al, Na, K, Ca, Mg and P), trace elements (Fe, Cr, Mn, Co, Ni, Cu, Zn and Pb), calcium carbonate, and organic matter content to understand their behavior and probable sources and also to understand the monsoon variability. The sediment core has been radiocarbon dated from around 4100 to 3100 BP. High sand around 4000, 3700, 1500 BP with low CaCO 3 content suggests high sediment flux coupled with higher precipitation corresponding to increased erosion during these periods, and more fresh water runoff from rivers in the late Holocene, thus reflecting intensification of the SW and NE monsoon. The results of the major elemental analyses show the fine-grained, detrital nature of sediments with high values of Si and lower values of Al and Fe. The present study clearly demarcates that the distribution patterns of Cr, Cu, Pb and Zn that are controlled by the distribution of the fine grained fractions. The increased Mn content towards the lower end of the sediment core denotes the allogenic supply of Mn from oxic to-sub-oxic recycling within the sediment column in fine grain sediments. The mean CIA values (56.47) reflect immature, moderately weathered sediments that are mostly derived from sandstone and clay. [ABSTRACT FROM AUTHOR]

A sediment core retrieved from the Andamans Forearc Basin (AFB) near Landfall Island, North Andaman, provides a record of sediment provenance and climate change during the mid to late Holocene. Radiocarbon ages ranging from 6078 to 1658 indicate that the core represents the interval from 6500 BP to the present. Grain size variation indicates a cyclic variation of wetter and drier conditions corresponding to changes in intensity of the Indian Summer Monsoon (ISM), which was at greatest intensity near 6400, 5300 and 3300–3000 BP. Geochemical parameters including abundance of CaCO 3 , εNd and δ 18 O in Globigerinoides ruber are consistent with a long-term trend from cooler, wetter conditions to the warmer, drier conditions at present. Chemical weathering intensity, which lags behind climate changes on land, shows a pulse of highly weathered sediment deposited at about 4000 BP. During the short-duration pulses of intense monsoon activity, sandy sediment was supplied from the Andaman Islands. The Irrawaddy, Salween, and Sittang rivers of Myanmar are the secondary sediment sources for the study area. [ABSTRACT FROM AUTHOR]

Abstract: Pookode Lake, Kerala, South India, a fresh water lake situated at an altitude of ∼770 m.a.s.l., receives predominantly rains from the south-west monsoon. A sediment core 125 cm long was investigated for sediment texture, dating and geochemical composition. Radiocarbon dates obtained on the organic carbon rich sediments of the Pookode Lake range in age from the mid-Holocene to more recent (6240–565 14C BP; BC 4786 to AD 1434 cal.). Geochemical data of the sediment cores were corroborated with phytolith and pollen studies. Although phytoliths occur in the entire sediment core, pollen assemblages start occurring only since 1500 14C BP (∼AD 650 cal.). The sediments older than 1500 14C BP were not suitable for the preservation of the pollen assemblages. There is a major change in the lake hydrology, indicating lacustrine conditions subsequent to 1500 BP. Occurrence of diatoms in the upper sediment layers of the sediment core indicates shallowing of the lake. Both the Medieval Warm Period (MWP) and the Little Ice Age (LIA) are represented in the Pookode Lake sediment core. Sediment texture, chemical weathering intensity (CWI) values supported by phytolith and pollen assemblages, indicate that overall warm and dry conditions prevailed during 6200–420 14C BP (BC 4786–AD 1434 cal.) but this was interrupted by short, intense wet phases between ∼3900 and ∼1900 (∼BC 4000–∼AD 300 cal.), ∼1400–∼760 (∼AD 800–∼AD 1200 cal.), and ∼420–∼140 14C BP (∼AD 1570–∼ AD 1860 cal.). The wet events resulted from the strengthening of south-west monsoon (SWM) causing rising water levels and brief expansion of the Pookode Lake margin. [Copyright &y& Elsevier]

Abstract: The Thar Desert marks the transition from the Saharo-Arabian deserts to the Oriental biogeographical zone and is therefore an important location in understanding hominin occupation and dispersal during the Upper Pleistocene. Here, we report the discovery of stratified Middle Palaeolithic assemblages at Katoati in the north-eastern Thar Desert, dating to Marine Isotope Stages (MIS) 5 and the MIS 4–3 boundary, during periods of enhanced humidity. Hominins procured cobbles from gravels at the site as evidenced by early stages of stone tool reduction, with a component of more formalised point production. The MIS 5c assemblages at Katoati represent the earliest securely dated Middle Palaeolithic occupation of South Asia. Distinctive artefacts identified in both MIS 5 and MIS 4–3 boundary horizons match technological entities observed in Middle Palaeolithic assemblages in South Asia, Arabia and Middle Stone Age sites in the Sahara. The evidence from Katoati is consistent with arguments for the dispersal of Homo sapiens populations from Africa across southern Asia using Middle Palaeolithic technologies. [Copyright &y& Elsevier]

Abstract: There is no major chemical variation in the late Quaternary calcic nodules formed within vertisols in the foot-hill regions, and hardpan calcretes (greater than 200 ka) formed over the Precambrian substrate that occur as duricrust horizons in the plains around Coimbatore region, Tamil Nadu, India. The bulk chemistry of calcic nodules and the hardpan calcretes show very little variability in CaO, SiO2, Al2O3 and Fe2O3 content. The trend of trace metal content in calcic nodules and in the hardpan calcrete is Mn > Zn > Ni > Cr > Pb > Co > Cu and Zn > Mn > Ni > Co > Pb > Cu > Cr respectively. PAAS-normalised REE data of the calcretes (calcic nodules and the hardpan) demonstrate a positive Euanomaly. This could be attributed to feldspar, apatite mineral alteration and soil digenetic processes, differential weathering leaving behind plagioclase phenocrysts and apatite grains which are enriched in Eu. The stable isotope values of the calcic nodules do not exhibit a wide range (δ18O −3.39 to −5.84‰ and δ13C −3.01 to −6.64‰), compared to the hardpan calcretes (δ18O −2.91 to −12.98‰) and δ13C (−0.05 to −7.4‰). The palaeoenvironment during the formation of the calcretes nodules was dominated by the C4 plants with sparse vegetation cover and that the parent material/bedrock supported a thin veneer of soil column with sparse vegetation cover as present day. Calcic nodule accumulations in the soils has resulted from differential weathering and chemical histories within the soil profiles while the hardpan calcretes formed by complex pedogenic and chemical – groundwater processes in arid – semi-arid conditions over along geological period. During the late MIS3 to the LGM period the south west monsoon was weak with mean annual rainfall (MAR) between 300 and 500 mm/yr, the sea level was low and the rainfall at the time of carbonate formation would have remained damp enough to allow silicate weathering of the soil sediments. [Copyright &y& Elsevier]

The present study was carried out to determine the characteristics, distribution, and abundance of plastic debris in 25 sediment samples collected from the Poompuhar beach, southeast coast of India. The result reveals that the mean plastic debris abundance was 42 ± 27 particles/m2 dry weight (dw) (1 SD, n = 25) with higher concentrations in the river mouth. The dominant shapes in the study area were fragment (70.7%), followed by fiber (20.7%), and pellet-shaped (8.6%). The dominant colors of the plastic debris were: white-colored (47%) followed by blue (28%) and green (14%). The study further reveals that the dominant polymer type was polyethylene (PE, 63.4%), followed by nylon (PA, 16.9), polyvinyl chloride (PVC, 15.5%), polypropylene (PP, 3.1%), and polystyrene (PS, 1.1%). In the study area, the main source of plastic debris was from land-based fishing and tourism activities, and rainwater runoff from the Cauvery River. [Display omitted] • Plastic pollution was addressed along Poompuhar Beach, south east coast of India. • Dominant plastic shape was fragment (70.7%) > fiber (20.7%) > pellet (8.6%). • Plastic debris sources mainly from the terrestrial and marine sources. • Polyethylene (PE, 63.4%) was the dominant polymer in the study area. • Dominant plastics size was meso (68.1%), and micro (25.2%). [ABSTRACT FROM AUTHOR]

Abstract: Understanding the development of calcic and petrocalcic horizons is important for palaeoclimate reconstruction. The micromorphology and geochemistry of Quaternary calcic and petrocalcic horizons formed in the area around Coimbatore, Tamil Nadu are discussed. The calcic horizons represent the Bk horizons that occur as thick complex profiles (∼300cm thick) in the foothill regions while the laminar petrocalcic horizons representing the K horizon (80–100cm thick) formed on hard rock in the topographic low-lying area. Calcic horizons are represented by powdery, nodular calcrete nodules and root casts with 95.2–64.5% of CaCO3. Laminar petrocalcic horizons are compact with well rounded coalesced nodules and contain 56–64% CaCO3. Micromorphological study of the calcic horizons show the occurrence of alveolar septal structures, calcified filaments, coated grains, spherulites, calcified root cells and calcispheres that indicate biogenic origins, mainly induced by plant root related microbial activity. The calcic nodules within the calcic horizons consist of quartz sand grains cemented by finely crystalline, grain-coating, often glaebular and pore-filling micrite. This development has taken place in phases of soil formation, erosion and reworking. The inter-relationships between these processes have caused variations in the phases of accretion of soil profiles developed in the foothill region. Microfabrics of laminar petrocalcic horizons with detritus hosts show replacement, corrosion, displacement and shrinkage indicating that the laminar petrocalcic horizon formed under relatively semi arid conditions. These characteristics indicate that the laminar petrocalcic horizons formed in a moderately near-surface environment with relatively high rates of evaporation and ground water action and are polygenetic in origin. [Copyright &y& Elsevier]

Abstract: Pedogenic carbonates in a 19m-thick dune section (16R) at Didwana, and several shorter profiles from the eastern margin of the Thar Desert, Rajasthan, were studied for their stable isotope composition. Carbon isotope results show the C4 biomass (grasses?) has dominated local vegetation for most of the 250,000years represented by the 16R section. Our results display a decrease in δ 18O and δ 13C values during the last interglacial and early glacial periods. The higher δ 13C values in our dune records correlate to episodes in the strong upwelling and decreased sedimentation rates in Indian Ocean cores, probably the result of a strong Asian Monsoon. The high δ 13C values may, therefore, denote the expansion of C4 vegetation in response to warm, wetter monsoon circulation. Conversely, low δ 18O and δ 13C values mark the expansion of C3 vegetation, probably caused by enhanced winter rains and lower temperatures. [Copyright &y& Elsevier]

Calcretes formed over bedrock such as Precambrian hornblende-chlorite schist, rhyolite and carbonaceous phyllites in Western Rajasthan, India, were studied for their mineralogical composition and geochemistry. They form a distinct element of the Quaternary landscape of Western Rajasthan, India. The study area is located within the Nagaur–Churu–Jaipur tract of Western Rajasthan. The purpose of this study was to determine the processes governing the development of hardpan calcretes, and to evaluate the local and regional controls on their formation.Micromorphology included pedogenetic and groundwater features within the hardpan calcretes. Thickening of calcite laminae downward and tapering at the sideward edges around the unweathered minerals of quartz and feldspars indicated cumulative and compound pedogenesis, which probably occurred locally, and downward movement of carbonate solution and pore water. Carbonate solutions were probably derived from the upper horizons or surfaces bringing about the process of dissolution and recementation of individual laminae. Occurrence of fibrous palygorskite as coatings around the detrital grains and siderite (oolitic and pisolitic in shape) points to a subalkaline–subacidic process of pedogenesis in a semi-arid to arid climate. Stable δ13C and δ18O isotope data of the hardpan calcrete laminae vary between 0.3‰ to 1.5‰ and −5.9‰ and −1.5‰, respectively indicating their formation at or near surface (capillary fringe), probably supporting a thin column of soil. The source of most of the calcite is groundwater; however, calcite nodule formation was largely dependent on pedogenic processes associated with evaporation, evapotranspiration and /or microenvironmental changes in pH and CO2 partial pressure. Dust is also a major source for carbonate precipitation. Although it is commonly assumed that the powdery calcretes are younger in age compared to the more complex forms, the occurrence of Middle Palaeolithic tools below the hardpan calcrete at Roopangarh and Dayalpura, and above the hardpan calcretes at Mitri, Genana and Rol, indicates that the morphology of calcretes is not a reliable indicator of age. [Copyright &y& Elsevier]

The Thar Desert, located in western South Asia, marks a major global biogeographic boundary and a major adaptive threshold for the eastward expansions of modern humans from Africa across Asia. Examining the framework of palaeoenvironmental change in this region, both in terms of the regional manifestation of global climate change and the physical geography of the landscape, is therefore important to understand how modern humans first engaged with this significant shift in ecology. Here, we present evidence for the oldest chronometrically dated evidence for fluvial activity within this region, located at the Nal Quarry site in the central Thar Desert. We use luminescence dating of alluvial facies to demonstrate phases of fluvial activity at the site at ∼172–174, 140–150, 79–95 and 26 thousand years ago. This result substantially extends existing evidence for fluvial activity within the Thar Desert, as well as overlapping with evidence from the southern and eastern Thar desert indicating increased fluvial activity during the Last Interglacial (Marine Isotope Stage 5), whereas the cessation of fluvial deposition at Nal Quarry is contemporaneous with the onset of activity within the Ghaggar-Hakkra channel in the northern and western Thar Desert. Critically, the phases of fluvial activity identified at Nal overlaps with substantial behavioural change across South Asia, as well as the wider expansion of modern humans across the continent. This research illuminates a dynamic fluvial landscape that existed in the late Middle Pleistocene and early Late Pleistocene at a key threshold for modern human dispersals. • We identify the deep Quaternary fluvial deposits in the central Thar Desert. • OSL dating constrains major episodes of fluvial activity to MIS 6 and 5. • Fluvial activity at Nal predates other fluvial deposits across the Thar Desert. • First ground truthing and dating of results of remote sensing studies. • Results highlight fluvial dynamism across Thar Desert at key threshold for human dispersal. [ABSTRACT FROM AUTHOR]

The Indian Peninsula is generally considered as a tectonically stable region, where ancient rocks, rivers and land surfaces predominate. In some parts of this ancient landscape, however, the role of tectonic landsculpting is strongly indicated by the presence of youthful topography and historical seismic activity. The present study is primarily focused on the middle domain of the Kaveri River, which displays such youthful features. The tectonic controls on this cratonic river were evaluated on the basis of the investigations of the longitudinal profiles, morphotectonic indices of active tectonics, and fluvial records. The presence of steep channel gradients, prominent knickpoints, hanging valleys, narrow bedrock gorges, and channel-in-channel morphology imply rapid erosion rates in the middle domain of the basin in response to active deformation, particularly in the reach defined by two major active faults — the Kollegal–Sivasamudram Fault and the Mekedatu Fault. Further, considering the remarkably low modern and long-term denudation rates and OSL ages of the alluvial deposits (30–40 ka), the tectonically-driven rejuvenation does not appear to be geologically recent as postulated by earlier workers. [ABSTRACT FROM AUTHOR]

The Indian subcontinent contains a number of volcanic ash deposits representing the Youngest Toba Tuff (YTT) volcanic eruption of 75,000 years ago, though relatively few localities have been reported in detail. Here, we identify tephra deposits in the Sagileru Valley, south India, in association with Palaeolithic industries. The glass shard and biotite composition of the Sagileru tephra matches that of the YTT from other terrestrial sites in India and from the Toba caldera, and are distinct from earlier large eruptions from Toba. Moreover, our survey identified rare associations between lithic artefacts and YTT deposits, making the Sagileru Valley one of the few globally identified locations with both ash and archaeology. The identification of ash deposits and stone tool assemblages in the Sagileru Valley provides another source of information for understanding Late Pleistocene climate change, depositional environments and hominin occupations of South Asia. [ABSTRACT FROM AUTHOR]

North Africa is a key region hosting ca. 230 million people that are dependent on climate to maintain their subsistence through agriculture. Because of the current global changes, understanding the mechanisms behind the climate variations that occurred in this region is extremely important. To contribute to a more accurate modelling projection, we reconstructed the paleoclimatic and paleoenvironmental variations from the Meghalayan (∼1,500 ka) to recent using palynological and geochemical data from a sediment core from El-Beida Lake (Wadi El-Natrun area, north Western Desert of Egypt). North Africa underwent significant shifts in climatic conditions forced by different drivers since the Roman Warm Period (RWP) until recent. Our sediment core record indicates that this region experienced a persistent dry and warm climate during the RWP until the first half of the Medieval Climate Anomaly (MCA). The positive North Atlantic Oscillation was the main driver for controlling the precipitation pattern and pushing the precipitation towards central and north Europe and favoring the dry climate in North Africa during the RWP. The dry and slightly cold conditions in the study area during the Dark Age Cold Period (DACP) can be ascribed to the coupling between the more southward position of the Azores Front and the weak Atlantic Meridional Overturning Circulation. Northern Africa showed variable climatic conditions during the Medieval Climate Anomaly (MCA) due to the complicated thermohaline circulation of the Mediterranean Sea. During this time, the Eastern Mediterranean experienced a cold or partially cold MCA that may be extended to the present study area. An abrupt change to humid and cold climatic conditions occurred in northern Africa during the Little Ice Age (LIA) due to large-scale processes like the ENSO and NAO. The SST warming of the North Tropical Atlantic (NTA), significantly influenced by ENSO, causes the position of the Atlantic ITCZ to be shifted northward affecting precipitation in Africa. • Palynological and geochemical proxies reveal the Holocene paleoclimate variabilities in North Africa. • North Africa experienced a dry and warm climate during the Roman Warm Period (RWP). • Dry and slightly cold conditions prevailed during the Dark Ages Cold Period (DACP). • During the Medieval Climate Anomaly (MCA), North Africa showed dry and cold climatic variables. • Abrupt change to humid and cold climatic conditions occurred in northern Africa during the Little Ice Age (LIA). [ABSTRACT FROM AUTHOR]

[Display omitted] • Wular Lake levels, redox conditions, and organic matter supply significantly altered over the last ∼4.2 kyr BP. • Hydroclimate varied from early wetter to relatively drier conditions and severe drought before the wet Little Ice Age. • Latitudinal migration of inter-tropical convergence zone drove seasonal precipitation turnover in Kashmir Valley. • A spatially coherent hydroclimate is found in the Northwest Himalaya during the late Holocene. This study focuses on the immensely debated pre-instrumental centennial–millennial scaled forcing of the late Holocene hydroclimate variability in the Northwest Himalaya (NWH). The Wular Lake is ideally situated close to the modern intertropical convergence zone (ITCZ) in the NWH and fed by the Jhelum River draining the vast Kashmir Valley, which receives seasonal precipitations from the Indian Summer Monsoon (ISM) and Western Disturbances (WD). In this study, size segregated lithic fractions (sand, silt, and clay) and elemental concentrations (TOC, TN, Ba, Al, Mn, and Fe) have been measured in the 14C-AMS dated NWC sediment core collected from this lake. The continuous NWC sedimentary records reveal temporal environmental changes (water level, organic detritus supply, and redox conditions) in this open mega-lake system suggesting prevailed hydroclimate variations in the valley during the late Holocene. The captured hydroclimate variations are a wetter phase (∼4.2–3.4 cal kyr BP) followed by relatively drier conditions and extreme drought before the wet Little Ice Age (LIA). The plausible forcing seems to be the latitudinal ITCZ migration regulated seasonal precipitations from the tropical/subtropical moisture sources. The ISM to WD moisture turnover dominated winter over summer precipitations in the valley during the former warm and wet phase but unequivocally reflected during the cold and wet LIA. Additional hydroclimate control comes from permafrost ice melting episodes of a few centuries duration during high solar activity events (sunspot number ≥50). A comparison with the regional studies further indicates that NWC records capture hydroclimate signatures widespread in the NWH. [ABSTRACT FROM AUTHOR]