The National Centre for Polar and Ocean Research, (NCPOR) formerly known as the National Centre for Antarctic and Ocean Research (NCAOR) is an Indian research and development institution, situated in Vasco da Gama, Goa. It is an autonomous Institution of the Department of Ocean Development (DOD), Ministry of Earth Sciences, Government of India which is responsible for administering the Indian Antarctic Programme and maintains the Indian government's Antarctic research stations, Bharati and Maitri. NCPOR was established on 25 May 1998, with Dr. Prem Chand Pandey as its founding director. NCPOR is known for its participation in global experiments, hosting of international conferences and in the leadership of international committees concerned with Antarctic science. At present, NCPOR is an agency working under the Ministry of Earth Sciences, Government of India since 2006, by the notification of the President of India. NCPOR complex is a home to a special low-temperature laboratory and is setting up a National Antarctic Data Centre and a Polar Museum. The NCPOR operates in different fields or tasks: storing ice core samples, from Antarctica and the Himalayas. operating the Himadri and IndARC Arctic research stations in Svalbard, Norway. managing the oceanic research vessel ORV Sagar Kanya, the flagship of India's fleet of oceanographic study vessels. This ship has contributed significantly to India's study of the Arabian Sea, the Bay of Bengal, and the Indian Ocean. it supported the KBCAOS, University of Allahabad from initial stage of establishment up to the final stage of the center as full-fledged faculty centre, in form of a project as per collaborative work with the University.This centre was previously referred to as the Antarctic Study Centre. It came into existence with joining of Dr. P. C. Pandey as the director on 12 May 1997.
Seismic activity can impact different layers of the Earth’s atmosphere; however, our understanding of lithosphere-atmosphere-ionosphere coupling mechanism still remains limited and is challenging. Previous studies predominantly feature seismo-ionospheric changes associated with large earthquakes/tsunamis. Seismic-induced changes in the Mesosphere-Lower Thermosphere (MLT) region have not been properly addressed and are limited to a few reports. We present, here, rare observations of anomalies in the temperature and airglow of the MLT region using Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on board Thermosphere Ionosphere Mesosphere Energetics Dynamics (TIMED) spacecraft measurements for 2025 Mw 8.8 Kamchatka Peninsula Earthquake. Beginning with the Mainshock at 23:24:52 UT on 29 July 2025, over a hundred aftershocks (with a majority exceeding intensity-scale of Mw 5.0) occurred near Petropavlovsk-Kamchatsky and Severo-Kuril’sk in Russia and activity continued beyond 31 July. We found an increase in temperature in the 73–83 km range on 30 July. However, the temperature decreased in the 87–97 km range on 30 and 31 July. Further, we noted a minor increase and distinct decrease in the volume emission rate of OH airglow on 30 July over the height range of 76–82 km and 83–90 km, respectively. Comparatively, significant decrease in OH airglow was seen on 31 July in the 81–96 km height range. Unusual gravity wave (GW) activity was, also, noted with predominant presence of waves with vertical wavelength of 18 km. Similar anomalous temperature enhancement and pronounced decrease in OH airglow was seen during the 2011 Mw 9.1 Tohoku-Oki earthquake as well.
The Indian Monsoon System, an integral part of the Asian Monsoon, is intricately linked to the global climate system through solar forcing, abrupt warming or cold events in the Northern Hemisphere, and deep ocean circulation. This study reconstructs the sedimentation history and its linkages to monsoon seasonality and intermediate-to-deep ocean circulation over the last 50 ka using well-dated sediment core SK-257/02 from the southeastern Arabian Sea (SEAS). Environmental magnetic parameters (concentration, mineralogy, and grain size) combined with the end-member analysis reveal three dominant sedimentary components. The fine-grained fluvial suspension-driven fraction (EM1- mean size 3.46 mu m) reflects intensified Indian Summer Monsoon (ISM) precipitation during the interglacial periods (MIS 3 and 1) and warmer phases of Dansgaard-Oeschger (D-O) cycles, associated with precession-driven changes in solar insolation. In contrast, the Northeast Monsoon (NEM) wind-driven aeolian silt fraction (EM2, mean size 5.59 mu m) dominates during glacial stages (especially the last glacial maximum; LGM) and Heinrich events (HS). The co-occurrence and compensatory depositional behavior of EM1 and EM2 demonstrate the seasonal occurrence of the South West Monsoon (SWM) and NEM during the glacial-interglacial cycle. The fractional abundance of the coarsest fraction (EM3, mean size 15.92 mu m) shows coherence with enhanced southern component waters (SCW)- Antarctic Bottom Water: AABW and/or Pacific Deep Water: PDW), admixed intermediate-to-deep circulation across the Arabian Sea, Equatorial Indian Ocean, and the Bay of Bengal, particularly during glacials and stadials. This signifies that the resuspension of fine-tomedium silt-sized sediment is associated with stronger circulation at intermediate water depths, temporally synchronizing with colder Antarctic and Southern Ocean episodes, promoting the advent of more SCW admixed Circumpolar Deep Water (CDW) into the Northern Indian Ocean. This suggests a teleconnection with the SEAS through altered intermediate and deep-water circulation, linked to the deep-water mass structure and global overturning circulation changes in the glacial deep ocean.
The Arabian Sea sediments have the records of significant temporal and spatial variations in response to the neotectonic changes, paleoclimatic and paleo-sea level fluctuations particularly from the Quaternary period. In this study area, environmental mineral magnetic parameters, diffuse reflectance spectroscopy (DRS), XRF (Fe/K, Ti/Al and Ca %) have been studied in an AMS radiocarbon dated core- SK240/473 from the coast off Saurashtra, south-western part of Gujarat State, north-western continental margin of India, to unravel paleoclimatic and paleoceanographic sedimentation and sea level changes over the past 15 ka BP. Currently, the rainfall of this region mainly occurs during the summer monsoon season. Based on results of multi-proxies measured in this core indicate that three major changes in the climate: phase- I before the Holocene thermal maximum (HTM), phaseII during the HTM, and phase- III after the HTM. The phase-I is mainly characterized by abundance of hematite over goethite with high carbonate content, but lower in total organic carbon (TOC) and chemical weathering index (CWI) suggesting arid climate of oxidizing environment of sediment deposition during the rapid sea level rise from 14.5 ka BP to 12.0 ka BP with a standstill sea level from 12 ka BP - 10 ka BP. In contrast, the phase-II marked by a transition from arid to humid condition of sediment deposition characterized by higher CWI, abundant TOC and goethite, but lower in hematite and carbonate concentrations reflecting humid climate of reducing environment of sediment deposition during the Holocene thermal maximum (HTM) from 10.00 ka BP to 5.50 ka BP. Interpretations made here are generally in good agreement with the deglacial to Holocene Sea level fluctuations curve proposed for the west coast of India. In Phase III, the chi lf, chi fd, and Chemical Index of Alteration (CIA) data from sediments deposited after the HTM largely suggest deposition in a humid environment, occasionally interrupted by arid episodes in the study region's hinterland. Such arid events linked to paleo-El Nino episodes recorded in the tropical eastern Pacific Ocean. This interpretation is further supported by the reason explained to the current rainfall variability in the hinterland of the study area. Overall, the data of the core studied reveal significant environmental, sea-level and monsoonal changes in the NE Arabian Sea since the deglacial period. The goethite/hematite (G/H) ratio, chi lf and chi fd profiles which is an indicator of humidity/aridity and coastal upwelling are different from the sea-level curve, suggesting that formers are better indicator of monsoon intensity that often regulated by the ENSO.
Abstract Understanding the coastal zone of the Antarctic Ice Sheet (AIS), where it interacts with the Southern Ocean and warmer air masses, is crucial for predicting Antarctica's influence on the global climate and sea level. This region has multiple tipping mechanisms that could trigger large, rapid, and potentially irreversible changes in the AIS, the Southern Ocean and their global connections in the coming centuries. The AIS remains the largest source of uncertainty in future sea‐level projections. Bed topography beneath the ice shelves and the coastal ice sheet is not yet well documented, and is a major source of this uncertainty. This review assesses current knowledge of the coastal zone and highlights methods to investigate it, including aerogeophysical surveys, ground‐ and ship‐based measurements, satellite observations, and computer modeling. An ensemble analysis of published bed topography data sets identifies significant data gaps and their regional distribution, framed in the context of current ice‐sheet behavior and potential instability. We propose scientific priorities and guidelines for future aerogeophysical surveys, advocating for a comprehensive, coordinated international effort to build a next‐generation data set of Antarctic bed properties. Such an initiative would significantly advance understanding of the role of coastal processes in ice‐sheet dynamics, reducing uncertainties in sea‐level rise projections and improving predictions of future ocean and climate changes.
The present study reports a geochemical evaluation of Permian aged Raniganj, Barren Measure and Barakar shales from R1 and R4 boreholes from the NE part of the Raniganj sub-basin. We have investigated organic matter characteristics, stable isotopic composition, hydrocarbon potential and kerogen kinetics to decipher shale gas potential as well as artificial hydrocarbon generation prospect. The shales contain high total organic carbon (TOC) content similar to 2.5-26.5 wt%, mainly Type III kerogen with minor Type II/III kerogen. The provenance of organic matters has been determined using delta C-13(org) and delta N-15(bulk) composition and Total Nitrogen content to be predominantly terrestrial deposited primarily in an oxic to suboxic environment. Kinetic parameters for kerogen degradation reactions namely, activation energies (Ea) distribution, frequency factors are in the range of typical Type III kerogen. A narrow range of peak Ea distribution indicates relative homogeneity of organic matter which is also evident from FTIR spectra showing relative abundance of aromatic compounds. Maceral assemblage reveals substantial presence of Type I/Type II liptinite macerals namely, alginite, sporinite, cutinite along with Type III vitrinite macerals which likely elevated the kerogen type and hydrogen index (HI), and resulted in a narrow Ea distribution. The kerogen transformation ratio and the hydrocarbon generation rate indicate considerably earlier onset of kerogen transformation and quicker completion of hydrocarbon generation for R4 shales suggesting better potential for R4 shales relative to R1 shales. Furthermore, Rock-Eval parameters S2, TOC, Hydrogen Index, T-max summarise that the shales derived predominantly from terrestrial sources contain mainly Type III with some mixed Type II-III kerogen with potential for wet/dry gas generation. In the absence of any post-depositional igneous activity in the NE part of the Raniganj sub-basin, the shales are in an early matured state unlike shales from the NW part.
