Indian monsoon

Although most data suggest that the India–Eurasia continental collision began approx 45–55 Myr ago, the architecture of the Himalayan–Tibetan orogen is dominated by deformational structures developed in the Neogene period (< 23 Myr ago). The stratigraphic record and thermochronometric data indicate that erosion of the Himalaya intensified as this constructional phase began and reached a peak around 15 Myr ago. It remained high until approx 10.5 Myr ago and subsequently slowed gradually to approx 3.5 Myr ago, but then ...

The Atlas of Maritime Silk Road Buddhism by Prof Lewis Lancaster contains a series of lectures he presented at the Department of Religious Studies for the University of the West in California.  These lectures give a description of the search for models that can deal with the study of how Buddhism spread from the Ganges Basin and established itself throughout the Southeast area of Eurasia.  In addition to the lectures, there are many images in the volume from the large museum exhibits that opened at the City University of Hong Kong and the Buddha Museum at Fo Guang Shan in Taiwan.  As part of the data collecting process, Prof Sarah Kenderdine from Lausanne, Switzerland secured a grant from the Australian Research Council to take 3-D and surround images from Buddhist sites tied to the maritime route from India to East Asia. More than three months of filming with camera crews in India, Myanmar, Thailand, Sri Lanka, Indonesia, Cambodia, and China resulting in a major collection of high density photographs, videos, and sound recordings.  These images were taken by Prof Jeffrey Shaw of Hong Kong and installed as museum exhibitions using 3-D and Virtual Reality that allow visitors to experience the art, architecture, and cultural features on the journey from the shores of India to China. This volume has now been produced by the Institute for the Study of Humanistic Buddhism at Fo Guang Shan to accompany the museum exhibits providing a description of the data used in filming and the research that helped create the story that is told about Maritime Buddhism.





















The Atlas of Maritime Silk Road Buddhism by Prof Lewis Lancaster contains a series of lectures he presented at the Department of Religious Studies for the University of the West in California.  These lectures give a description of the search for models that can deal with the study of how Buddhism spread from the Ganges Basin and established itself throughout the Southeast area of Eurasia.  In addition to the lectures, there are many images in the volume from the large museum exhibits that opened at the City University of Hong Kong and the Buddha Museum at Fo Guang Shan in Taiwan.  As part of the data collecting process, Prof Sarah Kenderdine from Lausanne, Switzerland secured a grant from the Australian Research Council to take 3-D and surround images from Buddhist sites tied to the maritime route from India to East Asia. More than three months of filming with camera crews in India, Myanmar, Thailand, Sri Lanka, Indonesia, Cambodia, and China resulting in a major collection of high density photographs, videos, and sound recordings.  These images were taken by Prof Jeffrey Shaw of Hong Kong and installed as museum exhibitions using 3-D and Virtual Reality that allow visitors to experience the art, architecture, and cultural features on the journey from the shores of India to China. This volume has now been produced by the Institute for the Study of Humanistic Buddhism at Fo Guang Shan to accompany the museum exhibits providing a description of the data used in filming and the research that helped create the story that is told about Maritime Buddhism.














The Atlas of Maritime Silk Road Buddhism by Prof Lewis Lancaster contains a series of lectures he presented at the Department of Religious Studies for the University of the West in California.  These lectures give a description of the search for models that can deal with the study of how Buddhism spread from the Ganges Basin and established itself throughout the Southeast area of Eurasia.  In addition to the lectures, there are many images in the volume from the large museum exhibits that opened at the City University of Hong Kong and the Buddha Museum at Fo Guang Shan in Taiwan.  As part of the data collecting process, Prof Sarah Kenderdine from Lausanne, Switzerland secured a grant from the Australian Research Council to take 3-D and surround images from Buddhist sites tied to the maritime route from India to East Asia. More than three months of filming with camera crews in India, Myanmar, Thailand, Sri Lanka, Indonesia, Cambodia, and China resulting in a major collection of high density photographs, videos, and sound recordings.  These images were taken by Prof Jeffrey Shaw of Hong Kong and installed as museum exhibitions using 3-D and Virtual Reality that allow visitors to experience the art, architecture, and cultural features on the journey from the shores of India to China. This volume has now been produced by the Institute for the Study of Humanistic Buddhism at Fo Guang Shan to accompany the museum exhibits providing a description of the data used in filming and the research that helped create the story that is told about Maritime Buddhism.

Was near coastal/marine, equatorial influence prevalent in North Indiasubcontinent 18.2 million years ago?
Ritesh Arya
168 Arath Bazaar, Kasauli, Himachal Pradesh
email: aryadrillers@gmail.com
Probably yes and this is what reinterpretation of the fossils and sedimentological data found from Kasauli Formation (dated to be Lower Miocene) and its equivalent in the Himalayas indicate. The sites from where fossils have been collected for the present study lie in Kasauli,Dharamsala, Udhampur, Jammu, Kalakot, Kargil, Alchi., Stok , Kangri range and Nyoma inthe northwestern Indian Himalayas. All these localities marked on the map and show an interesting structural pattern revealing a lot about the history of their genesis in geological time. Interestingly on ground all the fossil plant assemblage localities show great similarity in lithologies, fossils and type of preservations with each other. The most important being the taphonomic relationship between the fossil wood and the sandstone facies, which is quiet homogenous with other homotaxial localities or basins described above and show unmatched similarity in the environments of the deposition specially in the basins of Kasauli-Dagsahi, Dharamsala, Murree and Indus in Ladakh. Interesting observations made in the papers published earlier were reinterpreted based on the recent observations and fossil findings made by the author from differentlocalities along the Indus River in the high altitude, cold temperate climatic conditions of Ladakh, which indicate warmer and more humid climatic conditions at the time of deposition. Preliminary studies show that there was close similarity of the fossils of Garcinia, Gluta, Syzygium, Clinogene, Combretum and palms reported from Kasauli Formation with the extant taxa from coastal regions of Indo-Malayan including Borneo and Sumatra which indicate well hot humid equatorial climatic conditions of deposition withmajor representation of evergreen elements typical of near equatorial conditions and near shore coastal marine influence on otherwise terrestrial environment prevailed during thosetimes. Fossils of mega plants all along the Indo Malayan Indonesian islands establish land connections for their migration during those times. This fact on environmental regime (nearcoastal / marine transgression) at the time of deposition is further supported in Chitarwata Formation, west central Pakistan; Ladakh, North India Jammu, North India Dharamsala, Northwestern India; Kasauli, Northwest India Darjeeling,West Bengal, North Eastern Indiaand Bhutan. Based on the fossil findings of Mitrgyana from the Kasauli sediments elevation was also found to be less then 1300m in contrast to the present height of about 2000meters.This really meant that the Himalayas attained sufficient height to block the rain laden winds and thus the concept of monsoons was born. Presence of diverse assemblage of fossil flowers shows that seasonal changes had initiated during those times. It is very well documented fact that Subathu Formation enjoyed equatorial position during Lower Eocene times. From the above findings it can be interpreted that Kasauli Formation and its equivalent also enjoyed near coastal equatorial to subequatorial climatic conditions and latitudes may be around 5-10degrees north of equator at the time of deposition in contrast to 32 degrees. This implies that the major tectonic forces which were to give rise to the future Himalayas were not very active during those times . Northward dragging of the uplifted ztethyan basin (during Dagshai times) along with the Indian sub continent took place much later then 18.2 million years ago.

Stratigraphic exposures, fluvial archives and borehole data have been allowed to reconstruct the alluvial history of Late Pleistocene to Late Holocene and climate changes in the monsoonal wet – dry region of lower Damodar Basin (West Bengal, India). The facies architectures and climate proxies suggest that five to six climate changes occurred in between ~ 14 ka and 6 ka. Supporting evidence from the floodplain of Damodar River demonstrates that the successive phases of aggradation and incision were linked to the south-west monsoonal variability of Late Quaternary period. The onset of semi-arid climate was associated with caliches, pond and backswamp deposits of wanning low energy floods. The relatively warm-humid climate was associated with sandy bedforms, valley fills, slack water deposits and ferruginous nodules. This paper presents a synthesis of the available palaeoclimatic records from the lower Ganga Basin and the rivers of western and central India for the palaeoenvironmental significance of Late Quaternary deposits and discusses the influence of palaeoclimatic controls on the fluvial architectures and archives that developed below the floodplain of Damodar River. We have taken some representative studies from the region to reveal the spatial variability in fluvial successions in response to climate changes during this period.

Sedimentary archives in the Himalayan foreland basin and Indus submarine fan provide the most detailed records of how changing monsoon strength may have affected erosion and the development of tectonic structures in the western Himalaya during the Neogene. Muscovite Ar-Ar ages show that fast exhumation of the Greater Himalaya was earlier in the west (20–35 Ma) than in the central Himalaya (10–25 Ma), probably driven by progressive lithospheric slab tearing that caused both rock uplift and an intensified summer monsoon to start earlier in the western Himalaya. Rates of exhumation reduced after ~ 17 Ma as uplift also slowed, apparently unrelated to climate change. However, further reduction at 6–8 Ma coincided with a time of weakening summer rains, as shown by carbon isotope data from the foreland and hematite-goethite records from ODP Site 730 on the Oman margin. Coming at a time of stronger winds, this drying was linked to global climatic cooling. Weakening of Late Miocene monsoon rains coincided with a southward migration of the ITCZ and faster erosion of the Lesser rather than Greater Himalaya. Unroofing of the Inner Lesser Himalaya, starting after 9 Ma, followed as a consequence of duplex formation enabled by focused erosion, although widespread exposure of that range was delayed until after 6 Ma. Inner Lesser Himalayan exposure, combined with unroofing of the Nanga Parbat Massif, caused a decrease in average ε Nd values of Indus River sediment after 5 Ma, rather than large-scale drainage capture.

Three pairs of small, fourth-to sixth-order catchments (approximately 5-80 km 2), draining the margin of the Darjeeling Himalayas into the piedmont, were selected for a comparison of the land-use impact on the morphology and sedimentology of their stream channels. Each pair experienced similar annual rainfall and comprised similar metamorphic bedrock, steep topography, and brown soils; the members of each pair contrast with respect to their land-use structure as they comprise large forest cover (forest > 90%) and a significant contribution of agricultural land with tea plantations (forest < 63%), respectively. A set of rainfall, cross-sectional, and sediment data were collected for the characterization of the stream channels. The obtained results revealed that, under extreme rainfall and high denudation rates as well as frequent flash floods, the geomorphic response to land-use changes involving agricultural expansion at the expense of forest cover was less pronounced in the mountain channels than in the piedmont. Significant differences between the studied pairs of mountain streams draining forested and agricultural catchments were observed only at bankfull width and baseflow depth in fourth-order streams and baseflow depth in fifth-order streams. Local environmental factors such as bedrock channel boundaries, steep topography, high material supply to river networks, and selective sediment mobilization during extreme rainfall and floods override the effects of land use and exert dominant control over stream channels in mountain catchments. However, the effects of agricultural activity in mountains are propagated downstream. In the agricultural catchment in the piedmont, a local rapid decrease in river slope and an increase in water infiltration into alluvia facilitates the deposition of eroded material. In addition, the stream in the agricultural catchment exhibited a rise in the riverbed with the expansion of a braided channel over a dozen kilometers below the Himalayan front in the piedmont, while the streams in the forested catchment revealed a distinct tendency towards incision. The present-day channel morphologies and sediment patterns observed in forested catchments are most likely similar to those that existed in the studied rivers prior to the development of tea plantations and settlements in the mid-19th century.

അറബികളുടെ കടൽസഞ്ചാരവും വ്യാപാരവും ഇന്ത്യൻ മഹാസമുദ്രതീരത്തെ ജനസമൂഹങ്ങളുമായുള്ള ബന്ധങ്ങളും ആഴത്തിൽ പരിശോധിക്കുകയാണ് പുസ്തകം. വ്യാപാരബന്ധങ്ങളിലൂടെയും സൂഫികളിലൂടെയും സാധ്യമായ ഇസ്ലാമിക വ്യാപനത്തിന്റെ അടരുകളെ ഈ പുസ്തകം പരിചയപ്പെടുത്തുന്നു. ആധുനികലോകത്ത് ഏറെ ചർച്ചചെയ്യപ്പെട്ട ഈ ഗ്രന്ഥം, നിരവധി അവാർഡുകൾക്ക് അർഹമായിട്ടുണ്ട്.

Recent studies using coupled atmosphere–ocean models have shown that the tropical Atlantic has a significant impact on the Indian monsoon. In this article, the observational basis for this teleconnection is examined and the physical mechanism responsible for bridging sea-surface temperatures (SSTs) in the Atlantic and precipitation over India is investigated with idealized atmospheric general circulation model (AGCM) experiments in which constant SST anomalies are prescribed and ‘switched on’ in the tropical Atlantic region. A simple Gill–Matsuno-type quadrupole response is proposed to explain the teleconnection between the tropical Atlantic and the Indian basin, with an enforcement of the eastward response likely due to nonlinear interactions with the mean monsoon circulation. The simplicity of this mechanism suggests the reproducibility of this result with a broad range of AGCMs. Copyright © 2009 Royal Meteorological Society

This article reviews the level of current scientific understanding regarding the impact of future change in the large-scale climate-earth system on ecosystem services. Impacts from sea level rise, ocean acidification, increases in ocean temperature, potential collapse of the thermohaline circulation; failure of the South Asia monsoon; the melting of sea ice, the Greenland Ice Sheet and the West Antarctic Ice Sheet; changes in water availability; and Amazonia forest dieback, are considered. The review highlights that while a number of uncertainties remain in understanding, there is evidence to suggest that climate change may have already affected some ecosystem services. Furthermore, there is considerable evidence to show that future climate change could have impacts on biodiversity, as well as secondary impacts on issues important to human society, including; habitability; land productivity and food security; water security; and potential economic impacts.

ABSTRACT The Indian Summer Monsoon (ISM) is crucial for agriculture and water resources in India. The large spatial and temporal variability of Indian Summer Monsoon Rainfall (ISMR) leads to flood and drought especially over northern plains of India, so quantitative and qualitative assessment of future projected rainfall will be important for policy framework. Evaluation of models performance in simulating rainfall and wind circulation of the Historical experiment (1961-2005) and its future projected change in RCPs (2006-2050) 4.5 and 8.5 in CMIP5 are carried out. In the Historical experiment, the model simulated rainfall is validated with observed rainfall of IMD (1961-2005) and GPCP (1979-2005) and only six (6) models BCC-CSM1.1(m), CCSM4, CESM1(BGC), CESM1(CAM5), CESM1(WACCM), and MPI-ESM-MR are found suitable in capturing ISMR and JJAS wind circulation at 850 & 200 hPa as in NCEP reanalysis, which shows anticyclonic circulation over Arabian Sea at 850hPa and cyclonic circulation at 200hPa along with excess and deficit rainfall over monsoon regions of NWI, NEI, WCI, CNI and PI at 99% & 95% confidence levels. Future projected change of JJAS wind shows anticyclonic circulation over Arabian Sea at 850hPa and cyclonic circulation around 400N,700E-900E at 200hPa which may be a possible cause of changes in JJAS rainfall over Indian regions.

‘From Pleistocene to Anthropocene: When Rain Dancing and Fire of Agni are Just Not Enough’ The Exhaustive Research Proposal Draft for the 2020 Grant Application for  the VU Distinguished Visiting Fellow in Ethics of the Anthropocene; Religion, Ethics, and Global Environmental Change –‘Geoengineering of Human Death in Asia’: Explorations from the Ancient Human Desire for the Control of Nature to the Present Threat of a Monsoon Breakdown in Asia and the Risk of a Near Future Nuclear Apocalypse No One had Wanted but May Now Have to Face. Includes the Cover Letter Submission from Veli Albert Kallio to Detail Research Interests and Plans for the Fellowship. (The detailed draft of my research proposal [Section 2] has finally uploaded to the Academia.edu web site. Further sections for the proposed research will follow in due course. Overall, the research is still largely a work in progress -  seeking for grants to its various elements - but there are already some important insights that may offer valuable avenues for further investigations from the sections available on this study of Ethnoclimatology, ethics from the past to the present.)

Keynote address for the University of Virginia conference on "Crossings".  Now published in:"China and Beyond in the Medieval Period" edited by Dorothy Wong and Gustav Heldt, Cambria Press, 2014.  The beginning of my study of Maritime Buddhism.

Stable carbon and oxygen isotopic investigations are carried out on planktonic and benthic foraminifera from an AMS-dated sediment core of the northeast Indian Ocean (NEIO) to infer glacial to Holocene changes in surface and deep waters. The chronology of this gravity core (SK157-14; water-depth 3306 m; lat. 5°11'N; long. 90°05'E) was established using six AMS radiocarbon ages and oxygen isotope stratigraphy. Variations in δ18O and δ13C values of planktonic (Globigerinoides ruber) and benthic foraminifera (Cibicidoides spp.) are suggestive of large changes in the surface and deep water characteristics during the last ~ 60 ka. The δ18Opl values in core SK157-14 are significantly higher compared to the sediment cores in the northern Bay of Bengal and the Andaman Sea because of the diminished influence of riverine fresh water fluxes. Large variations in planktonic δ18Opl are noticed during the Marine Isotopic Stage (MIS) 3.1 and 3.3. Glacial to Holocene Δδ18Opl amplitude (1.8‰) is consistent with other published oxygen isotope records from the nearby locations. Maximum enrichment in δ18Opl occurs at 24-19 and the minimum during 7-6 ka BP. Spectral analysis of planktonic δ18Opl time series suggests a teleconnection between surface water δ18O and North Atlantic climate oscillations.

Benthic foraminiferal δ18Oben values indicate deep water cooling of ~ 1.5 °C during the last glacial maximum. The δ13Cben values are generally higher for the Holocene foraminifera suggesting greater contribution from the North Atlantic Deep Water (NADW). However glacial benthic foraminifera are characterized by lower δ13Cben values. Highly depleted δ13Cben values during the ~ 60-50, 21-17 and 13-11 ka BP intervals suggest decrease contribution from the North Atlantic Deep Water (NADW) and increase influx from the Southern Ocean Deep Water (SODW). In addition, oxidation of organic matter and ageing of the deep water may have contributed in the pronounced decrease in δ13Cben during the glacial intervals.

The Indian Summer Monsoon (ISM), a significant part of the global monsoon system, is driven by several climate forcing parameters. With the growing pace of global climate change scenario, there is need to focus on generating more high-resolution records of past monsoon. The ISM reconstructions from Core Monsoon Zone (CMZ) of India, which represents all-India Summer Monsoon Rainfall, are useful for a better understanding of its past variability. Such reconstructions from the CMZ are rather sparse and require detailed study based on various climate proxies. Here, we focus on the reconstruction of ISM variability during the mid-Holocene, based on stalagmite oxygen isotope ratios from the Kotumsar cave, Central India. We show that with decreasing insolation, monsoon started declining at the beginning of the mid-Holocene from 8.5 to 6.5 ka BP, which is also observed in the previous ISM reconstructions with coarser resolutions. However, a gradual increase in the rainfall is observed from 6.5 to 5.6 ka BP, a feature which is also noted in the East Asian Monsoon reconstruction from the Dongge cave. Our record mainly emphasizes on the occurrence of several abrupt weak monsoon events throughout the mid-Holocene. The occurrence of 8.2 and 5.9 ka abrupt weak monsoon events suggest that ISM variability is tightly bound to North-Atlantic Oscillation (NAO). We also demonstrate that ISM during the mid-Holocene was partly sensitive to El-Nino Southern Oscillation (ENSO), and displayed an inverse relationship.

In this essay, I examine Velikovsky's claims, that the Maruts of the Vedic Hymns were meteor storms associated with repeated close approaches of the planet Mars, against the actual wording of his source, and find that he used highly selective quotation to conceal almost all evidence as to the Maruts' true nature as gods of the violent but life-bringing annual monsoon.

Although there is some evidence for an Eocene monsoon the most important intensification of rainfall appears to start ~24 Ma, Early Miocene. Many paleoceanographic proxies for monsoon intensity are linked to wind and do not correlate well with humidity of the continental climate over tectonic timescales. Rainfall peaked in the middle Miocene (~15 Ma) with strong drying after 8 Ma. This timing does not correlate well with either initial uplift of the Tibetan Plateau or with the retreat of shallow seas from central Asia. The ~24 Ma onset of strengthening rainfall is associated with initiation of rapid erosion and cooling of Himalayan metamorphic rocks. The progressive detachment of the subducting Indian lithosphere from the eastern and western syntaxes at ~25 Ma to the east-central Himalaya at ~13–11 Ma would have produced corresponding propagation of rising Himalayan topography following release of the weight of the detached slab. Rapid uplift of the Himalayan barrier, blocking moisture-laden winds is considered the most likely trigger for a stronger summer monsoon in South Asia, which in turn allowed faster erosion and exhumation of the Greater Himalaya after 24 Ma.

Here we present the first record of Sr/Ca variability in a massive Porites lutea coral from the Lakshadweep Archipelago, Arabian Sea. The annual mean sea surface temperature (SST) in this region and the surrounding areas has increased steadily in the recent past. During some major El Ni~ no events, SSTs are even higher, imposing additional thermal-stress on corals, episodically leading to coral bleaching. We infer from the coral-Sr/Ca record (1981–2008) that during some of these events high and persistent SSTs lead to a dampening of the temperature signal in coral-Sr/Ca, impairing the coral's ability to record full scale warming. Thus, coral-Sr/Ca may provide a history of past El Ni~ no Southern-Oscillation (ENSO) induced thermal-stress episodes, which are a recurrent feature also seen in cross-spectral analysis between coral-Sr/Ca and the Nino3.4 index. Despite the impact of episodical thermal-stress during major El Ni~ no events, our coral proxy faithfully records the seasonal monsoon-induced summer cooling on the order of 2.38C. Calibration of coral-Sr/Ca with instrumental grid-SST data shows significant correlation to regional SST and monsoon variability. Hence, massive Porites corals of this region are highly valuable archives for reconstructing long-term changes in SST, strongly influenced by monsoon variability on seasonal scales. More importantly, our data show that this site with increasing SST is an ideal location for testing the future effects of the projected anthropogenic SST increase on coral reefs that are already under thermal-stress worldwide.

Clay minerals from the Indus Canyon and eastern clinoform since ∼12 ka are uniformly rich in smectite and illite, similar to those from the Holocene Indus flood plains. A systematic enrichment of smectite in the proximal delta compared to the canyon and eastern clinoform argues for preferential capture of smectite close to the river mouth since ∼12 ka. There is a rapid shift to a more smectite-rich assemblage in the canyon and eastern clinoform after ∼5 ka. This change is probably caused by a change in sediment source, with less direct flux from the Himalaya and more erosion of older, weathered, smectite-rich sediment from the Indus River flood plains, driven by incision of the Indus and its tributaries into the floodplain as summer monsoon rains weakened. This influx of smectite is consistent with lower kaolinite/smectite values since ∼5 ka. The onset of large-scale agricultural activities since ∼5 ka, especially starting with the Harappan Civilization, may also have enhanced incision and erosion of floodplain sediments over the same time period. This study reports for the first time how monsoon strength variations since ∼12 ka affected the clay mineral assemblages and sediment provenance in a major submarine canyon.

See https://rdcu.be/bJgE0

The rise of ammonia emissions in Asia is predicted to increase radiative cooling and air pollution by forming ammonium nitrate particles in the lower troposphere. There is, however, a severe lack of knowledge about ammonia and ammoniated aerosol particles in the upper troposphere and their possible effects on the formation of clouds. Here we employ satellite observa-tions and high-altitude aircraft measurements, combined with atmospheric trajectory simulations and cloud-chamber experi-ments, to demonstrate the presence of ammonium nitrate particles and also track the source of the ammonia that forms into the  particles. We found that during the Asian monsoon period, solid ammonium nitrate particles are surprisingly ubiquitous in the upper troposphere from the Eastern Mediterranean to the Western Pacific—even as early as in 1997. We show that this ammo-nium nitrate aerosol layer is fed by convection that transports large amounts of ammonia from surface sources into the upper troposphere. Impurities of ammonium sulfate allow the crystallization of ammonium nitrate even in the conditions, such as a high relative humidity, that prevail in the upper troposphere. Solid ammonium nitrate particles in the upper troposphere play a hitherto neglected role in ice cloud formation and aerosol indirect radiative forcing.

Simulation of Indian Summer Monsoon (ISM) onset over South Asia Coordinated Regional Climate Downscaling Experiment (CORDEX) domain in pentad composite pattern is considered for this study. The latest version of the International Center for Theoretical Physics' (ICTP's) Regional Climate Model version 4.3 (RegCM-4.3) is used for the simulation of a pentad composite onset for three time period: Pre-onset, Onset and Post-onset periods of ISM. Each pentad composite is average of five consecutive days. 10 years (2001–2010) worth of pentad composites of rainfall, mean sea level pressure (MSLP), outgoing longwave radiation (OLR), wind at 850 hPa and 925 hPa levels till 7 days prior to the date of onset of monsoon and 7 days after the onset are analyzed to find out the predictive skill. Six Parameterization convection schemes (PCSs) viz. Kuo, Mix98, Mix99, Tiedtke, Emanuel and Grell are used in sensitivity experiment and estimation of their performance has been done. From the experiment, some modulation is found in the OLR field (≤ 200 Wm− 2) within the region 5°N–10°N and 70°N–75°E. Yearly analysis has shown the strength of wind at 925 hPa over the region 5°N–10°N and 70°E–80°E on pentad composite onset of ISM. Yearly analysis is conducted for finding the best fitted PCS which has provided the precursor for simulating the onset.

The Ifaty coral record from off SW Madagascar provide a 336-year coral oxygen isotope record that is used to investigate the natural variability of the western Indian Ocean subtropical SST dipole and ENSO. The coral oxygen isotope record primarily reflects past sea-surface temperature (SST) variability on seasonal to multidecadal scales. To validate the SST reconstructions derived from oxygen isotopes, Sr/Ca ratios were obtained for selected time windows (1973–1995, 1863–1910, 1784–1809, 1688–1710). The period 1675–1760 was found to be the coolest period of the entire record with anomalies of 0.3–0.5 °C that includes the Late Maunder Minimum (1675–1710). The warmest periods, as indicated by our data, occur between 1880 and 1900 and the upper part of the Ifaty record (1973–1995).We generated a time series of coral δ18O for different seasons of the year to investigate austral winter and summer SST variability that influences rainfall intensity over southern Africa. Winter coral δ18O is coherent with winter SST on decadal and multidecadal time scales between 1854 and 1995. We suggest that the Ifaty winter time series provides a record of winter SST variability over the Mozambique Channel/Agulhas Current region over 336 years.Strong Indian Ocean subtropical dipole events, occurring during austral summer, are displayed in the Ifaty record. The austral summer coral δ18O is coherent and in phase with ENSO indices on interannual time scales (2–4 years) between 1880–1920, 1930–1940 and after 1970. Our data indicate that the impact of ENSO on SW Indian Ocean SST and atmospheric circulation was also strong between 1680–1720 and 1760–1790, in agreement with other studies. We show evidence that these variations are caused by changes in the regional hydrologic balance. The results demonstrate that the impact of ENSO cycles in the region of the SW Indian Ocean has changed significantly since 1970 and relate to a warming of southwestern Indian Ocean surface waters altering the spatial signature of ENSO.

Climate model faces considerable difficulties in simulating the rainfall characteristics of southwest summer monsoon. In this study, the dynamical downscaling of European Centre for Medium-Range Weather Forecast's (ECMWF's) ERA-Interim (EIN15) has been utilized for the simulation of Indian summer monsoon (ISM) through the Regional Climate Model version 4.3 (RegCM-4.3) over the South Asia CoOrdinated Regional Climate Downscaling EXperiment (CORDEX) domain. The complexities of model simulation over a particular terrain are generally influenced by factors such as complex topography, coastal boundary, and lack of unbiased initial and lateral boundary conditions. In order to overcome some of these limitations, the RegCM-4.3 is employed for simulating the rainfall characteristics over the complex topographical conditions. For reliable rainfall simulation, implementations of numerous lower boundary conditions are forced in the RegCM-4.3 with specific horizontal grid resolution of 50 km over South Asia CORDEX domain. The analysis is considered for 30 years of climatological simulation of rainfall, outgoing longwave radiation (OLR), mean sea level pressure (MSLP), and wind with different vertical levels over the specified region. The dependency of model simulation with the forcing of EIN15 initial and lateral boundary conditions is used to understand the impact of simulated rainfall characteristics during different phases of summer monsoon. The results obtained from this study are used to evaluate the activity of initial conditions of zonal wind circulation speed, which causes an increase in the uncertainty of regional model output over the region under investigation. Further, the results showed that the EIN15 zonal wind circulation lacks sufficient speed over the specified region in a particular time, which was carried forward by the RegCM output and leads to a disrupted regional simulation in the climate model.

δ18O measurements in surface dwelling planktonic foraminifera (PF) Globigerinoides (Gs.) ruber from a sediment core from the central Bay of Bengal (BOB) has recorded a gradual depletion from ~ -1‰ during Last Glacial Maximum (LGM) to ~ -3‰ during mid-Holocene suggesting a strengthening of Indian Summer Monsoon (ISM) over the bay during last glacial - interglacial transition. However, this trend is punctuated by abrupt multi-centennial enrichment in the δ18O values of the order of ~ 0.5 ‰. Age model of the core obtained from AMS 14C dates in mixed planktonic foraminifera and in bulk sediment suggests that timing of these abrupt enrichments of the δ18O values corresponds to the Heinrich (H1), Younger Dryas (YD) and 8.2 ka North Atlantic cold events centered at ~ 15.5 cal ka BP, 11.7 cal ka BP and 8 cal ka BP respectively. It is also observed that although there are episodes of significant changes in the sea surface temperature and salinity (as reflected in the periodical enrichment in the δ18O values) between 19ka to 5ka, the abundance of the mixed layer PF - Gs. ruber and Gs. sacculifer - and upper thermocline dweller Neogloboquadrina dutertrei do not show much variation during this period indicating that the upper ocean stratification remained almost same in the bay after the major turnover at the end of LGM. This suggests that this periodical enrichment of δ18O in the surface dwelling PF Gs. ruber is controlled primarily by the episodes of abrupt monsoon decline. The synchrony of cold events of NGIRP ice core and North Atlantic marine records with the central BOB core suggests the existence of a strong tele-connection between the North Atlantic and the monsoon variability as recorded in BOB sediments. We propose that northern hemispheric abrupt cold events like H1, YD and 8.2 ka recorded in the Greenland and the North Atlantic had played a vital role in modulating the ISM over the bay and thus giving rise to a stepwise strengthening of ISM during the last glacial-interglacial transition in the BOB

The South Asian Monson (SAM) is one of the most intense climatic elements yet its initiation and variations are not well established. Dating the deposits of SAM wind-driven currents in IODP cores from the Maldives yields an age of 12. 9 Ma indicating an abrupt SAM onset, over a short period of 300 kyrs. This coincided with the Indian Ocean Oxygen Minimum Zone expansion as revealed by geochemical tracers and the onset of upwelling reflected by the sediment&#39;s content of particulate organic matter. A weaker &#39;proto-monsoon&#39; existed between 12.9 and 25 Ma, as mirrored by the sedimentary signature of dust influx. Abrupt SAM initiation favors a strong influence of climate in addition to the tectonic control, and we propose that the post Miocene Climate Optimum cooling, together with increased continentalization and establishment of the bipolar ocean circulation, i.e. the beginning of the modern world, shifted the monsoon over a threshold towards the modern system.

Purpose of the study: The purpose of this present study was to determine the concentration of chloride ions in the water sample which collected different sites and seasons of river Ganga. Chloride ions in the environment can come from sodium chloride or from other chloride salts such as potassium chloride, calcium chloride and magnesium chloride. Methodology: Water sample was collected from different sites (Bithor ghat,  Siddnath ghat and  Dhoni ghat)  and different seasons (Pre-monsoon,  Monsoon and post-monsoon)  of river  Ganga from  Kanpur in the 2016-2018  year. Mohr method (Argentometric method)  was a  very simple and highly selective method for the determination of chloride ion  (Cl-)  using silver nitrate as the titrant.
Main Findings: In both the years 2016 till 2018, chloride concentration was within the limit at testing sites.
Applications of this study: To create awareness among the people to maintain the Ganga river water at its highest quality and purity levels.
Originality: This project was done in the D G PG College C S J M University, Kanpur India.

To study the ecology of calcareous dinoflagellates we examined the impact of the SW and NE monsoons on cyst formation using sediment trap material, collected at 1032 m water depth, off Somalia from June 1992 to February 1993. The results do not confirm the relationship between cyst production and lower nutrient concentrations, as highest cyst fluxes were recorded during late SW monsoon under the relatively nutrient-rich and less agitated conditions of mature upwelled water. Lowest cyst fluxes were found under strongly stratified, nutrient-depleted surface waters during the inter-monsoon. Although all of the studied species seem to prefer a stratified water column, an elevated concentration of nutrients appears to be necessary to maintain high cyst production. Comparison of the mean cyst flux to the sediment trap with that into the underlying surface sediments reveals a loss of 81-96%, which can be attributed to calcite dissolution. The relatively small spheres of Thoracosphaera heimii are affected more than the cysts of the other species.