Browsing by Subject "palaeoclimate"
Now showing items 1-20 of 43
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A review on Holocene climate changes in Indian subcontinent
(Geological Society of India, 1999)Since the collision of Indian plate with Eurasia, the Indian subcontinent has experienced minor tectonic and major climatic changes. Summer monsoon plays an important role in the local and regional climate of Asia. General ... -
Boron/calcium ratios in Globigerinoides ruber from the Arabian Sea: Implications for controls on boron incorporation
(Elsevier, 2014)Culture and downcore studies have been used to argue that B/Ca ratios in planktic foraminifera are correlated with seawater pH and may record seawater borate/bicarbonate ratios, although other factors may also control B/Ca. ... -
Buried nodules from the central Indian Ocean basin
(Regional Research laboratory, Bhubaneswar, 2005)The occurrence of buried nodules is rare compared to surface nodule abundance in the deep sea. Surface nodules are collected with freefall grab, vanveen /peterson grabs, dredges and sediment cores whereas buried nodules ... -
Carbon and oxygen isotope time series records of planktonic and benthic foraminifera from the Arabian Sea: Implications on upwelling processes
(Elsevier, 2003)Oxygen and carbon isotopic analyses have been performed on the tests of Globigerina bulloides and Pulleniatina obliquiloculata (planktonic foraminifera) and Uvigerina excellens (benthic foraminifer) to study the evolution ... -
Climatic aridity over India 11,000 years ago: Evidence from feldspar distribution in shelf sediments
(Elsevier, 1986)Feldspars and quartz contents of sand and silt fractions of forty three samples from the western continental shelf of India were determined by the X-ray diffraction method. The results indicate that the feldspar content ... -
Deglaciation in the tropical Indian Ocean driven by interplay between the regional monsoon and global teleconnections
(Elsevier, 2013)High resolution climate records of the ice age terminations from monsoon-dominated regions reveal the interplay of regional and global driving forces. Speleothem records from Chinese caves indicate that glacial terminations ... -
Equatorial Indian Ocean productivity during the last 33 kyr and possible linkage to Westerly Jet variability
(Elsevier, 2014)The top 1 m radiocarbon dated section of a 5.6 m long sediment core retrieved from the Equatorial Indian Ocean is studied for productivity changes in response to climate variability that have taken place during the last ... -
Evidences of climatic variations during Late Pleistocene- Holocene in the eastern Bay of Bengal
(Current Science Association, Bangalore, India, 1993)Based upon the variations of clay minerals, sediment texture, heavy mineral assemblage and sup(230)Th excess in the Late Pleistocene sediments of a hemipelagic core from the eastern Bay of Bengal (2713 m water depth), 35 ... -
Fluctuating monsoonal precipitation as revealed by foraminiferal variations in a core from shelf regime off Karwar (India)
(Current Science Association, 1988)Variations in the percentage frequency of the foraminifera Cavarotalia annectens in the sediments collected by box core in the shelf region of Karwar, infront of the mouth of the Kalinadi river, India were used to map ... -
Foraminifera as climatic indicators in the sediments of Western Indian continental shelf
(Indian Association for Limnology and Oceanography, 1973)Foraminifera are the single celled microscopic organisms found abundantly in the seas and oceans. The tests of these organisms are preserved in the present sediments of the ocean as in the past, sometimes constituting ... -
Glacially derived material in an Inner Mongolian desert lake during Marine Isotope Stage 2
(John Wiley, 2012)Establishing the precise timing of continental glacial dynamics and abrupt high-latitude climate events is crucial to understanding the causes of global climate change. Multi-proxy records in a lake sediment core from arid ... -
High resolution climate reconstructions of recent warming using instrumental and ice core records from coastal Antarctica
(India Meteorological Department, 2011)In-situ observational record of Antarctic surface temperatures is rather sparse. Proxy based ice core studies are thus critical for reconstructing the past climate change on centennial and decadal time scales. The present ... -
High resolution climatic records of the past ~489 years from Central Asia as derived from benthic foraminiferal species, Asterorotalia trispinosa
(Elsevier, 2012)Many researchers have reported the occurrence of the species Asterorotalia trispinosa as a major constituent in foraminiferal assemblages from different regions, its ecological significance has never been studied. The ... -
Inorganic combined nitrogen budget of the Arabian Sea: Some geochemical and climatic implications
(Waseda University, Tokyo, 1992)Estimates of the local sources and sinks of inorganic combined nitrogen in the Arabian Sea suggest a net loss of sup(-)3 x 10 sup(13) gN y sup(-1). This seems to be made up largely by the upward flux facilitatEd. by a high ... -
Late Quaternary Halimeda bioherms and aragonitic faecal pellet-dominated sediments on the carbonate platform of the western continental shelf of India
(Elsevier, 1994)The Fifty Fathom Flat is a drowned carbonate platform located on the outer continental shelf of western India. It unique because the carbonate depositional environment prevailed until Early Holocene in spite of its proximity ... -
Late Quaternary paleoceanographic features as deduced from calcium carbonate and faunal changes of planktonic foraminifers in core samples from northeastern Arabian Sea
(Marine Biological Association of India, 1997)Two pelagic core samples, ARB-52 and ARB-54 from 2240 m and 800 m depths respectively from the Arabian Sea off Bombay were analysed for determining climatic changes during the past 30,000 yr. based on the interpretation ... -
Late-Quaternary variations in clay minerals along the SW continental margin of India: Evidence of climatic variations
(Springer, 2000)Down-core variations in illite, chlorite, smectite and kaolinite (the major clays) in two sup(14)C-dated cores collected along the SW continental margin of India show that illite and chlorite have enhanced abundance during ... -
Mean proloculus size, delta super(13) C and delta super(18) O variations in recent benthic foraminifera from the west coast of India and their climatic implications
(Indian Society of Earth Sciences, Calcutta, 1993)The interrelationship between mean proloculus size (MPS), delta super(18) O and delta super(13) C vatiations in benthic foraminiferal species Rotalidium annectens and their relation with temperature (T) and salinity (S) ... -
Models for changes in atmospheric carbon dioxide, ocean geochemistry and circulation during the late Pleistocene
(Vikas Publication, 1990)This report provides a review of various hypotheses put forward so far as to the role of the oceans in controlling the glacial-interglacial climatic cycles through controls on the atmospheric carbon dioxide. The available ... -
Monsoon related changes in sea surface productivity and water column denitrification in the Eastern Arabian Sea during the last glacial cycle
(Elsevier, 2005)Sea surface salinity reconstruction for the Holocene and the Last Glacial Maximum (LGM) suggests that the LGM-Eastern Arabian Sea was more saline (by approx.5 psu) than the Holocene due to weakened freshwater flux to the ...