A review on Holocene climate changes in Indian subcontinent
IR@NIO: CSIR-National Institute Of Oceanography, Goa
View Archive Info| Field | Value | |
| Creator |
Naidu, P.D.
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| Date |
2009-01-10T11:15:55Z
2009-01-10T11:15:55Z 1999 |
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| Identifier |
Memoir of the Geological Society of India, Vol.42; 303-314p.
http://drs.nio.org/drs/handle/2264/1782 |
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| Description |
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 Circulation Model (GCM) experiments show that onset of monsoon is related to the Himalayan Mountain elevation. Near 8 Ma, the relative abundance of endemic upwelling species increases and is interpreted to reflect the intensification and onset of the strong modern monsoon circulation. Oxygen isotope data from the sediment cores of the Arabian Sea indicates that the onset of Holocene climate started around 13 ka in the Indian subcontinent. The summer monsoon intensification was initiated from 12 ka after a weak phase during the last glacial maximum. Higher lake levels and greater values of upwelling indices between 9 to 6 ka reflect the intense phase of monsoon rainfall. Pollen records from lake sediments in Rajasthan also reveal greater rainfall during 9 to 6 ka. Marine and terrestrial records document that the climate started shifting from humid to dry arid from 5 ka and reached an arid phase at 3.5 ka. In other tropics of the world also onset of arid climate was documented during the same period. The onset of arid climate at 3.5 ka in the Indian subcontinent might be responsible for weak summer monsoon rainfall. Drastic reduction in rainfall could have led to the collapse of Indus Valley Civilization and desiccation of River Holocene Chronology with special reference to Indian subcontinent is proposed by synthesizing available marine, lacustrine, pollen and archaeological records
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| Language |
en
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| Publisher |
Geological Society of India
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| Rights |
Copyright [1999]. All efforts have been made to respect the copyright to the best of our knowledge. Inadvertent omissions, if brought to our notice, stand for correction and withdrawal of document from this repository.
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| Subject |
palaeoclimate
climatic changes holocene indicators monsoons oxygen isotopes plankton |
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| Title |
A review on Holocene climate changes in Indian subcontinent
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| Type |
Journal Article
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