Articles | Volume 22, issue 2
https://doi.org/10.5194/cp-22-427-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-22-427-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
02 Mar 2026
Research article |
| 02 Mar 2026
| 02 Mar 2026
Drivers of the δ18O changes in Indian Summer Monsoon precipitation between the Last Glacial Maximum and pre-industrial period
Interdisciplinary Centre for Water Research, Indian Institute of Science, Bengaluru 560012, India
Govindasamy Bala
Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bengaluru 560012, India
Jesse Nusbaumer
National Center for Atmospheric Research, Boulder, USA
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Short summary
During the Last Glacial Maximum (LGM), the Indian monsoon rainfall was 15 % lower than the pre-industrial period due to global cooling and changes in atmospheric circulation. The isotopic composition of rainfall, more positive during the LGM, is not directly linked to the rain amount. It is influenced by a reduced contribution of moisture from distant sources and less rainouts during transport from the Indian Ocean. Hence, Isotopic proxies may be better indicators of atmospheric circulation.
During the Last Glacial Maximum (LGM), the Indian monsoon rainfall was 15 % lower than the...
