Variations in petrography, stable isotopes, reflectance, and luminescence along the central growth axis of a 14.5cm stalagmite from Panigarh cave indicate cooler and slightly wetter conditions in the Himalayan foothills of northern India during the Little Ice Age (LIA), which lasted from ~AD 1489-1889 based on deposition of calcite, and AD 1450-1820 based on rapid changes in δ18O values. Conditions were warmer and drier during the preceding Medieval Climate Anomaly (MCA) and also in the post-LIA periods, as evidenced by deposition of aragonite. A review of currently existing stalagmite and other proxy data from south and east Asia reveals a broad spatial pattern in precipitation over south and east Asia during the LIA, with northern areas showing generally increased precipitation and southern areas reduced precipitation. During the MCA and after the LIA, the records suggest this pattern was reversed. Weaker ISM during the LIA brought drought conditions to the core ISM area but triggered more monsoon 'breaks' that brought higher precipitation to the Himalayas. At the same time, the weaker ISM may also have pushed more depressions along the path of the southern winter jet which brought more winter precipitation to the Himalayas and therefore a LIA wetter in our study area.
Bibliographical noteFunding Information:
This research was supported by a DDR NSF grant 0623407 to Brook and Liang and by funds provided to Brook by the Franklin College of Arts and Sciences, University of Georgia . Kotlia is grateful to the Alexander von Humboldt Foundation (Linkage Project, No 3-4-FoKoop, 396 DEU/1017420) and Ministry of Earth Sciences (MoES/PO/Geosci/43/2015, New Delhi) for financial support and Kandasamy thanks the National Science Foundation of China (No. 41273083 ), Shanhai Fund (No. 2013SH012 ) and Open Fund of Tongji University, China (No. MGK1201 ) for the financial support.
- Indian Summer Monsoon
- Little Ice Age
- Medieval Climate Anomaly
- Monsoon breaks