Mawmluh Cave, India 50 Year Speleothem d18O and Trace Element Data Ronay, E.R.; Breitenbach, S.F.M.; Oster, J.L.; Myers, C.G.; Kelley, N.P.; Covey, A.K.; Bennartz, R. Ronay, E.R. Breitenbach, S.F.M. Oster, J.L. Myers, C.G. Kelley, N.P. Covey, A.K. Bennartz, R. Monsoon earth science/paleoclimate/speleothems earth science/paleoclimate/speleothems (Mawmluh Cave>LATITUDE 25.2622>LONGITUDE 91.8167) In climates with strongly seasonal rainfall, speleothem-based paleoclimate reconstructions are often thought to reflect wet season conditions, assuming a bias toward the season with greater water supply. This is particularly true in monsoon regions, where speleothem records are interpreted to document monsoon strength changes on multiple timescales. Dry season infiltration variability and rainfall seasonality are not typically considered in these reconstructions, even though cave ventilation could bias speleothem growth toward the cooler season. To investigate the influence of dry season infiltration on speleothem geochemistry, we combine a modern, sub-seasonally resolved trace element record from Mawmluh Cave in Northeast India with forward modeling experiments. We find that variations in the amplitude of seasonal signals in speleothem Mg/Ca, which reflects prior carbonate precipitation, are more sensitive to dry season rather than monsoon season infiltration. This sensitivity may be enhanced by dry season cave ventilation. The Mawmluh speleothem Mg/Ca record is consistent with increased dry season rainfall during the 1976-1998 warm phase of the Pacific Decadal Oscillation relative to 1964-2013. Our work demonstrates the importance of considering non-monsoon season rainfall when interpreting speleothem paleoclimate records and suggests that trace elements could provide insight into periods of enhanced dry season infiltration in monsoonal climates. STUDY NOTES: Trace element ratios (Mg/Ca, Sr/Ca, Ba/Ca, U/Ca) and oxygen isotope (d18O) data at sub-seasonal resolution from stalagmite MAW-0201 collected in Mawmluh Cave, India, for the past 50 years NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Ronay, E.R. Investigator : Breitenbach, S.F.M. Investigator : Oster, J.L. Investigator : Myers, C.G. Investigator : Kelley, N.P. Investigator : Covey, A.K. Investigator : Bennartz, R. 2019-03-25 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/26470 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2019elem.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2019d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2019elem.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2019d18o.txt English https://www.ncdc.noaa.gov/paleo/study/26470 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2019elem.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2019d18o.txt Elli R. Ronay, Sebastian F.M. Breitenbach, Jessica L. Oster2019Sensitivity of speleothem records in the Indian Summer Monsoon region to dry season infiltrationScientific Reports91509110.1038/s41598-019-41630-2www.nature.com/articles/s41598-019-41630-2 Christopher G. Myers, Jessica L. Oster, Warren D. Sharp, Ralf Bennartz, Neil P. Kelley, Aaron K. Covey, Sebastian F.M. Breitenbach2015Northeast Indian stalagmite records Pacific decadal climate change: Implications for moisture transport and drought in IndiaGeophysical Research Letters42104124-413210.1002/2015GL063826https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015GL063826 START YEAR: 1964 AD * END YEAR: 2013 AD 91.8167 25.2622 91.8167 25.2622