noaa-cave-12912 Mawmluh Cave, India Holocene Stalagmite d18O Data Berkelhammer, M.B.; Sinha, A.; Stott, L.D.; Cheng, H.; Pausata, F.; Yoshimura, K. Mawmluh Cave, India Holocene Stalagmite d18O Data 2012-05-17 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/12912 Investigator M.B. Berkelhammer Investigator A. Sinha Investigator L.D. Stott Investigator H. Cheng Investigator F. Pausata Investigator K. Yoshimura earth science paleoclimate speleothems age,null,null,calendar year before present,null,speleothems,null,null,N,null earth science paleoclimate speleothems delta 18O,calcium carbonate,null,per mil VPDB,null,speleothems,raw,isotope ratio mass spectrometry,N,null earth science paleoclimate speleothems oxygen isotopes geoscientificInformation Monsoon 12395 cal yr BP 3653 cal yr BP Complete 25.2622 25.2622 91.8167 91.8167 1290 1290 Continent Asia Southcentral Asia India Mawmluh Cave>LATITUDE 25.2622>LONGITUDE 91.8167 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Berkelhammer, M., A. Sinha, L. Stott, H. Cheng, F. Pausata, and K. Yoshimura 2012 Geophysical Monograph Series 10.1029/2012GM001207

The emergence of high-resolution proxy records from the Asian Monsoon region suggest that the monsoon system is bistable and can abruptly transition between a suppressed and active state. This observation is critical in considering how the monsoon system may have influenced the development of societies across South and East Asia during the Holocene. Using a new high-resolution (~5 years/sample) speleothem stable isotope record from Northeast India that spans the early and mid- Holocene, a number of abrupt changes in the oxygen isotopic composition of precipitation (d18O) are documented. The most dramatic of these events occurred ~4,000 years ago when, over the course of approximately a decade, isotopic values abruptly rose above any seen during the early to mid Holocene and remained at this anomalous state for almost two centuries. This event occurs nearly synchronously with climatic changes documented in a number of proxy records across North Africa, the Middle East, the Tibetan Plateau, Southern Europe and perhaps as far as North America. The changes in d18O were likely driven by a dynamic response of the Indian Summer Monsoon (ISM) to changes in surface heating on the Tibetan Plateau and/or to large-scale ocean dynamics in the Indian Ocean Basin. At this point, a quantitative characterization of the change in the ISM is hindered by unconstrained aspects of the regional response of d18O to climate, but we hypothesize the excursion could represent a shift towards an earlier monsoon withdrawal, a more northerly vapor source region or a general decline in the total amount of monsoon precipitation. The new record provides a very significant advance with respect to age control and sample resolution of terrestrial climate change over South Asian during this period when a number of major societal changes occurred. While evidence of a causal relationship between climate and the re-organization of the Indus Valley and Old Kingdom Nile civilizations is beyond the scope of this study, the tight age constraints of the record show with a high degree of certainty that much of the documented de-urbanization of the Indus Valley at 3.9k yr BP occurred after multiple decades of a shift in the monsoon's character but before the monsoon returned to its previous mid-Holocene state. STUDY NOTES: d18O from a calcitic stalagmite (KM-A) from Mawmluh Cave, located in Cherrapunji, Meghalaya in northeast India. Dating is based on 8 U/Th series dates, which are described in the publication text. Mawmluh Cave, India: 25°15'44"N, 91°52'54"E, 1290m elevation.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2012.xls GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2012.txt USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11