Interannual to centennial variability of the South Asian summer monsoon over the past millennium

noaa-recon-22730 South Asian Summer Monsoon Index 1105 Year Reconstruction Shi, F.; Fang, K.; Xu, C.; Guo, Z.; Borgaonkar, H.P. South Asian Summer Monsoon Index 1105 Year Reconstruction 2017-10-01 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/22730 Investigator F. Shi Investigator K. Fang Investigator C. Xu Investigator Z. Guo Investigator H.P. Borgaonkar earth science paleoclimate climate reconstructions|tree ring age,null,null,year Common Era,null,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring South Asian Summer Monsoon Index,null,null,dimensionless,Jun-Sep,climate reconstructions|tree ring,null,null,N,optimal information extraction (OIE1.0) earth science paleoclimate climate reconstructions|tree ring South Asian Summer Monsoon Index,null,unspecified error lower bound,dimensionless,Jun-Sep,climate reconstructions|tree ring,null,null,N,optimal information extraction (OIE1.0) earth science paleoclimate climate reconstructions|tree ring number of samples,null,null,count,null,climate reconstructions|tree ring,null,null,N,number of tree-ring predictor samples earth science paleoclimate climate reconstructions|tree ring South Asian Summer Monsoon Index,null,unspecified error upper bound,dimensionless,Jun-Sep,climate reconstructions|tree ring,null,null,N,optimal information extraction (OIE1.0) earth science paleoclimate instrumental South Asian Summer Monsoon Index,null,null,dimensionless,Jun-Sep,instrumental,null,null,N,null earth science paleoclimate reconstructions atmospheric circulation earth science paleoclimate reconstructions precipitation geoscientificInformation Atmospheric and Oceanic Circulation Patterns Reconstruction Monsoon 896 AD 2000 AD 1054 cal yr BP -50 cal yr BP Complete 5 22.5 35 97.5 Continent Asia Southern Asia South Asia>LATITUDE >LONGITUDE 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 Feng Shi, Keyan Fang, Chenxi Xu, Zhengtang Guo, H.P. Borgaonkar 2017 Interannual to centennial variability of the South Asian summer monsoon over the past millennium Climate Dynamics 49 7-8 2803-2814 10.1007/s00382-016-3493-9 https://link.springer.com/article/10.1007%2Fs00382-016-3493-9 Feng Shi, Jianping Li, and Rob J. S. Wilson 2014 A tree-ring reconstruction of the South Asian summer monsoon index over the past millennium Scientific Reports 6739 4 10.1038/srep06739 http://www.nature.com/srep/2014/141023/srep06739/full/srep06739.html

The South Asian summer monsoon (SASM) is a major atmospheric synoptic climate system affecting nearly a quarter of the human population. Climate proxy data derived from tree rings, ice cores, speleothems, and other sources can all contribute to an understanding of SASM variability prior to instrumental period. Here, we develop an optimal information extraction (OIE) method, which we use to reconstruct the SASM index (SASMI) over the last millennium using 15 tree-ring chronologies. The record generated is significantly correlated (r = 0.7, p < 0.01) with the instrumental SASMI record on annual timescales; this correlation is higher than that obtained in any previous study. The reconstructed SASMI captures 18 of 26 (69%) reordered historical famine events in India over the last millennium; notably, 11 of 16 short events with durations of 1-3 years are accurately depicted in our reconstruction. Moreover, the reconstructed SASMI is positively correlated with variations in total solar irradiance (TSI) on multi-decadal timescales implying that variations in solar activity may influence the SASM. Based on the response of SASM to 34 significant volcanic events using the superposed epoch analysis, the volcanic forcing may drive a weak SASM in the second year of an eruption. STUDY NOTES: Tree-ring based reconstruction of the South Asian Summer Monsoon Index (SASMI) for the past 1,105 years. This is an updated version of the Shi et al. 2014 SASMI reconstruction (https://www.ncdc.noaa.gov/paleo/study/17369), utilizing an expanded set of 23 tree-ring predictors (8 additional tree-ring series from India).

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/asia/shi2017sasmi.txt Formatted Text Data File; South Asian Summer Monsoon Index Reconstruction USA/NOAA DIF Version 9.8.4 2019-02-19 2019-02-19