Indo-Pacific Warm Pool Last Glacial Maximum Hydroclimate Proxy Synthesis DiNezio, P.N.; Tierney, J.E. DiNezio, P.N. Tierney, J.E. Last Glacial Maximum Other Hydroclimate Reconstruction Warm Pool hydrology earth science/paleoclimate/climate reconstructions (notes,null,null,null,null,climate reconstructions,null,null,C,Proxy) earth science/paleoclimate/climate reconstructions (number of samples,null,null,count,null,climate reconstructions,null,null,N,number of observations) earth science/paleoclimate/climate reconstructions (notes,null,null,null,null,climate reconstructions,null,null,C,reference) earth science/paleoclimate/climate reconstructions (notes,null,null,null,null,climate reconstructions,null,null,N,"whether the observations merged into each ""gridded"" point agree (is_robust=1) or not (is_robust=0)") earth science/paleoclimate/climate reconstructions (moisture index,multiple proxies,null,dimensionless,null,climate reconstructions,null,null,N,"""KEY: -1 = Drier, 0 = No Change, 1 =Wetter""") earth science/paleoclimate/climate reconstructions (longitude,null,null,degree east,null,climate reconstructions,null,null,N,null) earth science/paleoclimate/climate reconstructions (salinity,multiple proxies|sea surface,null,dimensionless,null,climate reconstructions,null,null,N,"""KEY: -1 = Fresher, 0 = No Change, 1 = Saltier""") earth science/paleoclimate/climate reconstructions (latitude,null,null,degree north,null,climate reconstructions,null,null,N,null) earth science/paleoclimate/climate reconstructions (notes,null,null,null,null,climate reconstructions,null,null,N,"""chrono_flag=1"" indicates whether the proxy record contains one or more radiocarbon U/Th or well-constrained OSL dates near to or during the LGM. chrono_flag=0 indicates that the LGM was dated via wiggle-matching the local benthic d18O to a global stack or another method.") earth science/paleoclimate/climate reconstructions (sample identification,null,null,null,null,climate reconstructions,null,null,C,location plus core ID) earth science/paleoclimate/reconstructions (Indo-Pacific Warm Pool>LATITUDE >LONGITUDE ) The Indo-Pacific warm pool - the main source of heat and moisture to the global atmosphere - plays a prominent role in tropical and global climate variability. During the Last Glacial Maximum, temperatures within the warm pool were cooler than today and precipitation patterns were altered, but the mechanism responsible for these shifts remains unclear. Here we use a synthesis of proxy reconstructions of warm pool hydrology and a multi-model ensemble of climate simulations to assess the drivers of these changes. The proxy data suggest drier conditions throughout the centre of the warm pool and wetter conditions in the western Indian and Pacific oceans. Only one model out of twelve simulates a pattern of hydroclimate change similar to our reconstructions, as measured by the Cohen's K statistic. Exposure of the Sunda Shelf by lower glacial sea level plays a key role in the hydrologic pattern simulated by this model, which results from changes in the Walker circulation driven by weakened convection over the warm pool. We therefore conclude that on glacial-interglacial timescales, the growth and decay of ice sheets exert a first-order influence on tropical climate through the associated changes in global sea level. STUDY NOTES: Synthesis of hydroclimatic proxy records for the Indo-Pacific Warm Pool at the Last Glacial Maximum, indicating wet or dry hydroclimatic conditions from both marine and terrestrial proxies. terr_raw and marine_raw contain the locations and hydroclimate state at the LGM from a collection of proxy records. Their "val" field indicates whether the proxy captured dry(val=-1)/unchanged(val=0)/wetter(val=1) or fresh(val=-1)/unchanged(val=0)/salty(val=1) climate at the LGM. "n_obs" is the number of proxy techniques used to estimate LGM hydroclimate from each location. is_robust=1 indicates when different proxy techniques agree in their estimates of LGM hydroclimate at each location. is_robust also takes the value of 1 when only one proxy technique is used. "chrono_flag=1" indicates whether the proxy record contains one or more radiocarbon U/Th or well-constrained OSL dates near to or during the LGM. chrono_flag=0 indicates that the LGM was dated via wiggle-matching the local benthic d18O to a global stack or another method. terr_gridded and marine_gridded are the final "gridded" data as seen in the main text of DiNezio and Tierney (2013), in which proxies were averaged within a search radius of 150 km. The "is_robust" field of terr_gridded and marine_gridded indicates whether the observations merged into each "gridded" point agree (is_robust=1) or not (is_robust=0). See DiNezio and Tierney (2013) for more details. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : DiNezio, P.N. Investigator : Tierney, J.E. 2013-05-19 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/14428 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013terr-raw.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/LGM_hydroclimate_proxy_data.mat https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013mar-grid.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013terr-grid.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013mar-raw.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013terr-raw.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/LGM_hydroclimate_proxy_data.mat https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013mar-grid.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013terr-grid.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013mar-raw.txt English https://www.ncdc.noaa.gov/paleo/study/14428 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013terr-raw.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/LGM_hydroclimate_proxy_data.mat https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013mar-grid.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013terr-grid.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/dinezio2013/dinezio2013mar-raw.txt Pedro N. DiNezio and Jessica E. Tierney. 2013. The effect of sea level on glacial Indo-Pacific climate. Nature Geoscience, DOI: 10.1038/ngeo1823. Published online 19-May-2013 START YEAR: 21000 cal yr BP * END YEAR: 18000 cal yr BP 55 -16 -155 20