Global 2,000 Year Paleo Hydrodynamics Data Assimilation product (PHYDA) Steiger, N.J.; Smerdon, J.E.; Cook, E.R.; Cook, B.I. Steiger, N.J. Smerdon, J.E. Cook, E.R. Cook, B.I. Air Temperature Reconstruction Atmospheric and Oceanic Circulation Patterns Reconstruction Palmer Drought Index Reconstruction earth science/paleoclimate/reconstructions earth science/paleoclimate/reconstructions (Global>LATITUDE >LONGITUDE ) Hydroclimate extremes critically affect human and natural systems, but there remain many unanswered questions about their causes and how to interpret their dynamics in the past and in climate change projections. These uncertainties are due, in part, to the lack of long-term, spatially resolved hydroclimate reconstructions and information on the underlying physical drivers for many regions. Here we present the first global reconstructions of hydroclimate and associated climate dynamical variables over the past two thousand years. We use a data assimilation approach tailored to reconstruct hydroclimate that optimally combines 2,978 paleoclimate proxy-data time series with the physical constraints of an atmosphere-ocean climate model. The global reconstructions are annually or seasonally resolved and include two spatiotemporal drought indices, near-surface air temperature, an index of North Atlantic variability, the location of the intertropical convergence zone, and monthly Nino indices. This database, called the Paleo Hydrodynamics Data Assimilation product (PHYDA), will provide a critical new platform for investigating the causes of past climate variability and extremes, while informing interpretations of future hydroclimate projections. STUDY NOTES: Paleohydrodynamic proxy data set and global hydroclimate reconstructions for the past 2,000 years. Included are reconstructions of three global variables gridded at ~2 degree resolution: surface temperature at 2m, the Palmer drought severity index (PDSI), and the standardized precipitation evapotranspiration index (SPEI). Also reconstructed are climate indices at annual, JJA, and DJF temporal resolutions: the global mean temperature, the North Atlantic sea surface temperature index (which is the non-detrended and non-smoothed version of the Atlantic multidecadal oscillation index (AMO), and the location of the intertropical convergence zone (ITCZ) in 11 longitudinal zones. Also reconstructed are the monthly Nino sea surface temperature (SST) indices (Nino 1+2, 3, 3.4, 4) and the monthly equatorial Pacific zonal SST gradient. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Steiger, N.J. Investigator : Smerdon, J.E. Investigator : Cook, E.R. Investigator : Cook, B.I. 2018-05-25 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/24230 https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/steiger2018/readme-steiger2018.txt https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/steiger2018/ https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/steiger2018/readme-steiger2018.txt https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/steiger2018/ English https://www.ncdc.noaa.gov/paleo/study/24230 https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/steiger2018/readme-steiger2018.txt https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/steiger2018/ Nathan J. Steiger, Jason E. Smerdon, Edward R. Cook, Benjamin I. Cook2018A reconstruction of global hydroclimate and dynamical variables over the Common EraScientific Data180086510.1038/sdata.2018.86https://www.nature.com/articles/sdata201886 START YEAR: 0 AD * END YEAR: 2000 AD -180 -90 180 90