noaa-recon-20062 US West Coast 500 Year Gridded Standardized Precipitation Index Reconstruction Wise, E.K. US West Coast 500 Year Gridded Standardized Precipitation Index Reconstruction 2016-04-22 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/20062 Investigator E.K. Wise 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 standardized precipitation index,null,correlation coefficient,dimensionless,Oct-Mar,climate reconstructions|tree ring,null,null,N,Pearson correlation coefficient (R) between the predicted and observed data earth science paleoclimate climate reconstructions|tree ring standardized precipitation index,null,verification coefficient of efficiency,dimensionless,Oct-Mar,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring standardized precipitation index,null,bias,dimensionless,Oct-Mar,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring standardized precipitation index,null,null,dimensionless,Oct-Mar,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring standardized precipitation index,null,verification root mean square error,dimensionless,Oct-Mar,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring standardized precipitation index,null,null,null,null,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring latitude,null,null,degree north,null,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring longitude,null,null,degree east,null,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring p-value,null,null,dimensionless,Oct-Mar,climate reconstructions|tree ring,null,null,N,p-values associated with correlation coefficients earth science paleoclimate climate reconstructions|tree ring standardized precipitation index,null,null,dimensionless,Oct-Mar,climate reconstructions|tree ring,null,null,N,standard deviation ratio (SDR) earth science paleoclimate reconstructions precipitation geoscientificInformation Precipitation Reconstruction 1500 AD 2013 AD 450 cal yr BP -63 cal yr BP Complete 32 49 -125 -114 Continent North America United States Of America US West Coast>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 Erika K. Wise 2016 Geophysical Research Letters 43 10.1002/2016GL068487 http://onlinelibrary.wiley.com/doi/10.1002/2016GL068487/full

The U.S. West Coast drought commencing in 2012 developed in association with a large, persistent high-pressure ridge linked to internal atmospheric variability. This study places the occurrence, spatial patterns, and associated circulation features of West Coast drought into a paleoclimate context through a synoptic dendroclimatology approach linking atmospheric circulation to surface hydroclimate patterns. Spatial reconstructions of upper-atmosphere pressure patterns and cool-season drought show that West Coast-wide drought, although relatively rare compared to north-south dipole drought, has occurred periodically since 1500 CE and is consistently associated with a strong ridge centered along the Pacific Northwest coast. Atmospheric blocking is also linked to north-dry dipole droughts, while south-dry and wider Western droughts indicate La Niña-type patterns. The transition latitude between the northern and southern sides of the western precipitation dipole, important for California hydroclimate patterns, has had frequent year-to-year fluctuations but remained centered on 40°N over the past five centuries. STUDY NOTES: Tree-ring based, gridded (0.5°x0.5°) cool-season (Oct-Mar) Standardized Precipitation Index (SPI) reconstruction for the US West Coast 1500-2013 CE.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/northamerica/usa/wise2016spi-readme.txt Data Description; Standardized Precipitation Index Reconstruction Readme File GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/northamerica/usa/wise2016spi.nc netCDF Data File; Standardized Precipitation Index Reconstruction GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/northamerica/usa/wise2016spi.txt Text Array Data File; Standardized Precipitation Index Reconstruction USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11