This README-Goldsmithetal-ClimaticInfluencesonSOI-28Feb22.txt was generated on 28 February 2022 by G.R. Goldsmith. Refer to associated EML file for full metadata. GENERAL INFORMATION 1. Title of Dataset: Data from: Climatic influences on summer use of winter precipitation by trees 2. Authors: Gregory R. Goldsmith, Scott T. Allen, Sabine Braun3, Rolf T.W. Siegwolf4, & James W. Kirchner4,5 a) Schmid College of Science and Technology, Chapman University, Orange CA 92866, USA b) Department of Natural Resources and Environmental Science, University of Nevada, Reno, Reno, NV 89557, USA c) Institute for Applied Plant Biology, 4124 Witterswil, Switzerland d) Swiss Federal Research Institute for Forest, Snow and Landscape, WSL, 8903 Birmensdorf, Switzerland e) Department of Environmental Systems Science, ETH Zurich, 8092 Zurich, Switzerland 3. Corresponding author: Gregory R. Goldsmith (goldsmith@chapman.edu; +1-714-516-5881) 4. Date of data collection: 2015-2019 5. Geographic location of data collection: Switzerland 6. Species: beech (Fagus sylvatica L.), spruce (Picea abies (L.) H. Karst.), and oak (Quercus robur L.) 7. Funding sources that supported the collection of the data: Swiss Federal Office of the Environment 8. Citation: Goldsmith, G.R. et al. (2022) Data from:Climatic influences on summer use of winter precipitation by trees. Dryad, Dataset. DATA & FILE OVERVIEW 1. Description of dataset: Files included provide all of the data necessary to reproduce the analysis of the manuscript entitled "Climatic influences on summer use of winter precipitation by trees", which can be accessed at: https://www.essoar.org/doi/abs/10.1002/essoar.10510659.1 and is in review as of 28 February 2022. This includes sampling site names and locations, stable isotopes of water in tree xylem sampled at each site, the calculation of the seasonal origin index of source water at each site, and weather and climate observed at each site. 2. File List File 1: Goldsmithetal-ClimaticInfluencesonSOI-MetaData-10Feb22.csv File 1 Description: Metadata necessary for interpreting column headers in File 2, which is entitled: Goldsmithetal-ClimaticInfluencesonSOI-Data-10Feb22.csv File 2: Goldsmithetal-ClimaticInfluencesonSOI-Data-10Feb22.csv File 2 Description: Site Characteristics, stable isotopes of water in tree xylem, seasonal origin index calculations, weather and site File 3: Goldsmithetal-ClimaticInfluencesonSOI-EML-10Feb22.xml File 3 Description: Metadata provided in ecological markup language. Redundant to the present README file, but required by Dryad. METHODOLOGY Field sampling: Our study is carried out in the context of a long-term forest health monitoring program that now includes nearly 200 sites (Braun et al., 2017, 2020). Each site contains at least one of three key tree species: beech (Fagus sylvatica L.), spruce (Picea abies (L.) H. Karst.), and oak (Quercus robur L.). We collected samples from 8 individuals of each species between 22 July and 3 August 2019 from 24 sites (n = 258 trees in total, one site has 10 individuals of a species). Fully sunlit branches were collected using pole pruners by a technician suspended below a helicopter. Samples were returned to the ground, immediately enclosed in a black plastic trash bag to suppress transpiration, and left in a refrigerated cooler until further processing (< 24 h). Sites were selected to be broadly representative of the ranges of temperature, precipitation, elevation, and longitude included in the monitoring network as a whole. We compare our observations in 2019 to observations in the same 24 sites from our original sampling in 2015, where we collected samples using the same methodology from 3-8 of the same individuals of each species (n = 147 trees in total); this sampling was conducted between 27 July and 10 August 2015. A smaller subset of these sites was sampled in 2018 (n = 42 trees in total), which is discussed in the supporting information. Sample processing: For each sample, the bark and vascular cambium were removed from a fully suberized piece of the branch, the remaining xylem sealed in a glass vial, and the vial frozen until water extraction. Water extraction was carried out via cryogenic vacuum distillation at the Paul Scherrer Institute (2015) and at ETH Zurich (2019) on manifolds with an identical design as described in (Orlowski et al., 2013). Branch samples were extracted under a 0.03 hPa vacuum for 2 h at 80 ¼C and the evaporated water frozen in a liquid nitrogen trap. Samples were then analyzed for delta18O and delta2H by TC/EA-IRMS in the Siegwolf Lab at the Paul Scherrer Institute (2015) and in the Kirchner Lab at ETH Zurich (2019). All values are presented per mil (ä) relative to V-SMOW. The standard deviation of an independent quality control standard used for analysis at the Paul Scherrer Institute was ² 0.2 ä delta18O and ² 0.4 ä delta2H. The standard deviation of an independent quality control standard used for analysis at ETH Zurich was 0.17 ä delta18O and 0.62 ä delta2H. Analytical approach: To determine the seasonal origin of the precipitation in trees, we used an index of the isotopic signature of plant xylem water relative to seasonal cycles of isotopes in precipitation (Allen et al., 2019b). This seasonal origin index (SOI) can be estimated by determining the fractionation-compensated delta2H isotopic signature of xylem water, and the delta2H isotopic signatures of winter, summer, and volume-weighted annual precipitation at each study site. The compensation for fractionation introduced by evaporation involves projecting dual-isotope measurements of xylem water to local meteoric water lines along theoretical evaporation-line slopes, using the method described in detail in Allen et al. (2019b). Isotopic signatures of precipitation were estimated using data from the two years prior to sampling and a previously described and validated model (Allen et al., 2018). SOI provides a measure of the overrepresentation of a seasonÕs precipitation in xylem relative to the representation of that seasonÕs precipitation in the annual precipitation amount. Negative values of SOI suggest an overrepresentation of winter precipitation in xylem and positive values suggest an overrepresentation of summer precipitation in xylem. The SOI will be near -1.0 for soil and plant water samples derived entirely from winter precipitation and near 1.0 for samples derived entirely from summer precipitation. Literature Cited Allen ST, Freyberg J von, Weiler M, Goldsmith GR, Kirchner JW. 2019a. The Seasonal Origins of Streamwater in Switzerland. Geophysical Research Letters 46: 10425Ð10434. Allen ST, Kirchner JW, Braun S, Siegwolf RTW, Goldsmith GR. 2019b. Seasonal origins of soil water used by trees. Hydrology and Earth System Sciences 23: 1199Ð1210. Allen ST, Kirchner JW, Goldsmith GR. 2018. Predicting Spatial Patterns in Precipitation Isotope (delta 2-H and delta 18-O) Seasonality Using Sinusoidal Isoscapes. Geophysical Research Letters 45: 4859Ð4868. Braun S, Schindler C, Rihm B. 2017. Growth trends of beech and Norway spruce in Switzerland: The role of nitrogen deposition, ozone, mineral nutrition and climate. Science of The Total Environment 599Ð600: 637Ð646. Braun S, Schindler C, Rihm B. 2020. Foliar Nutrient Concentrations of European Beech in Switzerland: Relations With Nitrogen Deposition, Ozone, Climate and Soil Chemistry. Frontiers in Forests and Global Change 3. Orlowski N, Frede H-G, BrŸggemann N, Breuer L. 2013. Validation and application of a cryogenic vacuum extraction system for soil and plant water extraction for isotope analysis. Journal of Sensors and Sensor Systems 2: 179Ð193. DATA-SPECIFIC INFORMATION FOR: Goldsmithetal-ClimaticInfluencesonSOI-Data-10Feb22.csv 1. Number of variables: 39 2. Number of cases/rows: 447 3. Comma-Delimited Variable List (attributeName,attributeDefinition,formatString,definition,unit,numberType): Year,Year in which data were collected,"YYYY",,, siteID,Site # assigned by Institute for Applied Plant Biology (co-author Braun) ,,,, Location,Site name assigned by Institute for Applied Plant Biology (co-author Braun),,,, Species,Common name of tree species: beech (Fagus sylvatica L.), spruce (Picea abies (L.) H. Karst.), and oak (Quercus robur L.). ,,,, Color,Sample trees are assigned a permanent colored band to facilitate repeat sampling by Institute for Applied Plant Biology (co-author Braun).,,,, Delta_2H_xylem,Hydrogen (2/1) isotope ratio of xylem water,,,per mille relative to V-SMOW,real Delta_18O_xylem,Oxygen (18/16) isotope ratio of xylem water,,,per mille relative to V-SMOW,real Latitude,Site latitude,,,Decimal degrees,real Longitude,Site longitude,,,Decimal degrees,real Elev,Site elevation (above sea level),,,meter,real AnnP,Long-term site mean annual precipitation ,,,millimeter,real PrecipOlong-term mean,Long-term site mean oxygen isotope ratios in precipitation ,,,per mille relative to V-SMOW,real PrecipDprev2yr,Site mean hydrogen isotope ratios in precipitation of previous two years,,,per mille relative to V-SMOW,real 2HAmp,Modeled amplitude of the site annual cycle of hydrogen isotopes in precipitation,,,per mille relative to V-SMOW,real 2H phase,Modeled phase of the site annual cycle of hydrogen isotopes in precipitation,,,per mille relative to V-SMOW,real 2H offset,Modeled offset of the site annual cycle of hydrogen isotopes in precipitation,,,per mille relative to V-SMOW,real 18OAmp,Modeled amplitude of the site annual cycle of oxygen isotopes in precipitation,,,per mille relative to V-SMOW,real 18O phase,Modeled phase of the site annual cycle of oxygen isotopes in precipitation,,,per mille relative to V-SMOW,real 18O offset,Modeled offset of the site annual cycle of oxgen isotopes in precipitation,,,per mille relative to V-SMOW,real EvapLineSlope,Slope of the evaporation line projecting xylem water to site local meteoric water line (LMWL),,,,real LMWLint,Intercept of site local meteoric water line (LMWL),,,per mille relative to V-SMOW,real LMWLslope,Slope of local meteoric water line (LMWL),,,,real evap line y intercept,Hydrogen isotope ratio of the intercept of evaporation line projecting xylem water to site local meteoric water line (LMWL),,,per mille relative to V-SMOW,real evapline-lmwl intercept, 18O,Oxygen isotope ratio of the intersection of the evaporation line with the local meteoric water line (LMWL),,,per mille relative to V-SMOW,real source-evapline-lmwl intercept, 2H,Hydrogen isotope ratio of the intersection of the evaporation line with the local meteoric water line (LMWL),,,per mille relative to V-SMOW,real SOI prev2yearP,Seasonal origin index of water in tree xylem, based on precipitation isotopes of previous two years (unitless),,,,real 6.1permilbiascorrectedSource,Hydrogen isotope ratio of xylem water assuming a bias of -6.1 per mille,,,per mille relative to V-SMOW,real 6.1permilbiascorrectedSOI,Seasonal origin index of water in tree xylem, based on precipitation isotopes of previous two years, with bias correction (unitless),,,,real T_Julymean(yearof),Mean site temperature for month of July in year of sampling,,,celsius,real T_JuneJuly(yearof),Mean site temperature for months of June/July in year of sampling,,,celsius,real VPD_Julymean(yearof),Mean site vapor pressure deficit for month of July in year of sampling,,,kPa,real VPD_JuneJuly(yearof),Mean site vapor pressure deficit for months of June/July in year of sampling,,,kPa,real PET_Julymean(yearof),Mean site potential evapotranspiration for month of July in year of sampling ,,,millimeter,real PET_JuneJuly(yearof),Mean site potential evapotranspiration for month of June/July in year of sampling ,,,millimeter,real Pjuly(Yearof),Total site precipitation for month of July in year of sampling ,,,millimeter,real PJuneJuly(Yearof),Total site precipitation for month of June/July in year of sampling ,,,millimeter,real Pann(July-AugY-1),Total site precipitation of the year prior to sampling (August through July) ,,,millimeter,real Julyover5,Total site precipitation for month of July in year of sampling, only events over 5 mm,,,millimeter,real junejulyover5,Total site precipitation for month of June/July in year of sampling, only events over 5 mm,,,millimeter,real 4. Missing data codes: Cell is left blank