cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/q81c-g158
title: NOAA/WDS Paleoclimatology - Harvey Fire Data from Churn Creek Protected Area, west central BC, Canada - IMPD - CACPA001

description: This study examines spatially variable stand structure and fire-climate relationships at a low elevation forest-grassland ecotone in west central British Columbia, Canada. Fire history reconstructions were based on samples from 92 fire-scarred trees and stand demography from 27 plots collected over an area of about 7 km2. We documented historical chronologies of widespread fires and localized grassland fires between AD 1600 and 1900. Relationships between fire events, reconstructed values of the Palmer Drought Severity Index and annual precipitation were examined using superposed epoch and bivariate event analyses. Widespread fires occurred during warm, dry years and were preceded by multiple anomalously dry, warm years. Localized fires that affected only grassland-proximal forests were more frequent than widespread fires. These localized fires showed a lagged, positive relationship with wetter conditions. The landscape pattern of forest structure provided further evidence of complex fire activity with multiple plots shown to have experienced low, mixed and/or high-severity fires over the last four centuries. We concluded that this forest-grassland ecotone was characterized by fires of mixed-severity, dominated by frequent, low-severity fires punctuated by widespread fires of moderate to high severity. This landscape-level variability in fire-climate relationships and patterns in forest structure has important implications for fire and grassland management in west central British Columbia and similar environments elsewhere. Forest restoration techniques such as prescribed fire and thinning are oftentimes applied at the forest-grassland ecotone on the basis that historically high frequency, low severity fires defined the character of past fire activity. This study provides forest managers and policy makers important information on mixed severity fire activity at a low elevation forest-grassland ecotone, a crucial prerequisite for the effective management of these complex ecosystems.
description: This site was sampled to reconstruct historical fire regimes in the Churn Creek Protect Area (CCPA).

Ring-boundary fire scars were assigned to the preceding calendar year.

Several metadata files are provided with the FHX file.   -999 in any file indicates no data.
DOI: 10.25921/qafn-p687
title: NOAA/WDS Paleoclimatology - Finlayson, New Zealand Ancient Kauri Radiocarbon and Ringwidth Data

description: Robustly testing hypotheses of geographic synchroneity of abrupt and extreme change during the late Pleistocene (60,000 to 11,650 years ago) requires a level of chronological precision often lacking in ice, marine and terrestrial sequences. Here we report a bidecadally-resolved New Zealand kauri (Agathis australis) tree-ring sequence spanning two millennia that preserves a record of atmospheric radiocarbon (14C) during ice-rafted debris event Heinrich Event 3 (HE3) in the North Atlantic and Antarctic Isotope Maximum 4 (AIM4) in the Southern Hemisphere. Using 14C in the marine Cariaco Basin and 10Be preserved in Greenland ice, the kauri 14C sequence allows us to precisely align sequences across this period. We observe no significant difference between atmospheric and marine 14C records during HE3, suggesting no stratification of surface waters and collapse in Atlantic Meridional Overturning Circulation (AMOC). Instead our results support recent evidence for a weakened AMOC across at least two millennia of the glacial period. Our work adds to a growing body of literature confirming that Heinrich events are not the cause of stadial cooling and suggests changes in the AMOC were not the primary driver of antiphase temperature trends between the hemispheres. Decadally-resolved 14C in ancient kauri offers a powerful new (and complementary) approach to polar ice core CH4 alignment for testing hypotheses of abrupt and extreme climate change.
description: Bidecadal 14C measurements on a 2000 year ancient Kauri tree-ring record from Finlayson, New Zealand.  Floating Finlayson08 ringwidth data series added 10/10/2018.
DOI: 10.25921/qdet-1z43
title: NOAA/WDS Paleoclimatology - Abaco Island Cave, Bahamas 13-32 KYrBP Speleothem Stable Isotope Data

description: Temperature reconstructions across Heinrich stadials 1-3 are presented from an absolute-dated speleothem from Abaco Island in the Bahamas to understand the nature of climate change across these intervals in the subtropical Atlantic. The stalagmite carbonate record, dated by the U-Th geochronometry technique, includes higher d18O and d13C values within Heinrich stadials 1, 2, and 3 followed by rapid declines at the end of the stadials. To aid in the interpretation of these results, the d18O of fluid inclusions associated with the Heinrich stadials were also analyzed. These measurements, which allowed for the relative influence of temperature and d18O of precipitation to be distinguished, demonstrate minimal changes in the d18O of fluid inclusions, suggesting that changes in the d18O values of the speleothem carbonate associated with Heinrich stadials 1-3 are principally driven by an average ~4C temperature decrease, rather than a change in the d18O of the rainfall (hence rainfall amount). These findings support previous work in the North Atlantic and are consistent with the climate response to a weakening of the Atlantic meridional overturning circulation.
description: Stable isotope (d18O, d13C) data from a stalagmite collected in a submerged cave in the Bahamas.  Data extend over the last three Heinrich stadials (~13-32 KYrBP).
DOI: 10.25921/qzy8-5298
title: NOAA/WDS Paleoclimatology - Smith - Mount Hayes - TSME - ITRDB CANA478

description: Tree ring data from the International Tree Ring Data Bank and World Data Center for Paleoclimatology archives.  Most data sets include raw treering measurements (most are annual ring width, with some collections of earlywood or latewood width or wood density), plus chronologies (standardized growth indices for a site compiled from multiple treering samples). Reconstructions of climate variables are included with some of these data sets.  Each data type is stored in a separate data file; the data type is coded into the file name. For details please see: http://www.ncdc.noaa.gov/paleo/treeinfo.htmll
description: NOAA Template Raw Measurements file added 2019-01-27. NOAA Template Raw Measurements file added 2019-02-04. July 2024: Elevation added by WDS-Paleo using get_elev_point() from the elevatr R package with the AWS Terrain Tiles (aws) and WGS 84 reference frame.
DOI: 10.25921/qdws-c192
title: NOAA/WDS Paleoclimatology - Yao fire data from Mengkeshan, Daxing'an Mountain, Heilongjiang, China - IMPD CNMKS001

description: Identification of effects that climate teleconnections, such as El Niño–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and North Atlantic Oscillation (NAO), have on wildfires is difficult because of short and incomplete records in many areas of the world. We developed the first multicentury wildfire chronologies for northeast China from fire-scarred trees. Regional wildfires occurred every 7years from the 1700s to 1947, after which fire suppression policies were implemented. Regional wildfires occurred predominately during drought years and were associated with positive phases of ENSO and PDO and negative NAO. Twentieth century meteorological records show that this contingent combination of +ENSO/+PDO/-NAO is linked to low humidity, low precipitation, and high temperature during or before late spring fire seasons. Climate and wildfires in northeast China may be predictable based on teleconnection phases, although future wildfires may be more severe due to effects of climate change and the legacy of fire suppression.
DOI: 10.25921/qenz-rg49
title: NOAA/WDS Paleoclimatology - Santa Barbara Basin Bulk and Compound Specific Nitrogen Isotope Data

description: The nitrogen (N) isotopic composition (d15N) of bulk sedimentary N (d15Nbulk) is a common tool for studying past biogeochemical cycling in the paleoceanographic record. Empirical evidence suggests that natural fluctuations in the d15N of surface nutrient N are reflected in the d15N of exported planktonic biomass and in sedimentary d15Nbulk. However, d15Nbulk is an analysis of total combustible sedimentary N, and therefore also includes mixtures of N sources and/or selective removal or preservation of N-containing compounds. Compound-specific nitrogen isotope analyses of individual amino acids (d15NAA) are novel measurements with the potential to decouple d15N changes in nutrient N from trophic effects, two main processes that can influence d15Nbulk records.  As a proof of concept study to examine how d15NAA can be applied in marine sedimentary systems, we compare the d15NAA signatures of surface and sinking POM sources with shallow surface sediments from the Santa Barbara Basin, a sub-oxic depositional environmental that exhibits excellent preservation of sedimentary organic matter. Our results demonstrate that d15NAA signatures of both planktonic biomass and sinking POM are well preserved in such surface sediments. However, we also observed an unexpected inverse correlation between d15N value of phenylalanine (d15NPhe; the best AA proxy for N isotopic value at the base of the food web) and calculated trophic position.  We used a simple N isotope mass balance model to confirm that over long time scales, d15NPhe values should in fact be directly dependent on shifts in ecosystem trophic position.  While this result may appear incongruent with current applications of d15NAA in food webs, it is consistent with expectations that paleoarchives will integrate N dynamics over much longer timescales. We therefore propose that for paleoceanographic applications, key d15NAA parameters are ecosystem trophic position, which determines relative partitioning of 15N into source AA versus trophic AA pools, and the integrated d15NAA of all common protein AA (d15NTHAA), which serves as a proxy for the d15N of nutrient N.  Together, we suggest that these can provide a coupled picture of regime shifts in planktonic ecosystem structure, d15N at the base of food webs, and possibly additional information about nutrient dynamics.
description: Bulk and compound specific nitrogen isotopes in shallow surface sediments from Santa Barbara Basin
     Provided Keywords: Santa Barbara Basin, Nitrogen Isotopes, amino acids
DOI: 10.25921/qrh9-5y52
title: NOAA/WDS Paleoclimatology - Veblen fire data from El Valle Rayado - IMPD ARRAY001

description: Records of past fire occurrence from tree rings, charcoal found in lake sediments, and other proxies. Parameter keywords describe what was measured in this data set.  Additional summary information can be found in the abstracts of papers listed in the data set citations.  Additional information on the International Multiproxy Database (IMPD) data set procedures are also available.
DOI: 10.15468/dl.mgjj73
title: Occurrence Download

description: A dataset containing 999 species occurrences available in GBIF matching the query:
{
 "and" : [
 "TaxonKey is one of (Stewartia malacodendron)",
 "StateProvince is one of (Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Texas, Virginia)",
 "BasisOfRecord is Specimen"
 ]
}

 The dataset includes 999 records from 87 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0021260-251009101135966/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.
DOI: 10.25921/q3yf-e744
title: NOAA/WDS Paleoclimatology - Northern Galápagos Coral Sr/Ca Data and SST Reconstruction from 1940-2010 CE

description: Models and observations disagree regarding sea surface temperature (SST) trends in the eastern tropical Pacific (ETP). We present a new Sr/Ca-SST record that spans 1940-2010 from two Wolf Island corals (northern Galápagos). Trend analysis of the Wolf record shows significant warming on multiple timescales, which is also present in several other records and gridded instrumental products. Together, these datasets suggest that most of the ETP has warmed over the 20th century. In contrast, recent decades have been characterized by warming during boreal spring and summer (especially north of the equator), and subtropical cooling during boreal fall and winter (especially south of the equator). These SST trends are consistent with the effects of radiative forcing, mitigated by cooling due to wind forcing during boreal winter, as well as intensified upwelling and a strengthened Equatorial Undercurrent.
description: Provided Keywords: corals, eastern tropical Pacific, ocean dynamical thermostat, sea surface temperature, climate change
DOI: 10.25921/q1a8-5n83
title: NOAA/WDS Paleoclimatology - Taylor Dome Ice Core 31,000 Year Mineral Dust Radiogenic Isotope and Elemental Data

description: Recent declines in ice shelf and sea ice extent experienced in polar regions highlight the importance of evaluating variations in local weather patterns in response to climate change. Airborne mineral particles (dust) transported through the atmosphere and deposited on ice sheets and glaciers in Antarctica and Greenland can provide a robust set of tools for resolving the evolution of climatic systems through time. Here we present the first high time resolution radiogenic isotope (strontium and neodymium) data for Holocene dust in a coastal East Antarctic ice core, accompanied by rare earth element composition, dust concentration, and particle size distribution during the last deglaciation. We aim to use these combined ice core data to determine dust provenance, with variations indicative of shifts in either dust production, sources, and/or transport pathways. We analyzed a series of 17 samples from the Taylor Dome (77 47'47"S, 158 43'26"E) ice core, 113-391 m in depth from 1.1-31.4 ka. Radiogenic isotopic and rare earth element compositions of dust during the last glacial period are in good agreement with previously measured East Antarctic ice core dust records. In contrast, the Holocene dust dataset displays a broad range in isotopic and rare earth element compositions, suggesting a shift from long-range transported dust to a more variable, local input that may be linked to the retreat of the Ross Ice Shelf during the last deglaciation. Observed changes in the dust cycle inferred from a coastal East Antarctic ice core can thus be used to infer an evolving local climate.
description: Mineral dust concentration, radiogenic isotopes, and rare earth element data from the Taylor Dome ice core, Antarctica, for the past 31,000 years.  Data were measured with both Traditional Acid Leach and Full Acid Digestion methods. Provided Keywords: Antarctica, dust, ice core, strontium, neodymium, rare earth elements
DOI: 10.25921/q647-b191
title: NOAA/WDS Paleoclimatology - Little Cayman, Cayman Islands, Coral d18O and Sr/Ca Data from 1887-2011 CE

description: Atlantic Warm Pool (AWP) climate variability is subject tomultiple influences of remote and local forcing. However, shortage of observational data before the midtwentieth century and of long-term sea surface temperature (SST) and climate records has hampered the detection and investigation of decadal- and longer-scale variability. We present new seasonally resolved 125-year records of coral d18O and Sr/Ca variations in the Central Caribbean Sea (Little Cayman, Cayman Islands; Diploria strigosa). Both geochemical proxies show decreasing long-term trends, indicating long-term warming. Sr/Ca indicates much stronger regional warming than large-scale grid-SST data, while d18O tracks large-scale SST changes in the Atlantic Warm Pool. Seawater d18O variations are reconstructed, indicating a drying trend over the past century. High spatial correlation between coral d18O and SST in the region of the Loop Current and Gulf Stream system suggests that Little Cayman is a sensitive location for detecting past large-scale temperature variability beyond the Central Caribbean region. More specifically, our d18O data track changes in North Atlantic Oscillation variability on decadal and multidecadal time scales providing insights into the temporal and spatial nonstationarity of the North Atlantic Oscillation. A combination of our d18O record with two coral records from different Caribbean sites reveals high spatial correspondence between coral d18O and SST variability in the North Atlantic subtropical gyre, where few instrumental measurements and proxies are available prior to the twentieth century. Our results clearly demonstrate the potential of combining proxy data to provide information from sparsely sampled areas, helping to reduce uncertainty in model-based projections.
description: Chronologies based on seasonal cycles in trace element ratios; Analytical uncertainty: d18O D. strigosa  = 0.06 per mil; Sr/Ca D. strigosa = 0.01 mmol/mol
       Provided Keywords: corals, Sr/Ca, oxygen isotopes, Cayman Islands, Caribbean
DOI: 10.25921/qqke-s157
title: NOAA/WDS Paleoclimatology - West Turkana, Kenya 1.9-1.4 Ma Leaf Wax Hydrogen and Carbon Isotope Data

description: Climate is thought to play a critical role in human evolution; however, this hypothesis is difficult to test due to a lack of long, high-quality paleoclimate records from key hominin fossil locales. To address this issue, we analyzed organic geochemical indicators of climate in a drill core from West Turkana, Kenya that spans ~1.9-1.4 Ma, an interval that includes several important hominin evolutionary transitions. We analyzed the hydrogen isotopic composition of terrestrial plant waxes (dDwax) to reconstruct orbital-timescale changes in regional hydrology and their relationship with global climate forcings and the hominin fossil record. Our data indicate little change in the long-term mean hydroclimate during this interval, in contrast to inferred changes in the level of Lake Turkana, suggesting that lake level may be responding dominantly to deltaic progradation or tectonically-driven changes in basin configuration as opposed to hydroclimate. Time-series spectral analyses of the isotopic data reveal strong precession-band (21 kyr) periodicity, indicating that regional hydroclimate was strongly affected by changes in insolation. We observe an interval of particularly high-amplitude hydrologic variation at ~1.7 Ma, which occurs during a time of high orbital eccentricity hence large changes in processionally-driven insolation amplitude. This interval overlaps with multiple hominin species turnovers, the appearance of new stone tool technology, and hominin dispersal out of Africa, supporting the notion that climate variability played an important role in hominin evolution.
description: Hydrogen and carbon isotopes of higher plant leaf waxes (dDwax and d13Cwax) from West Turkana, Kenya, covering ~1.9-1.4 Ma.
DOI: 10.25921/qtac-2s37
title: NOAA/WDS Paleoclimatology - Lavergne - Challhuaco - NOPU - ITRDB ARGE140

description: Over the last decades, gradual changes in summer climate in the Southern Hemisphere have affected forest growth in contrasting ways in moist and dry regions. Here, we use correlation analysis and a forward process-based model (Vaganov-Shashkin-Lite) to investigate changes in climate limitation of the interannual tree-ring growth of Nothofagus pumilio at the upper treeline along a precipitation gradient in northern Patagonia. Patterns of climate limitation vary consistently along the gradient. At mesic and humid treelines, tree-ring growth is positively related to growing season temperature and negatively to precipitation. At xeric treelines, the opposite is observed. Moreover, the climate-growth relations are not stationary. In particular, according to the model, the step decrease in precipitation in 1952 induced an increase of the moisture limitation at the dry edge of the gradient. Correlation analyses evidence that the dependence of growth on moisture after 1952 has enhanced since 1976. While the model consistently reproduces tree-ring width variations over the 1931-1975 period, it does not capture the growth patterns in the following years. Some environmental parameters (cloudiness, snowpack, atmospheric CO2) affecting moisture, radiation and stomatal aperture may have reached thresholds beyond which the effect on tree-growth has become sizable.
description: NOAA Template Raw Measurements file added 2019-04-29.
DOI: 10.25921/qpgz-ce17
title: NOAA/WDS Paleoclimatology - Big Lake, Western Canada Past Six Millennia Sediment Data

description: Inferences of past climatic conditions from a sedimentary record from Big Lake, British Columbia, Canada, over the past 5,500 years show strong millennial-scale patterns, which oscillate between periods of wet and drier climatic conditions. Higher frequency decadal- to centennial-scale fluctuations also occur within the dominant millennial-scale patterns. These changes in climatic conditions are based on estimates of changes in lake depth and salinity inferred from diatom assemblages in a well dated sediment core. After periods of relative stability, abrupt shifts in diatom assemblages and inferred climatic conditions occur approximately every 1,220 years. The correspondence of these shifts to millennial-scale variations in records of glacial expansion/recession and ice-rafting events in the Atlantic suggest that abrupt millennial-scale shifts are important to understanding climatic variability in North America during the mid- to late Holocene. Unfortunately, the spatial patterns and mechanisms behind these large and abrupt swings are poorly understood. Similar abrupt and prolonged changes in climatic conditions today could pose major societal challenges for many regions.
description: Lake depth reconstruction based on diatom assemblage, for the past 5,500 years
DOI: 10.25921/q4vt-nz54
title: NOAA/WDS Paleoclimatology - North Pacific Temperature and Productivity Reconstructions and Diatom Species Data

description: Records of past climate and ocean circulation derived from marine sediments. Parameter keywords describe what was measured in this data set.  Additional summary information can be found in the abstracts of papers listed in the data set citations.
description: Estimation of Primary Production and Sea Surface Temperature using Diatom based Transfer Functions
 Provided Keywords: Diatoms, Primary Productivity, Sea surface Temperature Transfer functions