cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/vnty-3891
title: NOAA/WDS Paleoclimatology - Iniguez fire data from Catalina Butterfly Peak Plot 33 - IMPD USCBP_33

description: Fire histories contribute important information to contemporary fire planning, however, our knowledge is not comprehensive geographically. We evaluated the influence of topography on fire history patterns in two contrasting landscapes within the Santa Catalina Mountains of southeastern Arizona. Multiple fire-scarred trees from randomly selected 2-ha plots were used to develop plot composite mean fire intervals (PCMFIs) within the Butterfly Peak (BP) and Rose Canyon (RC) landscapes. BP is dominated by steep, northerly aspects and presence of potential fire spread barriers (exposed rock bluffs and scree slopes). RC is dominated by more gentle and southerly aspects with relatively few fire barriers. Within each landscape, PCMFIs did not differ significantly between aspect classes from A.D. 1748 to 1910 (BP: p = 0.73 and RC: p = 0.57). Pooled PCMFIs in the gentler RC landscape were, however, significantly shorter (p < 0.001) than in the steeper BP landscape. The frequency of relatively widespread fires (i.e., number of fire years when ≥2 plots scarred) was similar between landscapes, but fires in the gentler RC landscape were significantly larger (p = 0.033). The higher frequency of large fires (i.e., fires that burned >75% of the landscape) in RC resulted in more area burned over time and shorter fire intervals at individual plots. Conversely, smaller fires in the dissected BP landscape resulted in less area burned and longer periods between fires at individual plots. The different topographies in the two landscapes likely result in different wind intensities, fuel moistures, and fuel/vegetation types—and consequently, different historical fire spread patterns. Our conclusion is that fire history patterns are not influenced primarily by stand-scale topography, but rather by the topographic characteristics of the broader, surrounding landscape.
description: 
This dataset was contributed as part of the North American Tree-ring Fire Scar Synthesis (NAFSS) project (https://www.ncei.noaa.gov/access/paleo-search/study/34853). Data were contributed to the project from the original data generators.

Sample Storage Location: Laboratory of Tree-Ring, University of Arizona
Dating Method: Dated
Related ITRDB_Chronology: Not Applicable

Fire scar data from this site are available in FHX2 format at:
  https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/uscbp_33.fhx
along with associated metadata at:
  https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/uscbp_33-noaa.txt
DOI: 10.25921/vh7f-w840
title: NOAA/WDS Paleoclimatology - Tree-Ring Based Streamflow Reconstructions for the Pacific Northwest, U.S.A. covering 1280-2006 CE

description: Water resources in the Pacific Northwest (PNW) are characterized by significant interannual to interdecadal variation. Paleo-proxy reconstructions such as those derived from tree-rings provide longer-term context and supplement information on this expected range of variability, which can improve planning, management, and response related to extreme events and hydrologic change. However, existing paleo-proxy reconstructions have yet to address the potential for pronounced within- and among-basin variations in the PNW due to a lack of spatial coverage. Here we develop methodologically consistent reconstructions for 36 gages in the PNW, including the Columbia and Snake River drainages, as well as key coastal watersheds. These reconstructions extend back at least to the 1500s coefficient of efficiency. Reconstruction skill is relatively high (mean R2 = 0.63), and snowpack- or winter precipitation-sensitive chronologies from high-elevation sites provide important contributions to reconstruction skill. At the whole-region scale, reconstructed variability indicates evidence for drier and wetter years, more persistent decadal variability, and correspondingly longer episodes of deficit and surplus compared to instrumental records. Within the region, this expanded range of extremes appears especially prevalent in the Snake River and southern PNW watersheds. Regionally, cumulative deficits in the early 1500s and mid 1600s rival those of the early 20th century, though persistence and timing vary widely among basins. These reconstructions suggest that considering within-region variability will be key for water management and planning under climate change, and that sub-regional adaptation strategies are likely to be advantageous.
description: Network of tree-ring based streamflow constructions at gages in the Pacific Northwest, USA
  Provided Keywords: Dendroclimatology, streamflow, reconstruction, paleoclimate, hydroclimate
DOI: 10.25921/vt6x-e185
title: NOAA/WDS Paleoclimatology - Wiles - Secrest Bald Cypress - TADI - ITRDB OH022

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
DOI: 10.25921/v24r-wp06
title: NOAA/WDS Paleoclimatology - O'Connor fire data from Pinalenos_M20, Southeast Arizona - IMPD USM20001

description: In recent decades fire size and severity have been increasing in high elevation forests of the American Southwest. Ecological outcomes of these increases are difficult to gauge without an historical context for the role of fire in these systems prior to interruption by Euro-American land uses. Across the gradient of forest types in the Pinaleño Mountains, a Sky Island system in southeast Arizona that experienced two relatively large high-severity fires in the last two decades, we compared fire characteristics and climate associations before and after the onset of fire exclusion to determine the degree of similarity between past and recent fires. We use a gridded fire scar and demography sampling network to reconstruct spatially explicit estimates of fire extent and burn severity, as well as climate associations of fires from individual site to landscape scales from 1640 to 2008 C.E. We found that patterns of fire frequency, size, and severity were relatively stable for at least several centuries prior to 1880. A combination of livestock grazing and active fire suppression after circa 1880 led to (1) a significant reduction in fire spread but not fire ignition, (2) a conversion of more than 80% of the landscape from a frequent, low to mixed-severity fire regime to an infrequent mixed to high-severity fire regime, and (3) an increase in fuel continuity within a mid-elevation zone of dry mixed-conifer forest, resulting in increased opportunities for surface and crown fire spread into higher elevation mesic forests. The two most recent fires affecting mesic forests were associated with drought and temperature conditions that were not exceptional in the historical record but that resulted in a relative proportion of high burn severity up to four times that of previous large fires. The ecological effects of these recent fires appear to be more severe than any fire in the reconstructed period, casting uncertainty upon the recovery of historical species composition in high-severity burn patches. Significant changes to the spatial pattern, frequency, and climate associations of spreading fires after 1880 suggest that limits to fuel loading and fuel connectivity sustained by frequent fire have been removed. Coinciding factors of high fuel continuity and fuel loading, projected lengthening of the fire season, and increased variability in seasonal precipitation suggest that large high-severity fires, especially in mixed-conifer forests, will become the predominant fire type without aggressive actions to reduce fuel continuity and restore fire-resilient forest structure and species composition.
description: This dataset was contributed as part of the North American Tree-ring Fire Scar Synthesis (NAFSS) project (https://www.ncei.noaa.gov/access/paleo-search/study/34853). Data were contributed to the project from the original data generators.
DOI: 10.25921/v1pb-vb30
title: NOAA/WDS Paleoclimatology - South Atlantic Coccolith Assemblage and Morphology Data from the Early Oligocene

description: Early Oligocene global climate was characterized by initiated Antarctic glaciation and meridional overturning circulation, which then led to profound eutrophication in the upper ocean. Generating a high-resolution coccolith record help to understand the responses of the marine phytoplankton to the newly established environment. Using highly resolved (~6 kyr time-resolution) marine sediment samples from Deep Sea Drilling Project Site 522 in the South Atlantic Ocean, we conducted a comprehensive morphologic study on coccoliths from the genera Reticulofenestra, Dictyococcites and Coccolithus, that dominated the interval between ~33.1 to 32.8 Ma. Our results showed that the size variations of three measured genera are significantly correlated (p<0.01) to each other, indicating homogeneous responses to the environmental changes. Moreover, spectrum analysis on integrated morphologic data of all measured coccoliths showed distinct obliquity (~40-kyr) and precession (~23-kyr and ~18-kyr) cycles. We suggest that these variations were mainly driven by temperate, short-term ecological fluctuations, which periodically altered the nutrient condition in the common living habitats for the studied coccolithophores. We proposed two tentative explanations focusing on the obliquity signal. First, the cyclic variation could result from obliquity-modulated ice volume changes and variations in ocean circulation intensity, which influenced nutrient export from deep waters to the upper ocean. Alternatively, the changes in coccolith size may indicate the strength of seasonality that influenced the upper ocean mixing on the west coast of South Africa.
description: The dataset includes coccolithophores morphology and assemblage from the South Atlantic Ocean, early Oligocene (~32.8-33.1 Ma). The data are derived from 45 marine sediment samples collected at DSDP Site 522, Core 33. The first dataset is the relative abundances (%) of different species/genera of coccolithophores. The second dataset is the morphology record (size, given in µm) that obtained by measuring 100, 30 and 30 specimens of coccolithophore genra Reticulofenestra, Dictyococcites and Coccolithus, repectively.
DOI: 10.25921/vpmg-jm56
title: NOAA/WDS Paleoclimatology - Qunf Cave, Oman d18O, d13C, d17O Excess, Fluid Inclusion Hydrogen Isotope, and Trace Metal Data Over the Past 11,000 Years

description: Qunf Cave oxygen isotope (d18Oc) record from southern Oman is one of the most significant of few Holocene Indian summer monsoon cave records. However, the interpretation of the Qunf d18Oc remains in dispute. Here we provide multiple proxy records from Qunf Cave and climate model simulations to reconstruct the Holocene local and regional hydroclimate changes. The results indicate that besides the Indian summer monsoon, the North African summer monsoon also contributes water vapor to southern Oman during the early to middle Holocene. In principle, Qunf d18Oc values reflect integrated oxygen-isotope fractionations over a broad moisture transport swath from moisture sources to the cave site, rather than local precipitation amount alone, and thus the Qunf d18Oc record characterizes primary changes in the super-monsoon regime across the Holocene. In contrast, other Qunf Cave proxy records appear to suggest an overall slightly increased or unchanged wetness over the Holocene at the cave site.
DOI: 10.15468/dl.5rzx8n
title: Occurrence Download

description: A dataset containing 5627 species occurrences available in GBIF matching the query:
{
 "and" : [
 "Country is Korea, Republic of",
 "TaxonKey is Pinus densiflora"
 ]
}

 The dataset includes 5627 records from 72 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0024614-251009101135966/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.
DOI: 10.25921/v870-cb85
title: NOAA/WDS Paleoclimatology - Summer Air Temperature Reconstruction in Tierra del Fuego from 1765-2002 CE

description: Proxy climate records, such as those derived from tree rings, are necessary to extend relatively short instrumental meteorological observations into the past. Tierra del Fuego is the most austral territory with forests in the world, situated close to the Antarctic Peninsula, which makes this region especially interesting for paleoclimatic research. However, high-quality, high-resolution summer temperature reconstruction are lacking in the region. In this study we used 63 tree-ring width chronologies of Nothofagus pumilio and Nothofagus betuloides and partial least squares regression (PLSR) to produce annually resolved December-to-February temperature reconstruction. The resulting reconstruction extends back to AD 1765 and explains 37–50% of instrumental temperature variability. We found that observed summer temperature variability in Tierra del Fuego is primarily driven by the fluctuations of atmospheric pressure systems both in the South Atlantic and South Pacific, while it is insignificantly correlated to major hemispheric modes: El Niño–Southern Oscillation and Southern Annular Mode. This fact makes our reconstruction important for climate modelling experiments, as it represents specific regional variability. Our reconstruction can be used for direct comparison with model outputs to better understand model limitations or to tune a model. The reconstruction can contribute to larger scale reconstructions based on paleoclimatic data assimilation. Moreover, we showed that PLSR has improved performance over principal component regression (PCR) in the case of multiple tree-ring predictors. According to these results, PLSR may be a preferable method over PCR for the use in automated tree-ring based reconstruction approaches, akin widely used point-by-point regression.
description: Austral summer (DJF) temperature reconstruction for Tierra del Fuego region (73.75–66.75W, 53.75–55.75 S) based on 63 tree-ring width chronologies of Nothofagus pumilio and Nothofagus betuloides. Provided Keywords: Southern Hemisphere, Nothofagus pumilio, Nothofagus betuloides, Dendroclimatology, Southern Atlantic, Partial least squares regression.
DOI: 10.25921/vprg-ks64
title: NOAA/WDS Paleoclimatology - Touchan - Tannourine - CDLI - ITRDB LBN012

description: The first large-scale network of 79 tree-ring chronologies in the Eastern Mediterranean and Near East (EMNE; 33°N–42°N, 21°E–43°E) is described and analyzed to identify the seasonal climatic signal in indices of annual ring width. Correlation analysis and cluster analysis are applied to tree-ring data and gridded climate data to assess the climate signal embedded in the network in preparation for climate field reconstructions and formal proxy/model intercomparison experiments. The lengths of the 79 combined chronologies range from 89 to 990 years. The monthly correlations and partial correlations reveal a pervasive positive association with May, June, and sometimes July precipitation, positive correlations with winter and spring (December through April) temperatures, and negative relationships with May through July temperature, although as expected, there are site-to-site exceptions to these general patterns. Cluster analysis suggests three groups of sites based on their association with climate. The chronologies for the EMNE have coherent seasonal precipitation and temperature signals across a fairly broad geographical domain. The predominant signal is a positive growth response to May–June precipitation. Collectively, the findings suggest that the network can be exploited to develop season-specific field reconstructions of precipitation and drought history in the EMNE.
DOI: 10.25921/v1qy-ky45
title: NOAA/WDS Paleoclimatology - Touchan - Alaçam Mevkii - PINI - ITRDB TUR058

description: The first large-scale network of 79 tree-ring chronologies in the Eastern Mediterranean and Near East (EMNE; 33°N–42°N, 21°E–43°E) is described and analyzed to identify the seasonal climatic signal in indices of annual ring width. Correlation analysis and cluster analysis are applied to tree-ring data and gridded climate data to assess the climate signal embedded in the network in preparation for climate field reconstructions and formal proxy/model intercomparison experiments. The lengths of the 79 combined chronologies range from 89 to 990 years. The monthly correlations and partial correlations reveal a pervasive positive association with May, June, and sometimes July precipitation, positive correlations with winter and spring (December through April) temperatures, and negative relationships with May through July temperature, although as expected, there are site-to-site exceptions to these general patterns. Cluster analysis suggests three groups of sites based on their association with climate. The chronologies for the EMNE have coherent seasonal precipitation and temperature signals across a fairly broad geographical domain. The predominant signal is a positive growth response to May–June precipitation. Collectively, the findings suggest that the network can be exploited to develop season-specific field reconstructions of precipitation and drought history in the EMNE.
DOI: 10.25921/v1vx-1c71
title: NOAA/WDS Paleoclimatology - Modern California Cave Calcium Isotope and Trace Metal Data

description: Variations in speleothem calcium isotope ratios (δ44Ca) are thought to be uniquely controlled by prior carbonate precipitation (PCP) above a drip site and, when calibrated with modern data, show promise as a semi-quantitative proxy for paleorainfall. However, few monitoring studies have focused on δ44Ca in modern cave systems. We present a multi-year comparative study of δ44Ca, carbon isotopes (δ13C), and trace elemental ratios from cave drip waters, modern calcite, and host rocks from two cave systems in California—White Moon Cave (WMC) and Lake Shasta Caverns (LSC). Drip water and calcite δ44Ca from both caves indicate PCP-driven enrichment, and we used a simple Rayleigh fractionation model to quantify PCP variability over the monitoring period. Modern calcite trace element and δ44Ca data positively correlate at WMC, but not at LSC, indicating a shared PCP control on these proxies at WMC but not at LSC. At both WMC and LSC, we observe an inverse relationship between PCP and rainfall amounts, though this relationship is variable across individual drip sites. Our modeled data suggest that WMC experiences ∼20% more PCP than LSC, consistent with the fact that WMC receives less annual rainfall. This work supports speleothem δ44Ca as an independent constraint on PCP that can aid in the interpretation of other hydrologically sensitive proxies and provide quantitative estimates of paleorainfall. Additional, long-term monitoring studies from a variety of climate settings will be key for understanding δ44Ca variability in cave systems more fully and better constraining the relationship between PCP and rainfall.
description: Modern geochemical data to support the paleoclimate data from White Moon Cave found at: https://www.ncei.noaa.gov/access/paleo-search/study/32012. Site locations: White Moon Cave (WMC) 37.02 N, -122.18 W, 167m; Lake Shasta Caverns (LSC) 40.8 N, -122.3 W, 725m
DOI: 10.25921/vhx5-ec09
title: NOAA/WDS Paleoclimatology - Touchan - Taourirt - CDAT - ITRDB MAR044

description: The first large-scale network of tree-ring chronologies from the western Mediterranean (WM; 32°N–43°N, 10°W–17°E) is described and analyzed to identify the seasonal climatic signal in indices of annual ring width. Correlation and rotated empirical orthogonal function analyses are applied to 85 tree-ring series and corresponding gridded climate data to assess the climate signal embedded in the network. Chronologies range in length from 80 to 1129 years. Monthly correlations and partial correlations show overall positive associations for Pinus halepensis (PIHA) and Cedrus atlantica (CDAT) with winter (December–February) and spring (March–May) precipitation across this network. In both seasons, the precipitation correlation with PIHA is stronger, while CDAT chronologies tend to be longer. A combination of positive correlations between growth and winter–summer precipitation and negative partial correlations with growing season temperatures suggests that chronologies in at least part of the network reflect soil moisture and the integrated effects of precipitation and evapotranspiration signal. The range of climate response observed across this network reflects a combination of both species and geographic influences. Western Moroccan chronologies have the strongest association with the North Atlantic Oscillation.
DOI: 10.25921/v4x4-zw83
title: NOAA/WDS Paleoclimatology - Touchan - Oum Djedour - PIHA - ITRDB TUN012

description: The first large-scale network of tree-ring chronologies from the western Mediterranean (WM; 32°N–43°N, 10°W–17°E) is described and analyzed to identify the seasonal climatic signal in indices of annual ring width. Correlation and rotated empirical orthogonal function analyses are applied to 85 tree-ring series and corresponding gridded climate data to assess the climate signal embedded in the network. Chronologies range in length from 80 to 1129 years. Monthly correlations and partial correlations show overall positive associations for Pinus halepensis (PIHA) and Cedrus atlantica (CDAT) with winter (December–February) and spring (March–May) precipitation across this network. In both seasons, the precipitation correlation with PIHA is stronger, while CDAT chronologies tend to be longer. A combination of positive correlations between growth and winter–summer precipitation and negative partial correlations with growing season temperatures suggests that chronologies in at least part of the network reflect soil moisture and the integrated effects of precipitation and evapotranspiration signal. The range of climate response observed across this network reflects a combination of both species and geographic influences. Western Moroccan chronologies have the strongest association with the North Atlantic Oscillation.
DOI: 10.25921/v28e-n640
title: NOAA/WDS Paleoclimatology - Touchan - Bozdağ - PINI - ITRDB TUR064

description: The first large-scale network of 79 tree-ring chronologies in the Eastern Mediterranean and Near East (EMNE; 33°N–42°N, 21°E–43°E) is described and analyzed to identify the seasonal climatic signal in indices of annual ring width. Correlation analysis and cluster analysis are applied to tree-ring data and gridded climate data to assess the climate signal embedded in the network in preparation for climate field reconstructions and formal proxy/model intercomparison experiments. The lengths of the 79 combined chronologies range from 89 to 990 years. The monthly correlations and partial correlations reveal a pervasive positive association with May, June, and sometimes July precipitation, positive correlations with winter and spring (December through April) temperatures, and negative relationships with May through July temperature, although as expected, there are site-to-site exceptions to these general patterns. Cluster analysis suggests three groups of sites based on their association with climate. The chronologies for the EMNE have coherent seasonal precipitation and temperature signals across a fairly broad geographical domain. The predominant signal is a positive growth response to May–June precipitation. Collectively, the findings suggest that the network can be exploited to develop season-specific field reconstructions of precipitation and drought history in the EMNE.