cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/hty1-nj90
title: NOAA/WDS Paleoclimatology - Foy Lake, Montana 13,000 Year Diatom-inferred Drought Data

description: Time series analysis of a diatom-inferred drought record suggests that Holocene hydroclimate of the northern Rocky Mountains has been characterized by oscillation between two mean climate states. The dominant climate state was initiated at the onset of the Holocene (ca. 11 ka); under this climate state, drought was strongly cyclic, recurring at frequencies that are similar to twentieth century multidecadal phase changes of the Pacific Decadal Oscillation. This pattern remained consistent throughout much of the mid-Holocene, continuing until ca. 4.5 ka. After this time the mean climate state changed, and drought recurrence became unstable; periods of cyclic drought alternated with periods of less predictable drought. The timing of this shift in climate was coincident with widespread severe drought in the mid-continent of North America. Overall, the strongest periodicity in severe drought occurred during the mid-Holocene, when temperatures in the northern Rocky Mountains were warmer than today.
description: Diatom and sediment chemistry data from Foy Lake, Montana, USA, interpreted as a proxy for drought in mid-continent North America over the Holocene.
DOI: 10.25921/hrv9-s569
title: NOAA/WDS Paleoclimatology - Houbihu, southern Taiwan Porites Sr/Ca and d18O data from 1788 to 2013

description: Reconstructions of key climate parameters prior to anthropogenic influences serve to constrain decadal to multicentury natural climate variability. In the western Pacific region, relatively few reconstructions exist north of the Western Pacific Warm Pool (WPWP), a region critical to global climate. In this study, we collected a coral core from Houbihu, southern Taiwan, and generated a 225-year reconstruction of annual and wintertime sea surface temperature, dry season sea surface salinity, and wet season rainfall records derived from paired Porites Sr/Ca and δ18O profiles extending back to the end of the Little Ice Age (1850 CE). Multidecadal sea surface temperature trends generally track regional surface temperature reconstructions, indicating the dominant influence of solar and volcanic radiative forcings. Reconstructed dry season sea surface salinity reflects an advection signal linked to the East Asian Winter Monsoon and the Pacific Decadal Oscillation, both influencing variations in the Kuroshio Intrusion across the Luzon Strait. Reconstructed wet season rainfall, on the other hand, reveals influence of the Pacific Decadal Oscillation on the decadal variability of local and regional rainfall patterns. Relative to the late 1900s, our climate reconstructions document cooler and drier (high salinity and low rainfall) conditions during the end of the Little Ice Age, supporting other lines of evidence of a retracted WPWP region during this period. In the late 20th to early 21st century, our climate reconstructions record warming and freshening (low salinity and high rainfall) trends, highlighting the potential impact of anthropogenic forcing in the extension of the WPWP.
description: Monthly paired Porites Sr/Ca and d18O measurements
DOI: 10.25921/h8cy-p037
title: NOAA/WDS Paleoclimatology - GISP2 Ice Core 50KYr Accumulation Rate History

description: We present a combined heat- and ice-flow model, constrained by measurements of temperature in the Greenland Ice Sheet Project 2 (GISP2) borehole and by the GISP2 d18O record and depth-age scale, which determines a history of temperature, accumulation rate, and ice sheet elevation for the past 50,000 years in central Greenland. Important results are: that the temperature increase from average glacial to Holocene conditions was large, approximately 15C, with a 20C warming from late glacial to Holocene; that the average accumulation rate during the last glacial maximum (between 15 and 30 kyr B. P.) was 5.5 to 7 cm yr-1, approximately 25% of the modern accumulation rate; that long-term (500-1000 years) averaged accumulation rate and temperature have been inversely correlated during the most recent 7 millennia of the Holocene; and that the Greenland Ice Sheet probably thickened during the deglacial transition. The inverse correlation of accumulation rate and temperature in the mid and late Holocene suggests that the Greenland Ice Sheet is more prone to volume reduction in a warmed climate than previously thought and demonstrates that accumulation rate is not a reliable proxy for temperature. The elevation history of the ice sheet is poorly constrained by the model, and independent evidence is needed. We also present a simple estimate of the response time for thinning of the interior region of an ice sheet due to retreat of its margins. This was approximately 1900 years for central Greenland during deglaciation.
description: History of accumulation rate at GISP2, three versions corresponding to three different ice dynamics situations.
DOI: 10.25921/hnaw-me72
title: NOAA/WDS Paleoclimatology - GISP2 Ice Core 112KYr Methane Concentration Data

description: A methane record from the GISP2 ice core reveals that millennial-scale variations in atmospheric methane concentration characterized much of the past 110,00 years. As previously observed in a shorter record from central Greenland, abrupt concentration shifts of about 50 to 300 parts per billion by volume were coeval with most of the interstadial warming events (better known as Dansgaard-Oeschger events) recorded in the GISP2 ice core throughout the last glacial period. The magnitude of the rapid concentration shifts varied on a longer time scale in a manner consistent with variations in Northern Hemisphere summer insolation, which suggests that insolation may have modulated the effects of interstadial climate change on the terrestrial biosphere.
description: Gas ages were calculated according to the methods described in Brook et al. 1996, and are subject to change.  Ice ages were calculated by linear interpolation from the Meese et al. timescale.
DOI: 10.25921/hxkq-9188
title: NOAA/WDS Paleoclimatology - Yocom fire data from Las Manzanas, Sierra Madre Oriental, Coahuila, Mexico - IMPD MXLM-001

description: We investigated the influence of broad- v. fine-scale factors on fire in an unusual landscape suitable for distinguishing the drivers of fire synchrony. Our study was conducted in the Sierra Madre Oriental mountain range, in north-eastern Mexico. We worked in nine sites on three parallel mountains that receive nearly identical broad-scale climatic influence, but between which fires are unlikely to spread. We collected and cross dated samples from 357 fire-scarred trees in nine sites in high-elevation mixed-conifer forests and identified fire dates. We used Jaccard similarity analysis to evaluate synchrony among sites and quantified relationships between climate and fire occurrence. Fires were historically frequent (mean fire interval ranged from 8 to 16 years in all sites) and dates of fire exclusion ranged from 1887 to 1962. We found low fire synchrony among the three mountains, indicating a strong influence of fine-scale factors on fire occurrence. Fire regime attributes were similar across mountains despite the independence of fire dates. La Niña events were associated with fire over time, although not significantly since the 1830s. Our results highlight the importance of scale in describing fire regimes and suggest that we can use fire history to understand controls on complex ecosystem processes and patterns.
description: This site was sampled as part of a project to reconstruct historical fire regimes in northeastern Mexico. Ring-boundary fire scars were assigned to the subsequent calendar year.

Fire History Graphs: Fire History Graphs illustrate specific years when fires occurred and how many trees were scarred. They are available in both PDF and PNG formats. The graphs consist of 2 parts, both of which show the X axis (time line) at the bottom with the earliest year of information on the left and the latest on the right. The Fire Index Plot is the topmost plot, and shows two variables: sample depth (the number of recording trees in each year) as a blue line along the left Y axis, compared with the percent trees scarred shown as gray bars along the right Y axis. Below, the Fire Chronology Plot consists of horizontal lines representing injuries by year on individual sampled trees. Symbols are overlain that denote the years containing the dendrochronologically-dated fire scars or injuries. The sample ID of each tree is displayed to the right of each line. The Composite Axis below represents the composite information from all individual series. The symbols used to represent the fire scars or injuries, and the filters used to determine the composite information, are shown in the legend. These graphs were created using the Fire History Analysis and Exploration System (FHAES). See http://www.fhaes.org for more information.
DOI: 10.25921/h3bj-0831
title: NOAA/WDS Paleoclimatology - Smith - Mount Cain - TSME - ITRDB CANA471

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.
DOI: 10.25921/h0qt-j352
title: NOAA/WDS Paleoclimatology - Smith - Cathedral Glacier - ABLA - ITRDB CANA492

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/h7b7-qh88
title: NOAA/WDS Paleoclimatology - Kuniholm - Acemhoyuk - JUSP - ITRDB TURK044

description: 500 years of ancient Near Eastern history from the earlier second millennium BCE, including such pivotal figures as Hammurabi of Babylon, Šamši-Adad I (who conquered Aššur) and Zimrilim of Mari, has long floated in calendar time subject to rival chronological schemes up to 150+ years apart. Texts preserved on clay tablets provide much information, including some astronomical references, but despite 100+ years of scholarly effort, chronological resolution has proved impossible. Documents linked with specific Assyrian officials and rulers have been found and associated with archaeological wood samples at Kültepe and Acemhöyük in Turkey, and offer the potential to resolve this long-running problem. Here we show that previous work using tree-ring dating to place these timbers in absolute time has fundamental problems with key dendrochronological crossdates due to small sample numbers in overlapping years and insufficient critical assessment. To address, we have integrated secure dendrochronological sequences directly with radiocarbon (14C) measurements to achieve tightly resolved absolute (calendar) chronological associations and identify the secure links of this tree-ring chronology with the archaeological-historical evidence. The revised tree-ring-sequenced 14C time-series for Kültepe and Acemhöyük is compatible only with the so-called Middle Chronology and not with the rival High, Low or New Chronologies. This finding provides a robust resolution to a century of uncertainty in Mesopotamian chronology and scholarship, and a secure basis for construction of a coherent timeframe and history across the Near East and East Mediterranean in the earlier second millennium BCE. Our re-dating also affects an unusual tree-ring growth anomaly in wood from Porsuk, Turkey, previously tentatively associated with the Minoan eruption of the Santorini volcano. This tree-ring growth anomaly is now directly dated ~1681-1673 BCE (68.2% highest posterior density range), ~20 years earlier than previous assessments, indicating that it likely has no association with the subsequent Santorini volcanic eruption.
description: The absolute dates (BCE) in the top header represent the mean of the 14C-calibrated dates with a 2-sigma range (see Figure 6 in Manning et al. 2016 PLOS One).  The three data sets from those sites crossdate with each other and the Relative Years (RY) of the data sets were determined by those crossdates (stated as a Middle Bronze Age, MBA, chronology in Manning et al. 2016).  The absolute dates were determined by the tree-ring sequenced "wiggle matching" of a series of 14C ages on segments of wood with known relative positions and spacing in the Acemhoyuk, Kultepe and Karahoyuk tree-ring chronologies. NOAA Template Raw Measurements file added 2019-02-05.
DOI: 10.25921/h9vs-3747
title: NOAA/WDS Paleoclimatology - Mundo fire data from Sendero Laguna Torre, Patagonia - IMPD ARTOR001

description: Fire is a major disturbance affecting forests worldwide with significant economic, social and ecological impacts. The southernmost forests on Earth extend continuously along the Andes from mid- to subantarctic latitudes in South America. In this region, warming and drying trends since the mid-20th century have been linked to a positive trend in the Southern Annual Mode (SAM), the leading mode of extratropical climate variability in the Southern Hemisphere. Due to the scarcity of documentary fire records and the lack of tree-ring fire histories, little is known about how wildfire activity responds to shifts in the westerly circulation pattern and associated climatic variability in the Andean region south of c. 44°S. For the first time, we applied dendrochronological techniques to reconstruct fire history from the angiosperm Nothofagus pumilio at 16 sites distributed from c. 44 to 50oS to determine relationships between fire occurrence and the two primary drivers of wildfire activity: climate variability and human activities. Partial cross-sections with fire-scars were collected from 363 trees in Argentina and Chile. Chronologies of annually resolved fire-scar dates start in 1791 and show a pattern of higher fire frequency during the 20th century, concurrent with the human occupation and colonization processes in southern Patagonia. Years of widespread fire occurring synchronously in two or more disjunct sites are associated with broad-scale climatic anomalies. Intense droughts inferred from extreme departures in temperature, precipitation and the Standardized Precipitation-Evapotranspiration Index (SPEI) during the growing seasons of 1944 and 1962 are consistent with the two most severe fires at northern sites. Extended droughts, reflected by the association of fire occurrence with 6-month cumulative precipitation and SPEI, create conditions for widespread fires at the southern sites (south of c. 46°S). Regional fires were concurrent with significant positive departures of SAM during the austral spring-summer. This tree-ring fire record reveals the influences of both climate variability and human activities on fire in the N. pumilio forests across the Andes, and also establishes the feasibility of using this tree species as a natural archive of fire history.
DOI: 10.25921/hqcg-gy96
title: NOAA/WDS Paleoclimatology - Wache, Bhutan 269 Year Tree Ring Oxygen Isotope Data

description: We developed a 50-year tree ring d18O chronology for each of three tree species (Juniperus indica, Larix griffithii, and Picea spinulosa) using a total of 12 trees (four trees per species) from the Bhutan Himalaya. Despite originating from different species sampled at two different altitudes, the d18O chronologies are highly correlated with one another (r = 0.76-0.89). Response analyses reveal that tree ring d18O values are controlled mainly by summer precipitation, irrespective of species. Based on these results, a robust 269-year d18O chronology was established to reconstruct the amount of May-September precipitation based on data from four larch trees. Our tree ring d18O data show significant correlations with those from other regions of the Himalaya and the Tibetan Plateau, indicating that common signals related to monsoon activity are recorded in the data. However, at centennial timescales, our data from Bhutan show normal conditions during the 20th century, whereas records from sites in western Nepal and the southern/eastern Tibetan Plateau show weakening trends in monsoon intensity during the last 100-200 years; the weakening trends may be the result of a reduction in the meridional sea surface temperature gradient in the Indian Ocean during this time. At continental scales, the tree ring records show that areas more from ocean basins are particularly sensitive to reduced monsoon circulation. Correlation analyses suggest that the El Niño-Southern Oscillation (ENSO) plays an important role in modulating summer precipitation. However, the teleconnected relationship disappears during the period 1951-1970, coinciding with a negative phase of the Pacific Decadal Oscillation (PDO), implying interdecadal modulation of the PDO on the influence of the ENSO on precipitation in Bhutan.
description: Larix griffithii tree-ring oxygen isotope (d18O) data from Wache, Lunana, Bhutan, for the past 269 years. IITRDB27
DOI: 10.25921/hm90-fk90
title: NOAA/WDS Paleoclimatology - Brubaker - Kamiak Butte - PIPO - ITRDB WA012

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 Chronology file added 2018-12-20. NOAA Template Raw Measurements file added 2019-02-08.
DOI: 10.25921/hy49-yn34
title: NOAA/WDS Paleoclimatology - Jansma - Deventer Ship Timbers used as Rivetments - QUSP - ITRDB NETH003

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 Chronology file added 2018-12-19. NOAA Template Raw Measurements file added 2019-02-05.
DOI: 10.25921/hx6d-3k73
title: NOAA/WDS Paleoclimatology - Schweingruber - Tua Steinkier - PISY - ITRDB NORW002

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 Chronology file added 2019-01-08. NOAA Template Raw Measurements file added 2019-02-05.
DOI: 10.25921/h83r-jy41
title: NOAA/WDS Paleoclimatology - Porter - Porcupine River Downstream site DP30 - PCGL - ITRDB CANA536

description: We present a new 23-site network of white spruce ring-width chronologies near boreal treeline in Old Crow Flats, Yukon Territory, Canada. Most chronologies span the last 300 years and some reach the mid-16th century. The chronologies exhibit coherent growth patterns before the 1930s. However, since the 1930s, they diverge in trend and exhibit one of two contrasting, but well-replicated patterns we call Group 1 and Group 2. Over the instrumental period (1930-2007) Group 1 sites were inversely correlated with previous-year July temperatures while Group 2 sites were positively correlated with growth-year June temperatures. At the broader northwestern North America (NWNA) scale, we find that the Group 1 and Group 2 patterns are common to a number of white spruce chronologies, which we call NWNA 1 and NWNA 2 chronologies. The NWNA 1 and NWNA 2 chronologies also share a single coherent growth pattern prior to their divergence (ca. 1950s). Comparison of the NWNA 1/NWNA 2 chronologies against gridded 20th-century temperatures for NWNA and reconstructed northern hemisphere summer temperatures (ad 1300-2000) indicates that all sites responded positively to temperature prior to the mid-20th century (at least back to ad 1300), but that some changed to a negative response (NWNA 1) while others maintained a positive response (NWNA 2). The spatial extent of divergence implies a large-scale forcing. As the divergence appears to be restricted to the 20th century, we suggest that the temperature response shift represents a moisture stress caused by an anomalously warm, dry 20th-century climate in NWNA, as indicated by paleoclimatic records. However, because some sites do not diverge and are located within a few kilometres of divergent sites, we speculate that site-level factors have been important in determining the susceptibility of sites to the large-scale drivers of divergence.
description: NOAA Template Raw Measurements file added 2019-01-27. NOAA Template Raw Measurements file added 2019-02-04.
DOI: 10.25921/h8ym-b290
title: NOAA/WDS Paleoclimatology - Ferrigno, West Antarctica 300 Year Ice Core Deuterium Data

description: We present a new stable isotope record from Ellsworth Land which provides a valuable 308 year record (1702-2009) of climate variability from coastal West Antarctica. Climate variability at this site is strongly forced by sea surface temperatures and atmospheric pressure in the tropical Pacific and related to local sea ice conditions. The record shows that this region has warmed since the late 1950s, at a similar magnitude to that observed in the Antarctic Peninsula and central West Antarctica; however, this warming trend is not unique. More dramatic isotopic warming (and cooling) trends occurred in the mid-nineteenth and eighteenth centuries, suggesting that at present, the effect of anthropogenic climate drivers at this location has not exceeded the natural range of climate variability in the context of the past ~300 years.
description: Ice Core deuterium (dD) data from the Ferrigno F10 ice core, West Antarctica.