cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/66e1-ag97
title: NOAA/WDS Paleoclimatology - Gavin - Bolton Mountain Low - ACSH - ITRDB VT003

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 2019-02-08.
DOI: 10.25921/6nzq-1b97
title: NOAA/WDS Paleoclimatology - Melvin - Salisbury - QUSP - ITRDB BRIT062

description: We present a millennial long dendroclimatic reconstruction of spring/summer precipitation for southern-central England. Previous research identified a significant moisture stress signal in ring-width data measured from oak trees growing in southern England. In this study, we build upon this earlier work, specifically targeting south-central England, to derive a well replicated oak ring-width composite chronology using both living and historical material.  The data-set includes 352 living trees (AD 1629-2009) and 1540 individual historical series (AD 663-1925). The period expressed by at least 50 trees in any year is AD 980-2009.  Calibration experiments identify the optimal seasonal predictand target as March-July precipitation (1901-2007: r2 = 0.33). However, comparison with the long Kew Gardens precipitation record indicates a weakening in tree-growth/climate response from ~1800 to 1920 which we speculate may be related to smoke and sulphur dioxide (SO2) emissions at that time which may have also contributed to a decrease in tree productivity. The time-series derived using the regional curve standardisation method to capture lower frequency information shows a mediaeval period with alternating multi-decade-long dry and wet periods, with AD 1153-1172 being the wettest reconstructed 20-year period in the whole record. Drier conditions are prevalent from ~1300 to the early sixteenth century followed by a period of increasing precipitation levels. The most recent four centuries of the record appear similar to the mediaeval period with multiple decade-long dry and wet periods. The late twentieth century is the second reconstructed wettest period. These centennial hydroclimatic trends are in broad agreement with independent regional scale hydroclimatic reconstructions from tree-ring (East Anglia), historical, speleothem and peat water level proxy archives in the United Kingdom and appear coupled with reconstructed sea surface temperature changes in the North Atlantic which in turn influence the Atlantic meridional overturning circulation and westerly airflow across the UK.
description: NOAA Template Raw Measurements file added 2019-02-05.
DOI: 10.25921/6ex8-v955
title: NOAA/WDS Paleoclimatology - Lloyd - Yakutsk Upper Terrace - PISY - ITRDB RUSS201

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 2019-04-08.
DOI: 10.25921/63jy-1d34
title: NOAA/WDS Paleoclimatology - Esper - Boibar Valley 1 - JUTU - ITRDB PAKI009

description: We present an analysis of 28 juniper tree-ring sites sampled over the last decades by several research teams in the Tien Shan and Karakorum mountains of western central Asia. Ring-width chronologies were developed on a site-by-site basis, using a detrending technique designed to retain low-frequency climate variations. Site chronologies were grouped according to their distance from the upper timberline in the Tien Shan (~3,400 m a.s.l.) and Karakorum (~4,000 m), and low- and high-elevation composite chronologies combining data from both mountain systems developed. Comparison of these elevational subsets revealed significant coherence (r = 0.72) over the 1438–1995 common period, which is inconsistent with the concept of differing environmental signals captured in tree-ring data along elevational gradients. It is hypothesized that the uniform growth behavior in central Asian juniper trees has been forced by solar radiation variations controlled via cloud cover changes, but verification of this assumption requires further fieldwork. The high-elevation composite chronology was further compared with existing temperature reconstructions from the Karakorum and Tien Shan, and long-term trend differences discussed. We concluded that the extent of warmth during medieval times cannot be precisely estimated based on ring-width data currently available.
description: Purpose of Collection: 
# Dendroclimatology
# 
# Cores and cross-sections are stored at: 
# WSL
#  NOAA Template Raw Measurements file added 2019-04-08.
DOI: 10.25921/68xc-xq57
title: NOAA/WDS Paleoclimatology - Allen - Wey River - PHAS - ITRDB AUSL029

description: Between two and four increment cores were obtained from approximately 20 trees at each of 16 sites of P. aspleniifolius across Tasmania. Four regions were defined and temperature data for climate stations from each of these regions were transformed into dimensionless time series appropriate for each region. The ZI was constructed from Melbourne and Hobart mean sea level pressure (MSLP). Correlations were calculated between climate data and ring widths over most of the 20th century. Data were then segregated into two subperiods to assess whether or not temporal changes in ring width response have occurred over the 20th century.
The dominant feature of the correlation functions was a negative correlation with temperatures of the previous growing season. Correlation between the ZI and ring width is most significant, and positive, in November and March of the previous growing season. Differences in the shape of the correlation functions, and their strength is apparent over the course of the century. In general, correlations have become weaker and less consistent among the 16 sites for the latter part of the century. Temperatures have generally increased during the 1900s over which time period correlations have been calculated.
The temporally changing climatic response in ring widths is consistent with a hypothesis of competition for resources between different parts of a plant. A nonlinear response to climate over a short-time period violates one of the basic assumptions of dendroclimatology, therefore suggesting further investigation of both the physiology of trees used for dendroclimatological purposes and the statistical methods used for climatic reconstruction.
description: NOAA Template Raw Measurements file added 2019-01-24. NOAA Template Raw Measurements file added 2019-02-01.
DOI: 10.25921/628z-7268
title: NOAA/WDS Paleoclimatology - Büntgen - Bakuriani 2 - PISY - ITRDB GEOR003

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 2019-04-08.
DOI: 10.25921/6vg9-8323
title: NOAA/WDS Paleoclimatology - Alla - Nueno - QUFG - ITRDB SPAI066

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 2019-02-05.
DOI: 10.25921/6bc3-sd84
title: NOAA/WDS Paleoclimatology - Unit Lake, Manitoba Holocene Multiproxy Sediment Data

description: The low-Arctic region of western Hudson Bay in interior Canada is one of the most poorly described areas of North America in terms of Holocene climate history. Here, we present new data from a well-dated lake sediment core from northern Manitoba, Canada. We assemble one of the richest multi-proxy datasets to date for a low-Arctic lake and characterize terrestrial and lake processes and exchanges between them. These proxies include fossil pollen and diatom assemblages, charcoal, magnetic properties (susceptibility and remanance), mineral grain size, bulk density, organic-matter content, elemental geochemistry, sediment cation (K+, Mg2+, Ca2+, Fe2+/Fe3+) and macronutrient (P, N, C) contents, biogenic-silica content, basal peat dates (wetland initiation), and stable isotopes (d13C, d15N). The sediment proxies record both broad- and fine-scale (millennial and sub-millennial) climate change. We find indirect evidence for a cool and dry post-glacial period from 9,000 to 6,500 cal yr BP, a warm and moist mid-Holocene period from 6,500 to 2,500 cal yr BP, and a cool and moist late-Holocene period from 2,500 cal yr BP to present. High-resolution geochemical data suggests 300- to 500-year-long dry periods at ~6,500-6,100, 5,300-5,000, 3,300-2,800, and 400-0 cal yr BP. These results suggest that terrestrial and aquatic ecosystem dynamics in the western Hudson Bay region are sensitive to past climate change and are likely to respond to future changes in temperature and precipitation.
description: Multiproxy sediment data from Unit Lake, Manitoba for the past 12,000 years. Paleoenvironmental proxies measured include fossil pollen and diatom assemblages, charcoal, magnetic properties (susceptibility and remanance), mineral grain size, bulk density, organic-matter content, elemental geochemistry, sediment cation (K+, Mg2+, Ca2+, Fe2+/Fe3+) and macronutrient (P, N, C) contents, biogenic-silica content, basal peat dates (wetland initiation), and stable isotopes (d13C, d15N). Unit Lake, Manitoba, Canada: 59.404°N, 97.493°W, 294m elevation, 11m water depth.
DOI: 10.25921/6vtp-ge81
title: NOAA/WDS Paleoclimatology - Subpolar North Atlantic 2000 Year Alkenone SST Reconstruction

description: A decadal resolution time series of sea surface temperature (SST) spanning the last two millennia is reconstructed by combining a proxy record from a new sediment sequence with previously published data from core MD99-2275, north of Iceland. The alkenone based SST reconstruction is validated with historic observational data and compared to a new similar temporal resolution reconstruction obtained from sediment core RAPiD21-3K, in the subpolar North Atlantic. The two SST paleorecords show consistent multidecadal scale coolings throughout the interval and similar expressions during the contrasted climatic periods 'colloquially known' as the Medieval Climatic Anomaly (MCA) and Little Ice Age (LIA). In order to further understand the temporal and spatial SST variations and investigate the influence of natural forcings on the observed SST changes during the last millennium, we compare our time series to simulations using the Institut Pierre-Simon Laplace IPSLCM4-v2 climate model. This comparison highlights the potential importance of volcanism as a natural forcing driving coherent abrupt cooling events captured in the subpolar North Atlantic records.
description: Decadal resolution time series of sea surface temperature (SST) obtained 
from alkenone paleothermometry spanning the last two millennia from core 
MD99-2275 located north of Iceland, in the North Altantic polar front. 

The current MD99-2275 age model is constructed using eight geochemically 
identified tephra layers  [Knudsen et al., 2009, Table 2], 
the 137Cs peak of maximum nuclear testing in 1963 A.D. and the top 
of undisturbed sediment according to 210Pb measurements. 
The top of the spliced cores at site MD99–2275 is assumed at 
2006 ± 1 A.D, and estimation of age model uncertainties for the 
record has been published [Eiríksson et al., 2011]. 
Temporal resolution ranges from 2 to 4 years. 

This reconstruction extends to the present-day the decadal-scale 
alkenone based SST reconstruction earlier published by Sicre et al. 
[Earth Planet. Sci. Lett., 268, 137–142, doi:10.1016/j.epsl.2008.01.011, 
2008a] and Sicre et al. [Quat. Sci. Rev., 27, 2041–2047, 
doi:10.1016/j.quascirev. 2008.08.009, 2008b] 
and now includes the 20th century. 

Overall, this spliced record combines three sediment sequence 
reconstructions with different coring devices (piston, gravity and box) 
in a highly variable region thus represents a unique regional 
reconstruction benchmark.
DOI: 10.25921/60kr-fk43
title: NOAA/WDS Paleoclimatology - Chinese Loess Plateau 60KYr Grain Size Data

description: The last glacial period was characterized by abrupt, millennial-scale climate change. These climate fluctuations are particularly pronounced in records of the East Asian monsoon system, and seem to be linked to changes in North Atlantic circulation. Here we present records of grain size variations from the northwestern Chinese Loess Plateau, dated using optically stimulated luminescence. We reconstruct changes in the strength of the East Asian winter monsoon over the past 60,000 years and find reconstructed millennial-scale variations that are broadly correlated with temperature variations over Greenland, suggesting a common forcing. We investigate the effect of a slow-down of Atlantic meridional overturning circulation on the monsoon system using a coupled climate model simulation with added freshwater flux into the northern North Atlantic, and find a strengthening winter monsoon circulation over the regions that supply dust to the Loess Plateau and a reduction in summer monsoon precipitation over East Asia. We conclude that Atlantic meridional overturning circulation is a driver of abrupt change in the East Asian winter and summer monsoon systems, and that the northern westerlies play a role in transmitting this signal from the North Atlantic to the Asian monsoon regions.
description: Grain size data for the past 60,000 years from 2 loess sections 
in the northwestern Chinese Loess Plateau.  20-m sampling pits 
were excavated at Jingyuan and Gulang, with age models developed 
via 40 optically stimulated luminescence (OSL) measurements. 
Grain size was measured on 2000 samples taken at 2-cm. intervals. 
Grain size data is interpreted as a winter monsoon strength proxy. 

Jingyuan, Chinese Loess Plateau: 36.35°N, 104.6°E,  2210 m elev. 
Gulang, Chinese Loess Plateau:   37.49°N, 102.88°E, 2400 m elev.
DOI: 10.25921/6h7f-m512
title: NOAA/WDS Paleoclimatology - Boswijk - Coutts Chemist Building, Whangarei - AGAU - ITRDB NEWZ113

description: It is not known how global warming will affect the El Niño/Southern Oscillation (ENSO). The instrumental record is too short to discern centennial-scale trends and modelling results are inconclusive1, 2, 3, 4, 5. Proxy reconstructions indicate that ENSO activity was relatively high during the late twentieth century6, 7, 8, 9, 10, but whether this was unusual in the millennial context remains uncertain. Here we present insights into these issues derived from rings of the kauri tree (Agathis australis), a rare long-lived conifer endemic to the forests of northern New Zealand. Our results indicate that the twentieth century was the most ‘ENSO-active’ century of the past 500 years, but may not be unique in the context of the past 700 years, and that ENSO activity comparable to or elevated above that experienced during the late twentieth century is plausible under warmer-than-present conditions. We also find evidence that there may have been significant changes in the ENSO teleconnection to the New Zealand region during the fourteenth and fifteenth centuries, and of multi-decadal fluctuations in ENSO-related activity building up to the present day. Although these two features may delay the expression of increased ENSO activity in the New Zealand region, our results indicate that New Zealand climate is likely to be more dominated by ENSO-related inter-annual variability as the world continues to warm.
description: NOAA Template Raw Measurements file added 2019-02-01.
DOI: 10.25921/6ryq-hk78
title: NOAA/WDS Paleoclimatology - Blair and Watkins 2009 Late Cretaceous Calcareous Nannofossils

description: The Ten Mile Creek area (Dallas, Texas) is a proposed Global Stratotype Section and Point (GSSP) candidate for the Coniacian/Santonian Stage boundary. The Santonian Working Group has designated the first appearance of Inoceramus (Cladoceramus) undulatoplicatus as the diagnostic macrofossil bioevent for the base of the Santonian Stage. Calcareous nannofossils were examined from sediments of the Bruceville Marl at the proposed GSSP site and from well-preserved sediments of the coeval Smoky Hill Member-type area (northwestern Kansas) of the Niobrara Formation. Nannofossil bioevents were correlated with the lowest stratigraphic occurrence of I. undulatoplicatus to create a high resolution biostratigraphic framework and stratigraphic proxy for the Coniacian/Santonian Stage transition.

Six bioevents are useful for recognition of the Coniacian/Santonian transition within the Bruceville Marl and Smoky Hill Member. The first appearance datums (FADs) of Prediscosphaera desiderograndis, n. sp. and Amphizygus megalops, n. sp. as well as the FADs of two rare taxa, Orastrum campanensis and Tortolithus dodekachelyon, n. sp., are in close stratigraphic proximity to the lowest occurrence of I. undulatoplicatus. In addition, two nannofloral acmes occur near the boundary: Watznaueria quadriradiata and Zeugrhabdotus scutula.

This study describes eight new species from the Smoky Hill Chalk type area; Amphizygus megalops, Bifidalithus phenax, Pharus evanescens, Gartnerago margaritatus, Helicolithus tectufissus, Tortolithus dodekachelyon, Prediscosphaera desiderograndis and Helicolithus varolii. Light microscope images are provided for rare and well-preserved specimens of Reinhardtites clavicaviformis Varol, 1991, Orastrum campanensis (Cepek) Wind & Wise, 1977, Rhombolithus rhombicum (Bukry) Black, 1973, and Gartnerago clarusora Varol, 1991. This study extends the ranges of several species from those documented in previous literature.
DOI: 10.25921/6dqm-mc20
title: NOAA/WDS Paleoclimatology - Kurek et al. 2009 Alaska 39KYr Midge-Inferred July Temperature

description: Fossil Chironomidae assemblages (with a few Chaoboridae and Ceratopogonidae) from Zagoskin and Burial Lakes in western Alaska provide quantitative reconstructions of mean July air temperatures for periods of the late-middle Wisconsin (∼39,000–34,000 cal yr B.P.) to the present. Inferred temperatures are compared with previously analyzed pollen data from each site summarized here by indirect ordination. Paleotemperature trends reveal substantial differences in the timing of climatic warming following the late Wisconsin at each site, although chronological uncertainty exists. Zagoskin Lake shows early warming beginning at about 21,000 cal yr B.P., whereas warming at Burial Lake begins ∼4000 years later. Summer climates during the last glacial maximum (LGM) were on average ∼3.5 °C below the modern temperatures at each site. Major shifts in vegetation occurred from ∼19,000 to 10,000 cal yr B.P. at Zagoskin Lake and from ∼17,000 to 10,000 cal yr B.P. at Burial Lake. Vegetation shifts followed climatic warming, when temperatures neared modern values. Both sites provide evidence of an early postglacial thermal maximum at ∼12,300 cal yr B.P. These chironomid records, combined with other insect-based climatic reconstructions from Beringia, indicate that during the LGM: (1) greater continentality likely influenced regions adjacent to the Bering Land Bridge and (2) summer climates were, at times, not dominated by severe cold.
DOI: 10.25921/6nm6-2c24
title: NOAA/WDS Paleoclimatology - Marchitto et al. 2007 Baja California 38KYr Radiocarbon Activity Reconstruction

description: We reconstructed the radiocarbon activity of intermediate waters in the eastern North Pacific over the past 38,000 years. Radiocarbon activity paralleled that of the atmosphere, except during deglaciation, when intermediate-water values fell by more than 300 per mil. Such a large decrease requires a deglacial injection of very old waters from a deep-ocean carbon reservoir that was previously well isolated from the atmosphere. The timing of intermediate-water radiocarbon depletion closely matches that of atmospheric carbon dioxide rise and effectively traces the redistribution of carbon from the deep ocean to the atmosphere during deglaciation.
DOI: 10.25921/6shm-3x91
title: NOAA/WDS Paleoclimatology - Cosford et al. 2008 Lianhua Cave Holocene Stable Isotope Data

description: Carbon isotopes in speleothems may serve as indicators of vegetative change, climatic conditions, and karst processes. In many recent studies of Chinese stalagmites, however, carbon isotopes have often been neglected or underutilized in interpreting paleoenvironments. Here, we present a continuous decadal-scale d13C record (819 measurements) of the mid- to late-Holocene from a precisely-dated (10 230Th dates) aragonite stalagmite from Lianhua Cave, Hunan Province, China. Compared to coeval stalagmites from other Chinese caves, the average d13C value (-3.6‰) of stalagmite A1 is higher by ~2-7‰. Variations in the d13C values (0.1‰ to -6.0‰) reflect changes in both vegetative productivity and inorganic processes, which respond to climatic processes. The d13C record of stalagmite A1 can be subdivided into three intervals: 1) warm-humid stage (6.6 to 3.8 ka); 2) transitional stage (3.8 to 1.6 ka); and 3) cool-arid stage (1.6 ka to present). Comparisons with other stalagmite and paleoclimatic records demonstrate that these intervals are generally consistent with changes in regional vegetation and climatic conditions.
description: High-resolution stable isotope data for the mid and late Holocene from Stalagmite A1, Lianhua Cave, Longshan County, Hunan Province, China.  The stable isotope data record variations in the East Asian monsoon over the past 6,600 years. Lianhua Cave: 109°32'E, 29°29'N, 455m elevation