cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/c8ez-6f86
title: NOAA/WDS Paleoclimatology - 1,100 Year El Niño/Southern Oscillation (ENSO) Index Reconstruction

description: The El Niño/Southern Oscillation (ENSO) is the dominant mode of interannual climate variability on Earth, alternating between anomalously warm (El Niño) and cold (La Niña) conditions in the tropical Pacific at intervals of 2-8 years. The amplitude of ENSO variability affects the occurrence and predictability of climate extremes around the world, but our ability to detect and predict changes in ENSO amplitude is limited by the fact that the instrumental record is too short to characterize its natural variability. Here we use the North American Drought Atlas - a database of drought reconstructions based on tree-ring records - to produce a continuous, annually resolved record of ENSO variability over the past 1,100 years. Our record is in broad agreement with independent, ENSO-sensitive proxy records in the Pacific and surrounding regions. Together, these records indicate that ENSO amplitude exhibits a quasi-regular cycle of 50-90 years that is closely coupled to the tropical Pacific mean state. Anomalously warm conditions in the eastern Pacific are associated with enhanced ENSO variability, consistent with model simulations. The quasi-periodic ENSO amplitude modulation reported here offers a key observational constraint for improving models and their prediction of ENSO behaviour linked to global warming.
description: An index of canonical ENSO variability for the past 1,100 years, derived from the first principal component of tree-ring based North America Drought Atlas (NADA). This index comprises interannual ENSO variability only, as a 9-year Lanczos highpass filter was applied on time series at each NADA grid point. A 21-year running biweight variance was calculated to measure changes in ENSO amplitude.
DOI: 10.25921/ctq1-za07
title: NOAA/WDS Paleoclimatology - Lloyd - Sylakh - LAGM - ITRDB RUSS206

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: Site was an old Larix cajanderi stand near the Lena River.  It is located on the floodplain,  with extensive silt deposition and other evidence of annual flooding.  This file contains all of the measured trees.  Trees have been crossdated, but some cores contain persistent problems that were not resolved.  We advise users to examine COFECHA output prior to use-- for climatological studies, users will probably want to eliminate a few cores with persistent problems. 
NOAA Template Raw Measurements file added 2019-04-08.
DOI: 10.25921/cp34-zb62
title: NOAA/WDS Paleoclimatology - Lake Braya Sø, Greenland 7,000 Year Temperature Reconstructions

description: High-resolution paleoclimate reconstructions are often restricted by the difficulties of sampling geologic archives in great detail and the analytical costs of processing large numbers of samples. Using sediments from Lake Braya Sø, Greenland, we introduce a new method that provides a quantitative high-resolution paleoclimate record by combining measurements of the alkenone unsaturation index (UK37) with non-destructive scanning reflectance spectroscopic measurements in the visible range (VIS-RS). The proxy-to-proxy (PTP) method exploits two distinct calibrations: the in situ calibration of UK37 to lake water temperature and the calibration of scanning VIS-RS data to down core UK37 data. Using this approach, we produced a quantitative temperature record that is longer and has 5 times higher sampling resolution than the original UK37 time series, thereby allowing detection of temperature variability in frequency bands characteristic of the AMO over the past 7,000 years.
description: High-resolution temperature reconstructions based on alkenone data and scanning reflectance spectroscopy measurements from sediments collected in Lake Braya Sø, West Greenland.  Free lipids were extracted from core BS01-01, freeze-dried and homogenized. Alkenone samples at 0.5 cm intervals were quantified by gas-chromatography-flame-ionization-detection. The VIS-RS measurements were conducted on an overlapping core (BS03-01) at 2mm intervals.  Relative Absorption Band Depth at 660-760 nm was utilized for the reconstructions. 
Lake Braya Sø, West Greenland: 66°59'15"N, 51°02'0"W, 170m elev, 24m depth
DOI: 10.25921/c4qk-hc86
title: NOAA/WDS Paleoclimatology - Lynch-Stieglitz et al. 2009 Florida Current 8KYr Benthic Isotope Data

description: The density structure across the Florida Straits is reconstructed for the last 8000 years from oxygen isotope measurements on foraminifera in sediment cores. The oxygen isotope measurements suggest that the density contrast across the Florida Current increased over this time period. The magnitude of this change corresponds to an increase in the geostrophic transport referenced to 800 m water depth of 4 sverdrups (Sv) over the last 8000 years. The spatial and seasonal distribution of incoming solar radiation due to changes in the Earth's orbit has caused systematic changes in the atmospheric circulation, including a southward migration of the Intertropical Convergence Zone over the last 8000 years. These changes in atmospheric circulation and the associated wind-driven currents of the upper ocean could readily account for a 4 Sv increase in the strength of the Florida Current. We see no evidence in our data for dramatic changes in the strength of the Atlantic Meridional Overturning Circulation over this time period.
DOI: 10.25921/c0yy-9h89
title: NOAA/WDS Paleoclimatology - Andrews et al. 2009 NW Iceland/Denmark Strait 2KYr Multiproxy Sediment Data

description: MD99-2263 is a 46 cm box core collected from Djupall, a trough that cuts across the NW Iceland Shelf and ends above Denmark Strait. We provide a multiproxy record that documents changes in the regional marine climate over the last ~1700 yr. The depth/age model is based on seven calibrated radiocarbon dates on mollusk shells and on 210Pb and 137Cs. Sediment accumulation rates were variable (0.2—0.8 mm/yr) but increased dramatically ~AD 1500. Grain-size, magnetic properties, quantitative mineral composition of the <2 mm sediment fraction, benthic foraminiferal composition, benthic and planktic Δ18O ratios, and abundances/fluxes of the sea ice biomarker IP25 were determined. To better compare the various proxies, 12 of the critical climate proxies were co-ordinated into 100-yr/sample time series, which were examined by Principal Component Analysis. The 1st axis explained 49% of the variance and the 2nd axis explained an additional 17%. The variables most strongly associated with the 1st axis were sediment properties (phi mean, clay%) and the sea ice biomarker. Mineralogical indicators of drift ice rafting, such as the presence of quartz and potassium- and sodium-feldspars, coincide with the IP25 biomarker data and show an increase after AD 1200, but high values of quartz and some feldspars also occurred between c. AD 300 and 900 with pronounced minima between AD 900 and 1100. Overall, our data suggest a simple two-fold division in climate conditions over the last 1700 yr, with the major change occurring c. AD 1200. In the last few decades, conditions have reverted towards those experienced prior to AD 1200.
DOI: 10.25921/c8h5-3525
title: NOAA/WDS Paleoclimatology - Larocque et al. 2009 Lake Silvaplana 420yr Chironomid Inferred Temperature

description: Chironomids were used to reconstruct mean July air temperatures between c. AD 1580 and 2001 at Lake Silvaplana, a varved lake located in the Engadine, eastern Swiss Alps. The goal of this study was to reconstruct temperature changes at near-annual resolution, and validate the reconstruction by comparison with records based on early instrumental data, documentary proxy evidence, dendrochronology, geochemical (biogenic silica (BSi)) and mineralogical data (quartz/mica ratios) at local and regional scales. Warmer than-the-climate-normal (AD 1961—1990) mean July air temperatures were inferred between c. AD 1610 and 1662, AD 1710 and 1740, AD 1790 and 1866, AD 1940 and 1960 and AD 1990 and 2001. Colder-than-the-climate-normal July air temperatures were reconstructed between c. AD 1662 and 1710, AD 1740 and 1790, AD 1866 and 1919, and AD 1970 and 1990. The 420-year chironomid-inferred mean July air temperature record was significantly (p < 0.01) related to June—September (JJAS) temperatures reconstructed from early instrumental and documentary data at regional scale, JJA temperature inferred from documentary proxy evidence at local scale and summer temperatures based on early instrumental data in central Europe. When the Z-scores of warm/cold periods were compared between records, only one period (c. AD 1740—1790) did not show significant correlations between the chironomid record and any of the eight other records considered here, probably because of increased precipitation and changes in the sediment composition which influenced the chironomid assemblages. 75% of the periods considered had significant correlations between the chironomid records, and both the reconstruction based on quartz/mica ratios and the inferred JJAS early instrumental and documentary proxy evidence, while 60% of the periods showed significant correlations between the chironomid-based record and the reconstruction based on early instrumental data of Central Europe. These results suggest that chironomids in the sediment of Lake Silvaplana yield valid temperature reconstructions at regional scales for the last 420 years.
DOI: 10.25921/c3ah-c727
title: NOAA/WDS Paleoclimatology - Hodell and Venz-Curtis 2006 Late Neogene Southern Ocean Carbon Isotope Data

description: We compiled carbon isotope records from the North Atlantic, South Atlantic, and Pacific oceans to estimate changes in vertical and interbasinal δ13C gradients for the last 9 Myr. Benthic δ13C values of deep water in the South Atlantic decreased in a series of steps at ∼7, 2.75, and 1.55 Ma away from the North Atlantic and toward the Pacific. The benthic δ13C of intermediate water in the South Atlantic evolved differently from deep waters, resulting in an increase in the intermediate-to-deep δ13C gradient (Δ13CID). The Δ13CID increased in steps at ∼2.75 and 1.55 Ma, marking the development and intensification of a chemical divide in the Atlantic Ocean between well-ventilated intermediate water and poorly ventilated deep water. We suggest these changes in interbasinal and vertical gradients resulted from decreasing Northern Component Water and reduced ventilation of Southern Component Water (SCW). The latter was caused by several interrelated processes in Antarctic sources areas, including increased sea ice cover, enhanced surface water stratification, decreased Ekman-induced upwelling, and reduced vertical mixing across the thermocline. Because Antarctic surface water processes and deepwater ventilation rates ultimately influence atmospheric CO2 concentration, these processes may have acted as a positive feedback that contributed to the major cooling steps in late Neogene climate.
DOI: 10.25921/c81y-zb68
title: NOAA/WDS Paleoclimatology - Cosford et al. 2008 Xiangshui, Yaoba Don Caves Glacial Isotope Data

description: Two stalagmites from Xiangshui (X3) and Yaoba Don (YB1) Caves in 
southeastern China provide high-resolution d18O time-series that 
exhibit prominent millennial-scale fluctuations in the intensity 
and character of the Asian monsoon for the period from 20,000 to 
50,000 yr. B.P. Timing of these fluctuations, established by 
U-series disequilibrium (230Th/234U), correlates with Dansgaard-
Oeschger events (2-13) and Heinrich events (H2-H5) recorded in 
the GISP2 ice core, indicating a climatic link between Asian 
monsoon circulation and air temperatures over the North Atlantic 
for much of the last glaciation. Although the exact mechanisms 
linking climatic fluctuations in the North Atlantic to those in 
eastern China have yet to be identified, climatic signals 
associated with changes in global ice volume and air temperatures 
over Greenland may be transferred to Asia by atmospheric mechanisms 
that affect the strength of the Siberian high-pressure cell and the 
amount of snow cover on the Tibetan Plateau, which force the 
intensity of the Asian monsoon.  Another mechanism linking climate 
of the North Atlantic to the Asian monsoon relates to variation in 
oceanic circulation. Millennial-scale fluctuations in thermohaline 
circulation in the North Atlantic may have affected ocean currents 
in the tropical western Pacific Ocean, which is the moisture source 
for the East Asian monsoon.  Despite the similarity of these 
paleoclimatic records and the implication of global teleconnections, 
the magnitude and timing of millennial-scale events at different 
locations in China reveal regional variations in climatic conditions. 
Comparisons of the d18O curves from Xiangshui and Yaoba Don Cave 
stalagmites with those from Qixin Cave and Hulu Cave show general 
concordance between millennial-scale events, albeit with some notable 
differences among all the records. The well-studied Hulu Cave records 
show d18O values that are lower than those of Xiangshui and Yaoba Don 
Caves, reflecting geographical differences. Hulu Cave is located near 
the eastern coast at a relatively low elevation dominated by the East 
Asian monsoon. By comparison, Xiangshui Cave and Yaoba Don Cave are 
further inland on the eastern slope of the Yunnan-Guizhou plateau, 
which receives precipitation from both the East Asian monsoon and 
quasi-stationary frontal systems. Rainfall contributed by the East 
Asian summer monsoon is relatively diminished in this region 
by these geographic and atmospheric circulation conditions, 
resulting in higher d18O values.
description: Stable isotope data from stalagmite X3, Xiangshui Cave, Guangxi Province, and from Stalagmite YB1, Yaoba Don Cave, Hunan Province, southeastern China, as Asian monsoon proxies.

Xiangshui Cave: 25°15'N, 110°55'E, 380m elev. 
Yaoba Don Cave: 28°48'N, 109°50'E, 420m elev.
DOI: 10.15139/s3/ivk8yo
title: Data Management and Sharing Plan for: Development and Assessment of Artificial Intelligence (AI)-Enhanced Pre-treatment Peer-review Process to Improve Patient Safety in Radiation Oncology

description: The Data Management and Sharing Plan describes the scientific data to be generated and/or used in the research and outlines a strategy for managing and sharing project data.
description: Data Management and Sharing Plan
DOI: 10.25921/cz4s-3b16
title: NOAA/WDS Paleoclimatology - Vitas - Sirguske - LADE - ITRDB LITH016

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/cht7-1y45
title: NOAA/WDS Paleoclimatology - Wiles - Son of Repeater - TSME - ITRDB AK129

description: Recent observations of divergence between tree growth at high-latitude sites and temperature, as well as the decline of yellow cedar [Callitropsis nootkatensis (D. Don) Oerst. ex D.P. Little] in southeast Alaska due to warming, emphasize a need to investigate nonstationary climate response of Alaskan coastal forests to warming in other tree species.Comparison of annual tree growth in mountain hemlock [Tsuga mertensiana (Bong.)Carriere] to mean monthly temperature and precipitation data from Sitka, Alaska, from A.D. 1830s to 1990s along an elevational transect reveals nonstationarity in tree growth response to climate that suggests an ongoing biome shift.  We observe a marked weakening in the positive relationship between annual growth and warmer growth season temperatures at low-elevation hemlock sites, and a concurrent increase in growth and sensitivity at higher elevations coupled with increased correlation between growth and April precipitation at all sites along our transects. As previously observed with yellow cedar, the mechanism of the hemlock biome shift may be due to an increased susceptibility of roots to damage from late frosts resulting from earlier seasonal loss of protective snowpack.
description:  NOAA Template Chronology file added 2018-12-20. NOAA Template Raw Measurements file added 2019-02-08.
DOI: 10.25921/cq64-c414
title: NOAA/WDS Paleoclimatology - Indopacific Porites coral Li/Ca, B/Ca, Mg/Ca, Sr/Ca, Ba/Ca, U/Ca, and d11B data, 1994-2010

description: Coral skeletons archive past climate variability with unrivaled temporal resolution. However, extraction of accurate temperature information from coral skeletons has been limited by “vital effects,” which confound, and sometimes override, the temperature dependence of geochemical proxies. We present a new approach to coral paleothermometry based on results of abiogenic precipitation experiments interpreted within a framework provided by a quantitative model of the coral biomineralization process. DeCarlo et al. (2015a) investigated temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater and modeled the sensitivity of skeletal composition to processes occurring at the site of calcification. The model predicts that temperature can be accurately reconstructed from coral skeleton by combining Sr/Ca and U/Ca ratios into a new proxy, which we refer to hereafter as the Sr-U thermometer. Here we test the model predictions with measured Sr/Ca and U/Ca ratios of 14 Porites sp. corals collected from the tropical Pacific Ocean and the Red Sea, with a subset also analyzed using the boron isotope (d11B) pH proxy. Observed relationships among Sr/Ca, U/Ca, and d11B agree with model predictions, indicating that the model accounts for the key features of the coral biomineralization process. By calibrating to instrumental temperature records, we show that Sr-U captures 93% of mean annual temperature variability (26–30°C) and has a standard deviation of prediction of 0.5°C, compared to 1°C using Sr/Ca alone. The Sr-U thermometer may offer significantly improved reliability for reconstructing past ocean temperatures from coral skeletons.
description: Measurement Precision- Mg/Ca 0.05 mmol/mol; Sr/Ca 0.04 mmol/mol; Ba/Ca 0.03 µmol/mol; U/Ca 0.01 µmol/mol; Li/Ca 0.27 µmol/mol; B/Ca 4 µmol/mol; d11B 0.21 per mil SRM 951.
       Provided Keywords: Porites, coral, Sr-U
DOI: 10.15468/dl.5murkb
title: Occurrence Download

description: A dataset containing 100 species occurrences available in GBIF matching the query:
{
 "and" : [
 "TaxonKey is one of (Eriolobus trilobatus)",
 "HasCoordinate is true",
 "HasGeospatialIssue is false"
 ]
}

 The dataset includes 100 records from 12 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0006210-251009101135966/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.
DOI: 10.25921/c12j-xt11
title: NOAA/WDS Paleoclimatology - Southern Hemisphere 1000 Year Temperature Reconstructions

description: The Earth's climate system is driven by a complex interplay of internal chaotic dynamics and natural and anthropogenic external forcing. Recent instrumental data have shown a remarkable degree of asynchronicity between Northern Hemisphere and Southern Hemisphere temperature fluctuations, thereby questioning the relative importance of internal versus external drivers of past as well as future climate variability. However, large-scale temperature reconstructions for the past millennium have focused on the Northern Hemisphere, limiting empirical assessments of inter-hemispheric variability on multi-decadal to centennial timescales. Here, we introduce a new millennial ensemble reconstruction of annually resolved temperature variations for the Southern Hemisphere based on an unprecedented network of terrestrial and oceanic palaeoclimate proxy records. In conjunction with an independent Northern Hemisphere temperature reconstruction ensemble, this record reveals an extended cold period (1594-1677) in both hemispheres but no globally coherent warm phase during the pre-industrial (1000-1850) era. The current (post-1974) warm phase is the only period of the past millennium where both hemispheres are likely to have experienced contemporaneous warm extremes. Our analysis of inter-hemispheric temperature variability in an ensemble of climate model simulations for the past millennium suggests that models tend to overemphasize Northern Hemisphere-Southern Hemisphere synchronicity by underestimating the role of internal ocean-atmosphere dynamics, particularly in the ocean-dominated Southern Hemisphere. Our results imply that climate system predictability on decadal to century timescales may be lower than expected based on assessments of external climate forcing and Northern Hemisphere temperature variations alone.
description: Time series of instrumental and reconstructed Southern Hemisphere spatial mean temperatures 
including 2SE uncertainties and 30-year filtered data.

Also included are the 3000 individual ensemble members of the reconstruction: SH_TT_Recon_ensemble.csv (years in rows, ensemble members in columns).

Also included are time series of proxy data: 
Proxies_SH_recon_screened.csv: lag adjusted and infilled proxy data as used for the reconstructions, scaled to mean 0 and std.dev. 1 over 1911-1990
Proxies_SH_recon_unscreened.csv: Annual proxy data before screening.
DOI: 10.25921/cfq6-a859
title: NOAA/WDS Paleoclimatology - Shao - Wulan WL4 - JUPR - ITRDB CHIN064

description: Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century. At multi-decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them. There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between ad 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century. The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions. Recent warming reversed the long-term cooling; during the period ad 1971-2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years.
description: Purpose of Collection: 
# Climatology - temperature analyses NOAA Template Raw Measurements file added 2019-04-08.