cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/er8m-d641
title: NOAA/WDS Paleoclimatology - Lake Winnipeg, Eastern Canadian Prairies 1000-year Record of Dry Conditions From Oxygen and Carbon Isotope Data

description: A short sediment core (162 cm), covering the period AD 920–1999, was sampled from the south basin of Lake Winnipeg for a suite of multi-proxy analyses leading towards a detailed characterisation of the recent millennial lake environment and hydroclimate of southern Manitoba, Canada. Information on the frequency and duration of major dry periods in southern Manitoba, in light of the changes that are likely to occur as a result of an increasingly warming atmosphere, is of specific interest in this study. Intervals of relatively enriched lake sediment cellulose oxygen isotope values (δ18Ocellulose) were found to occur from AD 1180 to 1230 (error range: AD 1104–1231 to 1160–1280), 1610–1640 (error range: AD 1571–1634 to 1603–1662), 1670–1720 (error range: AD 1643–1697 to 1692–1738) and 1750–1780 (error range: AD 1724–1766 to 1756–1794). Regional water balance, inferred from calculated Lake Winnipeg water oxygen isotope values (δ18Oinf-lw), suggest that the ratio of lake evaporation to catchment input may have been 25–40% higher during these isotopically distinct periods. Associated with the enriched δ18Ocellulose intervals are some depleted carbon isotope values associated with more abundantly preserved sediment organic matter (δ13COM). These suggest reduced microbial oxidation of terrestrially derived organic matter and/or subdued lake productivity during periods of minimised input of nutrients from the catchment area. With reference to other corroborating evidence, it is suggested that the AD 1180–1230, 1610–1640, 1670–1720 and 1750–1780 intervals represent four distinctly drier periods (droughts) in southern Manitoba, Canada. Additionally, lower-magnitude and duration dry periods may have also occurred from 1320 to 1340 (error range: AD 1257–1363), 1530–1540 (error range: AD 1490–1565 to 1498–1572) and 1570–1580 (error range: AD 1531–1599 to 1539–1606).
DOI: 10.25921/e3h7-g704
title: NOAA/WDS Paleoclimatology - Western Australia 40,000 Year Stalagmite Stable Isotope Data

description: Recent studies of stalagmites from the Southern Hemisphere tropics of Indonesia reveal two shifts in monsoon activity not apparent in records from the Northern Hemisphere sectors of the Austral-Asian monsoon system: an interval of enhanced rainfall at ~19 ka, immediately prior to Heinrich Stadial 1, and a sharp increase in precipitation at ~9 ka. Determining whether these events are site-specific or regional is important for understanding the full range of sensitivities of the Austral-Asian monsoon. We present a discontinuous 40 kyr carbon isotope record of stalagmites from two caves in the Kimberley region of the north-central Australian tropics. Heinrich stadials are represented by pronounced negative carbon isotopic anomalies, indicative of enhanced rainfall associated with a southward shift of the intertropical convergence zone and consistent with hydroclimatic changes observed across Asia and the Indo-Pacific. Between 20 and 8 ka, however, the Kimberley stalagmites, like the Indonesian record, reveal decoupling of monsoon behavior from Southeast Asia, including the early deglacial wet period (which we term the Late Glacial Pluvial) and the abrupt strengthening of early Holocene monsoon rainfall.
description: Stable isotope (d18O and d13C) data from stalagmites collected in 2 caves (Ball Gown Cave and Cave KNI-51) in tropical Western Australia for the past 40,000 years.  Kimberley composite stalagmite record utilized in Denniston et al. 2017 Late Glacial through Holocene paleomonsoon reconstruction.
DOI: 10.25921/emnw-ch67
title: NOAA/WDS Paleoclimatology - De Rif, South Africa Holocene Hyrax Midden Stable Isotope Data

description: Climate change during the last deglaciation was strongly influenced by the 'bipolar seesaw', producing antiphase climate responses between the North and South Atlantic. However, mounting evidence demands refinements of this model, with the occurrence of abrupt events in southern low to mid latitudes occurring in-phase with North Atlantic climate. Improved constraints on the north-south phasing and spatial extent of these events are therefore critical to understanding the mechanisms that propagate abrupt events within the climate system. We present a 19,400 year multi-proxy record of climate change obtained from a rock hyrax midden in southernmost Africa. Arid anomalies in phase with the Younger Dryas and 8.2 ka events are apparent, indicating a clear shift in the influence of the bipolar seesaw, which diminished as the Earth warmed, and was succeeded after ~14.6 ka by the emergence of a dominant interhemispheric atmospheric teleconnection.
description: Please contact principle investigator Brian Chase to obtain these data. 

Stable nitrogen (d15N) and carbon (d13C) isotope data obtained from the De Rif rock hyrax (Procavia capensis) midden in the Cederberg Mountains of South Africa's Western Cape. d15N is interpreted as a proxy for aridity, with higher values reflecting an enrichment of 15N in soils under drier conditions
DOI: 10.25921/e65m-z530
title: NOAA/WDS Paleoclimatology - McMurdo Sound, Antarctica, Eocene-Miocene Aragonite Cement Isotope Data

description: Inorganic aragonite occurs in a wide spectrum of depositional environments and its precipitation is controlled by complex physio-chemical factors. This study investigates diagenetic conditions that led to aragonite cement precipitation in Cenozoic glaciomarine deposits of McMurdo Sound, Antarctica. A total of 42 sandstones that host intergranular cement were collected from the CIROS-1 core, located proximal to the terminus of Ferrar Glacier. Standard petrography, Raman spectroscopy and electron microprobe analysis reveal a prominent aragonite cement phase that occurs as a pore-filling blocky fabric throughout the core. Oxygen isotope compositions (d18O = -30.0 to -8.6 permil Vienna Pee-Dee Belemnite) and clumped isotope temperatures (TDelta47 = 13.1 to 31.5C) determined from the aragonite cements provide precise constraints on isotopic compositions (d18Ow) of the parent fluid, which mostly range from -10.8 to -7.2 permil Vienna Standard Mean Ocean Water. The fluid d18Ow values are consistent with those of pore water, previously identified as cryogenic brine in the nearby AND-2A core. Petrographic and geochemical data suggest that aragonite cement in the CIROS-1 core precipitated from a similar brine. The brine likely formed and infiltrated sediments in flooded glacial valleys along the western margin of McMurdo Sound during the middle Miocene Climatic Transition, and subsequently flowed basinward in the subsurface. Consequently, the brine forms as a longstanding subsurface fluid that has saturated Cenozoic sediments below southern McMurdo Sound since at least the middle Miocene. Aragonite cementation in the CIROS-1 core is interpreted to reflect its proximal position to sites of brine formation and greater likelihood of experiencing brines with sustained high carbonate saturation states and Mg/Ca ratios. This unusual occurrence expands the range of known natural occurrences of aragonite cement. Given the potential for cryogenic brine formation in glaciomarine settings, blocky aragonite, as the end member of the spectrum of aragonite cement morphology, may be more widespread in glaciomarine sediments than currently thought.
description: McMurdo Sound, Antarctica, Isotopic analysis of aragonite cement, uppermost Eocene through lower Miocene
DOI: 10.25921/efe4-hs59
title: NOAA/WDS Paleoclimatology - Therrell - Kankakee River State Park - QUAL - ITRDB IL020

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: Kankakee River State Park, 2014, Q. alba NOAA Template Raw Measurements file added 2020-03-09.
DOI: 10.25921/ez97-zw87
title: NOAA/WDS Paleoclimatology - Gulf of California foraminifera and wood 14C (radiocarbon) from 27 to 9 ka

description: Geologic carbon from seafloor volcanism may influence late Pleistocene glacial terminations by increasing the global inventory of the greenhouse gas CO2. However, the evidence for geologic carbon flux associated with deep sea volcanism has been, so far, equivocal. Here, we construct a regional, glacial-deglacial carbon budget of the volcanically active Gulf of California using microfossil 14C measurements and find results consistent with an increased addition of geologic carbon related to local seafloor volcanism during the deglaciation. Our estimates point to enhanced geologic carbon flux both before and during the last deglaciation that generally occur alongside carbonate preservation. This leads us to suggest that the carbon was added in the form of partially neutralized, 14C-free bicarbonate associated with known Gulf sedimentary processes—a carbon source that would have a minimal effect on atmospheric CO2.
description: Marine sediment microfossil (foraminifera) and wood 14C content (radiocarbon) data. Chronology uses wood 14C age, constrained by atmospheric 14C via IntCal13. Published in Rafter et al. (2018) Climate of the Past
DOI: 10.25921/ejde-8240
title: NOAA/WDS Paleoclimatology - Patriot Hills, West Antarctica 135,000 Year Blue Ice Isotope Data

description: The future response of the Antarctic ice sheet to rising temperatures remains highly uncertain. A useful period for assessing the sensitivity of Antarctica to warming is the Last Interglacial (LIG) (129 to 116 ky), which experienced warmer polar temperatures and higher global mean sea level (GMSL) (+6 to 9 m) relative to present day. LIG sea level cannot be fully explained by Greenland Ice Sheet melt (~2 m), ocean thermal expansion, and melting mountain glaciers (~1 m), suggesting substantial Antarctic mass loss was initiated by warming of Southern Ocean waters, resulting from a weakening Atlantic meridional overturning circulation in response to North Atlantic surface freshening. Here, we report a blue-ice record of ice sheet and environmental change from the Weddell Sea Embayment at the periphery of the marine-based West Antarctic Ice Sheet (WAIS), which is underlain by major methane hydrate reserves. Constrained by a widespread volcanic horizon and supported by ancient microbial DNA analyses, we provide evidence for substantial mass loss across the Weddell Sea Embayment during the LIG, most likely driven by ocean warming and associated with destabilization of subglacial hydrates. Ice sheet modeling supports this interpretation and suggests that millennial-scale warming of the Southern Ocean could have triggered a multimeter rise in global sea levels. Our data indicate that Antarctica is highly vulnerable to projected increases in ocean temperatures and may drive ice-climate feedbacks that further amplify warming.
description: Isotope data (d18O and dD) from Patriot Hills blue ice, Ellsworth Mountains, Antarctica, as a proxy for West Antarctic ice mass loss during the Last Interglacial
DOI: 10.25921/es7s-2d97
title: NOAA/WDS Paleoclimatology - Indus Fan Miocene Plant Biomarker and Microfossil Data

description: In the late Miocene, grasslands spread across the forested floodplains of the Himalayan foreland, but the causes of the ecological transition are still debated. Recent seafloor drilling by the International Ocean Discovery Program (IODP) provides an opportunity to study the transition across a larger region as archived in the Indus submarine fan. We present a multiproxy study of past vegetation change based on analyses of the carbon isotopic composition (d13C) of bulk organic carbon, plant wax n-alkanes and n-alkanoic acids, and quantification of lignin phenols, charcoal, and pollen. We analyze the hydrogen isotopic composition (dD) of plant wax to reconstruct precipitation dD. We use the Branched and Isoprenoid Tetraether (BIT) index to diagnose shifts between terrestrial versus marine lipid inputs between turbidite and hemipelagic sediments. We reconstruct ocean temperatures using the TEX86 index only where marine lipids dominate. We find evidence for the late Miocene grassland expansion in both  facies, confirming this was a regional ecosystem transformation. Turbidites contain dominantly terrestrial matter from the Indus catchment (D-depleted plant wax), delivered via fluvial transport as shown by the presence of lignin. In contrast, hemipelagic sediments lack lignin and bear D-enriched plant wax consistent with wind-blown inputs from the Indian peninsula; these show a 7.4-7.2 Ma expansion of C4 grasslands on the Indian subcontinent. Within each facies, we find no clear change in dD values across the late Miocene C4 expansion, implying consistent distillation of rainfall by monsoon dynamics. Yet, a cooling in the Arabian Sea is coincident with the C4 expansion.
description: Biomarker and isotope data from sediments collected in the Indus Fan, core U1457, for 10-5 million years BP. LAST UPDATE 6/26/2024: Added IODP sample identification values to the data table. Provided Keywords: International Ocean Discovery Program; Expedition 355; Site U1457; biomarkers
DOI: 10.25921/eax7-a929
title: NOAA/WDS Paleoclimatology - Eastern Equatorial Pacific Mg/Ca and SST Data during the Pliocene

description: El Niño-Southern Oscillation (ENSO) is the strongest mode of interannual climate variability, and its predicted response to anthropogenic climate change remains unclear. Determining ENSO's sensitivity to climatic mean state and the strength of positive and negative feedbacks, notably the thermocline feedback, will help constrain its future behavior. To this end, we collected ENSO proxy data from the early and mid-Pliocene, a time during which tropical Pacific zonal and vertical temperature gradients were much lower than today. We found that El Niño events had a reduced amplitude throughout the early Pliocene, compared to the late Holocene. By the mid-Pliocene, El Niño amplitude was variable; sometimes reduced and sometimes similar to the late Holocene. This trend in Pliocene ENSO amplitude mirrors the long-term strengthening of zonal and vertical temperature gradients, and verifies model results showing dampened ENSO under reduced gradients due to a weaker thermocline feedback.
description: Trace metal data are from individual foraminifera. Ages estimated based on Mix et al 1995 age model.
 Provided Keywords: ENSO, paleoclimate, foraminifera, tropical Pacific, insolation
DOI: 10.25921/ee62-4w44
title: NOAA/WDS Paleoclimatology - Barclay - Copper River Delta Spruce A - TSME - ITRDB AK171

description: Fluctuations of four valley glaciers in coastal south-central Alaska are reconstructed for the past two millennia. Tree-ring crossdates on 216 glacially killed stumps and logs provide the primary age control, and are integrated with glacial stratigraphy, ages of living trees on extant landforms, and historic forefield photographs to constrain former ice margin positions. Sheridan Glacier shows four distinct phases of advance: in the 530s to c.640s in the First Millennium A.D., and the 1240s to 1280s, 1510s to 1700s, and c.1810s to 1860s during the Little Ice Age (LIA). The latter two LIA advances are also recorded on the forefields of nearby Scott, Sherman and Saddlebag glaciers. Comparison of the Sheridan record with other two-millennia long tree-ring constrained valley glacier histories from south-central Alaska and Switzerland shows the same four intervals of advance. These expansions were coeval with decreases in insolation, supporting solar irradiance as the primary pacemaker for centennial-scale fluctuations of mid-latitude valley glaciers prior to the 20th century. Volcanic aerosols, coupled atmospheric-oceanic systems, and local glacier-specific effects may be important to glacier fluctuations as supplemental forcing factors, for causing decadal-scale differences between regions, and as a climatic filter affecting the magnitude of advances.
description:  NOAA Template Chronology file added 2020-05-12.
DOI: 10.25921/ebj8-cf15
title: NOAA/WDS Paleoclimatology - Kringlemyr Bog, Norway 15.8-11.5ka Leaf Wax Fatty Acid d2H Data

description: The last deglaciation in northern Europe provides an opportunity to study the hydrologic component of abrupt climate shifts in a region with complex interactions between ice sheets and oceanic and atmospheric circulation. We use leaf wax hydrogen isotopes (δ2H) to reconstruct summer precipitation δ2H and aridity in southwestern Norway from 15.8 to 11.5 ka. We identify transitions to a more proximal moisture source before the ends of Heinrich Stadial 1 and the Younger Dryas, prior to local warming and increased primary productivity in both instances. We infer these changes in moisture delivery to southwestern Norway to be a response to northward shifts in the polar front caused by warm water intrusion into the North Atlantic, which preceded abrupt warming in the circum-North Atlantic. These results suggest that moisture transport pathways shift northward as warm surface ocean water reaches higher latitudes in the North Atlantic.
description: Leaf wax d2H data from lake sediments buried below a modern peat bog on the island of Karmoy, southwestern Norway
DOI: 10.25921/ez7j-4g49
title: NOAA/WDS Paleoclimatology - Sauchyn - Sweetgrass Hills - PIAL - ITRDB MT172

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 2020-01-15.
DOI: 10.25921/ecbk-r416
title: NOAA/WDS Paleoclimatology - Gut - Sihlwald-Streuboden - PCAB - ITRDB SWIT381

description: The pairwise statistical comparison of ring-width series is the basic analysis of dendro-provenancing studies. It is assumed that statistical proximity indicates similar provenance, but this assumption often remains untested. Especially for small areas with high topographic complexity, it is unknown to what extent statistical proximity and geographical provenance are correlated.

In this paper, dendro-provenancing is framed as a search for statistical Nearest Neighbors. The 'k-Nearest Neighbors leave one-out cross-validation' process (k-NN) is proposed as a method for validating dendro-provenancing approaches. Furthermore, it allows researchers to consistently compare and evaluate different proximity measures with respect to their suitability for dendro-provenancing. The validation process is demonstrated on a data set of 401 ring-width series of Norway spruce (Picea abies (L.) H. Karst.) encompassing 15 sites along elevational gradients in north-eastern Switzerland. Moreover, a new type of plot, the so-called scissor plot, is introduced to visualize the k-NN validation process.

Results indicate that dendro-provenancing depends heavily on differences in between sites high-frequency signal. Mean classification success for the relevant stages of the k-NN (CSRopen) ranged from 71.8% to 79.2% for the best performing measures. Classification errors occurred mainly between sites at elevations of 1000-1198 m a.s.l. At all other elevations and between different regions of the study area, only moderate differences in classification performance were detected. Thus, the results indicate that dendro-provenancing may be principally feasible even in a small region as studied here.
description: dendro-provenance study NOAA Template Raw Measurements file added 2020-03-09.
DOI: 10.25921/edyr-8404
title: NOAA/WDS Paleoclimatology - North American Lake Level Database

description: Sedimentary records of lake-level fluctuations have long provided unambiguous evidence of past hydrologic changes. Here, we synthesize geomorphic and sedimentological evidence of late-Quaternary lake-level changes across North America and show that currently moist regions were commonly drier than today. Many lakes across humid or snow-dominated areas of North America were lower than today or totally desiccated for prolonged periods but rose to their current levels following climate changes in recent millennia. Maps of 173 records show that hydroclimates responded to deglacial dynamics and orbital changes, but that regional hydrology changed even under the modest forcing and temperature variability of the past 8,000 years. Submerged paleoshorelines, ubiquitous across humid regions, reveal that North America's ecosystems and critical zone existed in a drier-than-modern state for much of the Quaternary and that continental moisture gradients often differed from today. The hydrologic changes underscore the climatic risk to many societally critical water supplies.
description: Liefert and Shuman North American Lake Level Database
DOI: 10.25921/e7rk-be86
title: NOAA/WDS Paleoclimatology - Maxwell - Little Concord Pond - TSCA - ITRDB ME045

description: Determining the response of forest growth and productivity to climate variability is crucial for understanding and modeling forest carbon sequestration in mesic temperate forests. Most tree-ring analyses have used monthly climate data. Daily climate data may be more appropriate to use in the determination of tree-ring response to climate because cell division, enlargement, and thickening occur during discrete periods of the growing season. We analyze annual tree-ring width and d13C from Tsuga canadensis (1992-2012) at ten sites in the northeastern US to test the null hypothesis that tree-ring width and d13C respond similarly to critical climate periods using daily climate data and linear regression. There was a significant difference in the climate response of ring width and d13C. Precipitation predicted both d13C and ring width with the highest r2 and greatest level of significance overall. d13C integrated climate over longer periods of the year (and previous year) than ring width at most sites. d13C showed a more consistent seasonal signal across sites for each climate variable than ring width. Our work provides a new perspective on the response of annual tree growth and d13C to climatic variability that can inform ecosystem productivity, carbon cycle, and earth system models.
description: Part of New England Hemlock Transect, 10 sites along a 500+ km transect stretching from CT to ME NOAA Template Raw Measurements file added 2021-02-22.
DOI: 10.15468/dl.rbxmpk
title: Occurrence Download

description: A dataset containing 137 species occurrences available in GBIF matching the query:
{
 "and" : [
 "TaxonKey is Johnsonella fausta",
 "HasCoordinate is true",
 "BasisOfRecord is one of (Observation, Machine Observation, Human Observation, Occurrence evidence)",
 {
 "not" : {
 "OccurrenceStatus" : [
 "is one of (Absent)"
 ]
 }
 }
 ]
}

 The dataset includes 137 records from 9 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0006420-251009101135966/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.