cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/ge4x-8027
title: NOAA/WDS Paleoclimatology - The Millennium Project: European Climate of the Last Millennium

description: Records of past temperature, precipitation, and other climate variables derived from paleoclimate proxies.  Parameter keywords describe what was measured in this data set.  Additional summary information can be found in the abstracts of papers listed in the data set citations.
description: The Millennium project is a multidisciplinary consortium of more than 38 partners from 16 European countries bringing together historians, chemists, physicists, biologists, geographers, climate modellers and geologists in a multi-disciplinary effort to reconstruct the climate of Europe over the last 1000 years using historical documents ranging from ships logs, church annals and harvest records, and natural archives such as tree rings, insect and plant remains from lakes and peat bogs, ice cores and sea shells. Reconstructing the climate of the past is important because it will allow us to say whether the changes observed over recent years are unusual when viewed within a longer term regional perspective.
DOI: 10.25921/gecm-hw96
title: NOAA/WDS Paleoclimatology - South China Sea ODP1146 AIM 24-25 Foraminiferal Stable Isotope Data

description: High-resolution planktic and benthic d18O records at Site 1146 (northern South China Sea) include structure within Marine Isotope Stage 5.4, 118.5-105.9 ka, that is not captured in stacked d18O records commonly used for age model construction and as proxies for global ice volume. Leveraging a common monsoonal influence, Site 1146 planktic d18O was aligned to speleothem d18O from southeastern China to derive a radiometrically calibrated (RC) age model. On the RC age model, the benthic d18O record contains structure equivalent in time to Antarctic Isotope Maximum (AIM) events 24 and 25. Sea level reconstructions for isotopic event 5.4 suggest that these benthic d18O events (AIM 24 and 25) derive from isotopic change (ice volume) although some temperature change cannot be completely excluded.
description: Foraminiferal stable isotope data (d18O and d13C) from core 
ODP1146 in the South China Sea for the interval 150 - 50 KYrBP. 
Antarctic Isotope Maximum (AIM) events 24 and 25 observed 
in the benthic marine record suggest changes in ice volume 
during Marine Isotope Stage (MIS) 5.4.  

Ocean Drilling Program Site 1146: 19°27'N, 116°16'E, 2092m depth
DOI: 10.25921/g5d4-qm24
title: NOAA/WDS Paleoclimatology - Eastern Subpolar North Atlantic Stable Isotope, Mg/Ca and SST Data During the Last Deglaciation

description: Millennial-scale climate fluctuations of the last deglaciation have been tied to abrupt changes in the Atlantic Meridional Overturning Circulation (MOC). A key to understanding mechanisms of MOC collapse and recovery is the documentation of upper ocean hydrographic changes in the vicinity of North Atlantic deep convection sites. Here we present new high-resolution ocean temperature and d18Osw records spanning the last deglaciation from an eastern subpolar North Atlantic site that lies along the flow path of the North Atlantic Current, approaching deep convection sites in the Labrador and Greenland-Iceland-Norwegian (GIN) Seas. High-resolution temperature and d18Osw records from subpolar Site 980 help track the movement of the subpolar/subtropical front associated with temperature and Atlantic MOC changes throughout the last deglaciation. Distinct d18Osw minima during Heinrich 1 (H1) and the Younger Dryas (YD) correspond with peaks in ice-rafted debris and periods of reduced Atlantic MOC, indicating the presence of melt water in this region that could have contributed to MOC reductions during these intervals. Increased tropical and subtropical d18Osw during these periods of apparent freshening in the subpolar North Atlantic suggest a buildup of salt at low latitudes that served as a negative feedback on reduced Atlantic MOC.
description: The chronology for ODP Site 980 is based on 35 monospecific foraminifera accelerator mass spectrometry (AMS) 14C dates(Globigerina bulloides, N. pachyderma (d), N. pachyderma (s)) spanning from the LGM to the late Holocene (Table 1 in publication). The Calib (Stuiver and Reimer, 1993) program (version 6.0, Marine09 calibration data set of Reimer et al., 2009) was used to convert 14C ages to calendar ages. The resulting age model suggests an average sedimentation rate of ~23 cm/ky throughout the deglacial interval. Calendar age differences between N. pachyderma (s) and N. pachyderma (d) at the same depths (Table 1) are mostly on the order of 100-200 years, except for a ~900-year difference just prior to the onset of the BA, which may reflect age differences in polar vs. subpolar water masses. These age discrepancies are taken into account by applying slightly different age models for N. pachyderma (s) vs. N. pachyderma (d) records (based on dual ages obtained at the four depth intervals listed in Table 1 in publication). Paired geochemical measurements of two planktonic foraminifer species, Neogloboquadrina pachyderma (dextral (d), or right-coiling) and N. pachyderma (sinistral (s), or left-coiling), constrain changes in upper ocean temperature and salinity and their relationship to global climate and deep ocean circulation. The oxygen isotope composition of foraminiferal calcite (d18Oc) reflects both ambient calcification temperature and seawater isotopic composition (d18Osw). Independent estimates of calcification temperature from Mg/Ca measurements differentiate temperature and d18Osw influences on d18Oc.
DOI: 10.25921/gb67-eh22
title: NOAA/WDS Paleoclimatology - Flower Valley Lake, Southeast Greenland 8800 Year Biogeochemical Data

description: Holocene paleoclimate records from Greenland help us understand the response of the Greenland Ice Sheet and regional oceanic and atmospheric circulation systems to natural climate variability in order to place recent changes in a longer-term perspective.  Here biogeochemical analysis of a lake sediment core from southeast Greenland is used to define changes in moisture balance and runoff during the Holocene in a catchment near the margin of the Greenland Ice Sheet.  A 1.6-m sediment core that spans the last 8.8 ka was recovered from Flower Valley Lake on Ammassalik Island.  Magnetic susceptibility, diatoms, bulk biogeochemical properties (TOC, C/N, d13Corg), and lipid biomarkers (n-alkanes; C16 -C31) reveal changes in clastic sedimentation and the relative input of terrestrial- and aquatic-derived organic matter.  Hydrogen isotope values (dD) of mid- (n-C25) and long-chain (n-C29, n-C31) n-alkanes allow reconstruction of dD of precipitation and summertime evaporation of lake water.  Following a period of early lake ontogeny and landscape stabilization after deglaciation from 8.4-7.0 ka, the mid-Holocene, 8.4-4.1 ka, is characterized by greater evaporative enrichment of the lake water as indicated by dD records. After 4.1 ka, there is a decrease in evaporative enrichment of the lake water.  There is also an abrupt transition to more variable sedimentation marked by sharp increases in magnetic susceptibility, C/N, d13Corg, and the concentration of long-chain n-alkanes, showing periodic delivery of terrestrial organic matter and clastic sediment to the lake.  Higher insolation during the mid-Holocene resulted in a warmer and drier climate with longer ice-free periods in the summer and enhanced evaporation of lake water.  The reduction in insolation and colder temperatures during the late Holocene caused a reduction in evaporation of lake water over the last 4.1 ka and was accompanied by periodic increases in surface runoff, which correspond with intervals of cold Greenland Ice Sheet surface temperatures.

description: Biogeochemical data from a 1.6-m sediment core from Flower Valley Lake on Ammassalik Island spanning the last 8.8 ka. Data include Magnetic susceptibility, bulk biogeochemical properties (TOC, C/N, d13Corg), lipid biomarkers (n-alkanes; C16 -C31), hydrogen isotope values (dD) of mid- (n-C25) and long-chain (n-C29, n-C31) n-alkanes.
DOI: 10.25921/gtk4-x327
title: NOAA/WDS Paleoclimatology - Florida Straits KNR166-2JPC51 9000 Year d18O, Mg/Ca SST, and d18Osw Data

description: Previous studies showed that sea surface salinity (SSS) in the Florida Straits as well as Florida Current transport covaried with changes in North Atlantic climate over the past two millennia. However, little is known about earlier Holocene hydrographic variability in the Florida Straits. Here, we combine Mg/Ca-paleothermometry and stable oxygen isotope measurements on the planktonic foraminifera Globigerinoides ruber (white variety) from Florida Straits sediment core KNR166-2 JPC 51 (24 deg 24.70'N, 83 deg 13.14'W, 198 m deep) to reconstruct a high-resolution (~25 yr/sample) early to mid Holocene record of sea surface temperature and d18OSW (a proxy for SSS) variability. After removing the influence of global d18OSW change due to continental ice volume variability, we find that early Holocene SSS enrichments are associated with increased evaporation/precipitation ratios in the Florida Straits during periods of reduced solar forcing, increased ice rafted debris in the North Atlantic and the development of more permanent El Niño-like conditions in the eastern equatorial Pacific. When considered with previous high-resolution reconstructions of Holocene tropical atmospheric circulation changes, our results provide evidence that variations in solar forcing over the early Holocene had a significant impact on the global tropical hydrologic cycle.
description: High resolution (~25 year) Holocene d18O, Mg/Ca-paleothermometry, and reconstructed d18OSW measurements on the planktonic foraminifera Globigerinoides ruber (white variety) from Florida Straits.
DOI: 10.25921/gvj2-3068
title: NOAA/WDS Paleoclimatology - Wiles - Pleasant Island - CHNO - ITRDB AK119

description: Yellow-cedar (Callitropsis nootkatensis (D. Don) Orsted ex D.P. Little) is in a century-long decline coinciding with the end of the Little Ice Age (LIA). The leading hypothesis explaining this decline is a decrease in insulating snowpack due to warming and increased susceptibility to damaging frosts in the root zone. A ring-width series from yellow-cedar on Excursion Ridge (260 m a.s.l.) in Glacier Bay National Park and Preserve, Alaska, and another from trees on Pleasant Island (150 m a.s.l.) in the Tongass National Forest in Icy Strait were compared with regional monthly temperature and precipitation data from Sitka, Alaska, to investigate the changing growth response to temperature at these sites. Comparisons with monthly temperatures from 1832 to 1876 during the end of the Little Ice Age show that the high-elevation Excursion Ridge and the low-elevation Pleasant Island sites strongly favored warmer January through July temperatures. Both tree populations have markedly changed their response from a positive to a strong negative correlation with January through July temperatures since 1950. This strong negative response to warming by the yellow-cedar together with a positive relationship with total March and April precipitation suggests that these yellow-cedar sites may be susceptible to decline. Furthermore, these analyses are consistent with the hypothesis that the yellow-cedar decline is linked to decreased snowpack.
description: NOAA Template Chronology file added 2018-12-20. NOAA Template Raw Measurements file added 2019-02-08.
DOI: 10.25921/gw83-dk77
title: NOAA/WDS Paleoclimatology - Agulhas Plateau 360KYr Stable Isotope Data

description: The rise in atmospheric CO2 concentrations observed at the end of glacial periods has, at least in part, been attributed to the upwelling of carbon-rich deep water in the Southern Ocean. The magnitude of outgassing of dissolved CO2, however, is influenced by the biological fixation of upwelled inorganic carbon and its transfer back to the deep sea as organic carbon. The efficiency of this biological pump is controlled by the extent of nutrient utilization, which can be stimulated by the delivery of iron by atmospheric dust particles. Changes in nutrient utilization should be reflected in the δ13C gradient between intermediate and deep waters. Here we use the δ13C values of intermediate- and bottom-dwelling foraminifera to reconstruct the carbon isotope gradient between thermocline and abyssal water in the subantarctic zone of the South Atlantic Ocean over the past 360,000 years. We find millennial-scale oscillations of the carbon isotope gradient that correspond to changes in dust flux and atmospheric CO2 concentrations as reported from Antarctic ice cores. We interpret this correlation as a relationship between the efficiency of the biological pump and fertilization by dust-borne iron. As the correlation is exponential, we suggest that the sensitivity of the biological pump to dust-borne iron fertilization may be increased when the background dust flux is low.
DOI: 10.25921/g40a-v954
title: NOAA/WDS Paleoclimatology - Touchan - Bear Canyon Middle - PISF - ITRDB NM585

description: Drought is a recurring phenomenon in the American Southwest. Since the frequency and severity of hydrologic droughts and other hydroclimatic events are of critical importance to the ecology and rapidly growing human population of this region, knowledge of long-term natural hydroclimatic variability is valuable for resource managers and policy-makers. An October-June precipitation reconstruction for the period AD 824-2007 was developed from multi-century tree-ring records of Pseudotsuga menziesii (Douglas-fir), Pinus strobiformis (Southwestern white pine) and Pinus ponderosa (Ponderosa pine) for the Jemez Mountains in Northern New Mexico. Calibration and verification statistics for the period 1896-2007 show a high level of skill, and account for a significant portion of the observed variance (>50%) irrespective of which period is used to develop or verify the regression model. Split-sample validation supports our use of a reconstruction model based on the full period of reliable observational data (1896-2007). A recent segment of the reconstruction (2000-2006) emerges as the driest 7-year period sensed by the trees in the entire record. That this period was only moderately dry in precipitation anomaly likely indicates accentuated stress from other factors, such as warmer temperatures. Correlation field maps of actual and reconstructed October-June total precipitation, sea surface temperatures and 500-mb geopotential heights show characteristics that are similar to those indicative of El Niño-Southern Oscillation patterns, particularly with regard to ocean and atmospheric conditions in the equatorial and north Pacific. Our 1184-year reconstruction of hydroclimatic variability provides long-term perspective on current and 20th century wet and dry events in Northern New Mexico, is useful to guide expectations of future variability, aids sustainable water management, provides scenarios for drought planning and as inputs for hydrologic models under a broader range of conditions than those provided by historical climate records.
description: NOAA Template Chronology file added 2018-12-20. NOAA Template Raw Measurements file added 2019-02-08.
DOI: 10.25921/g7vp-z612
title: NOAA/WDS Paleoclimatology - Frank - Torneträsk TR - PISY - ITRDB SWED332

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/gmmx-6878
title: NOAA/WDS Paleoclimatology - Bräker - Kirchberg - ABAL - ITRDB SWIT210

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/gmfz-eg50
title: NOAA/WDS Paleoclimatology - Mundo - Lago Rucachoroi - ARAR - ITRDB ARGE123

description: Seventeen tree-ring chronologies from the conifer Araucaria araucana (Molina) K. Koch have been analyzed across its range of distribution in Argentina. We studied the growth patterns and determined the main climatic factors influencing A. araucana radial growth. All the chronologies show a strong common signal observed by the high amount of variance explained by the first principal component (PC1) and the high mean correlation (r = 0.597) between the chronologies over the 1676-1974 interval. On this basis, we developed a regional chronology that is 866 years long (A.D. 1140-2006) and includes 621 tree-ring series. Based on the PC2 scores, chronologies were clearly separated by elevation in high- and low-elevation records. Regional tree growth is strongly negatively related to temperatures during summer and fall in the previous-growing season and spring in the current-growing season, respectively. A positive association of tree growth with precipitation is recorded during spring in the current growing season. These results suggest a close relationship between A. araucana tree growth and water availability on a regional scale. This observation is also consistent with a positive and significant correlation between our A. araucana regional record and a reconstruction of November-December rainfall for northern Patagonia inferred from the xeric Austrocedrus chilensis during the past 400 years. Negative correlations between A. araucana regional growth and the sea surface temperature in the Nino 3.4 region reflect the occurrence of above-mean summer temperatures in the region during positive tropical Pacific SST anomalies. The negative relationship with the Antarctic Oscillation (AAO) results from reduced precipitation in our study region during the positive phase of the AAO. The effect of elevation on water availability is consistent with significant correlations between ring-width variations at lower elevations and the Palmer Drought Severity Index during spring and summer in the current growing season. Our study emphasizes the high dendroclimatological potential of A. araucana chronologies for reconstructing past climate variations in northern Patagonia during the past millennium.
description: NOAA Template Raw Measurements file added 2019-04-29.
DOI: 10.25921/gnv2-jd56
title: NOAA/WDS Paleoclimatology - Luckman - Peyto Forefield and Num-ti-jah - PIAL - ITRDB CANA356

description: We present a network of thirteen annual ring-width chronologies from high elevation whitebark pine (Pinus albicaulis Engelm.) sites in the western Canadian Cordillera in order to assess the dendroclimatic potential of this long-lived tree species. The temperature signal within the chronologies is complex and strongly influenced by diverging trends in the summer temperature and ring-width records from across the region. A first differences transformation of the tree-ring and temperature records illustrates a loss of frequency coherence in growth response to summer temperatures following reduced radial growth in the 1950s. Prior to reduced growth, we note a positive association with summer temperatures for both first differenced (rd = 0.60) and traditional (r = 0.50) records. Following reduced growth, the association at first differences is maintained (rd = 0.49) whereas there is a change in the lower frequency component of tree growth response to summer temperatures (r = -0.34). We suggest the cause of this reduced temperature sensitivity is related to the interaction between diurnal temperature and cloud cover patterns, the hydrological regime of snowpack, and site conditions which have been amenable to the initiation of moisture stress during the latter half of the 20th century. Reduced radial growth is coincident with the arrival of white pine blister rust (Cronatium ribicola J.C. Fisch. ex Raben) into the study region which suggests this infestation may be related to the observed reduction in radial growth. Whitebark pine has considerable potential for the field of dendroclimatology. Unfortunately, the decline of the species due to the combined effects of climate change, white pine blister rust, mountain pine beetle (Dendroctonus ponderosae Hopk.), and forest fire exclusion practices indicate this potential may remain unfulfilled.
description: NOAA Template Raw Measurements file added 2019-02-04.
DOI: 10.25921/g7xd-7f72
title: NOAA/WDS Paleoclimatology - Krusic - Xinjiaing BLKB - LASI - ITRDB CHIN030

description: The Asian monsoon system affects more than half of humanity worldwide, yet the dynamical processes that govern its complex spatiotemporal variability are not sufficiently understood to model and predict its behavior, due in part to inadequate long-term climate observations. Here we present the Monsoon Asia Drought Atlas (MADA), a seasonally resolved gridded spatial reconstruction of Asian monsoon drought and pluvials over the past millennium, derived from a network of tree-ring chronologies. MADA provides the spatiotemporal details of known historic monsoon failures and reveals the occurrence, severity, and fingerprint of previously unknown monsoon megadroughts and their close linkages to large-scale patterns of tropical Indo-Pacific sea surface temperatures. MADA thus provides a long-term context for recent monsoon variability that is critically needed for climate modeling, prediction, and attribution.
description: Purpose of Collection:  
# Climatology - precipitation analysis NOAA Template Raw Measurements file added 2019-04-08.