cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25921/vq9a-s483
title: NOAA/WDS Paleoclimatology - Tumajer - U Houkvice - QURO - ITRDB CZEC028

description: Drought events and the overuse of groundwater for water supply can cause significant declines of groundwater levels in naturally poorly drained forest stands. However, the documented growth reactions of trees to declines in groundwater level vary a lot and range from positive because of increased soil aeration to strongly negative because of drought stress. We analysed changes in tree-ring width and earlywood average vessel lumen area of Quercus robur from sites above an artesian aquifer, whose groundwater level declined in the late 1980s by about 5 m due to water pumping. Because we expected different responses of individual trees due to local microtopography and fine root distribution, we performed both site-level and tree-level analyses. Our results show that the site-level response of tree growth to groundwater-level pumping was not uniform. Individual trees were clustered into groups of drought-limited and water abundance-limited individuals. The response of trees to groundwater pumping differed between clusters - drought-sensitive trees responded negatively, whereas the growth of trees limited by water abundance remained stable or slightly increased. Inter-series correlation of drought-limited trees significantly increased in the period with the lowest groundwater level. In contrast to tree-ring widths, earlywood vessel lumen area series contained common temperature signal, with no imprint of groundwater-level alteration. Our results indicate that poorly drained forest ecosystems are characterized by a significantly individualistic response of radial growth to groundwater-level alteration. These individualistic responses could be, however, overshadowed in stand-level average tree-ring width chronologies.
description: The data represent raw tree-ring width series. One core was extracted from each tree (Quercus robur). NOAA Template Raw Measurements file added 2021-12-29.
DOI: 10.25921/v3bz-w365
title: NOAA/WDS Paleoclimatology - Thapa - Dandakharka - PIWA - ITRDB NEPA056

description: Pine forests provide goods and services crucial to more than ten million people living in the middle-mountains (600-4000m) of Nepal. These critically important forests are already often overexploited and could be at risk from future climate change. In order to investigate the combined effects of climate and human disturbances on the growth of pine forests, we established a new network of tree-ring sites in six Pinus wallichiana and four P. roxburghii forests across the dry inner valleys of eastern Nepal's Koshi River watershed. We produced measurements of total annual ring widths, and detrended individual tree-ring series with 67% cubic splines to produce site-level chronologies. The Koshi tree-ring chronologies were compared against local records of mean monthly temperature and total monthly rainfall to identify the main climatic factor(s) limiting pine growth. We also employed a relative growth change method to estimate growth releases and suppressions in ring-width series as indicators of disturbances. At all sites, trees are relatively young (median age was 102 years) and variations in ring-width provide estimates of tree growth over only the past century. Ring-width chronologies from the Koshi have a weak common signal strength in comparison to trees from the same species obtained from sites in the central Himalaya, and the climate-growth response of Koshi pines appears to be governed primarily by moisture balance during winter. Disturbance events evident in pine ring-width data are largely asynchronous, which suggests these forest have been historically perturbed by human influences rather than large-scale climatic or ecological influences. The sacred forest at Sikri contained the oldest living trees (118 years), had the lowest number of disturbance events, and preserved a stronger common signal, which provided additional evidence of the effects of humans on other pine forests in the Koshi basin. Based on our findings, we suggest that modeling the future growth and distribution of pine trees in eastern Nepal should consider winter moisture. Furthermore, management strategies to better conserve pine forests in eastern Nepal should incorporate the two competing influences of climate and human activities on tree growth.
description: Koshi River basin, Nepal NOAA Template Raw Measurements file added 2020-11-18.
DOI: 10.25921/vd3f-ya86
title: NOAA/WDS Paleoclimatology - Christensen - Sinking Creek - New Zion Road - PLOC - ITRDB VA044

description: Trees, mostly sycamore (Platanus occidentalis L.), are growing in the channel of the lower 7 km of Sinking Creek in the Appalachian Mountains of Virginia. Sinking Creek is a gravel-bedded stream that disappears into a subsurface cave network and for its lower 7 km, flows intermittently throughout the year, exposing a dry streambed. We hypothesize that there have been low-flow periods in the past conducive to tree-seedling establishment. We describe this system and test our hypothesis through an analysis of hydrologic, dendrochronological, and geomorphic data to better understand the conditions leading to tree establishment and persistence in the stream channel. To our knowledge, this is the first study on trees growing in the channel of an intermittent stream in a temperate environment. Most riparian vegetation studies along intermittent rivers and ephemeral streams focus on dryland areas, where trees have also been observed growing in the channel. Our results show that sycamores are the oldest trees in the channel, that they established during periods of low precipitation, and they are located at the upstream end of bars. In their wake, on bars, other younger trees have established. Analysis of tree roots suggest that scour of the base of some trees occurred during thalweg migration. Additionally, we present a conceptual model of the flow-tree-sediment dynamics occurring in Sinking Creek that can be further tested as part of future work. This work highlights the conditions for tree establishment in streams, which is an important threshold for any streams under projected future drying.
description: These cores were collected from an area where Sinking Creek sinks below the ground surface. NOAA Template Raw Measurements file added 2021-12-29.
DOI: 10.25921/vmbb-4r02
title: NOAA/WDS Paleoclimatology - Maxwell - Meltzer Woods - QUMA - ITRDB IN023

description: Tree-ring reconstructions of streamflow can provide long-term perspectives of flow variability that may be useful in management strategies for water resources. Relative to other portions of the United States, there is a dearth of tree-ring based streamflow reconstructions in the Midwest. The Wabash River is an important water resource in Indiana and Illinois where many sectors rely on it. Here, to better understand the historic hydroclimate within the Wabash River Basin, we reconstructed June-September streamflow for a tributary of the Wabash River using three statistical approaches: the traditional basin approach, and the recently-developed climate-footprint, and drought-reconstruction approaches. Our reconstructions explained 53-71% of the variance for the common period (1941-1984). We find that in our three reconstructions, there are extreme droughts and pluvials that exceed those during the instrumental period, including a sustained five-decade low-flow event in the early 19th century. Overall, we find that the traditional basin approach produced the most robust model but had the shortest reconstruction length of the three approaches, as it requires the predictor chronologies to be derived from within the basin. Our results indicate that there are merits and drawbacks to each approach with the general pattern of sacrificing variance explained for reconstruction length.
description: Streamflow, Eastern Deciduous Forest NOAA Template Raw Measurements file added 2020-09-03.
DOI: 10.25921/vpz8-e450
title: NOAA/WDS Paleoclimatology - South China Sea d18O and hurricane data from 1568 to 1965 CE

description: We used the top age of storm-relocated coral blocks (SRCBs) from Xisha Islands and Huangyan Island, South China Sea (SCS), Northwestern Pacific region (NWP), in combination with existing paleotempestology records and instrumental climatic data, to reconstruct the spatio-temporal changes in tropical cyclone (TC) activity over the past millennium, and to project its future trends in the NWP. We found a positive correlation between the frequencies of TCs, typhoons, and super-typhoons and the NINO3.4 on the interannual timescale during 1945-2019. TCs latitude has a significant positive correlation with SST, with a northward migration rate of 80 ± 11 km per decade, equivalent to a northward migration rate of 606 ± 82 km per 1ºC increase during 1951-2019. Coral d18O can well indicate the month of paleo-TCs occurrence. The frequency of SRCBs (and by inference, TCs) is relatively low during relatively warm periods (RWP) but high during relatively cold periods (RCP) in the SCS. The spatio-temporal pattern inferred from paleotempestology records further supports the notion of North-South migration in TC activity as revealed by the instrumental record in this study. TC activity mainly affected relatively low latitudes (e.g., Philippines, Vietnam, and Hainan, Guangdong, Taiwan) during the RCP (AD 1450-1900), but it migrated from low latitudes towards higher latitudes during the RWP (AD 1000-1450), affecting locations such as Zhejiang, Jiangsu, and Shandong, southwestern Japan, the Korean Peninsula, and even Northeast China. Fujian and northern Guangdong may be in a transition zone of paleo-TC activity between the North and the South in the past millennium. As global warming continues, the mean tracks and landfall locations of TCs will continue to migrate northward in this region.
description: Beijiao Reef (BJ): 17.0837, 111.5329, ~0 m; Chenghang Island (CH): 16.4471, 111.7067, ~0 m; Huangyan Island (HYD): 15.1045, 117.8015, ~0 m; Lingyang Reef (LYJ): 16.4761, 111.5730, ~0 m; Ganquan Island (GQ): 16.5048, 111.5876, ~0 m. Provided Keywords: Tropical Cyclones, Poleward Shift, Past millennium, Coral d18O, Coral blocks, Northwest Pacific
DOI: 10.25921/vwsx-zq56
title: NOAA/WDS Paleoclimatology - Dye - Dukes Research Natural Area - TSCA - ITRDB MI023

description: Availability of high-quality primary ecological datasets like tree-ring growth is critical to the progress of ecological sciences. The International Tree-Ring Databank (ITRDB) is the premier public archive for interannual records of tree-ring growth (i.e., “chronologies”); however, there is currently a dearth of available chronologies that extend into the 21st century. In Michigan, none of the available records for eastern hemlock extends past 1983. Unfortunately, this reduces the availability of these chronologies for study of recent ecological and climatological change or for their integration with new environmental measuring technologies. In this paper, we fill part of this gap for northern Michigan and examine how our datasets can inform long-term studies of ecology-climate interactions in the Midwest region. We present multi-century Tsuga canadensis (L.) Carrière (eastern hemlock) tree-ring growth records for four sites in the Upper Peninsula of Michigan, U.S.A., covering the periods 1708–2015, 1754–2015, 1794–2015, and 1857–1995. We explore potential applications of these datasets by examining basic correlations between interannual growth on the one hand and regional temperature and Palmer Drought Severity Index (PDSI, an estimate of dryness) values on the other. At all four sites, growth is negatively correlated with previous summer and current spring temperature, while growth is positively correlated with previous summer PDSI at three of the four sites.
description: Upper Peninsula TSCA NOAA Template Raw Measurements file added 2021-02-22.
DOI: 10.25921/vtcx-7987
title: NOAA/WDS Paleoclimatology - Treml - Polom - PCAB - ITRDB CZEC019

description: Extreme tree growth reductions represent events of abrupt forest productivity decline and carbon sequestration reduction. An increase in their magnitude can represent an early warning signal of impending tree mortality. Yet the long-term trends in extreme growth reductions remain largely unknown. We analyzed the trends in the proportion of trees exhibiting extreme growth reductions in two Central-European conifer species - Pinus sylvestris (PISY) and Picea abies (PCAB) - between 1901 and 2018. We used a novel approach for extreme growth reduction quantification by relating their size to their mean recurrence interval. Twenty-eight sites throughout Czechia and Slovakia with 1120 ring width series representing high- and low-elevation forests were inspected for extreme growth reductions with recurrence intervals of 15 and 50 years along with their link to climatic drivers. Our results show the greatest growth reductions at low-elevation PCAB sites, indicating high vulnerability of PCAB to drought. The proportions of trees exhibiting extreme growth reductions increased over time at low-elevation PCAB, decreased recently following an abrupt increase in the 1970-1980s at high-elevation PCAB, and showed nonsignificant trends in high- and low-elevation PISY. Climatic drivers of extreme growth reductions, however, shifted over time for all site categories as the proportion of low-temperature-induced extreme growth reductions declined since the 1990s, whereas events caused by drought consistently increased in frequency during the same period. We observed higher growth volatility at the lower range of distribution compared with the upper range margin of PISY and PCAB. This will undoubtedly considerably impact tree growth and vitality as temperatures and incidence of drought in Central Europe are expected to further increase with ongoing climate change.
description: Extreme growth reductions in Central-European Pinus sylvestris (PISY) and Picea abies (PCAB). NOAA Template Raw Measurements file added 2021-12-29.
DOI: 10.25921/vrrp-yj58
title: NOAA/WDS Paleoclimatology - Esper - Hallgarter Zange - PISY - ITRDB GERM232

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: Missing rings were inserted with the value 1. NOAA Template Raw Measurements file added 2020-09-03.
DOI: 10.25921/vk18-ty67
title: NOAA/WDS Paleoclimatology - Topptjonna, Norway Surface Temperature Reconstructions from 6,000 to 12,000 Years Ago

description: By using heavy coring equipment in two high-altitudinal lakes (1253 and 1316 m a.s.l.) at Dovre, Central Norway, 1–1.5 m of unsorted coarsely minerogenic sediments were retrieved below the Holocene organic sediments. The minerogenic sequence contained well-preserved pollen and chironomid remains, revealing new and detailed palaeoenvironmental knowledge of the mountains in Central Norway during the last 5–6000 years of the Lateglacial (LG) period. However, the LG chronology is based on biostratigraphical correlations and not on 14C-dates, due to low organic content in the minerogenic sediments. The emerging LG nunataks, probably indicating a thin and multi-domed Scandinavian ice-sheet, was rapidly inhabited by immigrating species which could explain the present centric distributions of certain arctic-alpine plants. The LG vegetation development included a pre-interstadial dominated by mineral-soil pioneers, an interstadial dominated by shrubs and dwarf-shrubs, and the Younger Dryas cold period with recurring dominance of pioneers. Pollen and stomata of Pinus and Picea indicate their local LG presence at Dovre. LG climate oscillations are indicated by pollen stratigraphy and for the later part of LG also by chironomids. These oscillations could correspond to Heinrich event 1, GI-1d, GI-1b, and the Younger Dryas cold events. The LG interstadial reached July mean temperatures of more than 7–8 °C, similar to the present. Chironomids colonized the lake already during the onset of the interstadial, albeit at very low richness and abundances. Starting from YD, there are sufficient chironomid head capsules to perform a temperature reconstruction. The Holocene warming of about 2 °C initiated a vegetation closure from snow beds and dwarf-shrub tundra to shrubs and forests. Birch-forests established about 10 ka cal BP, slightly earlier than pine forests. Alnus expanded ca 9.2 ka cal BP and a thinning of the local forests occurred from ca 7 ka cal BP. Two short-lasting climate deteriorations found in the pollen record and the chironomid record may represent the Preboreal Oscillation and the 8.2 event. The Holocene Thermal Maximum is indicated around ca 7.8–7.3 ka cal BP showing a chironomid-inferred July mean of at least 11 °C. This is ca 3 °C warmer than today.
description: This dataset was contributed as part of the Temperature-12k project (https://doi.org/10.25921/4RY2-G808). Data were contributed to the project from the original data generators, who are listed in the Investigator field of this template file. Additional notes regarding the use of these data in the Temperature-12k project can be found in the LiPD file listed as an Online_Resource of this template file.
DOI: 10.25921/vdw7-w626
title: NOAA/WDS Paleoclimatology - Atlantic Meridional Overturning Circulation (AMOC) Reconstruction from 10,000 to 2,000 BP

description: Based on new and published cosmic-ray exposure chronologies, we show that glacier extent in the tropical Andes and the north Atlantic regions (TANAR) varied in-phase on millennial timescales during the Holocene, distinct from other regions. Glaciers experienced an early Holocene maximum extent, followed by a strong mid-Holocene retreat and a re-advance in the late Holocene. We further explore the potential forcing of TANAR glacier variations using transient climate simulations. Since the Atlantic Meridional Overturning Circulation (AMOC) evolution is poorly represented in these transient simulations, we develop a semi-empirical model to estimate the “AMOC-corrected” temperature and precipitation footprint at regional scales. We show that variations in the AMOC strength during the Holocene are consistent with the observed glacier changes. Our findings highlight the need to better constrain past AMOC behavior, as it may be an important driver of TANAR glacier variations during the Holocene, superimposed on other forcing mechanisms.
description: This AMOC reconstruction is based on the Ayache et al. (2018) reconstruction of the AMOC. This reconstruction was based on 22 proxy records of SST in the North Atlantic. The reconstruction was obtained from a Principal Component Analysis of those 22 proxy records. The reconstruction of the AMOC has been tested and validated using pseudo-proxy approach, consisting in testing the performance of the statistical method to reconstruct the AMOC from model simulations using the location of available proxy data. The AMOC reconstruction was also compared with other independent proxy records of the deep ocean circulation and show consistency. The reconstruction has a time resolution of 50 years and cover the period -10-2kY.
For further details on the reconstruction method, see: Ayache M. Swingedouw D., Mary Y., Eynaud F., Colin C. (2018) AMOC variability over the Holocene: A new reconstruction based on multiple proxy-based SST records. Global and Planetary Changes 170, pp. 172-189. 
This first reconstruction from the latter paper was not calibrated in terms of Sverdrups of variation of the AMOC but standardised on the available period. To circumvent this issue, the reconstruction proposed here has been calibrated using Northern Hemisphere reconstruction of Kaufman et al. (2020) and transient model simulations as well as hosing simulations, in order to quantify the climatic impacts of AMOC variations.
DOI: 10.25921/vxax-w749
title: NOAA/WDS Paleoclimatology - Dasuopu, China 210 Year Ice Core Refractory Black Carbon Data

description: Records of past temperature, precipitation, atmospheric trace gases, and other aspects of climate and environment derived from ice cores drilled on glaciers and ice caps around the world.  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: Ice core refractory black carbon data at sub-annual resolution from Dasuopu Glacier, Mt. Xixiabangma, China for 1781-1992 CE.
DOI: 10.25921/vmvs-ct55
title: NOAA/WDS Paleoclimatology - Vanoni - Andeer - PCAB - ITRDB SWIT400

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: Reference: 
# Vanoni M. 2012. Klimatische Einflusse auf die Wachstumsvariabilitat von Weisstanne und Fichte entlang des Weisstannen-Ausbreitungsgradienten. Master thesis. ETH Zurich, Zurich. NOAA Template Raw Measurements file added 2021-05-03.
DOI: 10.25921/v2hk-2c67
title: NOAA/WDS Paleoclimatology - Kanaan Cave, Lebanon MIS 6 Stable Isotope Data

description: Little is known about terrestrial climate dynamics in the Levant during the penultimate interglacial-glacial period. To decipher the palaeoclimatic history of the Marine Oxygen Isotope Stage (MIS) 6 glacial period, a well-dated stalagmite (~194 to ~154 ka) from Kanaan Cave on the Mediterranean coast in Lebanon was analyzed for its petrography, growth history, and stable isotope geochemistry. A resolved climate record has been recovered from this precisely U-Th dated speleothem, spanning the late MIS 7 and early MIS 6 at low resolution and the mid-MIS 6 at higher resolution. The stalagmite grew discontinuously from ~194 to ~163 ka. More consistent growth and higher growth rates between ~163 and ~154 ka are most probably linked to increased water recharge and thus more humid conditions. More distinct layering in the upper part of the speleothem suggests strong seasonality from ~163 ka to ~154 ka. Short-term oxygen and carbon isotope excursions were found between ~155 and ~163 ka. The inferred Kanaan Cave humid intervals during the mid-MIS 6 follow variations of pollen records in the Mediterranean basins and correlate well with the synthetic Greenland record and East Asian summer monsoon interstadial periods, indicating short warm/wet periods similar to the Dansgaard-Oeschger events during MIS 4-3 in the eastern Mediterranean region.
description: Stable isotope (d13C and d18O) data from a stalagmite collected in Kanaan Cave, Lebanon, for Marine Isotope Stage 6 (193-154 ka)