311 results
Search Results
2. Dendroclimatology in Latin America: A Review of the State of the Art.
- Author
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Sánchez-Calderón, Oscar David, Carlón-Allende, Teodoro, Mendoza, Manuel E., and Villanueva-Díaz, José
- Subjects
DENDROCLIMATOLOGY ,TROPICAL dry forests ,CLIMATE change ,DENDROCHRONOLOGY ,TEMPERATE climate ,TROPICAL forests - Abstract
The application of dendrochronology for understanding climatic variations has been of great interest to climatologists, ecologists, geographers, archeologists, among other sciences, particularly in recent decades when more dendrochronological studies have been developed. We analyzed and identified the current state and recent advances in dendroclimatology in Latin America for the period 1990 to 2020. We carried out reviews in ScienceDirect, Web of Science, and Scopus databases with the keywords "dendrochronology", "dendroclimatology", "dendrochronology and climatic variability", "dendroclimatology and climatic variability", "dendrochronology and trend", and "dendroclimatology and trend" for each Latin American country. Results show that dendroclimatological research in the last 11 years has increased and has been mainly developed in temperate climate zones (83%) and tropical or subtropical areas (17%), where conifer species have been the most used with over 59% of the studies. However, broadleaf species for dendrochronological studies have also increased in the last decade. Dendroclimatological research in Latin America has provided important advances in the study of climatic variability by defining the response functions of tree-rings to climate and developing climatic reconstructions. Our research identified areas where it is necessary to increase dendroclimatic studies (e.g., dry and tropical forests), in addition to applying new techniques such as isotope analysis, blue intensity, dendrochemistry, among other tree-ring applications. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
3. How different sources of climate databases influence assessment of growth response in dendroclimatic analyses – case study from Lapland.
- Author
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Sitko, R., Vido, J., Škvarenina, J., Pichler, V., Scheer, L., Škvareninová, J., and Nalevanková, P.
- Subjects
DENDROCLIMATOLOGY ,TIME series analysis ,METEOROLOGICAL precipitation - Abstract
The paper deals with the comparison of the time series from different climate databases. We compared the measured data with the modelled data of monthly and seasonal temperature means and precipitation totals. Reliable and as long as possible time series of such data represent the basic starting point of dendroclimatic analyses. We evaluated the differences in the growth response of spruce derived using different databases of the stated climatic characteristics. The stem cores used to derive the cross-correlation function were taken from Hårås locality situated in the boreal zone of the Swedish part of Lapland. We compared the measured records from the nearest me10 teorological stations situated 18 and 40 km away from the locality with the interpolated values from CRU TS 3.21 climate database and with the reconstructed 502-year-long database. The spatial resolution of the modelled databases was 0.5° × 0.5° of latitude and longitude. We found a systematic error of different magnitudes in the modelled values, and we also quantified a random error and the overall accuracy of the data. The temperature model underestimated the data in comparison with the measured values, while the precipitation model overestimated the data. We also found that the radial increments of spruce correlated more strongly with the temperature than with the precipitation. Hence, in the conditions of the boreal zone, temperature is a more important factor affecting tree-ring formation. We found significantly higher correlations between the radial increment and the modelled precipitation data than with the data measured at the precipitation station situated 18km from the locality of interest. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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4. I-BIND: International Blue intensity network development working group
- Author
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Ryszard J. Kaczka and Rob Wilson
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Ecology ,Best practice ,Political science ,Short paper ,Dendrochronology ,Regional science ,Plant Science ,Dendroclimatology ,Method development - Abstract
Blue Intensity (BI) is coming of age in dendrochronology, although some methodological challenges are still left to be solved. In the last 20 years, 59 papers have been published focussing mainly on climatological based studies, although BI has also been shown to be useful both for historical dating and dendroecological studies. This short paper briefly reviews the BI method development of the last two decades and introduces a new collaborative initiative called I-BIND (International Blue Intensity Network Development Working Group), which is supported by the Association of Tree-Ring Research. The main aims of I-BIND are to promote continued methodological development, communicate best practice via workshops, encourage the development of BI data networks to enhance both dendroclimatology and dendro-historical dating, and to create a rich environment in which innovative and novel initiatives can be explored and discussed.
- Published
- 2021
5. Are there enormous age-trends in stable carbon isotope ratios of oak tree rings?
- Author
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Darren Davies, Christopher Bronk Ramsey, Danny McCarroll, Josie E. Duffy, Neil J. Loader, Daniel Miles, and Giles H.F. Young
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Archeology ,Global and Planetary Change ,010504 meteorology & atmospheric sciences ,Ecology ,dendrochronology ,Paleontology ,Dendroclimatology ,010502 geochemistry & geophysics ,01 natural sciences ,Research Papers ,palaeoclimate ,Tree (data structure) ,Quercus ,13. Climate action ,Isotopes of carbon ,Dendrochronology ,Environmental science ,Physical geography ,dendroclimatology ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
We test a recent prediction that stable carbon isotope ratios from UK oaks will display age-trends of more than 4‰ per century by measuring >5400 carbon isotope ratios from the late-wood alpha-cellulose of individual rings from 18 modern oak trees and 50 building timbers spanning the 9th–21st centuries. After a very short (c.5 years) juvenile phase with slightly elevated values, the number of series that show rising and falling trends is almost equal (33:35) and the average trend is almost zero. These results are based upon measuring and averaging the trends in individual time-series; the ‘mean of the slopes’ approach. We demonstrate that the more conventional ‘slope of the mean’ approach can produce strong but spurious ‘age-trends’ even when the constituent series are flat, with zero slope and zero variance. We conclude that it is safe to compile stable carbon isotope chronologies from UK oaks without de-trending. The isotope chronologies produced in this way are not subject to the ‘segment length curse’, which applies to growth measurements, such as ring width or density, and have the potential to retain very long-term climate signals.
- Published
- 2020
6. Distribution of Mechanical Properties in Annual Growth Rings of Deciduous Trees Measured Using Scanning Nanoindentation.
- Author
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Golovin, Yu. I., Tyurin, A. I., Gusev, A. A., Matveev, S. M., Golovin, D. Yu., and Vasyukova, I. A.
- Subjects
- *
YOUNG'S modulus , *DENDROCHRONOLOGY , *ENGLISH oak , *WOOD , *DENDROCLIMATOLOGY - Abstract
Abstract—The paper presents the results of mechanical properties scanning by means of nanoindentation across the annual growth rings of deciduous trees wood, small-leaved lime (Tilia cordata) and common oak (Quercus robur) in particular. Significant variations in microhardness H and Young's modulus E radial dependencies have been found for any of the studied species. Results can be useful (1) to amend the understanding the nature of macromechanical properties of various wood species and to reveal the details of their formation depending upon microstructural characteristics, (2) to optimize the technologies of growing, reinforcement and subsequent usage of the wood, (3) to develop new independent methods in dendrochronology and dendroclimatology. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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7. The Holocene of Sweden – a review.
- Author
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Wastegård, Stefan
- Subjects
HOLOCENE Epoch ,LITTLE Ice Age ,PLEISTOCENE-Holocene boundary ,CLIMATE research ,TRANSFER functions - Abstract
This paper presents a review on more than hundred years of palaeoenvironmental research in Sweden; from early descriptions of peat and tufa deposits in the late nineteenth and early twentieth centuries to multiproxy transfer function studies in the late twentieth and early twenty-first centuries CE. Research on Holocene climate variability has a long history in Sweden and many ideas and concepts about changes in temperature and precipitation during the Holocene originated in Fennoscandia. The Holocene climate evolution in Sweden follows a pattern in common for many northern latitude records with a rapid warming starting at the Pleistocene–Holocene boundary at c. 11 650 cal a BP, followed by the middle Holocene thermal maximum between c. 8000 and 5000 cal a BP. A change to colder and wetter conditions starts c. 4000 cal a BP and lasts until the late 1800 s CE. There is evidence for climatic anomalies such as the 8.2 and 4.2 ka BP events and the Little Ice Age (LIA) but only inconclusive evidence for other events, such as the 10.3 ka BP event. The main pattern of Holocene climate and environmental evolution is well known for most parts of Sweden, but the present review also shows that several research questions remain to be addressed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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8. Indication of Environmental Changes in Mountain Catchments by Dendroclimatology.
- Author
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VRTIŠKA, JIŘÍ, KŘEČEK, JOSEF, and TOGNETTI, ROBERTO
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DENDROCLIMATOLOGY ,GLOBAL environmental change ,WATERSHEDS ,ATMOSPHERIC deposition ,WOOD anatomy - Abstract
In the Czech Republic, mountain watersheds are mostly forested with dominant Norway spruce (Picea abies) plantations. The aim of this paper is to analyse changes in radial growth and xylem anatomy of Norway spruce trees in the upper plain of the Jizera Mountains, related to changes in climate (air temperature, precipitation), air pollution and acid atmospheric deposition. Data of two neighbouring climate stations were used to detect trends in air temperatures and precipitation. At elevations of 745-1060 m a.s.l., the ring-width growth was significantly affected by mean annual temperature, while impacts of elevation and precipitation were not significant. In the period 1975-1995, the detected drop in tree radial growth (ca 60% of the normal period, prior to the peak of acid atmospheric deposition) corresponded to the increase in atmospheric SO
2 concentrations and acid atmospheric deposition. The number of cells in tree rings decreased by ca 30-40% in comparison with the normal period, but the mean size of cells did not change significantly. In the last 20 years, increasing radial growth has been detected simultaneously with rising air temperature, and density of cells decreased by 30% in early wood, and by 10% in late wood, increasing the total number of cells in tree rings by ca 10% in comparison with the normal period. Integrated effects of climate and non-climate variables on the variation of tree radial growth in the Jizera Mountains reflected the legacy of acid atmospheric deposition in the forest ecosystem. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
9. Multiscale wood micromechanics and size effects study via nanoindentation.
- Author
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Golovin, Yuri I., Gusev, Alexander A., Golovin, Dmitry Yu., Matveev, Sergey M., Tyrin, Alexander I., Samodurov, Alexander A., Korenkov, Viktor V., Vasyukova, Inna A., and Yunack, Maria A.
- Subjects
WOOD ,MICROMECHANICS ,NANOINDENTATION ,DENDROCLIMATOLOGY ,DENDROCHRONOLOGY - Abstract
Wood as a material is a natural composite with a complex hierarchically arranged structure. All scale levels of wood structure contribute to its macroscopic mechanical properties. The nature of such characteristics and deformation modes differs radically at different scale levels. Wood macroscopic properties are well studied, and the relevant information can be easily found in the literature. However, the knowledge of the deformation mechanisms at the mesoscopic level corresponding to the cellular structure of early and late wood layers of annual growth rings is insufficient. It hinders building the comprehensive multiscale model of how wood mechanical properties are formed. This paper described the results of scanning of mechanical properties of softwood and hardwood samples, such as common pine, small-leaf lime, and pedunculate oak, by means of nanoindentation (NI). The NI technique allows varying the size of deformed region within a wide range by altering maximal load (P
max ) applied to the indenter so that one can repeatedly and non-destructively test wood structural components at different scale levels on the same sample without changing the technique or equipment. It was discovered that the effective microhardness (Heff ) and Young's modulus (Eeff ) decreased manifold with Pmax growing from 0.2 to 2 000 mN. This drop in Heff was observed when the locally deformed region grew, and resulting from Pmax increase generally follows the rule similar to the Hall-Petch relation for yield stress, strength, and hardness initially established for metals and alloys, though obviously in those cases the underlying internal mechanisms are quite different. The nature and micromechanisms of such size effect (SE) in wood revealed using NI were discussed in this study. At Pmax < 0.2 mN, the deformed area under the pyramidal Berckovich indenter was much smaller than the cell wall width. Hence, in this case, NI measured the internal mechanical properties of the cell wall material as long as free boundaries impact could be neglected. At Pmax > 200 mN, the indentation encompassed several cells. The measured mechanical properties were significantly affected by bending deformation and buckling collapse of cell walls, reducing Heff and Eeff substantially. At Pmax ≈ 1-100 mN, an indenter interacted with different elements of the cell structure and capillary network, resulting in intermediate values of Heff and Eeff . Abrupt changes in Heff and Eeff at annual growth ring boundaries allow accurate measuring of rings width, while smoother and less pronounced changes within the rings allow identification of earlywood and latewood layers as well as any finer changes during vegetation season. The values of ring width measured using NI and standard optical method coincide with 2% - 3% accuracy. The approaches and results presented in this study could improve the understanding of nature and mechanisms lying behind the micromechanical properties of wood, help to optimize the technologies of wood farming, subsequent reinforcement, and utilization, as well as to develop new highly informative techniques in dendrochronology and dendroclimatology. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
10. From Intra-plant to Regional Scale: June Temperatures and Regional Climates Directly and Indirectly Control Betula nana Growth in Arctic Alaska
- Author
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Buchwal, Agata, Bret-Harte, M. Syndonia, Bailey, Hannah, and Welker, Jeffrey M.
- Published
- 2023
- Full Text
- View/download PDF
11. Three hundred years of snowpack variability in southwestern British Columbia reconstructed from tree‐rings.
- Author
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Mood, Bryan J., Coulthard, Bethany, and Smith, Dan J.
- Subjects
SNOW-water equivalent ,TREE-rings ,SNOW surveys ,LA Nina ,CLIMATE change ,DROUGHTS - Abstract
Recent snow droughts in southwestern British Columbia (BC), Canada, have reduced seasonal streamflow during the typically dry late‐spring and summer months, leading to socio‐economic and ecological impacts that draw attention to the impending consequences of climate change. Knowledge of annual winter snowfall variability within this region is largely derived from a sparse network of short‐duration (≤50 years) snow survey stations. In this paper, we develop an annual April 1 snow water equivalent (SWE) reconstruction from living tree‐ring chronologies that offer a perspective on long‐term natural snowpack variability. The dendrohydrological model estimates the first principal component April 1 SWE for the southwestern regions of BC to 1711. Spectral analysis identified dominant multidecadal April 1 SWE variability over the pre‐instrumental period. The reconstruction successfully captures known instrumental period influences of La Niña oscillations on reconstructed SWE, suggesting that our tree‐ring based the reconstruction has the potential to provide insights on pre‐instrumental ocean–atmosphere links with southwestern BC snowpack dynamics. Runs analysis suggests pre‐instrumental snow droughts have been more than twice as long in duration and severity than during the observed period which indicates the instrumental record may not capture the full range of April 1 SWE variability. The reconstruction provides the first high‐resolution description of SWE over the past 300 years in southwestern BC and is of immediate use to regional water resource managers. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
12. Global assessment of relationships between climate and tree growth.
- Author
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Wilmking, Martin, Maaten‐Theunissen, Marieke, Maaten, Ernst, Scharnweber, Tobias, Buras, Allan, Biermann, Christine, Gurskaya, Marina, Hallinger, Martin, Lange, Jelena, Shetti, Rohan, Smiljanic, Marko, and Trouillier, Mario
- Subjects
TREE growth ,TREE-rings ,ENVIRONMENTAL sciences ,CLIMATOLOGY ,EVOLUTIONARY theories - Abstract
Tree‐ring records provide global high‐resolution information on tree‐species responses to global change, forest carbon and water dynamics, and past climate variability and extremes. The underlying assumption is a stationary (time‐stable), quasi‐linear relationship between tree growth and environment, which however conflicts with basic ecological and evolutionary theory. Indeed, our global assessment of the relevant tree‐ring literature demonstrates non‐stationarity in the majority of tested cases, not limited to specific proxies, environmental parameters, regions or species. Non‐stationarity likely represents the general nature of the relationship between tree‐growth proxies and environment. Studies assuming stationarity however score two times more citations influencing other fields of science and the science–policy interface. To reconcile ecological reality with the application of tree‐ring proxies for climate or environmental estimates, we provide a clarification of the stationarity concept, propose a simple confidence framework for the re‐evaluation of existing studies and recommend the use of a new statistical tool to detect non‐stationarity in tree‐ring proxies. Our contribution is meant to stimulate and facilitate discussion in light of our results to help increase confidence in tree‐ring‐based climate and environmental estimates for science, the public and policymakers. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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13. Bristlecone Pine Maximum Latewood Density as a Superior Proxy for Millennium‐Length Temperature Reconstructions.
- Author
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De Mil, T., Matskovsky, V., Salzer, M., Corluy, L., Verschuren, L., Pearson, C., Van Hoorebeke, L., Trouet, V., and Van den Bulcke, J.
- Subjects
WOOD density ,WOOD ,TREE growth ,DENDROCLIMATOLOGY ,CONIFERS ,TREE-rings - Abstract
Bristlecone pine (Pinus longaeva) (PILO) trees exhibit exceptional longevity. Their tree‐ring width (TRW) series offer valuable insights into climatic variability. Maximum latewood density (MXD) typically correlates better with temperature variations than TRW, yet PILO MXD records are non‐existent due to methodological challenges related to tree‐ring structure. Here, we used an X‐ray Computed Tomography (X‐ray CT) toolchain on 51 PILO cores from the California White Mountains to build a chronology that correlates significantly (r = 0.66, p < 0.01) with warm‐season (March‐September) temperature over a large spatial extent. This led to the first X‐ray CT‐based temperature reconstruction (1625–2005 CE). Good reconstruction skill (RE = 0.51, CE = 0.32) shows that extending MXD records across the full length of the PILO archive could yield a robust warm‐season temperature proxy for the American Southwest over millennia. This breakthrough opens avenues for measuring MXD in other challenging conifers, increasing our understanding of past climate further, particularly in lower latitudes. Plain Language Summary: Ancient Bristlecone pine trees can live for several millennia and hold invaluable climate information. Their annual rings were used to develop millennium‐length records of the Holocene climate. Maximum latewood density (MXD), which is the highest wood density value in the latewood of a tree ring, has been shown to closely follow summer temperature in different conifer species, but not yet in Bristlecone pine. The gnarly and twisted growth of these ancient trees has presented significant hurdles for MXD analysis. Here we apply an X‐ray Computed Tomography toolchain that allows us to 3D scan through the tissue of a tree ring and to map MXD variations. Using this new technique, we were able to reconstruct warm‐season temperature for the American Southwest back to 1625 CE. With these findings, we are confident that a full‐length reconstruction (back to 2575 BCE) can yield the longest annually resolved temperature reconstruction for this continent. Key Points: We present the first X‐ray Computed Tomography‐derived maximum latewood density‐based temperature reconstruction using Bristlecone pine tree coresBristlecone pine maximum latewood density is a reliable proxy for warm‐season temperature over a large part of the American SouthwestOur reconstruction (1625–2005 CE) contains low‐frequency variability and can be prolonged over a large part of the Holocene [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
14. Elevational variations in climate warming impacts on West Himalayan fir growth
- Author
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Sohar, Kristina, Altman, Jan, Kopecký, Martin, Pejcha, Vít, Rai, Samresh, Fibich, Pavel, and Doležal, Jiří
- Published
- 2024
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- View/download PDF
15. Tree-ring based summer temperature variability since 1790 CE in the Hindu Kush region of northern Pakistan
- Author
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Asad, Fayaz, Adil, Muhammad, Shahid, Sabrina, Khan, Nasrullah, Huang, Ru, and Zhu, Haifeng
- Published
- 2024
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16. BLUE INTENSITY IN LARIX SIBIRICA TREE RINGS AS A NEW PALAEOCLIMATE PROXY IN ALTAI, RUSSIA.
- Author
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Ovchinnikov, Dmitriy, Eremina, Anastasiya, and Ovchinnikov, Svjatoslav
- Subjects
PLANT cell walls ,DENDROCLIMATOLOGY ,AUTOCORRELATION (Statistics) ,PALEOCLIMATOLOGY ,STANDARD deviations - Abstract
Dendroclimatic studies based on the use of various indicators of annual tree-ring structure (width, maximum density, cell wall thickness, lumen size etc.) have become widespread over the past decade. However, reconstructions of climatic characteristics revealed limitations associated with the use of both the width and density of annual rings. In particular, annual ring width, in the high latitudes of the Northern Hemisphere and in mountain regions, is usually closely related either with June, or June and July air temperature. The tree-ring maximum density is closely related with June-August or May-August temperature, which relationship improves past climate reconstruction. Structural characteristics at a cell level (cell wall thickness, lumen size, etc.) are more suitable for dendrophysiological and dendroecological studies. Blue intensity (BI) is a new parameter of annual ring structure used in dendrochronological studies. BI correlates well with annual ring maximum density. BI key advantages are in that it is fairly inexpensive, user-friendly and timesaving concerning data acquirement. Studies done in Europe and North America show a high BI potential regarding reconstruction of past climate, in particular, of that of air temperature. This paper discusses the problems of use of BI as a paleoclimatic indicator for the mountainous areas of southern Siberia (Altai Region, Russia). BI was calculated for tree-rings of the Siberian larch trees growing in Altai mountains. As a result, a local 232-yr (1783-2014) BI-chronology of Larix sibirica L. was built for an area located in Altai Mt., southern Siberia. BI- chronology was tested for quality by standard statistical methods used in dendrochronology. Mean sensitivity (MS), standard deviation (SD), first order autocorrelation (AC1) and other indicators were used to test BI time series. The correlation between individual time series ranged 0.5 to 0.65, whereas the ranges were 0.11-0.21 for MS, 0.16-0.21 for SD, and 0.86-0.88 for AC1. The statistical data were similar regarding tree-ring maximum density (MXD). AC1 was similar to that for tree- ring width (TRW). A linear regression, negative exponential line, and different spline functions were used to calculate standard (STD) and residual (RES) BI-chronologies. STD-chronology had an autocorrelation and RES-chronology had a negative autocorrelation. Preliminary studies of Siberian larch showed a high potential of BI as a paleoclimatic proxy for dendroecological and dendroclimatological studies conducted in the mountain regions of southern Siberia (Altai Mt., Russia). [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
17. A tree ring-based winter temperature reconstruction for the southeastern Tibetan Plateau since 1340 CE.
- Author
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Huang, Ru, Zhu, Haifeng, Liang, Eryuan, Liu, Bo, Shi, Jiangfeng, Zhang, Ruibo, Yuan, Yujiang, and Grießinger, Jussi
- Subjects
CLIMATE change ,SOLAR activity ,TEMPERATURE ,VOLCANIC eruptions ,PLATEAUS ,WINTER ,PALEOHYDROLOGY - Abstract
Climatic change is exhibiting significant effects on the ecosystem of the Tibetan Plateau (TP), a climate-sensitive area. In particularly, winter frost, freezing events and snow avalanche frequently causing severe effects on ecosystem and social economy, however, few long-term winter temperature records or reconstructions hinder a better understanding on variations in winter temperature in the vast area of the TP. In this paper, we present a minimum winter (November–February) temperature reconstruction for the past 668 years based on a tree-ring network (12 new tree-ring chronologies) on the southeastern TP. The reconstruction exhibits decadal to inter-decadal temperature variability, with cold periods occurring in 1423–1508, 1592–1651, 1729–1768, 1798–1847, 1892–1927, and 1958–1981, and warm periods in 1340–1422, 1509–1570, 1652–1728, 1769–1797, 1848–1891, 1928–1957, and 1982–2007. As suggested by the comparisons with existing winter temperature series and spatial correlations with Climatic Research Unit gridded data, our reconstruction is reliable and indicative, and it can represent large-scale winter temperature variability on the southeastern TP. Furthermore, it shows an overall agreement with winter temperature from the northeastern TP on decadal to inter-decadal timescales. It also shows the possible effects of volcanic eruption and reducing solar activity on the winter temperature variability for the past six centuries on the southeastern TP. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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18. Interdecadal Pacific Oscillation reconstructed from trans-Pacific tree rings: 1350–2004 CE.
- Author
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Buckley, Brendan M., Ummenhofer, C. C., D'Arrigo, R. D., Hansen, K. G., Truong, L. H., Le, C. N., and Stahle, D. K.
- Subjects
TREE-rings ,OSCILLATIONS ,ICE cores ,ATLASES ,ANTARCTIC ice ,MODES of variability (Climatology) ,CYPRESS - Abstract
The interdecadal Pacific Oscillation (IPO) represents the decadal mode of the El Niño-Southern Oscillation phenomenon. As such the IPO is one of the dominant modes of decadal climate variability on both sides of the Pacific Ocean basin. For this paper we utilized a newly developed tree-ring data network comprised of five multi-centennial Vietnamese cypress ring-width chronologies that range from around 11°N–23°N latitude. We combined these data with an average of tree-ring derived drought indices from the North American Drought Atlas over the south central USA, from a box that spans from 27.5°N–35.0°N, 85.0°–110.0°W and contains 55 gridpoints and more than 100 tree ring site chronologies, these 2 locations exhibit rainfall variations that are strongly, negatively correlated with each other and are representative of the influence of the IPO on terrestrial rainfall. The final reconstruction model, weighted most heavily on the three most southerly of the five Vietnamese cypress records, spans from 1350 to 2004, and explains nearly 57% of the variance in the original IPO data for the 5-month season of October–February. The reconstruction model passes all standard statistical tests using a split calibration-verification scheme. We reveal 15 positive and 15 negative phase shifts of the IPO prior to the period of instrumentation, suggesting that the IPO has been active for at least the past seven centuries with varying degrees of intensity. We compare our reconstruction with two related millennial records: the MacDonald and Case (Geophys Res Lett 32(8):L08703, 2005) tree ring-derived reconstruction of the Pacific Decadal Oscillation, and an ice core-derived reconstruction of the IPO from the Law Dome Ice core in Antarctica by Vance et al. (Geophys Res Lett 33(6):L06712, 2015). While there is good general agreement with the latter record, there are three key periods of the past where the two records are out of phase, and we explore the reasons for this disparity. Direct comparison with the related Tripole Index (TPI) shows weaker correlation, likely owing to the stronger relationship between our tree ring data and the equatorial Pacific region relative to the north and south regions of the Pacific that combine to comprise the TPI calculation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
19. A dendroclimatological study of east- and west-facing slopes in mountainous areas subjected to strong air pollution (the Sudetes, Central Europe).
- Author
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Opała-Owczarek, Magdalena, Błaś, Marek, Owczarek, Piotr, Sobik, Mieczysław, and Godek, Michał
- Subjects
DENDROCLIMATOLOGY ,AIR pollution ,SLOPES (Physical geography) - Abstract
The Sudetes Mountains (Central Europe) were under a particularly intense long-term air pollution load during the 1970s and 1980s. Intense industrial activity in this area led to large-scale forest dieback and reductions in tree growth rates, potentially limiting the use of tree-ring data from this region in dendroclimatic research. In this paper, ring-width chronologies were constructed for 493 Norway spruce trees (Picea abies L. Karst.) from 17 sampling sites within five major mountain ranges in the Sudetes Mountains of Poland. Growth-climate response data indicate that April‒July temperatures are the main factor affecting radial growth of trees in the study area. Our data also indicate the strong influence of slope aspect on temperature signal strength. The lowest correlation values were obtained for sites located on western slopes with effective fog deposition, which are strongly affected by pollution. An appropriate sampling strategy resulted in the creation of a temperature-sensitive proxy record (rAMJJ = 0.70), exceptional for areas under strong pressure from human activity. Based on a regional master chronology, growing season (April‒July) temperatures over the past 200 years were then reconstructed. Four warm and four cold periods were distinguished and compared with other reconstructions and long-term instrumental data. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
20. EXAMINATION OF STABLE CARBON AND OXYGEN ISOTOPIC VARIABILITY IN THE CELLULOSE AND WHOLEWOOD OF Castanea sativa Mill., Fagus sylvatica L., Pinus sylvestris L. AND Quercus robur L.
- Author
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SLADDEN, B., LOADER, N. J., YOUNG, G. H. F., and McCARROLL, D.
- Subjects
OXYGEN isotopes ,CARBON content of plants ,CELLULOSE ,CHESTNUT ,EUROPEAN beech ,SCOTS pine ,ENGLISH oak ,DENDROCLIMATOLOGY - Abstract
Copyright of Acta Silvae et Ligni is the property of Biotechnical Faculty, Slovenian Forestry Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
- Full Text
- View/download PDF
21. A MACHINE LEARNING APPROACH TO ANALYZING THE RELATIONSHIP BETWEEN TEMPERATURES AND MULTI-PROXY TREE-RING RECORDS.
- Author
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JEVŠENAK, JERNEJ, DŽEROSKI, SAŠO, ZAVADLAV, SAŠA, and LEVANIČ, TOM
- Subjects
MACHINE learning ,TREE-rings ,DENDROCLIMATOLOGY ,ARTIFICIAL neural networks ,REGRESSION trees - Abstract
Machine learning (ML) is a widely unexplored field in dendroclimatology, but it is a powerful tool that might improve the accuracy of climate reconstructions. In this paper, different ML algorithms are compared to climate reconstruction from tree-ring proxies. The algorithms considered are multiple linear regression (MLR), artificial neural networks (ANN), model trees (MT), bagging of model trees (BMT), and random forests of regression trees (RF). April-May mean temperature at a Quercus robur stand in Slovenia is predicted with mean vessel area (MVA, correlation coefficient with April-May mean temperature, r = 0.70, p < 0.001) and earlywood width (EW, r = -0.28, p < 0.05). Similarly, June-August mean temperature is predicted with stable carbon isotope (δ
13 C, r = 0.72, p < 0.001), stable oxygen isotope (δ18 O, r = 0.32, p < 0.05) and tree-ring width (TRW, r = 0.11, p > 0.05 (ns)) chronologies. The predictive performance of ML algorithms was estimated by 3-fold cross-validation repeated 100 times. In both spring and summer temperature models, BMT performed best respectively in 62% and 52% of the 100 repetitions. The second-best method was ANN. Although BMT gave the best validation results, the differences in the models' performances were minor. We therefore recommend always comparing different ML regression techniques and selecting the optimal one for applications in dendroclimatology. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
22. УТИЦАЈ ТЕМПЕРАТУРЕ ВАЗДУХА И ПАДАВИНА НА ПРИРАСТ ЦРНОГ БОРА (Pinus nigra J. F. Arnold): СТУДИЈА СЛУЧАЈА СА ПОДРУЧЈА ПЛАНИНЕ РУДНИК.
- Author
-
Стајић, Бранко and Казимировић, Марко
- Subjects
AUSTRIAN pine ,TREE-rings ,METEOROLOGICAL precipitation ,TEMPERATURE - Abstract
Copyright of Bulletin of the Faculty of Forestry / Glasnik Šumarskog Fakulteta is the property of University of Belgrade, Faculty of Forestry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
- Full Text
- View/download PDF
23. ДЕНДРОКЛИМАТОЛОШКА АНАЛИЗА РАСТА ЈЕЛЕ (Abies Alba MILL.) НА ПОДРУЧЈУ ПЛАНИНЕ БОРЈА, БОСНА И ХЕРЦЕГОВИНА.
- Author
-
Јовић, Горан, Дукић, Војислав, Стајић, Бранко, Казимировић, Марко, and Петровић, Данијела
- Subjects
FIR ,STATISTICAL correlation ,TREE growth ,ELECTRONIC data processing ,DROUGHTS ,DROUGHT forecasting - Abstract
Copyright of Bulletin of the Faculty of Forestry / Glasnik Šumarskog Fakulteta is the property of University of Belgrade, Faculty of Forestry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
- Full Text
- View/download PDF
24. Latitudinal and temporal shifts in the radial growth-climate response of Siberian larch in the Polar Urals.
- Author
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Kukarskih, Vladimir V., Devi, Nadezhda M., Moiseev, Pavel A., Grigoriev, Andrey A., and Bubnov, Maksim O.
- Subjects
TREE-rings ,DENDROCLIMATOLOGY ,SIBERIAN larch ,CLIMATE change ,LARCHES - Abstract
This paper presents a dendroclimatic analysis of Siberian larch trees sampled along a latitudinal 260-km transect located in the Polar Urals, Russia. Three standardised chronologies were built over a length of 230-293 years using 79 individual tree-ring chronologies collected in the southern, middle and northern parts of the Polar Urals. Bootstrapped correlation functions showed that the annual growth of the larches was mainly influenced by the air temperatures in June and July. The relative role of the temperatures increased from south to north. Daily air temperature data analysis revealed that the duration of the growing season in the northern part of the Polar Urals is 24 days less than that in the southern part. At the present time, air temperatures exceeded threshold of 8°C, 5 days earlier than it did in the beginning of the 20th century. In response to the increase in the duration of the growing season and the changing winter conditions in the Polar Urals over the last 130 years, radial growth-temperature relationships in larches have weakened; this effect was strongly pronounced in the southern part of the Polar Urals. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
25. PREFACE: CENTER FOR MEDITERRANEAN ARCHAEOLOGY AND THE ENVIRONMENT - SPECIAL JOINT ISSUE OF RADIOCARBON AND TREE-RING RESEARCH.
- Author
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PEARSON, CHARLOTTE L. and KUHN, STEVEN L.
- Subjects
HACKBERRY ,KILNS ,DENDROCLIMATOLOGY - Abstract
An introduction is presented which discusses various papers within the issue including carbon-14 and isotopic composition of hackberry endocarps at the Neolithic site in central Turkey, study of Hellenistic and Early Roman kilns in Greece, and review of dendroclimatic research across North Africa.
- Published
- 2014
- Full Text
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26. Blue rings in Bristlecone pine as a high resolution indicator of past cooling events
- Author
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Siekacz, Liliana, Pearson, Charlotte, Salzer, Matthew, Soja-Kukieła, Natalia, and Koprowski, Marcin
- Published
- 2024
- Full Text
- View/download PDF
27. Statistical treatment for the wet bias in tree-ring chronologies: a case study from the Interior West, USA.
- Author
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Sun, Yan, Bekker, Matthew, Derose, R., Kjelgren, Roger, and Wang, S.-y.
- Subjects
TREE-rings ,DENDROCHRONOLOGY ,DENDROCLIMATOLOGY ,REGRESSION analysis ,SATURATION vapor pressure - Abstract
Dendroclimatic research has long assumed a linear relationship between tree-ring increment and climate variables. However, ring width frequently underestimates extremely wet years, a phenomenon we refer to as 'wet bias'. In this paper, we present statistical evidence for wet bias that is obscured by the assumption of linearity. To improve tree-ring-climate modeling, we take into account wet bias by introducing two modified linear regression models: a linear spline regression (LSR) and a likelihood-based wet bias adjusted linear regression (WBALR), in comparison with a quadratic regression (QR) model. Using gridded precipitation data and tree-ring indices of multiple species from various sites in Utah, both LSR and WBALR show a significant improvement over the linear regression model and out-perform QR in terms of in-sample $${R}^{2}$$ and out-of-sample MSE. This further shows that the wet bias emerges from nonlinearity of tree-ring chronologies in reconstructing precipitation. The pattern and extent of wet bias varies by species, by site, and by precipitation regime, making it difficult to generalize the mechanisms behind its cause. However, it is likely that dis-coupling between precipitation amounts (e.g., percent received as rain/snow or percent infiltrating the soil) and its availability to trees (e.g., root zone dynamics), is the primary mechanism driving wet bias. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
28. Análisis dendroclimático y modelización cartográfica de la respuesta climática de Fagus sylvatica en su crecimiento, en un sector de la montaña cantábrica central.
- Author
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Lallana-Llorente, Víctor
- Abstract
Copyright of Investigaciones Geograficas is the property of Universidad de Alicante, Instituto Universitario de Geografia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2017
- Full Text
- View/download PDF
29. Temperature reconstruction based on 361 year old dendrochronology of Platycladus orientalis (L.) franco in the Wula Mountains, China.
- Author
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Sun, Bolin, Ma, Long, Liu, Tingxi, Huang, Xing, and Zhou, Ying
- Subjects
- *
DENDROCHRONOLOGY , *TREE-rings , *TEMPERATURE , *HUMIDITY , *LOW temperatures - Abstract
The northern edge of the East Asian monsoon region is also a transition zone of temperate continental and monsoon climate, which is a sensitive zone of global climate and ecological environment change. It is an urgent problem to find out the long-term climate change rules of this region. Using 101 tree core samples obtained from 54 trees, a 343-year tree-ring width chronology of the Platycladus orientalis (L.) Franco (1673–2016) in the Wula Mountains, Inner Mongolia, China was established. The analysis shows that the radial growth of P. orientalis is closely related to hydrothermal conditions, the average minimum temperature and relative humidity are the main factors that determine the growth of P. orientalis. Based on the strong correlation between the tree-ring indices and the annual average minimum temperature (r = −0.870, p < 0.001), we reconstructed an average annual minimum temperature series from 1673 to 2016 using a linear regression equation, and the reconstructed equation can explain 75.724% of the variance, respectively. According to the data from the past 343 years, the changes in the annual average minimum temperature series had the cycles of 58.6-, 7.7-, 3.4-, 3.1-, 2.2-, and 2.1-years; the series showed three warm periods (1824–1830, 1909–1922, and 1986–2011) and 4 cold periods (1703–1712, 1731–1738, 1754–1763, and 1937–1951). The low temperature periods recorded in the reconstructed series for the 17th and 18th centuries are consistent with the Little Ice Age that occurred in the northern hemisphere, and the heating rate significantly increased at the end of the 20th century. In addition, the cold and warm periods recorded by the reconstruction result is basically consistent with the extreme climate events recorded in the historical documents of the region and the reconstruction results in other regions. In this paper, the world's first chronology of P. orientalis tree ring width was established. A historical sequence of annual average minimum temperature of 343 years was reconstructed in a typical region of the East Asian monsoon climate. It fills in the blank of reconstruction sequence and variation characteristics of mean minimum temperature in the northern edge of East Asian monsoon and transition zone of temperate continental and monsoon climate in recent four centuries. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
30. Climatic implications in earlywood and latewood width indices of Chinese pine in north central China.
- Author
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Yang, Kaixuan, Zhang, Junzhou, Fan, Haowen, and Yan, Yuan
- Abstract
Latewood width (LWW) indices of trees are considered a reliable proxy of summer precipitation in the Northern Hemisphere. However, the strong coupling and high correlation between earlywood width (EWW) and LWW indices often prevent registration of climate signals of the LWW index. In this study, 328-year-long earlywood width and latewood width chronologies were developed from Chinese pine at two sites in the Hasi Mountains, north central China. The climate responses of these chronologies were analyzed and the LWW index used to derive summer precipitation signals. Correlation analyses showed that LWW was particularly influenced by earlywood growth and recorded stronger climate signals of the previous year as EWW, rather than those of the current year with infrequent summer climate signals. However, after removing the effect of earlywood growth using a simple regression model, the adjusted LWW chronology (LWW
adj ) showed a strong relationship with July precipitation in dry years. This suggests that the LWWadj chronology has the potential to be used to investigate long-term variability in summer precipitation in drought-limited regions. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
31. INFLUENCE OF CLIMATE AND ROOT ZONE SOIL WETNESS ON RADIAL GROWTH OF BLACK PINE (Pinus nigra Arnold subsp. pallasiana) AT ARIT (BARTIN) IN THE WESTERN BLACK SEA REGION OF TÜRKİYE.
- Author
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YAMAN, Barbaros, PULAT, Esra, DAŞDEMıR, İsmet, and YEŞİLBAŞ, Yaǧmur
- Subjects
AUSTRIAN pine ,FORESTRY & climate ,SOIL moisture ,DENDROCHRONOLOGY - Abstract
Copyright of Journal of Forestry Society of Croatia / Sumarski List Hrvatskoga Sumarskoga Drustva is the property of Forestry Society of Croatia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
32. Climate Response of Tree Radial Growth at Different Timescales in the Qinling Mountains.
- Author
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Sun, Changfeng and Liu, Yu
- Subjects
CLIMATE change ,METEOROLOGICAL precipitation ,DENDROCLIMATOLOGY ,PALEOCLIMATOLOGY - Abstract
The analysis of the tree radial growth response to climate is crucial for dendroclimatological research. However, the response relationships between tree-ring indices and climatic factors at different timescales are not yet clear. In this study, the tree-ring width of Huashan pine (Pinus armandii) from Huashan in the Qinling Mountains, north-central China, was used to explore the response differences of tree growth to climatic factors at daily, pentad (5 days), dekad (10 days) and monthly timescales. Correlation function and linear regression analysis were applied in this paper. The tree-ring width showed a more sensitive response to daily and pentad climatic factors. With the timescale decreasing, the absolute value of the maximum correlation coefficient between the tree-ring data and precipitation increases as well as temperature (mean, minimum and maximum temperature). Compared to the other three timescales, pentad was more suitable for analysing the response of tree growth to climate. Relative to the monthly climate data, the association between the tree-ring data and the pentad climate data was more remarkable and accurate, and the reconstruction function based on the pentad climate was also more reliable and stable. We found that the major climatic factor limiting Huashan pine growth was the precipitation of pentads 20–35 (from April 6 to June 24) rather than the well-known April–June precipitation. The pentad was also proved to be a better timescale for analysing the climate and tree growth in the western and eastern Qinling Mountains. The formation of the earlywood density of Chinese pine (Pinus tabulaeformis) from Shimenshan in western Qinling was mainly affected by the maximum temperature of pentads 28–32 (from May 16 to June 9). The maximum temperature of pentads 28–33 (from May 16 to June 14) was the major factor affecting the ring width of Chinese pine from Shirenshan in eastern Qinling. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
33. Tuning the Voices of a Choir: Detecting Ecological Gradients in Time-Series Populations.
- Author
-
Buras, Allan, van der Maaten-Theunissen, Marieke, van der Maaten, Ernst, Ahlgrimm, Svenja, Hermann, Philipp, Simard, Sonia, Heinrich, Ingo, Helle, Gerd, Unterseher, Martin, Schnittler, Martin, Eusemann, Pascal, and Wilmking, Martin
- Subjects
MULTIPLE correspondence analysis (Statistics) ,DENDROCHRONOLOGY ,ARCHAEOLOGICAL dating ,TIME series analysis ,MONTE Carlo method - Abstract
This paper introduces a new approach–the Principal Component Gradient Analysis (PCGA)–to detect ecological gradients in time-series populations, i.e. several time-series originating from different individuals of a population. Detection of ecological gradients is of particular importance when dealing with time-series from heterogeneous populations which express differing trends. PCGA makes use of polar coordinates of loadings from the first two axes obtained by principal component analysis (PCA) to define groups of similar trends. Based on the mean inter-series correlation (rbar) the gain of increasing a common underlying signal by PCGA groups is quantified using Monte Carlo Simulations. In terms of validation PCGA is compared to three other existing approaches. Focusing on dendrochronological examples, PCGA is shown to correctly determine population gradients and in particular cases to be advantageous over other considered methods. Furthermore, PCGA groups in each example allowed for enhancing the strength of a common underlying signal and comparably well as hierarchical cluster analysis. Our results indicate that PCGA potentially allows for a better understanding of mechanisms causing time-series population gradients as well as objectively enhancing the performance of climate transfer functions in dendroclimatology. While our examples highlight the relevance of PCGA to the field of dendrochronology, we believe that also other disciplines working with data of comparable structure may benefit from PCGA. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
34. Effect of various climate databases on the results of dendroclimatic analysis.
- Author
-
Sitko, Roman, Vido, Jaroslav, Škvarenina, Jaroslav, Pichler, Viliam, Scheer, Ĺubomír, Škvareninová, Jana, and Nalevanková, Paulína
- Subjects
SEASONAL temperature variations ,METEOROLOGICAL precipitation ,DENDROCLIMATOLOGY - Abstract
The paper deals with the comparison of the time series drawn from different climate databases. We compared the observed data with the modeled data of monthly and seasonal temperature means and precipitation totals. Reliable and longest available time series of such data represent the basic starting point of dendroclimatic analyses. We evaluated the differences in the growth response of spruce derived using different databases of the considered climatic variables. The stem cores used to derive the cross-correlation function were taken from Hårås locality situated in the boreal zone of the Swedish part of Lapland. We compared the observed records from the nearest weather stations situated 18,40,70 and 110 km away from the locality with the interpolated data from four modeled temperature databases and four modeled precipitation databases generated by KNMI Climate Explorer. The spatial resolution of the modeled databases was 0.5°x0.5°of latitude and longitude or Io x Io respectively. The evaluation revealed that in all modeled databases systematic errors of different magnitudes occurred. We also found that the radial increments of spruce correlated more tightly with the temperature than with the precipitation in the area of interest. Hence, in the conditions of the boreal zone, temperature could be a more important factor with regard to tree-ring formation. Because of higher spatial variability seen in precipitation data when compared to temperature data, we conclude that the nearest weather station is the most suitable for dendroclimatic analysis leaning on precipitation. Drawing on these results we recommend that the modeled precipitation and temperature databases examined in our study are used for dendroclimatic analyses within areas featuring a sparse network of weather stations. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
35. Douglas-fir climate sensitivity at two contrasting sites along the southern limit of the European planting range
- Author
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Castaldi, Cristiano, Marchi, Maurizio, Vacchiano, Giorgio, and Corona, Piermaria
- Published
- 2020
- Full Text
- View/download PDF
36. The Potential of Deriving Tree-Ring-Based Field Reconstructions of Droughts and Pluvials over Fennoscandia*,+.
- Author
-
Seftigen, Kristina, Cook, Edward R., Linderholm, Hans W., Fuentes, Mauricio, and Björklund, Jesper
- Subjects
DENDROCLIMATOLOGY ,DROUGHTS ,PLUVIAL periods ,CLIMATE change ,REGRESSION analysis - Abstract
Moisture availability has been identified as one of the most important factors in the context of future climate change. This paper explores the potential of applying a multiproxy approach to dendroclimatology to infer the twentieth-century moisture variability over Fennoscandia. Fields of the warm-season (June-August) standardized precipitation evapotranspiration index (SPEI) were developed from a dense network of precipitation-sensitive annually resolved tree-ring width (TRW), maximum density (MXD), and stable carbon (δ
13 C) and oxygen (δ18 O) isotope chronologies using a point-by-point local regression technique (PPR). Two different approaches were tested for selecting candidate tree-ring predictors of SPEI for each gridpoint reconstruction: a search radius method and a search spatial correlation contour method. As confirmed by a range of metrics of reconstruction fidelity, both methods produced reconstructions showing a remarkably high accuracy in a temporal sense, but with some minor regional differences. As a whole, the spatial skill of the reconstructed fields was generally quite good, showing the greatest performance in the central and southern parts of the target region. Lower reconstruction skills were observed in northern part of the study domain. Regional-scale moisture anomalies were best captured by the reconstructions, while local-scale features were not as well represented. The authors speculate that a spatially and temporally varying tree-ring proxy response to temperature and precipitation in the region may cause some uncertainties in a Fennoscandian hydroclimatic reconstruction; this needs further investigation. Overall, this study shows a great potential for making long-term spatiotemporal reconstructions of moisture variability for the Fennoscandian region using tree-ring data. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
37. Specification and estimation of the transfer function in dendroclimatological reconstructions.
- Author
-
Auffhammer, Maximilian, Li, Bo, Wright, Brian, and Yoo, Seung-Jick
- Subjects
TRANSFER functions ,DENDROCLIMATOLOGY ,MONTE Carlo method ,REGRESSION analysis ,MEASUREMENT errors ,PALEOCLIMATOLOGY - Abstract
We identify two issues with the reverse regression approach as implemented in several classic reconstructions of past climate fluctuations from dendroclimatologcical data series. First, instead of estimating the causal relationship between the proxy, which is measured with significant error, as function of climate and formally inverting the relationship, most papers estimate the inverted relationship directly. This leads to biased coefficients and reconstructions with artificially low variance. Second, we show that inversion of the relationship is often done incorrectly when the underlying causal relationship is dynamic in nature. We show analytically as well as using Monte Carlo experiments and actual tree ring data, that the reverse regression method results in biased coefficients, reconstructions with artificially low variance and overly smooth reconstructions. We further demonstrate that correct application of the inverse regression method is preferred. However, if the measurement error in the tree ring index is significant, neither method provides reliable reconstructions. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
38. October to July precipitation reconstruction for Burabai region (Kazakhstan) since 1744
- Author
-
Akkemik, Ünal, Köse, Nesibe, Kopabayeva, Arailym, and Mazarzhanova, Kuralay
- Published
- 2020
- Full Text
- View/download PDF
39. Frost rings as time markers in Northern Hemisphere tree-ring chronologies, with special reference to the 1627 BC and AD 536 events.
- Author
-
Helama, Samuli
- Abstract
This paper discusses the findings of frost rings in three supra-long Northern Hemisphere tree-ring chronologies. Comparison between recently published data representing bristlecone pine from western North America, Scots pine from northern Fennoscandia and Siberian larch and Siberian spruce from the Yamal Peninsula shows the rare occurrence of frost rings dated to exactly same calendar years in more than one of these chronologies. The frost ring dates evident in all three datasets are dated to 1627 BC and AD 536. Previously, tree-ring features indicative of adverse growing conditions around 1627 BC have been discussed in the literature. Here, it is emphasised that the frost rings 1627 BC and AD 536 are dated to exactly same calendar year in all available tree-ring records, which demonstrates the value of such an event as a definitive time marker. Other major events of frost rings from multiple sites were dated to 421 BC, 251 BC, AD 627, AD 884, AD 985, AD 1109, AD 1259, AD 1453, AD 1601 and AD 1884. Similar to 1627 BC and AD 536, some of these events have been attributed to volcanic forcing and climate anomalies that led to human consequences and disasters. The case of the 1650 s BC appears different, with possibility of more than one major eruptions, as suggested by frost ring events dated to 1656 BC and 1653 BC in Yamal and western USA, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
40. Warm season temperature reconstruction in North China based on the tree-ring blue intensity of Picea meyeri.
- Author
-
Chen, Qiaomei, Yue, Weipeng, Chen, Feng, Hadad, Martín, Roig, Fidel, Zhao, Xiaoen, Hu, Mao, and Cao, Honghua
- Abstract
In the past 30 years, observational climate datasets reveal a significant a drying and warming trend over in North China. Understanding of climatic variability over North China and its driving mechanism in a long-term perspective is, however, limited to a few sites only, especially the lack of temperature reconstructions based on latewood density and blue intensity. In this study, we developed a 281-year latewood blue intensity chronology based on 45 cores of Picea meyeri in western North China. Based on the discovery that the warm season (May–August) mean maximum temperature is the main controlling factor affecting the change in blue light reflection intensity, we established a regression model that explained 37% of the variance during the calibration period (1950–2020), allowing to trace the mean maximum temperature up to 1760 CE. From the past 261 years, we identified seven persistent high temperature periods (1760–1773, 1778–1796, 1805–1814, 1869–1880, 1889–1934, 1984–2000, 2004–2020) and three persistent low temperature periods (1815–1868, 1935–1963, 1969–1983) in North China. Comparisons of a nearby temperature reconstructions and climate gridded data indicate that our reconstruction record a wide range of temperature variations in North China. The analysis of links between large-scale climatic variation and the temperature reconstruction showed that there is a relationship between extremes in the warm season temperature and anomalous SSTs in the equatorial eastern Pacific, and implied that the extremes in the warm season temperature in North China will be intensified under future global warming. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
41. Dendrochronological Analysis of One-Seeded and Intermediate Hawthorn Response to Climate in Poland.
- Author
-
Cedro, Anna and Cedro, Bernard
- Subjects
HAWTHORNS ,TREE-rings ,HEAT waves (Meteorology) ,TREE age ,ATMOSPHERIC temperature ,DENDROCHRONOLOGY ,ASH (Tree) ,RAINFALL - Abstract
Although the hawthorn is not a forest-forming species, and it has no high economic significance, it is a very valuable component of forests, mid-field woodlots or roadside avenues. The literature, however, lacks information on the growth rate, growth phases, or growth–climate–habitat relationship for trees of this genus. This work aimed to establish the rate of growth of Craraegus monogyna and C. xmedia Bechst growing in various parts of Poland, in various habitats; analyze the growth–climate relationship; and distinguish dendrochronological regions for these species. Samples were taken using a Pressler borer from nine populations growing in different parts of Poland, from a total of 192 trees (359 samples). The tree-ring width was measured down to 0.01 mm. The average tree-ring width in the studied hawthorn populations ranged from 1.42 to 3.25 mm/year. Using well-established cross-dating methods, nine local chronologies were compiled with tree ages between 45 and 72 years. Dendroclimatic analyses (pointer year analysis, correlation and response function analysis) were performed for a 33-year period from 1988 to 2020, for which all local chronologies displayed EPS > 0.85. The tree-ring width in the hawthorn populations depended mostly on temperature and rainfall through the May–August period. High rainfall and the lack of heat waves through these months cause an increase in cambial activity and the formation of wide tree rings. Conversely, rainfall shortages through this period, in conjunction with high air temperatures, caused growth depressions. Cluster analysis enabled the identification of two dendrochronological regions among the hawthorn in Poland: a western and eastern region, and a single site (CI), whose separation was most likely caused by contrasting habitat and genetic conditions. The obtained results highlight the need for further study of these species in Poland and other countries. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. Dendrochronology and climatic signals in the wood of Nectandra oppositifolia from a dense rain forest in southern Brazil
- Author
-
Granato-Souza, Daniela, Adenesky-Filho, Eduardo, and Esemann-Quadros, Karin
- Published
- 2019
- Full Text
- View/download PDF
43. A warm-season drought reconstruction in central-northern Pakistan inferred from tree rings since 1670 CE and its possible climatic mechanism
- Author
-
Khan, Adam, Chen, Feng, Zhang, Heli, Saleem, Sidra, Ali, Hamada E., Yue, Weipeng, and Hadad, Martín
- Published
- 2024
- Full Text
- View/download PDF
44. THE INFLUENCE OF COMPETITION IN THE GROWTH-CLIMATE RELATIONSHIP OF Pinus taeda: A CASE STUDY IN SOUTHERN BRAZIL.
- Author
-
Schons, Cristine Tagliapietra, Arnoni Costa, Emanuel, and Guimarães Finger, César Augusto
- Subjects
- *
LOBLOLLY pine , *TREE growth , *TREE-rings , *FOREST management , *WATER supply , *CLIMATE change - Abstract
Understanding how climate affects tree growth is crucial for assessing climate change impacts on forests. Furthermore, trees in more competitive environments appear to respond to climate differently than trees in less competitive environments. An important tool for investigating the growth-environment relationships is tree ring dating. This study aimed to characterize the climatic factors that affect Pinus taeda growth in southern Brazil in two distinct stand types: open growth trees and competing trees. We hypothesized that competing trees present more vulnerable responses to climate variability than open growth trees. Thus, we used increment borers to access long-term growth through tree rings. Pearson’s correlation was applied to compare radial growth with monthly and annual climatic data. The chronologies generated for the two environments present similar year-to-year growth patterns. However, competing trees are more sensitive under limiting climate conditions than open growth trees. Water availability during the current spring/summer was the primary climate constraint for P. taeda growth in the region, followed by high temperatures during the summer, probably due to photosynthetic restrictions. The paper provides additional information on climatic factors that contribute to growth models and reports an important research field, considering planning forest management in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
45. The growth of seven Abies grandis provenances in the climatic conditions of the Polish Carpathian Mountains.
- Author
-
Wilczyński, Sławomir and Kulej, Marian
- Subjects
- *
DENDROCHRONOLOGY , *MOUNTAIN forests , *TREE height , *MULTIPLE correspondence analysis (Statistics) , *FIR - Abstract
The introduction of foreign tree species to new areas facilitates an increase in species biodiversity and possibilities for growth of tree stands. Many years of research related to survival rate, basic growth features and evaluation of a sensitivity to climatic conditions of a new habitat is necessary to achieve a successful introduction. The paper presents the results of the research on the adaptation of grand fir to the climatic conditions in the provenance trial located in the lower montane forest belt. The dendroclimatic research has concerned the offsprings of 7 grand fir provenances originated from North America. A total of 24 trees from each provenance were selected and two cores from each tree were taken. Principal component analysis of tree-ring widths was used to classify the provenances. The climate elements described by PC1 and PC2 were identified on the basis of bootstrap correlation function. Survival rate, height and diameter at breast height of trees were also analysed. The features of the studied provenances showed significant differences. The variation of the inter-provenance survival rate and the increase in tree height of particular provenances were determined principally by the genotype. Grand firs trees from Region I exhibited superior survival rates and better dynamic increases in tree height. The variability of these two features had the character of clinal variation because they primarily depended on the elevation and the latitude of the maternal tree stands. Two groups of provenances which were connected with the regions of their natural distribution were characterized on the basis of the features of the short-term rhythm of the radial increments. The provenances of two specific groups revealed different sensitivity to temperature, rainfall, humidity and sunshine. The greatest effect on the variation of radial increments had been produced by the moisture and pluvial factors whilst the solar factor had produced the least effect on it. The air temperature made also a relatively high contribution to their radial increments. Grand fir trees from the Salmon River provenance in British Columbia provided the best trees from the cultivation point of view. The provenances from Vancouver Island and the western slope of the Cascadian Mountains in Washington State have been regarded as the best for introducing and acclimatising to the conditions of the Carpathian Mts. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
46. 'Civil skepticism' and the social construction of knowledge: A case in dendroclimatology.
- Author
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Ramírez-i-Ollé, Meritxell
- Subjects
DENDROCLIMATOLOGY ,EXTERNALIZING behavior ,SKEPTICISM ,TRUST ,SOCIAL constructionism - Abstract
Early Science and Technology Studies (STS) scholars recognized that the social construction of knowledge depends on skepticism's parasitic relationship to background expectations and trust. Subsequent generations have paid less empirical attention to skepticism in science and its relationship with trust. I seek to rehabilitate skepticism in STS – particularly, Merton's view of skepticism as a scientific norm sustained by trust among status peers – with a study of what I call 'civil skepticism'. The empirical grounding is a case in contemporary dendroclimatology and the development of a method ('Blue Intensity') for generating knowledge about climate change from trees. I present a sequence of four instances of civil skepticism involved in making Blue Intensity more resistant to critique, and hence credible (in laboratory experiments, workshops, conferences, and peer-review of articles). These skeptical interactions depended upon maintaining communal notions of civility among an increasingly extended network of mutually trusted peers through a variety of means: by making Blue Intensity complementary to existing methods used to study a diverse natural world (tree-ring patterns) and by contributing to a shared professional goal (the study of global climate change). I conclude with a sociological theory about the role of civil skepticism in constituting knowledge-claims of greater generality and relevance. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
47. Pinus halepensis is more drought tolerant and more resistant to extreme events than Pinus nigra at a sub-Mediterranean flysch site.
- Author
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Jevšenak, Jernej and Saražin, Jaša
- Abstract
Key message: Compared to Pinus nigra, Pinus halepensis exhibited higher growth rate and drought tolerance, as well as higher resilience and resistance, making it a potential species to promote in similar sites. Due to climate change, trees are exposed to more frequent and longer periods of drought, which will inevitably change the composition of tree species in the forests of the future. To better understand the effects of site characteristics on species performance under future climate, tree species need to be compared in terms of their climate sensitivity and resilience to extreme events, giving guidelines to forest management. We therefore compared the climate–growth relationships and resilience indices of black pine (Pinus nigra) and Aleppo pine (Pinus halepensis) growing at a flysch site in the northern Adriatic coast. Compared to P. nigra, P. halepensis showed higher growth rates, lower correlations with precipitation, and higher resilience and resistance, and thus should be preferred when both species are considered for planting under similar site conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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48. Potential Trees Species of North-East India for Dendroclimatological Studies.
- Author
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Balraju, Wagmare and Tripathi, S. K.
- Subjects
TREE growth ,DENDROCLIMATOLOGY ,BIOINDICATORS ,CLIMATE change mitigation - Published
- 2023
- Full Text
- View/download PDF
49. I-BIND: International Blue intensity network development working group.
- Author
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Kaczka, Ryszard J. and Wilson, Rob
- Abstract
Blue Intensity (BI) is coming of age in dendrochronology, although some methodological challenges still need resolution. In the last 20 years, 59 papers have been published focussing mainly on climatological based studies, although BI has also been shown to be useful both for historical dating and dendroecological studies. This short paper briefly reviews the BI method development of the last two decades and introduces a new collaborative initiative called I-BIND (International Blue Intensity Network Development Working Group), which is supported by the Association of Tree-Ring Research. The main aims of I-BIND are to promote continued methodological development, communicate best practice via workshops, encourage the development of BI data networks to enhance both dendroclimatology and dendro-historical dating, and to create a rich environment in which innovative and novel initiatives can be explored and discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
50. The Impact of Local Climate Change on Radial Picea abies Growth: A Case Study in Natural Mountain Spruce Stand and Low-Lying Spruce Monoculture.
- Author
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Šagát, Vladimír, Ružek, Ivan, Šilhán, Karel, and Beracko, Pavel
- Subjects
NORWAY spruce ,SILVER fir ,SPRUCE ,CLIMATE change ,GROWING season ,RANK correlation (Statistics) ,MOUNTAIN forests - Abstract
Picea abies L. Karst is undeniably one of the most important tree species growing in Slovakia. In addition to natural mountain spruce forests, monocultures planted in lower areas are also quite common. In this article, we analyze the climate–growth response differences between these two types of spruce stands in the context of local climate change consequences. The study area representing natural mountain spruce forests is located under Osobitá Mt. (Tatra Mountains, Slovakia), while the analyzed low-lying planted monoculture is situated near Biely kríž (Malé Karpaty Mountains, Slovakia). Temporal variation of the dendroclimatological relationships was expressed by the running Spearman correlation coefficient during the observed period 1961–2018. The results showed crucial differences in the dendroclimatological relationships between the selected study areas. For the natural mountain spruce stand, consistent, weak, and positive correlations to the temperature variables were typical, with negative relationships to precipitation during the growing season. In this case, the negative impact of a recent temperature rise was limited. In contrast, the monoculture reacted to the temperature variation during the growing season with fluctuations, while in the case of precipitation, almost no dependence was found. Such incoherency may be a consequence of worsened health conditions, as well as insufficient resiliency to climate-driven stress. The importance of this paper is in its wide applicability, mainly in forestry. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
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