Pine Chronology Research Articles

Identifying and Separating Pandora Moth Outbreaks and Climate from A 1500-Year Ponderosa Pine Chronology from Central Oregon

Abstract We reconstruct pandora moth (Coloradia pandora Blake) outbreaks and climate from a 1572-year (435–2006 CE) ponderosa pine (Pinus ponderosa Dougl. ex Laws.) chronology from a lava flow in central Oregon. We took samples from 128 living trees and remnant logs and crossdated the samples using skeleton plots and COFECHA for quality control. After cutting out and removing those time periods from the chronology during which insects become the main limiting factor to growth, we examine the response of tree rings to climate. Evidence of species longevity (up to 877 years), presence of periodic pandora moth defoliations (13 total), and a significant relationship with the Palmer Drought Severity Index were observed (R2 = 0.34, p < 0.001). Suppressions related to pandora moth outbreaks were recorded back to 618 CE, with a mean return interval of 104 years. Previous-fall to current-spring PDSI was reconstructed over 1376 years (630–2006 CE), where the most prolonged drought periods were 1136–1166 CE and the ...

A 211‐year growing season temperature reconstruction using tree‐ring width in Zhangguangcai Mountains, Northeast China: linkages to the Pacific and Atlantic Oceans

ABSTRACTNortheast China is one of the most vulnerable areas to climate change in high latitude regions of the Northern Hemisphere. The past temperature variations are critical to reveal the driving mechanism of climate change and to reduce the uncertainty in predicting future climates. Pre‐instrument climatic variability is poorly understood, because of the scarcity of centuries‐long climatic data. Here, we present a 211‐year (1803–2013) growing season (May–July) temperature reconstruction based on tree‐ring width chronology of Korean pine (Pinus koraiensis) from Zhangguangcai Mountains in Northeast China. The reconstruction accounted for 41.3% of the temperature variance during the calibration period from 1959 to 2013. The temperature reconstruction was similar to other nearby temperature reconstructions and correlated well spatially to gridded land and ocean surface temperature data. We identified four major cold periods (1839–1846, 1884–1901, 1906–1908 and 1941–1958) and three major warm periods (1855–1880, 1918–1932 and 1998–2013) in the past 211 years. The multi‐taper method spectral analysis revealed significant cycles at 48.8, 11.5, 8.9, 3.9, 3.5 and 2–3 years, which might be associated with global climate oscillations and land‐sea thermal contrasts, such as the sea surface temperatures, El Niño‐Southern Oscillation, Atlantic Multidecadal Oscillation and solar activity.

Altitudinal treeline dynamics of Himalayan pine in western Himalaya, India

The instrumental weather records from the western Himalayan region for the past century show an increase in annual mean atmospheric temperature with winters warming at a faster rate. The vegetation of the upper ecotonal zones, already on the climatic threshold is sensitive to any such change in climate variable most limiting the growth. To investigate the impact of climate change on treeline dynamics of Himalayan pine (Pinus wallichiana A. B. Jackson), we investigated its recruitment pattern in 12 treeline sites of different ecological settings widely distributed in monsoon and monsoon-shadow zones in the western Himalaya, India. The study explicitly revealed that Himalayan pine treeline has shifted towards the upper elevation in the investigated sites, but with varying rate (11–54 m/10 yrs) largely due to site-specific microclimatic and biotic factors. Tree-ring-width chronologies of Himalayan pine prepared from two upper forest border sites, one each in monsoon and monsoon-shadow zone, respectively revealed that winter and early spring season mean temperature has direct relationship with the radial growth of trees. This indicates that the photosynthetic assimilates during winter and early spring seasons significantly influence the ensuing year's tree growth. The sensitivity of Himalayan pine to climate change revealed in this study indicates that the projected climate change under the background influence of greenhouse gases could have serious implications on biodiversity of upper elevations in the western Himalaya.

A 414-year tree-ring-based April–July minimum temperature reconstruction and its implications for the extreme climate events, northeast China

Abstract. A ring-width series was used as a proxy to reconstruct the past 414-year record of April–July minimum temperature at Laobai Mountain, northeast China. The chronology was built using standard tree-ring procedures for providing comparable information in this area while preserving low-frequency signals. By analyzing the relationship between the tree-ring chronology of Korean pine (Pinus koraiensis) and meteorological data, we found that the standard chronology was significantly correlated with the April–July minimum temperature (r = 0.757, p &lt; 0.01). Therefore, the April–July minimum temperature since 1600 (more than six trees, but the expressed population signal (EPS) is greater than 0.85 since 1660) was reconstructed by this tree-ring series. The reconstruction equation accounted for 57.3 % of temperature variation, and it was proved reliable by testing with several methods (e.g., sign test, product mean test, reduction of the error, and coefficient of efficiency). Reconstructed April–July minimum temperature on Laobai Mountain showed six major cold periods (1605–1616, 1645–1677, 1684–1691, 1911–1924, 1930–1942, and 1951–1969) and seven major warm periods (1767–1785, 1787–1793, 1795–1807, 1819–1826, 1838–1848, 1856–1873, and 1991–2008) during the past 414 years. The reconstructed low-temperature periods in the 17th and early 18th century were consistent with the Little Ice Age (LIA) in the Northern Hemisphere, and the rate of warming in the 19th century was significantly slower than that in the late 20th century. In addition, the reconstructed series was fairly consistent with the historical and natural disaster records of extreme climate events (e.g., cold damage and frost disaster) in this area. This temperature record provides new evidence of past climate variability, and can be used to predict the climate trend in the future in northeast China.

Tree-ring Dating of The Palsangjeon Wooden Pagoda at The Beopjusa Temple in Boeun, South Korea

The Palsangjeon Pagoda is a five-story wooden building in the Beopjusa Temple area in the Songnisan national park in Chungcheongbuk-do, Korea. According to historical records, it was constructed in either AD 1605 or AD 1626. To specify the construction year more precisely, we took 41 wood samples for tree-ring analysis during repair actions in 2013; 28 from red pine (Pinus densiflora S. et Z.), 12 from oak (Quercus spp.), and 1 from fir (Abies spp.). The tree-ring boundaries became clearly visible by smoothing their cross-sectional surface and the tree-ring widths were measured under a stereo microscope. All tree-ring series were compared with each other to establish mean chronologies, which we then compared with local master chronologies established using tree rings collected from wooden elements of the Daeungjeon Hall which is the main building in the Beopjusa Temple area. As a result, it was verified that the red pines were felled in AD 1624 and in AD 1851. Moreover, it was verified that the oaks were also felled in AD 1624 based on cross-dating with the red pine chronology. We concluded that the Palsangjeon Wooden Pagoda was constructed in AD 1626, as mentioned in the historical record (Daeungdaekwangmyeongjeonbulsangki, 1630) and the letters on a purlin on the 4th story, using oak and red pine felled in AD 1624 and repaired later on using red pine felled in AD 1851.

Dendrochronological analysis of 19 Norwegian grain chests

Nineteen Norwegian grain chests made of Scots pine (Pinus sylvestris L.) were analyzed by measuring tree-ring widths on photographs and scanned pictures. Seventeen of the chests were successfully dated by dendrochronology. Two of the dates are corrections of an earlier dating; the ages of these two chests were verified by radiocarbon dating. The grain chests were expected to be medieval, but four, all without carvings, proved to be post-medieval. The mean curve constructed from the dated chests matches all regional Scots pine chronologies in central and southern Norway and several from southern Sweden. All the chests were probably constructed in central Norway. Originally only sixteen chests were known, but several new ones were discovered in the course of this project.

WHAT DETERMINES THE WIDTH OF ANNUAL TREE-RINGS IN THE CENTRAL PART OF EAST-EUROPEAN PLAIN?

No tree-ring chronologies were reported so far in the International Tree Ring Data Bank for the central part of the East-European Plain. This absence is traditionally explained by the lack of motivation for tree-ring research in this area. Indeed, due to the intense anthropogenic press the old trees are rare in this region and the climatic signal embedded in the ring width is not strong and is always complex. In this study we present the new tree-ring network of 9 ring width chronologies of pine ( Pinus sylvestris ) up to 297 years long in a large region of about 450 km in diameter in the Central Russia (54–57N, 33–40E) and analyze their climatic response. Tree ring growth in the region is controlled by both temperature and precipitation of vegetation period, and all the analyzed chronologies have signifi cant correlation with summer PDSI values (with coeffi cients up to r ≤0.4). All of them were sampled after the year 2010 when a severe summer drought spread over the European part ofRussia. This allowed spatial analysis of 2010 year annual ring (and rings related to the years of other known severe droughts of 20th century) in the context of drought impact on tree growth. This study is a starting point for constructing large tree ring network for further investigation of severity and spatial distribution of droughts in European Russia in the past.

Climatic signal in tree‐ring width chronologies of conifers in European Russia

ABSTRACTAlthough European part of Russia is the largest forest‐covered part of Europe, dendroclimatic data for high‐resolution climate reconstructions are still scarce in this region. Climatic response of 62 tree‐ring width chronologies of pine (Pinus sylvestris), spruce (Picea abies, Picea obovata) and larch (Larix sibirica) was analysed over a large area in the northern and central parts of European Russia (54–70°N, 29–57°E). The use of several climatic archives including the data from meteorological stations and gridded datasets allowed identifying the most important climatic parameters impacting the radial growth of conifers in the study region. Our results showed that all conifers growing to the north of 60°N react positively to summer temperature. To the south, at the latitude of 54–56°N, the signal is changing and the ring width depends on the combination of two parameters – warmth and humidity (precipitation, Palmer Drought Severity Index, soil moisture). These findings are in correspondence with analogous studies from nearby regions (Europe and Fennoscandia) and large‐scale studies for the whole Northern Hemisphere. Although three genera of conifers were studied, pine is much better represented in the analysed network, and the results for spruce and larch have to be confirmed in further studies. The negative correlation of the spruce‐ring width with the temperature of previous growing season has been defined for 16 of 17 studied chronologies.

Recent advances in long-term climate and moisture reconstructions from the Baltic region: Exploring the potential for a new multi-millennial tree-ring chronology

This study presents the first results from an ongoing initiative to develop a multi-millennial Baltic tree-ring width (TRW) chronology consisting of 12 floating records from subfossil Scots pines (Pinus sylvestris L.) extracted from three Lithuanian peat-mining areas. The floating series have been complemented with absolutely dated TRW chronologies which were obtained from living trees growing in unmanaged and unexploited peatland areas adjacent to each of the above study sites. The subfossil material has been dated by radiocarbon and shows a temporal spread over the last 6000 years, with assemblages of trees during the Holocene Thermal Maximum (HTM; 8000-4000 BP) and the onset of the Medieval Warm Period (MWP, AD 900–1350). Annual tree growth and sample replication of peatland pines reflect moisture variations and long-term climate variability. The importance of extending the TRW chronologies should not therefore be underestimated as (1) climate records of comparable length and resolution do not exist for the Baltic region, but also as (2) a result of a widespread lack of detailed moisture proxies spanning several millennia. Our data clearly show that a 6000-yr, continuous pine chronology from the Baltic region is a realistic objective, and would doubtlessly fill a major geographic gap in an ecologically sensitive region located at the interface between the temperate and boreal vegetation zones.

Late Holocene pinewoods persistence in the Gredos Mountains (central Spain) inferred from extensive megafossil evidence

Macro- and megafossil studies are of great value in palaeoecology because such evidence is spatially precise, directly radiocarbon dated, and usually taxon-specific. Here, we present new macro- and megafossil data from ten sites from the Gredos Mountains, central Iberian Peninsula, that suggest persistent forest cover through the late Holocene, with a widespread belt of pinewoods in the highlands of the Central Iberian Mountains. Well-preserved pine cones found at several sites revealed that both Pinus sylvestris and Pinus nigra were present in the area during the middle and late Holocene at locations of important biogeographical interest. The P. sylvestris forests represent one of the southernmost locations of its entire range. P. nigra was not known to have occurred in central Spain during the Holocene; it was found at the westernmost edge of its range in siliceous soils, a rare environment compared with the rest of its distribution. Finally, we explored the potential for obtaining a long pine chronology from central Iberia using tree-ring measurements and radiocarbon dating of pine subfossil logs.

Reconstructing mass balance of Garabashi Glacier (1800–2005) using dendrochronological data

Выполнена первая реконструкции баланса массы ледника Гарабаши по дендрохронологическим данным с 1800 по 2005 г. Лучше всего модель воспроизводит изменчивость годового баланса ледника при использовании хронологий по ширине годичных колец и по максимальной плотности поздней древесины. Изучен вклад каждой древесно-кольцевой хронологии в модель и её климатический отклик. Установлена высокая согласованность реконструкции баланса массы ледника по дендрохронологическим данным с реконструкциями, полученными ранее по метеорологическим рядам.

The 443-Year Tree-Ring Chronology for the Scots Pine from Upper Silesia (Poland) as A Dating Tool and Climate Proxy

An annually resolved and absolutely dated ring-width chronology spanning 443 years has been constructed using the historical and living-tree Scots pine samples from the Upper Silesia, south of Poland. The constructed regional chronology, based on six object chronologies, covers the period of 1568-2010. It is composed of 178 wood samples with the mean correlation of 0.51, mean series length of 104 years and mean EPS of 0.85. In total, 65 extreme years were distinguished. Their inde-pendent verification, based on the historical and meteorological data, showed significant correlation with the exceptionally cold/mild winters as well as severe droughts. The comparison of the extreme years with the other Polish pine chronologies showed similarities in the years with the anomalous winter conditions. Some extreme years can be associated with the exceptional pluvial conditions; these years are common in the Central European hydroclimatic tree-ring records. The construction of this regional pine chronology enables for the absolute dating of many architectural monuments from investigated region. The application of the new chronology for the dating of local wood can support interpretations of changes in the environment of the Upper Silesian region. In the future it can also be used as the basis for climate reconstruction.

On the hidden significance of differing micro-sites on tree-ring based climate reconstructions

Tree-ring chronologies are commonly extended back in time by combining samples from living trees with relict material preserved in man-made structures or natural archives (e.g. lakes). Although spatially close, these natural archives and living-tree-sites often comprise different micro-climates. Inhomogeneous growth conditions among these habitats, which may yield offsets in growth-rates, require caution in data processing. Here we assess species-specific growth dynamics in two micro-habitats and their potential effects on long chronologies by combining tree-ring data from different living-tree-sites with an “artificial” subfossil dataset. Well replicated (n &gt; 80) Norway spruce ( (L.) Karst.) and Scots pine ( L.) chronologies from northern Fennoscandia, sampled directly at the lakeshore (wet) and several meters beyond the lakeshore (dry) reveal high coherence of the variance between micro-sites ( = 0.59,  = 0.68). Significant differences of the Regional Curves (RC) indicate faster growth of both species at the drier site though. Growth differences are more pronounced between the spruce micro-sites. The combination of recent dry and wet spruce data with artificial relict data results in two long chronologies covering the last 800 years with substantially different trends, although they consist of the same relict material and the micro-site chronologies correlate significantly over the past two centuries. The combination of spruce samples from dry inland micro-sites with subfossil samples originating from the wet lake shore can result in an underestimation of past temperatures prior to the 19th century. Such effects, hidden in the composition of long chronologies (living trees + subfossil samples) can bias long-term trends in climate reconstructions.Picea abiesPinus sylvestrisrsprucerpine

An Annual Streamflow Reconstruction of the Red River, Kentucky Using a White Pine (Pinus Strobus) Chronology

Using tree ring data (dendrochronology) a reconstruction of the historical annual stream flow of the Red River Basin of Kentucky was performed. Tree ring widths provide a surrogate record of the past climate and hence stream flow of a particular area, with thicker rings corresponding to wetter periods and thinner rings corresponding to drier conditions. This type of research is common in river basins across the western USA which are prone to serious droughts and flooding on annual and decadal scales. However, little research has been conducted in this manner in the eastern USA, Kentucky in particular, despite the potential for intermittent dry and wet periods over time. The use of the Daniel Boone National Forest is the focus of this study due to the well documented past flooding and drought events of the Red River during the 20th Century. The technique provided a reconstructed record from 1713 up to the end of the observed period in 1999. The results show that there has been a decrease in the number and frequency of prolonged wet and dry periods, although there has been an increase in the extreme wet and dry conditions during the later observed record which suggests a shift in the hydroclimatological regime of the river basin.

Using adjusted Blue Intensity data to attain high-quality summer temperature information: A case study from Central Scandinavia

The inexpensive Blue Intensity proxy has been considered a complement or surrogate to maximum latewood density (MXD), but is associated with biases from differential staining between sapwood and heartwood and also between deadwood samples and living-wood samples that compromise centennial-scale information. Here, we show that, with some minor adjustments, ΔBlue Intensity (ΔBI) is comparable with MXD or ΔDensity (Δ = the difference or contrast between latewood and earlywood density) in dendroclimatological reconstructions of summer temperatures in the Central Scandinavian region, using Pinus sylvestris L. (Scots pine), on annual and multi-centennial timescales. By using ΔBI, this bias is significantly reduced, but the contrast between earlywood and latewood in BI is altered with degree of staining, while for density it is not. Darker deadwood samples have a reduced contrast compared with the lighter living-wood samples that make ΔBI and ΔDensity chronologies diverge. Here, we quantify this behaviour in BI and offer an adjustment that can reduce this bias. The adjustment can be derived on independent samples, so in future work on BI, parallel density measurements are not necessary. We apply this methodology to two Central Scandinavian Scots pine chronologies that averaged into a composite is able to reconstruct summer temperatures with an explained variance in excess of 60% in each verification period using a split sample calibration verification procedure. Although the amount of data used to derive this contrast adjustment produces desirable results, more tests are needed to confirm its performance, and we suggest that future work on the BI proxy should aim for a small subset of parallel BI and density measurements while the bulk of the data is only measured with the BI technique. This is to ensure that the adjustment is continuously updated with new data and that the conclusions derived here are robust.

Early summer temperatures reconstructed from black pine (Pinus nigra Arnold) tree-ring widths from Albania

The first regional chronology of black pine ( Pinus nigra Arnold) from Albania, its response to climate and a 428-year long reconstruction of June–July temperatures for the 1583–2010 period are presented. Samples were collected at five locations from the north to the south of Albania. We constructed a 552-year long Pinus nigra chronology with sufficient sample depth for potential climate reconstruction from 1583 to 2010 (428 years). Response to precipitation was significant only for July of the current year (0.23), while a clear temperature response to the May–August period was identified, with July having by far the highest correlation (−0.47). When combined, June–July temperatures had the highest correlation of all tested combinations ( r = −0.63), explaining almost 40% of the tree-ring width variability. The test of the climate signal temporal stability using a 31-year running correlation highlighted the very stable relationship between tree-ring indices and June–July temperatures. The spatial extent of the regional Pinus nigra chronology tested, using a field correlation function, showed very high spatial correlation over a large part of the Balkan Peninsula and even southern Italy. Based on high explained variance between tree-ring indices and June–July temperatures and significant values of reduction of error (RE) and coefficient of efficiency statistics (CE; 0.62 and 0.25 in the calibration period), a linear model was developed, with June–July temperatures reconstructed for the 1583–2010 period. Our reconstruction and identified extreme years were compared with various temperature, drought and precipitation reconstructions from nearby regions, as well as data from documentary archives. We confirmed a high degree of similarity of our reconstruction with other reconstructions and documentary data.

Fennoscandia revisited: a spatially improved tree-ring reconstruction of summer temperatures for the last 900 years

Despite the spatially homogenous summer temperature pattern in Fennoscandia, there are large spreads among the many existing reconstructions, resulting in an uncertainty in the timing and amplitude of past changes. Also, there has been a general bias towards northernmost Fennoscandia. In an attempt to provide a more spatially coherent view of summer (June–August, JJA) temperature variability within the last millennium, we utilized seven density and three blue intensity Scots pine (Pinus sylvestris L.) chronologies collected from the altitudinal (Scandinavian Mountains) and latitudinal (northernmost part) treeline. To attain a JJA temperature signal as strong as possible, as well as preserving multicentury-scale variability, we used a new tree-ring parameter, where the earlywood information is removed from the maximum density and blue intensity, and a modified signal-free standardization method. Two skilful reconstructions for the period 1100–2006 CE were made, one regional reconstruction based on an average of the chronologies, and one field (gridded) reconstruction. The new reconstructions were shown to have much improved spatial representations compared to those based on data from only northern sites, thus making it more valid for the whole region. An examination of some of the forcings of JJA mean temperatures in the region shows an association with sea-surface temperature over the eastern North Atlantic, but also the subpolar and subtropical gyres. Moreover, using Superposed Epoch Analysis, a significant cooling in the year following a volcanic eruption was noted, and for the largest explosive eruptions, the effect could remain for up to 4 years. This new improved reconstruction provides a mean to reinforce our understanding of forcings on summer temperatures in the North European sector.

Climate sensitivity of Mediterranean pine growth reveals distinct east-west dipole

The European Mediterranean region is governed by a characteristic climate of summer drought that is likely to increase in duration and intensity under predicted climate change. However, large-scale network analyses investigating spatial aspects of pre-instrumental drought variability for this biogeographic zone are still scarce. In this study we introduce 54 mid- to high-elevation tree-ring width (TRW) chronologies comprising 2186 individual series from pine trees (Pinus spp.). This compilation spans a 4000-km east–west transect from Spain to Turkey, and was subjected to quality control and standardization prior to the development of site chronologies. A principal component analysis (PCA) was applied to identify spatial growth patterns during the network's common period 1862–1976, and new composite TRW chronologies were developed and investigated. The PCA reveals a common variance of 19.7% over the 54 Mediterranean pine chronologies. More interestingly, a dipole pattern in growth variability is found between the western (15% explained variance) and eastern (9.6%) sites, persisting back to 1330 AD. Pine growth on the Iberian Peninsula and Italy favours warm early growing seasons, but summer drought is most critical for ring width formation in the eastern Mediterranean region. Synoptic climate dynamics that have been in operation for the last seven centuries have been identified as the driving mechanism of a distinct east–west dipole in the growth variability of Mediterranean pines.

Continuing upward trend in Mt Read Huon pine ring widths – Temperature or divergence?

To date, no attempt has been made to assess the presence or otherwise of the “Divergence Problem” (DP) in existing multi-millennial Southern Hemisphere tree-ring chronologies. We have updated the iconic Mt Read Huon pine chronology from Tasmania, southeastern Australia, to now include the warmest decade on record, AD 2000–2010, and used the Kalman Filter (KF) to examine it for signs of divergence against four different temperature series available for the region. Ring-width growth for the past two decades is statistically unprecedented for the past 1048 years. Although we have identified a decoupling between temperature and growth in the past two decades, the relationship between some of the temperature records and growth has varied over time since the start of instrumental records. Rather than the special case of ‘divergence’, we have identified a more general time-dependence between growth and temperature over the last 100 years. This time-dependence appears particularly problematic at interdecadal time scales. Due to the time-dependent relationships, and uncertainties related to the climate data, the use of any of the individual temperature series examined here potentially complicates temperature reconstruction. Some of the uncertainty in the climate data may be associated with changing climatic conditions, such as the intensification of the sub-tropical ridge (STR) and its impact on the frequency of anticyclonic conditions over the Mt Read site. Increased growth at the site, particularly in the last decade, over and above what would be expected based on a linear temperature model alone, may be consistent with a number of hypotheses. Existing uncertainties in the climate data need to be resolved and independent physiological information obtained before a range of hypotheses for this increased growth can be effectively evaluated.

A tree-ring based drought reconstruction (AD 1760–2010) for the Loess Plateau and its possible driving mechanisms

We have developed a 272-year ring-width chronology of Chinese pine (Pinus tabulaeformis) growing in the Huanglong Mountains, North China. Climatic response analyses revealed that mean January–July Palmer drought severity index (PDSI) has positive effect on the radial growth of pine trees. Based on the relationships, the mean January–July PDSI was reconstructed for the period from 1760 to 2010. The percentage of variance in the data explained by the reconstruction was 41% during the calibration period of 1950–2010. Spatial correlation analyses between the PDSI reconstruction and gridded PDSI data show that the PDSI reconstruction captures regional drought variations over the environmentally-sensitive area linked to the East Asian summer monsoon. Relatively wet periods are identified for AD 1766–1781, 1795–1804, 1811–1821, 1838–1859, 1884–1889, 1909–1914, 1937–1977 and 2003–2008. Dry conditions prevailed during AD 1760–1765, 1782–1794, 1805–1810, 1822–1837, 1860–1883, 1890–1908, 1915–1936, 1978–2002 and 2009–now. There is a reasonable agreement with dry/wet periods previously estimated from tree-ring data of the Kongtong Mountains of the Loess Plateau. Spatial correlation analyses with sea surface temperature in the Pacific Ocean and tropical Indian Ocean indicated that the Asian summer monsoon circulations play a role in modulating drought variations in the study area whereas the effects of the Pacific Decadal Oscillation are relatively strong.