Climate signal in tree-ring chronologies in a temperate climate: A multi-species approach

Tree-ring widths (TRW) of historical and archeological wood provide crucial proxies, frequently used for high-resolution multi-millennial paleoclimate reconstructions. Former growing conditions of the utilized trees, however, are largely unknown. Potential influences of historical forest management practices on climatic information, derived from TRW variability need to be considered but have not been assessed so far. Here, we examined the suitability of TRW series from traditionally managed oak forests (Quercus spp.) for climate reconstructions. We compared the climate signal in TRW chronologies of trees originating from high forests and coppice-with-standards (CWS) forests, a silvicultural management practice widely used in Europe for most of the common era. We expected a less distinct climate control in CWS due to management-induced growth patterns, yet an improved climate-growth relationship with TRW data from conventionally managed high forests. CWS tree rings showed considerably weaker correlations with hydroclimatic variables than non-CWS trees. The greatest potential for hydroclimate reconstructions was found for a large dataset containing both CWS and non-CWS trees, randomly collected from lumber yards, resembling the randomness in sources of historical material. Our results imply that growth patterns induced by management interventions can dampen climate signals in TRW chronologies. However, their impact can be minimized in well replicated, randomly sampled regional chronologies.

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Air moisture signals in a stable oxygen isotope chronology of dwarf shrubs from the central Tibetan Plateau

Annals of Botany ◽

10.1093/aob/mcz030 ◽

2019 ◽

Vol 124 (1) ◽

pp. 53-64

Author(s):

Jakob Wernicke ◽

Georg Stark ◽

Lily Wang ◽

Jussi Grießinger ◽

Achim Bräuning

Keyword(s):

Tibetan Plateau ◽

Tree Ring ◽

Growth Ring ◽

Asian Summer Monsoon ◽

Monsoon Circulation ◽

Nam Co ◽

Climate Signal ◽

Dwarf Shrubs ◽

Central Tibetan Plateau ◽

Annual Growth Rings

Abstract Background and Aims Annually resolved biological climate proxies beyond the altitudinal and latitudinal distribution limit of trees are rare. In such regions, several studies have demonstrated that annual growth rings of dwarf shrubs are suitable proxies for palaeoclimatic investigations. In High Asia, the pioneer work of Liang et al. (Liang E, Lu X, Ren P, Li X, Zhu L, Eckstein D, 2012. Annual increments of juniper dwarf shrubs above the tree line on the central Tibetan Plateau: a useful climatic proxy. Annals of Botany109: 721–728) confirmed the suitability of shrub growth-ring chronologies for palaeoclimatic research. This study presents the first sensitivity study of an annually resolved δ18O time series inferred from Wilson juniper (Juniperus pingii var. wilsonii) from the northern shoreline of lake Nam Co (Tibetan Plateau). Methods Based on five individual dwarf shrub discs, a statistically reliable δ18O chronology covering the period 1957–2009 was achieved (expressed population signal = 0.80). Spearman’s correlation analysis between the δ18O chronology and climate variables from different sources was applied. In a first step, the suitability of various climate data was evaluated. Key Results Examinations of climate–proxy relationships revealed significant negative correlations between the δ18O shrub chronology and summer season moisture variability of the previous and current year. In particular, relative humidity of the previous and current vegetation period significantly determined the proxy variability (ρ = −0.48, P < 0.01). Furthermore, the δ18O variability of the developed shrub chronology significantly coincided with a nearby tree-ring δ18O chronology of the same genus (r = 0.62, P < 0.01). Conclusions The δ18O shrub chronology reliably recorded humidity variations in the Nam Co region. The chronology was significantly correlated with a nearby moisture-sensitive tree-ring δ18O chronology, indicating a common climate signal in the two chronologies. This climate signal was likely determined by moisture variations of the Asian summer monsoon. Local climate effects were superimposed on the supra-regional climate signature of the monsoon circulation. Opposing δ18O values between the two chronologies were interpreted as plant-physiological differences during isotopic fractionation processes.

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A lonely dot on the map: Exploring the climate signal in tree-ring density and stable isotopes of clanwilliam cedar, South Africa

Dendrochronologia ◽

10.1016/j.dendro.2021.125879 ◽

2021 ◽

Vol 69 ◽

pp. 125879

Author(s):

Tom De Mil ◽

Matthew Meko ◽

Soumaya Belmecheri ◽

Edmund February ◽

Matthew Therrell ◽

...

Keyword(s):

South Africa ◽

Stable Isotopes ◽

Tree Ring ◽

Climate Signal ◽

Ring Density

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A fistful of shells: amplifying sclerochronological and palaeoclimate signals from molluscan death assemblages

Geological Magazine ◽

10.1017/s0016756809990033 ◽

2009 ◽

Vol 146 (6) ◽

pp. 917-930 ◽

Cited By ~ 7

Author(s):

S. HELAMA ◽

J. K. NIELSEN ◽

M. MACIAS FAURIA ◽

I. VALOVIRTA

Keyword(s):

Sample Size ◽

Tree Ring ◽

Small Sample Size ◽

Low Frequency ◽

Small Sample ◽

Pearl Mussel ◽

Climate Signal ◽

Growth Variability ◽

Low Frequency Variability ◽

The Individual

AbstractA growing body of literature is using sclerochronological information to infer past climates. Sclerochronologies are based on series of skeletal growth records of molluscs that have been correctly aligned in time. Incremental series are obtained from a number of shells to assess the temporal control and improve the climate signal in the final chronology. Much of the sclerochronological theory has been adopted from tree-ring science, due to the longer tradition and more firmly established concepts of chronology construction in dendrochronology. Compared to tree-ring studies, however, sclerochronological datasets are often characterized by relatively small sample size. Here we evaluate how effectively palaeoclimatic signal can be extracted from such a suite of samples. In so doing, the influences of the very basic methods that are applied in nearly every sclerochronological study to remove the non-climatic growth variability prior to palaeoclimatic interpretations, are ranked by their capability to amplify the desired signal. The study is performed in the context of six shells that constitute a bicentennial growth record from annual shell increments of freshwater pearl mussel. It was shown that when the individual series were detrended using the models set by the mean or the median summary curves for ageing (that is, applying Regional Curve Standardization, RCS), instead of fitting the ageing mode statistically to each series, the resulting sclerochronology displayed more low-frequency variability. Consistently, the added low-frequency variability evoked higher proxy–climate correlations. These results show the particular benefit of using the RCS method to develop sclerochronologies and preserve their low-frequency variations. Moreover, calculating the ageing curve and the final chronology by median, instead of mean, resulted in an amplified low-frequency climate signal. The results help to answer a growing need to better understand the behaviour of the sclerochronological data. In addition, we discuss the pitfalls that may potentially disrupt palaeoclimate signal detection in similar sclerochronological studies. Pitfalls may arise from shell taphonomy, water chemistry, time-variant characters of biological growth trends and small sample size.

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Experiments based on blue intensity for reconstructing North Pacific temperatures along the Gulf of Alaska

Climate of the Past ◽

10.5194/cp-13-1007-2017 ◽

2017 ◽

Vol 13 (8) ◽

pp. 1007-1022 ◽

Cited By ~ 13

Author(s):

Rob Wilson ◽

Rosanne D'Arrigo ◽

Laia Andreu-Hayles ◽

Rose Oelkers ◽

Greg Wiles ◽

...

Keyword(s):

Tree Ring ◽

North Pacific ◽

Ring Width ◽

Gulf Of Alaska ◽

Climate Response ◽

Cool Period ◽

Climate Signal ◽

Latewood Density ◽

Blue Intensity

Abstract. Ring-width (RW) records from the Gulf of Alaska (GOA) have yielded a valuable long-term perspective for North Pacific changes on decadal to longer timescales in prior studies but contain a broad winter to late summer seasonal climate response. Similar to the highly climate-sensitive maximum latewood density (MXD) proxy, the blue intensity (BI) parameter has recently been shown to correlate well with year-to-year warm-season temperatures for a number of sites at northern latitudes. Since BI records are much less labour intensive and expensive to generate than MXD, such data hold great potential value for future tree-ring studies in the GOA and other regions in mid- to high latitudes. Here we explore the potential for improving tree-ring-based reconstructions using combinations of RW- and BI-related parameters (latewood BI and delta BI) from an experimental subset of samples at eight mountain hemlock (Tsuga mertensiana) sites along the GOA. This is the first study for the hemlock genus using BI data. We find that using either inverted latewood BI (LWBinv) or delta BI (DB) can improve the amount of explained temperature variance by > 10 % compared to RW alone, although the optimal target season shrinks to June–September, which may have implications for studying ocean–atmosphere variability in the region. One challenge in building these BI records is that resin extraction did not remove colour differences between the heartwood and sapwood; thus, long term trend biases, expressed as relatively warm temperatures in the 18th century, were noted when using the LWBinv data. Using DB appeared to overcome these trend biases, resulting in a reconstruction expressing 18th–19th century temperatures ca. 0.5 °C cooler than the 20th–21st centuries. This cool period agrees well with previous dendroclimatic studies and the glacial advance record in the region. Continuing BI measurement in the GOA region must focus on sampling and measuring more trees per site (> 20) and compiling more sites to overcome site-specific factors affecting climate response and using subfossil material to extend the record. Although LWBinv captures the inter-annual climate signal more strongly than DB, DB appears to better capture long-term secular trends that agree with other proxy archives in the region. Great care is needed, however, when implementing different detrending options and more experimentation is necessary to assess the utility of DB for different conifer species around the Northern Hemisphere.

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The significance of climate and solar variability on historical European grain prices

10.5194/egusphere-egu2020-11257 ◽

2020 ◽

Author(s):

Fredrik Charpentier Ljungqvist ◽

Peter Thejll ◽

Bo Christiansen ◽

Andrea Seim ◽

Claudia Hartl ◽

...

Keyword(s):

Early Modern ◽

Tree Ring ◽

Early Modern Europe ◽

Solar Forcing ◽

Time And Space ◽

Climate Signal ◽

Temperature Reconstructions ◽

Modern Europe ◽

Grain Prices

Grain was the most important food source for a majority of the population in early modern Europe (c. 1500&#8211;1800). The price level and volatility had huge societal effects: high prices tended to increase mortality, decrease fertility as well as affect overall consumption patterns. To what extent climate variability influenced the long-term grain price evolution in early modern Europe has for a long time been a matter of debate. Recent advances in high-resolution palaeoclimatology and historical climatology have made it possible to reassess the grain price&#8211;climate relationship in time and space with unprecedented detail (Esper et al. 2017). We analyse the climate signal in 56 multi-centennial long series of annual prices of barley, oat, rye, and wheat across Europe. The grain price&#8211;climate relationship in regional clusters of grain price data is analysed using both tree-ring based temperature reconstructions, documentary-based temperature reconstructions, tree-ring based drought reconstructions, and early temperature and precipitation instrumental data, considering possible different climate responses in each grain type and different seasonal targets. In addition, we systematically investigate whether, and to what extent, the imprints of variations in solar forcing, including possible lag effects, can be detected in the grain prices.We find a highly significant and persistent negative temperature&#8211;price relationship (i.e., cold = high prices and vice versa) across all of Europe and for all four grain types using both temperature reconstructions and instrumental temperature data. Excluding the Thirty Years&#8217; War (1618&#8211;1648) and the period following the French Revolution (1789), this relationship is as strong as r = &#8211;0.41 between the annual average of all the 56 included European grain price series and the reconstructed June&#8211;August temperature for the previous year. The correlations to drought and precipitation are, on the other hand, mainly insignificant and inconsistent in time and space. The evidence for the existence of the effect of solar forcing variations on early modern European grain prices is not strong, although we can detect statistically significant grain price&#8211;solar forcing relationships for certain regions. In conclusion, we find much stronger evidence than hitherto reported for long-term temperature imprints on historical grain prices in Europe, implying that temperature variability and change have been a more important factor in European economic history, even in southern Europe, than commonly acknowledged.&#160;Reference:Esper J., et al., 2017. Environmental drivers of historical grain price variations in Europe. Clim. Res. 72: 39&#8211;52.

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Exploring the climate signal in tree-ring density of Clanwilliam cedar, South Africa

10.5194/egusphere-egu2020-20692 ◽

2020 ◽

Author(s):

Valerie Trouet ◽

Tom De Mil ◽

Matthew Meko ◽

Jan Van den Bulcke

Keyword(s):

South Africa ◽

Tree Ring ◽

Southern Africa ◽

Ring Width ◽

Future Climate Change ◽

Spring Precipitation ◽

Climate Signal ◽

Climatic Signal ◽

X Ray Computed ◽

Instrumental Records

High-resolution annual precipitation and temperature proxies are largely lacking in Southern Africa, partly due to the scarcely available tree species that are suitable for dendrochronology. Clanwilliam cedar (Widdringtonia cedarbergensis) from Cape Province, South Africa, is a long-lived conifer with distinct tree rings and thus a strong dendroclimatic potential. However, the climatic signal in its tree-ring width (TRW) is weak and other tree-ring parameters such as density need to be explored to extract climatic information from this proxy. Here we investigate the climatic signal of density parameters in 17 Clanwilliam cedar samples (9 trees) collected in 1978 (Dunwiddie & LaMarche, 1980). We use a non-destructive X-ray Computed Tomography facility to develop minimum density (MIND) and maximum density (MXD) chronologies from 1900 until 1977. EPS for both density series exceeded 0.85. For the period 1930-1977 (reliable instrumental records), MIND correlates negatively with early-growing season precipitation (Oct-Nov), whereas MXD correlates negatively with end-of-season (March) temperature. The spatial correlation between MIND and spring precipitation spans the winter rainfall zone of South Africa. Clanwilliam cedar can live to be 356 years old and the current TRW chronology extends to 1564 CE. Full-length density chronologies for this long-lived species could provide a precipitation reconstruction for southern Africa, a region where historical climate observations are limited and where societal vulnerability to future climate change is high.References:Dunwiddie, P. W., & LaMarche, V. C. (1980). A climatically responsive tree-ring record from Widdringtonia cedarbergensis, Cape Province, South Africa. Nature, 286(5775), 796&#8211;797.

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Impact of Precipitation and Temperature Variability of the East Asian Summer Monsoon (EASM) on Annual Radial Increment of Selected Tree Species in Northeast China

Forests ◽

10.3390/f11101093 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1093

Author(s):

Sandra-Maria Hipler ◽

Benedikt Speicher ◽

Lars Sprengel ◽

Hans-Peter Kahle ◽

Heinrich Spiecker ◽

...

Keyword(s):

Air Temperature ◽

Tree Species ◽

Northeast China ◽

Asian Summer Monsoon ◽

Species Selection ◽

Temperate Climate ◽

Radial Increment ◽

Growth Responses ◽

Climate Signal ◽

Picea Asperata

A dendroclimatological approach was used to analyze growth responses of the tree species Pinus tabuliformis Carr., Larix gmelinii Rupr., Picea asperata Mast. and Quercus mongolica Fisch. ex Ledeb. in a region of temperate climate in Northeast China. Annual radial increment (ARI) measurements from stem cross-sections were used to identify the effects of precipitation, air temperature and standardized precipitation evapotranspiration index (SPEI) on tree growth under monsoon-related conditions. We analyzed the ARI of 144 trees from 49 forest stands and applied response function and moving correlation analysis as well as a linear mixed-effects model to detect climate signal in the tree-ring series. Analyses of climate-growth relations confirmed the influence of monsoon intensities on ARI, especially in the months of May to July of the current year. Particularly in times of a weak monsoon, the preceding autumn months significantly affect the ARI. The positive effect of precipitation in times of a strong monsoon and the negative effect of air temperature-indicating increased evapotranspiration-in times of a weak monsoon alternate. An increase in drought sensitivity of the ARI was found, especially after long dry periods. The results revealed for L. gmelinii the highest climate sensitivity, with ARI more strongly influenced by precipitation in the monsoon-related months, whereas Q. mongolica was most drought tolerant and recovered quicker after growth depression. P. asperata and P. tabuliformis were located in between. Our findings provide evidence for a strong influence of the periodically fluctuating monsoon intensities on the ARI of all investigated tree species. Our results support decision-making for forest management under anticipated climate change, especially for tree species selection, in the climate sensitive region of Northeast China.

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Assessment of combined glacier and tree-ring studies to constrain latitudinal climate forcing of Scandinavian glacier mass balances

Annals of Glaciology ◽

10.3189/172756405781812835 ◽

2005 ◽

Vol 42 ◽

pp. 303-310 ◽

Cited By ~ 7

Author(s):

Peter Jansson ◽

Hans W. Linderholm

Keyword(s):

Mass Balance ◽

Tree Ring ◽

Regional Climate ◽

Summer Temperature ◽

The Arctic ◽

Glacier Mass Balance ◽

Climate Information ◽

Climate Signal ◽

South Central ◽

Tree Ring Data

AbstractAssessing climate change and its effects on the cryosphere is important, and individual proxies are commonly used for such assessments. We have investigated the possibility of combining glacier mass balance and tree-ring data to better understand regional climate variability in Scandinavia. There are substantial differences between climate information in mass-balance and tree-ring data. Summer balance (bS) is strongly related to summer temperature, while winter balance (bW) is less readily interpreted in terms of a climate signal. Tree rings are good summer temperature proxies, but due to the complexity of tree growth factors (e.g. the effect of the previous winter’s climate) tree-ring records do not exclusively represent summer temperatures. Combining bS and tree-ring records will not likely yield additional summer climate information. The relationship of mass balance with the Arctic Oscillation is stronger than with the North Atlantic Oscillation, especially for northernmost Sweden, whereas no such correlations were found for tree-ring data. The agreement between bN records from both maritime south-central Norway and continental northernmost Sweden and tree-ring data from Jämtland, in a maritime/continental climate transition zone, suggests possibilities to combine mass-balance and tree-ring data to provide information about climate over the entire year on interannual timescales.

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Dendroclimatology of high-elevation Nothofagus pumilio forests at their northern distribution limit in the central Andes of Chile

Canadian Journal of Forest Research ◽

10.1139/x00-208 ◽

2001 ◽

Vol 31 (6) ◽

pp. 925-936 ◽

Cited By ~ 19

Author(s):

Antonio Lara ◽

Juan Carlos Aravena ◽

Ricardo Villalba ◽

Alexia Wolodarsky-Franke ◽

Brian Luckman ◽

...

Keyword(s):

Tree Ring ◽

Radial Growth ◽

Summer Precipitation ◽

Central Andes ◽

Early Summer ◽

Late Spring ◽

Tree Line ◽

Nothofagus Pumilio ◽

Precipitation Reconstruction ◽

Climate Signal

Nothofagus pumilio (Poepp et Endl.) Krasser, is a deciduous tree species that grows in Chile and adjacent Argentina between 36 and 56°S, often forming the Andean tree line. This paper presents the first eight tree-ring chronologies from N. pumilio at its northern range limit in the central Andes of Chile (3639°S) and the first precipitation reconstruction for this region. Samples were taken from upper tree-line stands (15001700 m elevation) in three study areas: Vilches, Laguna del Laja, and Conguillío. Results indicate that, at the northern sites (Vilches and Laguna del Laja), the tree-ring growth of N. pumilio is positively correlated with late-spring and early summer precipitation and that higher temperatures reduce radial growth, probably because of an increase in evapotranspiration and decrease in water availability. At the southern Conguillío study area, radial growth was negatively correlated with late-spring and early summer precipitation. The presence of volcanic activity in this latter study area, which might have masked the climate signal, did not seem to have a significant influence on radial growth. A reconstruction of NovemberDecember (summer) precipitation for the period 18371996 from N. pumilio tree-ring chronologies accounted for 37% of instrumentally recorded precipitation variance. This is the first precipitation reconstruction from N. pumilio chronologies. Only temperature and snow cover have previously been reconstructed using this species. The reconstruction indicates that the driest and wettest 25-year periods within the past 160 years are 18901914 and 19171941, respectively.

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