Influence of sampling and disturbance history on climatic sensitivity of temperature-limited conifers

Accurately capturing medium- to low-frequency trends in tree-ring data is vital to assessing climatic response and developing robust reconstructions of past climate. Non-climatic disturbance can affect growth trends in tree-ring-width (RW) series and bias climate information obtained from such records. It is important to develop suitable strategies to ensure the development of chronologies that minimize these medium- to low-frequency biases. By performing high density sampling (760 trees) over a ~40-ha natural high-elevation Norway spruce ( Picea abies) stand in the Romanian Carpathians, this study assessed the suitability of several sampling strategies for developing chronologies with an optimal climate signal for dendroclimatic purposes. There was a roughly equal probability for chronologies (40 samples each) to express a reasonable ( r = 0.3–0.5) to non-existent climate signal. While showing a strong high-frequency response, older/larger trees expressed the weakest overall temperature signal. Although random sampling yielded the most consistent climate signal in all sub-chronologies, the outcome was still sub-optimal. Alternative strategies to optimize the climate signal, including very high replication and principal components analysis, were also unable to minimize this disturbance bias and produce chronologies adequately representing climatic trends, indicating that larger scale disturbances can produce synchronous pervasive disturbance trends that affect a large part of a sampled population. The Curve Intervention Detection (CID) method, used to identify and reduce the influence of disturbance trends in the RW chronologies, considerably improved climate signal representation (from r = 0.28 before correction to r = 0.41 after correction for the full 760 sample chronology over 1909–2009) and represents a potentially important new approach for assessing disturbance impacts on RW chronologies. Blue intensity (BI) also shows promise as a climatically more sensitive variable which, unlike RW, does not appear significantly affected by disturbance. We recommend that studies utilizing RW chronologies to investigate medium- to long-term climatic trends also assess disturbance impact on those series.

Download Full-text

Tree growth across the Nepal Himalaya during the last four centuries

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133317714247 ◽

2017 ◽

Vol 41 (4) ◽

pp. 478-495 ◽

Cited By ~ 15

Author(s):

UK Thapa ◽

S St. George ◽

DK Kharal ◽

NP Gaire

Keyword(s):

Tree Ring ◽

Tree Growth ◽

Environmental Changes ◽

Ring Width ◽

High Elevation ◽

Forest Growth ◽

Tree Ring Width ◽

Early 19Th Century ◽

Tree Ring Data ◽

Instrumental Records

The climate of Nepal has changed rapidly over the recent decades, but most instrumental records of weather and hydrology only extend back to the 1980s. Tree rings can provide a longer perspective on recent environmental changes, and since the early 2000s, a new round of field initiatives by international researchers and Nepali scientists have more than doubled the size of the country’s tree-ring network. In this paper, we present a comprehensive analysis of the current tree-ring width network for Nepal, and use this network to estimate changes in forest growth nation-wide during the last four centuries. Ring-width chronologies in Nepal have been developed from 11 tree species, and half of the records span at least 290 years. The Nepal tree-ring width network provides a robust estimate of annual forest growth over roughly the last four centuries, but prior to this point, our mean ring-width composite fluctuates wildly due to low sample replication. Over the last four centuries, two major events are prominent in the all-Nepal composite: (i) a prolonged and widespread growth suppression during the early 1800s; and (ii) heightened growth during the most recent decade. The early 19th century decline in tree growth coincides with two major Indonesian eruptions, and suggests that short-term disturbances related to climate extremes can exert a lasting influence on the vigor of Nepal’s forests. Growth increases since AD 2000 are mainly apparent in high-elevation fir, which may be a consequence of the observed trend towards warmer temperatures, particularly during winter. This synthesis effort should be useful to establish baselines for tree-ring data in Nepal and provide a broader context to evaluate the sensitivity or behavior of this proxy in the central Himalayas.

Download Full-text

Developing a triple tree-ring constraint for tree growth and physiology in a global land surface model

10.5194/egusphere-egu21-13546 ◽

2021 ◽

Author(s):

Jonathan Barichivich ◽

Philippe Peylin ◽

Valérie Daux ◽

Camille Risi ◽

Jina Jeong ◽

...

Keyword(s):

Tree Ring ◽

Land Surface ◽

Forest Ecosystems ◽

Ring Width ◽

Land Surface Model ◽

Surface Model ◽

Growth Variability ◽

Tree Ring Data ◽

Surface Models ◽

Global Land

Gradual anthropogenic warming and parallel changes in the major global biogeochemical cycles are slowly pushing forest ecosystems into novel growing conditions, with uncertain consequences for ecosystem dynamics and climate. Short-term forest responses (i.e., years to a decade) to global change factors are relatively well understood and skilfully simulated by land surface models (LSMs). However, confidence on model projections weaken towards longer time scales and to the future, mainly because the long-term responses (i.e., decade to century) of these models remain unconstrained. This issue limits confidence on climate model projections. Annually-resolved tree-ring records, extending back to pre-industrial conditions, have the potential to constrain model responses at interannual to centennial time scales. Here, we constrain the representation of tree growth and physiology in the ORCHIDEE global land surface model using the simulated interannual variability of tree-ring width and carbon (&#916;13C) and oxygen (&#948;18O) stable isotopes in six sites in boreal and temperate Europe.&#160; The model simulates &#916;13C (r = 0.31-0.80) and &#948;18O (r = 0.36-0.74) variability better than tree-ring width variability (r < 0.55), with an overall skill similar to that of other state-of-the-art models such as MAIDENiso and LPX-Bern. These results show that growth variability is not well represented, and that the parameterization of leaf-level physiological responses to drought stress in the temperate region can be improved with tree-ring data. The representation of carbon storage and remobilization dynamics is critical to improve the realism of simulated growth variability, temporal carrying over and recovery of forest ecosystems after climate extremes. The simulated physiological response to rising CO2 over the 20th century is consistent with tree-ring data in the temperate region, despite an overestimation of seasonal drought stress and stomatal control on photosynthesis. Photosynthesis correlates directly with isotopic variability, but correlations with &#948;18O combine physiological effects and climate variability impacts on source water signatures. The integration of tree-ring data (i.e. the triple constraint: width, &#916;13C and &#948;18O) and land surface models as demonstrated here should contribute towards reducing current uncertainties in forest carbon and water cycling.

Download Full-text

Forward modelling of tree-ring width and comparison with a global network of tree-ring chronologies

Climate of the Past ◽

10.5194/cp-10-437-2014 ◽

2014 ◽

Vol 10 (2) ◽

pp. 437-449 ◽

Cited By ~ 49

Author(s):

P. Breitenmoser ◽

S. Brönnimann ◽

D. Frank

Keyword(s):

Data Assimilation ◽

Tree Ring ◽

Ring Width ◽

Global Network ◽

Threshold Temperature ◽

Tree Ring Width ◽

Data Set ◽

Observation Operator ◽

Tree Ring Data ◽

Wide Range

Abstract. We investigate relationships between climate and tree-ring data on a global scale using the process-based Vaganov–Shashkin Lite (VSL) forward model of tree-ring width formation. The VSL model requires as inputs only latitude, monthly mean temperature, and monthly accumulated precipitation. Hence, this simple, process-based model enables ring-width simulation at any location where monthly climate records exist. In this study, we analyse the growth response of simulated tree rings to monthly climate conditions obtained from the CRU TS3.1 data set back to 1901. Our key aims are (a) to assess the VSL model performance by examining the relations between simulated and observed growth at 2287 globally distributed sites, (b) indentify optimal growth parameters found during the model calibration, and (c) to evaluate the potential of the VSL model as an observation operator for data-assimilation-based reconstructions of climate from tree-ring width. The assessment of the growth-onset threshold temperature of approximately 4–6 °C for most sites and species using a Bayesian estimation approach complements other studies on the lower temperature limits where plant growth may be sustained. Our results suggest that the VSL model skilfully simulates site level tree-ring series in response to climate forcing for a wide range of environmental conditions and species. Spatial aggregation of the tree-ring chronologies to reduce non-climatic noise at the site level yielded notable improvements in the coherence between modelled and actual growth. The resulting distinct and coherent patterns of significant relationships between the aggregated and simulated series further demonstrate the VSL model's ability to skilfully capture the climatic signal contained in tree-ring series. Finally, we propose that the VSL model can be used as an observation operator in data assimilation approaches to reconstruct past climate.

Download Full-text

Bristlecone pine tree rings and volcanic eruptions over the last 5000 yr

Quaternary Research ◽

10.1016/j.yqres.2006.07.004 ◽

2007 ◽

Vol 67 (1) ◽

pp. 57-68 ◽

Cited By ~ 116

Author(s):

Matthew W. Salzer ◽

Malcolm K. Hughes

Keyword(s):

Tree Ring ◽

Ice Core ◽

Ring Width ◽

Volcanic Eruptions ◽

Pine Tree ◽

Tree Ring Data ◽

Pinus Longaeva ◽

Bristlecone Pine ◽

Ice Core Record ◽

Pinus Aristata

AbstractMany years of low growth identified in a western USA regional chronology of upper forest border bristlecone pine (Pinus longaeva and Pinus aristata) over the last 5000 yr coincide with known large explosive volcanic eruptions and/or ice core signals of past eruptions. Over the last millennium the agreement between the tree-ring data and volcano/ice-core data is high: years of ring-width minima can be matched with known volcanic eruptions or ice-core volcanic signals in 86% of cases. In previous millennia, while there is substantial concurrence, the agreement decreases with increasing antiquity. Many of the bristlecone pine ring-width minima occurred at the same time as ring-width minima in high latitude trees from northwestern Siberia and/or northern Finland over the past 4000–5000 yr, suggesting climatically-effective events of at least hemispheric scale. In contrast with the ice-core records, the agreement between widely separated tree-ring records does not decrease with increasing antiquity. These data suggest specific intervals when the climate system was or was not particularly sensitive enough to volcanic forcing to affect the trees, and they augment the ice core record in a number of ways: by providing confirmation from an alternative proxy record for volcanic signals, by suggesting alternative dates for eruptions, and by adding to the list of years when volcanic events of global significance were likely, including the mid-2nd-millennium BC eruption of Thera.

Download Full-text

Multiproxy records of climate variability for Kamchatka for the past 400 years

Climate of the Past ◽

10.5194/cp-3-119-2007 ◽

2007 ◽

Vol 3 (1) ◽

pp. 119-128 ◽

Cited By ~ 36

Author(s):

O. Solomina ◽

G. Wiles ◽

T. Shiraiwa ◽

R. D'Arrigo

Keyword(s):

Climate Variability ◽

Tree Ring ◽

Ice Core ◽

Ring Width ◽

Summer Temperature ◽

Positive Anomaly ◽

Temperature Decrease ◽

Positive Mass ◽

The Past ◽

Tree Ring Data

Abstract. Tree ring, ice core and glacial geologic histories for the past several centuries offer an opportunity to characterize climate variability and to identify the key climate parameters forcing glacier expansion in Kamchatka over the past 400 years. A newly developed larch ring-width chronology (AD 1632–2004) is presented that is sensitive to past summer temperature variability. Individual low growth years in the larch record are associated with several known and proposed volcanic events from the Northern Hemisphere. The comparison of ring width minima and those of Melt Feature Index of Ushkovsky ice core helps confirm a 1–3 year dating accuracy~for this ice core series over the late 18th to 20th centuries. Decadal variations of low summer temperatures (tree-ring record) and high annual precipitation (ice core record) are broadly consistent with intervals of positive mass balances measured and estimated at several glaciers in 20th century, and with moraine building. According to the tree-ring data the 1860s–1880s were the longest coldest interval in the last 350 years. The latest part of this period (1880s) coincided with the positive anomaly in accumulation. This coincidence led to a positive mass balance, which is most likely responsible for glacier advances and moraine deposition of the end of 19th-early 20th centuries. As well as in some other high latitude regions (Spitsbergen, Polar Urals, Franz Jozef Land etc.) in Kamchatka these advances marked the last millennium glacial maximum. In full agreement with subsequent summer warming trend, inferred both from instrumental and tree ring data, glacier advances since 1880s have been less extensive. The late 18th century glacier expansion coincides with the inferred summer temperature decrease recorded by the ring width chronology. However, both the advance and the summer temperature decrease were less prominent that in the end of 19th century. Comparisons of the glacier history in Kamchatka with records from Alaska and the Canadian Rockies suggests broadly consistent intervals of glacier expansion and inferred summer cooling during solar irradiance minima.

Download Full-text

Independent Aridity and Drought Pieces of Evidence Based on Meteorological Data and Tree Ring Data in Southeast Banat, Vojvodina, Serbia

Atmosphere ◽

10.3390/atmos10100586 ◽

2019 ◽

Vol 10 (10) ◽

pp. 586 ◽

Cited By ~ 1

Author(s):

Milivoj B. Gavrilov ◽

Wenling An ◽

Chenxi Xu ◽

Milica G. Radaković ◽

Qingzhen Hao ◽

...

Keyword(s):

Tree Ring ◽

Air Temperature ◽

Meteorological Data ◽

Ring Width ◽

Surface Air Temperature ◽

Aridity Index ◽

Precipitation Trend ◽

Positive Temperature ◽

Tree Ring Width ◽

Tree Ring Data

In this study, aridity data and tree ring data were collected in Northern Serbia, in Southeast (SE) Banat, a subregion within Vojvodina, and Vojvodina at large. They were each investigated independently. The De Martonne Aridity Index and the Forestry Aridity Index are derived from examining the relationship between precipitation and surface air temperature data sets sourced from seven meteorological stations in SE Banat, and from 10 meteorological stations located in Vojvodina as a whole. Vojvodina is a large territory and used as the control area, for the period 1949–2017. The Palmer Drought Severity Index was derived for the period 1927–2016, for both SE Banat and the totality of Vojvodina. The results of the Tree Ring Width Index were obtained from samples collected in or around the villages of Vlajkovac and Šušara, both located in SE Banat, for the period 1927–2017. These tree ring records were compared with three previous aridity and drought indices, and the meteorological data on the surface air temperature and the precipitation, with the objective being to evaluate the response of tree growth to climate dynamics in the SE Banat subregion. It was noted that the significant positive temperature trends recorded in both areas were too insufficient to trigger any trends in aridity or the Tree Ring Width Index, as neither displayed any change. Instead, it appears that these climatic parameters only changed in response to the precipitation trend, which remained unchanged during the investigated period, rather than in response to the temperature trend. It appears that the forest vegetation in the investigated areas was not affected significantly by climate change in response to the dominant temperature increase.

Download Full-text

Comparing selected fire regime condition class (FRCC) and LANDFIRE vegetation model results with tree-ring data

International Journal of Wildland Fire ◽

10.1071/wf08001 ◽

2010 ◽

Vol 19 (1) ◽

pp. 1 ◽

Cited By ~ 16

Author(s):

Tyson L. Swetnam ◽

Peter M. Brown

Keyword(s):

Tree Ring ◽

Ponderosa Pine ◽

Fire Regime ◽

Reference Conditions ◽

Low Frequency ◽

Fire Regimes ◽

Vegetation Types ◽

Tree Ring Data ◽

Map Data ◽

Fire Regime Condition Class

Fire Regime Condition Class (FRCC) has been developed as a nationally consistent interagency method in the US to assess degree of departure between historical and current fire regimes and vegetation structural conditions across differing vegetation types. Historical and existing vegetation map data also are being developed for the nationwide LANDFIRE project to aid in FRCC assessments. Here, we compare selected FRCC and LANDFIRE vegetation characteristics derived from simulation modeling with similar characteristics reconstructed from tree-ring data collected from 11 forested sites in Utah. Reconstructed reference conditions based on trees present in 1880 compared with reference conditions modeled by the Vegetation Dynamics Development Tool for individual Biophysical Settings (BpS) used in FRCC and LANDFIRE assessments showed significance relationships for ponderosa pine, aspen, and mixed-conifer BpS but not for spruce–fir, piñon–juniper, or lodgepole pine BpS. LANDFIRE map data were found to be ~58% accurate for BpS and ~60% accurate for existing vegetation types. Results suggest that limited sampling of age-to-size relationships by different species may be needed to help refine reference condition definitions used in FRCC assessments, and that more empirical data are needed to better parameterize FRCC vegetation models in especially low-frequency fire types.

Download Full-text

Weakening climatic signal since mid-20th century in European larch tree-ring chronologies at different altitudes from the Adamello-Presanella Massif (Italian Alps)

Quaternary Research ◽

10.1016/j.yqres.2012.01.004 ◽

2012 ◽

Vol 77 (3) ◽

pp. 344-354 ◽

Cited By ~ 23

Author(s):

Anna Coppola ◽

Giovanni Leonelli ◽

Maria Cristina Salvatore ◽

Manuela Pelfini ◽

Carlo Baroni

Keyword(s):

Tree Ring ◽

Function Analysis ◽

Ring Width ◽

Negative Influence ◽

Summer Temperature ◽

Central Alps ◽

European Larch ◽

Climatic Signal ◽

Temperature Signal ◽

Over Time

Tree rings from temperature-limited environments are highly sensitive climate proxies, widely used to reconstruct past climate parameters for periods prior to the availability of instrumental data and to analyse the effect of recent global warming on tree growth. An analysis of the climatic signal in five high-elevation tree-ring width chronologies of European larch (Larix decidua Mill.) from the tops of five different glacial valleys in the Italian Central Alps revealed that they contain a strong summer-temperature signal and that tree-ring growth is especially influenced by June temperatures. However, a moving correlation function analysis revealed a recent loss of the June temperature signal in the tree-ring chronologies. This signal reduction primarily involves the two lowest-altitude chronologies. It is probable that the observed increasing importance of late-summer temperature for tree-ring growth over the past 50 yr is an effect of the lengthening growing season and of the variations in the climate/tree-ring relationship over time. All the chronologies considered, especially those at the highest altitudes, show an increasing negative influence of June precipitation on tree-ring growth. The climatic signal recorded in tree-ring chronologies from the Italian Central Alps varies over time and is also differentially influenced by climatic parameters according to site elevation.

Download Full-text

Low-frequency noise inδ13C andδ18O tree ring data: A case study ofPinus uncinatain the Spanish Pyrenees

Global Biogeochemical Cycles ◽

10.1029/2010gb003772 ◽

2010 ◽

Vol 24 (4) ◽

pp. n/a-n/a ◽

Cited By ~ 67

Author(s):

Jan Esper ◽

David C. Frank ◽

Giovanna Battipaglia ◽

Ulf Büntgen ◽

Christopher Holert ◽

...

Keyword(s):

Tree Ring ◽

Low Frequency ◽

Frequency Noise ◽

Low Frequency Noise ◽

Tree Ring Data ◽

Spanish Pyrenees

Download Full-text

Recent growth of conifer species of western North America: assessing spatial patterns of radial growth trends

Canadian Journal of Forest Research ◽

10.1139/x00-191 ◽

2001 ◽

Vol 31 (3) ◽

pp. 526-538 ◽

Cited By ~ 31

Author(s):

Donald McKenzie ◽

Amy E Hessl ◽

David L Peterson

Keyword(s):

Spatial Patterns ◽

High Latitude ◽

Low Frequency ◽

High Elevation ◽

Growth Patterns ◽

Conifer Species ◽

Growth Trend ◽

Growth Trends ◽

Low Frequency Variability ◽

Tree Ring Data

We explored spatial patterns of low-frequency variability in radial tree growth among western North American conifer species and identified predictors of the variability in these patterns. Using 185 sites from the International Tree-Ring Data Bank, each of which contained 1060 raw ring-width series, we rebuilt two chronologies for each site, using two conservative methods designed to retain any low-frequency variability associated with recent environmental change. We used factor analysis to identify regional low-frequency patterns in site chronologies and estimated the slope of the growth trend since 1850 at each site from a combination of linear regression and time-series techniques. This slope was the response variable in a regression-tree model to predict the effects of environmental gradients and species-level differences on growth trends. Growth patterns at 27 sites from the American Southwest were consistent with quasi-periodic patterns of drought. Either 12 or 32 of the 185 sites demonstrated patterns of increasing growth between 1850 and 1980 A.D., depending on the standardization technique used. Pronounced growth increases were associated with high-elevation sites (above 3000 m) and high-latitude sites in maritime climates. Future research focused on these high-elevation and high-latitude sites should address the precise mechanisms responsible for increased 20th century growth.

Download Full-text