What Is the Carbon Origin of Early-Wood?

ABSTRACTSubstantial amounts of annual radiocarbon (14C) data have recently been produced with the purpose of increasing the time resolution of 14C records used for constructing the calibration curve and for studying the occurrence of abrupt cosmic-ray events. In this study, we investigate if it is possible to resolve sub-annual scale changes in the atmospheric 14C content by measuring radiocarbon in early-wood and late-wood fractions from Danish oak. The tree-ring samples span the period 1954–1970 CE, hereby covering the peak of the bomb pulse. A least squares test comparing the atmospheric 14C content and the new sub-annual 14C record from Danish tree rings reveals that by measuring early-wood and late-wood fractions, it may be possible to resolve sub-annual variations in past atmospheric 14C levels.

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The significance of compression wood in restoration of the leader in Pinus sihestris L. damaged by moose (Alces alces). II. Structure of growth rings in regenerating stems in relation to juvenile wood formation

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1971.020 ◽

2015 ◽

Vol 40 (2) ◽

pp. 315-340 ◽

Cited By ~ 4

Author(s):

B. A. Molski

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Compression Wood ◽

Juvenile Wood ◽

Alces Alces ◽

Wood Formation ◽

Ring Structure ◽

Growth Rings ◽

Late Wood ◽

Wood Compression

The corewood of pine ds very prone to compression wood formation, this changing the whole pattern of the tree ring structure and the siz.es of early and late wood. Compression wood always increases the formation of late wood at the expense of early wood. Tree rings with compression wood are generally wider than those without it, but there occur also tree rings wihout compression wood wider than those in which it is present, formed in the same year and in the same tree.

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Tree-Ring Analyses can be Improved by Measurement of Component Widths and Densities

The Forestry Chronicle ◽

10.5558/tfc53091-2 ◽

1977 ◽

Vol 53 (2) ◽

pp. 91-95 ◽

Cited By ~ 1

Author(s):

J. Harry G. Smith

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Tree Growth ◽

Annual Rings ◽

Sources Of Information ◽

X Ray ◽

Annual Variations ◽

Binocular Microscope ◽

Study Component ◽

Ray Methods

Measurement of component widths of annual rings by binocular microscope and of densities by X-ray methods have increased the accuracy of estimation of effects of various factors on tree growth. Sources of information and examples of uses of tree-ring analyses are discussed. Measurements of latewood and earlywood components of tree rings are used to illustrate longterm trends and annual variations about them. It is concluded that foresters should study component widths and densities of tree rings in order to learn more about manipulation of tree growth toward desired goals.

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Tracking atmospheric carbon emissions in southern Ontario, Canada using dendrochronological records

10.5194/egusphere-egu21-10031 ◽

2021 ◽

Author(s):

Michael Pisaric ◽

Carley Crann ◽

Felix Vogel

Keyword(s):

Environmental Change ◽

Tree Ring ◽

Tree Rings ◽

Fossil Fuel ◽

Cosmic Ray ◽

Proxy Data ◽

Southern Ontario ◽

Clean Air ◽

Atmospheric Sampling ◽

Instrumental Records

Records of environmental change are often temporally short, perhaps spanning a few decades.&#160; For many environmental issues impacting the world today, we have very limited observations or data concerning those changes.&#160; Therefore, we need to supplement the short observational and instrumental records of environmental change with proxy data sources.&#160; Tree-ring growth records are one type of proxy data source that can be examined at annual timescales to track changes in the environment across longer periods than afforded by relatively short observations and instrumental data records.&#160; Changes in the composition of some gases in the atmosphere, are one example of environmental change that can be elucidated using tree-ring records.&#160; Trees utilize various forms of carbon dioxide during photosynthesis, including radiocarbon (14C).&#160; Naturally, 14C in the atmosphere varies through time due to cosmic ray flux and ocean-atmosphere dynamics.&#160; The concentration of 14C also varies due to anthropogenic activities, including burning of fossil fuels, nuclear bomb testing, and the operation of nuclear power plants (NPPs).&#160; Tree rings record atmospheric 14C concentration during the growing season and are an effective tool to trace 14C in the atmosphere from a variety of sources, including NPPs.In Southern Ontario, Canada there are 15 operational CANDU reactors at three NPPs (Bruce (8), Darlington (1) and Pickering (6)).&#160; Southern Ontario is also one of the most densely populated regions of Canada and is a major source of fossil fuel derived carbon that is depleted in 14C. Monitoring of atmospheric 14C in Ontario is conducted at the&#160;Centre for Atmospheric Research Experiments, operated by Environment and Climate Change Canada (ECCC).&#160; The facility is considered a clean air site, located approximately halfway between the Bruce and Darlington NPPs.&#160;We measured the &#916;14C in tree rings from white spruce (Picea glauca) trees sampled across a west-east geographic transect between the NPPs with the aim of better understanding how the atmospheric concentration of 14C has varied locally in this region, while also attempting to pinpoint sources of 14C emissions. Data from our clean-air sites track globally derived 14C data from the &#160;Jungfraujoch clean-air atmospheric sampling site in Switzerland.&#160; Tree-ring 14Cmeasurements from our most densely populated site near the city of Toronto are depleted in 14C, reflecting fossil fuel combustion. Conversely, 14C measurements at our site nearest the Pickering and Darlington NPPs are the most enriched. Our results give insight into how tree rings record 14C and how well they compare to established atmospheric sampling techniques.&#160;

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DENDROCHRONOLOGY AND RADIOCARBON DATING

Radiocarbon ◽

10.1017/rdc.2021.97 ◽

2021 ◽

pp. 1-20

Author(s):

Charlotte L Pearson ◽

Steven W Leavitt ◽

Bernd Kromer ◽

Sami K Solanki ◽

Ilya Usoskin

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Calibration Curve ◽

Radiocarbon Dating ◽

The Holocene ◽

Ocean Atmosphere ◽

The 1950S ◽

Answering Questions

ABSTRACT Both dendrochronology and radiocarbon (14C) dating have their roots back in the early to mid-1900s. Although they were independently developed, they began to intertwine in the 1950s when the founder of dendrochronology, A. E. Douglass, provided dated wood samples for Willard Libby to test his emerging 14C methods. Since this early connection, absolutely dated tree-rings have been key to calibration of the Holocene portion of the 14C timescale. In turn, 14C dating of non-calendar-dated tree-rings has served to place those samples more precisely in time, advance development of long tree-ring chronologies, and bring higher resolution to earlier portions of the 14C calibration curve. Together these methods continue to shape and improve chronological frameworks across the globe, answering questions in archaeology, history, paleoclimatology, geochronology, and ocean, atmosphere, and solar sciences.

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14C Calibration in the Southern Hemisphere and the Date of the Last Taupo Eruption: Evidence from Tree-Ring Sequences

Radiocarbon ◽

10.1017/s0033822200030599 ◽

1995 ◽

Vol 37 (2) ◽

pp. 155-163 ◽

Cited By ~ 71

Author(s):

R. J. Sparks ◽

W. H. Melhuish ◽

J.W. A. McKee ◽

John Ogden ◽

J. G. Palmer ◽

...

Keyword(s):

New Zealand ◽

Southern Hemisphere ◽

Northern Hemisphere ◽

Tree Ring ◽

Tree Rings ◽

Calibration Curve ◽

Systematic Difference ◽

Calibration Data ◽

Northern And Southern Hemispheres

Tree rings from a section of Prumnopitys taxifolia (matai) covering the period ad 1335–1745 have been radiocarbon dated and used to generate a 14C calibration curve for southern hemisphere wood. Comparison of this curve with calibration data for northern hemisphere wood does not show a systematic difference between 14C ages measured in the northern and southern hemispheres. A floating chronology covering 270 yr and terminating at the last Taupo (New Zealand) eruption, derived from a sequence of 10-yr samples of tree rings from Phyllocladus trichomanoides (celery pine, or tanekaha), is also consistent with the absence of a systematic north-south difference, and together with the matai data, fixes the date of the Taupo eruption at ad 232 ± 15.

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Dating of Late Pleistocene Tree-Ring Series from Japan

Radiocarbon ◽

10.1017/s0033822200047305 ◽

2012 ◽

Vol 54 (3-4) ◽

pp. 625-633 ◽

Cited By ~ 5

Author(s):

J van der Plicht ◽

M Imamura ◽

M Sakamoto

Keyword(s):

Tree Ring ◽

Late Pleistocene ◽

Tree Rings ◽

Calibration Curve ◽

Annual Rings ◽

Age Range

We have radiocarbon dated series of tree rings from 2 fossil trees (named ND-113 and the Fuji tree) buried in fossil volcanic avalanche deposits in Japan. They are dendrochronologically floating, dating beyond the tree-ring part of the 14C calibration curve. The trees show about 350 and 400 annual rings, respectively, which are dated in intervals of 2 to 10 yr. Both sequences are wiggle-matched to the calibration curve IntCal09. This resulted in an age range of 16,534–16,204 cal BP for ND-113, and 23,678–23,290 cal BP for the Fuji tree.

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Large14C excursion in 5480 BC indicates an abnormal sun in the mid-Holocene

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1613144114 ◽

2017 ◽

Vol 114 (5) ◽

pp. 881-884 ◽

Cited By ~ 26

Author(s):

Fusa Miyake ◽

A. J. Timothy Jull ◽

Irina P. Panyushkina ◽

Lukas Wacker ◽

Matthew Salzer ◽

...

Keyword(s):

Tree Rings ◽

Time Resolution ◽

Solar Minimum ◽

Cosmic Ray ◽

Solar Proton ◽

The Past ◽

Pine Tree ◽

Unknown Phase ◽

Increase Rate ◽

Bristlecone Pine

Radiocarbon content in tree rings can be an excellent proxy of the past incoming cosmic ray intensities to Earth. Although such past cosmic ray variations have been studied by measurements of14C contents in tree rings with ≥10-y time resolution for the Holocene, there are few annual14C data. There is a little understanding about annual14C variations in the past, with the exception of a few periods including the AD 774−77514C excursion where annual measurements have been performed. Here, we report the result of14C measurements using the bristlecone pine tree rings for the period from 5490 BC to 5411 BC with 1- to 2-y resolution, and a finding of an extraordinarily large14C increase (20‰) from 5481 BC to 5471 BC (the 5480 BC event). The14C increase rate of this event is much larger than that of the normal grand solar minima. We propose the possible causes of this event are an unknown phase of grand solar minimum, or a combination of successive solar proton events and a normal grand solar minimum.

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Detection of solar proton events by using radiocarbon in tree-rings

10.5194/egusphere-egu2020-17774 ◽

2020 ◽

Author(s):

Nicolas Brehm ◽

Marcus Christl ◽

Hans-Arno Synal ◽

Raimund Muscheler ◽

Florian Adolphi ◽

...

Keyword(s):

Carbon Cycle ◽

Tree Ring ◽

Tree Rings ◽

Cosmic Ray ◽

Solar Proton ◽

Galactic Cosmic Rays ◽

The Sun ◽

Cosmogenic Radionuclides ◽

Cosmogenic Nuclide ◽

Solar Proton Events

Our Sun erratically expels large amounts of energetic particles into the interplanetary space and towards Earth, which can be observed as so-called solar proton events (SPE). A strong SPE might cause major damage to satellites and could even disrupt transformers at the ground1. This rises the questions how often strong SPEs occur. Since direct observations of SPEs are limited to the last decades, cosmogenic radionuclides can be used to detect such events further back in time. The production rate of cosmogenic nuclides, such as radiocarbon, is primarily dependent on the incoming flux of highly energetic galactic cosmic rays (GCR). Under normal conditions, the Sun&#8217;s magnetic field carried by the (low energy) solar protons shields us from (high energy) GCRs, resulting in a lower production of cosmogenic radionuclides when the Sun is active. During a SPE, however, the sudden and drastic increase of high the energy solar protons themselves may lead to an elevated production of cosmogenic radionuclides on Earth. Only recently, such sharp increases in cosmogenic nuclide production occurring within less than one year have been detected in several radionuclide records (10Be, 36Cl, 14C) from ice core and tree ring records, and have been attributed to SPEs2,3.Until now, only three SPE could confidently be detected in cosmogenic radionuclide records1,4,5. The reason for this is a general lack of accurately dated and annually resolved radionuclide records and/or the strong dampening of the production signal e.g. by the carbon cycle. To find and identify such events we measured radiocarbon in tree ring records at annual resolution with accelerator mass spectrometry (AMS). In this new, accurately dated and annually resolved 14C record spanning the past about 1000 yr we found several new candidates for SPEs. Their timing and amplitude in terms of cosmogenic nuclide production was characterized by using a global carbon cycle box model. Once unambiguously identified such spiked production increases recorded in the absolutely dated tree ring record have a great potential to be used as a global tool to synchronize other not well dated (climate) records with cosmogenic radionuclides (e.g. 10Be, 36Cl).1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Schrijver, C. J. et al. (2012) Estimating the frequency of extremely energetic solar events, based on solar, stellar, lunar, and terrestrial records. Journal of Geophysical Research: Space Physics 1172&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Miyake, F., Masuda, K. & Nakamura, T. (2013) Another rapid event in the carbon-14 content of tree rings. Nature communications 4, 17483&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Mekhaldi, F. et al. (2015) Multiradionuclide evidence for the solar origin of the cosmic-ray events of &#7424;&#7429; 774/5 and 993/4. Nature Communications 6, 86114&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Miyake, F., Nagaya, K., Masuda, K. & Nakamura, T. A (2012) signature of cosmic-ray increase in AD 774-775 from tree rings in Japan. Nature 486, 240-2425&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; O'Hare, P. et al. (2019) Multiradionuclide evidence for an extreme solar proton event around 2,610 B.P. ( approximately 660 BC). Proc Natl Acad Sci U S A 116, 5961-5966

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A Note on Single-Year Calibration of the Radiocarbon Time Scale, AD 1510–1954

Radiocarbon ◽

10.1017/s0033822200013813 ◽

1993 ◽

Vol 35 (1) ◽

pp. 67-72 ◽

Cited By ~ 20

Author(s):

Minze Stuiver

Keyword(s):

Tree Ring ◽

High Precision ◽

Tree Rings ◽

Calibration Curve ◽

Time Scale ◽

Growing Season ◽

Precision Measurements ◽

Radiocarbon Age ◽

Data Points ◽

Age Determinations

Most data in this Calibration Issue are based on radiocarbon age determinations of tree-ring samples with dendrochronologically determined calibrated (cal) ages. For high-precision measurements, substantial sample amounts are needed, and the processed wood usually spans 10 or 20 tree rings. Thus, the calibration curve data points usually have decadal, or bidecadal, spacing. These curves, to be used for the calibration of samples formed over 1 or 2 decades, may not be fully applicable to samples (leaves, twigs, etc.) formed in a single growing season.

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New Single-Year Radiocarbon Measurements Based on Danish oak Covering the Periods AD 692–790 and 966–1057

Radiocarbon ◽

10.1017/rdc.2019.107 ◽

2019 ◽

Vol 62 (4) ◽

pp. 969-987 ◽

Cited By ~ 3

Author(s):

Sabrina G K Kudsk ◽

Bente Philippsen ◽

Claudia Baittinger ◽

Alexandra Fogtmann-Schulz ◽

Mads F Knudsen ◽

...

Keyword(s):

Tree Rings ◽

Calibration Curve ◽

Cosmic Ray ◽

Relevant Information ◽

The Past ◽

One Year

ABSTRACTSingle-year measurements of radiocarbon (14C) in tree rings have led to the discovery of rapid cosmic-ray events as well as longer lasting anomalies, which have given new insights into the Sun’s behavior in the past. Here, we present two new single-year 14C records based on Danish oak that span the periods AD 692–790 and 966–1057, respectively, and consequently include the two rapid cosmic-ray events in AD 775 and 994. The new data are presented along with relevant information on the dendrochronological dating of the wood pieces, implying that these new measurements may contribute towards generating the next international calibration curve. The new data covering the AD 966–1057 period suggest that the increase in atmospheric 14C associated with the cosmic-ray event in AD 994 actually occurred in AD 993, i.e. one year earlier than the year reported in Fogtmann-Schulz et al. (2017) based on oak from southern Denmark. Careful reanalysis of the dendrochronology that underpins the new 14C records based on oak material from southern Denmark reveals that the cosmic-ray event reported in Fogtmann-Schulz et al. (2017) actually took place in AD 993.

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