scholarly journals Δ14C PEAKS APPEARING IN EARLYWOOD AND LATEWOOD TREE RINGS (AD 770–780) IN NORTHEASTERN ARIZONA

Radiocarbon ◽  
2020 ◽  
pp. 1-6
Author(s):  
J H Park ◽  
J Southon ◽  
JW Seo ◽  
P P Creasman ◽  
W Hong ◽  
...  
Keyword(s):  
Tree Rings ◽  
High Latitude ◽  
Pinus Edulis ◽  
Lateral Transfer ◽  
Late Winter ◽  
National Monument ◽  
Small Rise ◽  
Pinyon Pine

ABSTRACT The AD 775 peak in Δ14C (henceforth, M12) was first measured by Miyake et al. and has since been confirmed globally. Here we present earlywood and latewood Δ14C values from tree rings of pinyon pine (Pinus edulis) from Mummy Cave, Canyon de Chelly National Monument, Chinle, Arizona, USA, for the period AD 770–780. These data reconfirm the timing of M12 and show a small rise in Δ14C in AD 774 latewood. Allowing for the delay in lateral transfer of radiocarbon produced at high latitude, this suggests that 14C peak production occurred in late winter or spring of AD 774. Additionally, Δ14C decreased slightly in the earlywood of AD 775 and increased in the latewood of AD 775 to a higher level than that observed in AD 774.

Age-related climate sensitivity in Pinus Edulis at Dinosaur National Monument, Colorado, USA

2018 ◽  
Vol 52 ◽  
pp. 40-47 ◽  
Author(s):  
Dustin P. Hanna ◽  
Donald A. Falk ◽  
Thomas W. Swetnam ◽  
William Romme
Keyword(s):  
Climate Sensitivity ◽  
Pinus Edulis ◽  
National Monument ◽  
Age Related ◽  
Dinosaur National Monument

scholarly journals Accelerator-Measured 14C Activity in Tree Rings From the Vicinity of the First Atomic Bomb Test

Radiocarbon ◽  
1989 ◽  
Vol 31 (03) ◽  
pp. 762-765 ◽  
Author(s):  
S W Leavitt ◽  
Austin Long
Keyword(s):  
New Mexico ◽  
Neutron Flux ◽  
Tree Rings ◽  
Atomic Bomb ◽  
Test Site ◽  
Pinus Edulis ◽  
Site Analysis ◽  
Bomb Test ◽  
White Sands ◽  
The Trinity

Detonation of the first fission bomb at White Sands, New Mexico, on July 16, 1945, produced a tremendous neutron flux capable of creating tritium and radiocarbon byproducts. We sampled a 115-year-old pinyon (Pinus edulis) 10km east of the Trinity test site to determine 14C evidence of this event. The most likely mechanism for this enrichment in the 1945 tree ring would be fixation of 14CO2 produced at the blast site and carried with the fallout cloud over the pinyon site. Analysis of cellulose of the 1944 and 1945 rings shows δ13C values of −19.9 and −19.5, respectively, and 14C activity (fraction of modern uncorrected for δ13C) as 0.991 ± .005 and 0.991 ± .006, respectively. It is likely that the duration and/or concentration of the 14CO2 exposure was not sufficient to increase 14C activity expected for that year.

Persistence of Pinyon Pine Snags and Logs in Southwestern Colorado

2005 ◽  
Vol 20 (4) ◽  
pp. 247-252 ◽  
Author(s):  
W. R. Jacobi ◽  
H.S. J. Kearns ◽  
D. W. Johnson
Keyword(s):  
Similar Condition ◽  
Bark Beetles ◽  
Structural Condition ◽  
Root Disease ◽  
Pinus Edulis ◽  
Rating System ◽  
Permanent Plots ◽  
Time Since Death ◽  
Significant Difference ◽  
Pinyon Pine

Abstract We examined the persistence of pinyon pine (Pinus edulis Engelm.) standing snags and downed logs in southwestern Colorado pinyon-juniper woodlands. The time since death of pinyon pines killed by bark beetles, black stain root disease, or unknown causes in three study areas in southwestern Colorado was determined through monitoring of permanent plots and dendrochronological crossdating methods. The structural condition and form of the trees was recorded and related to the time since death. Pinyon snags may persist for up to 25 years, with persistence of intact snags averaging 8.4 years and broken snags averaging 13.2 years. Sound logs had been dead for a mean of 9.8 years, whereas more fragmented logs had been dead for a mean of 14.4 years. Extremely fragmented trees had been dead for 16.2 years. There was no statistically significant difference in the time since death for snags versus logs in similar condition classes. A simplified rating system to determine the number of years dead for pinyon pine based on form and condition is provided. West. J. Appl. For. 20(4):247–252.

Blue Reflectance Provides a Surrogate for Latewood Density of High-latitude Pine Tree Rings

2002 ◽  
Vol 34 (4) ◽  
pp. 450-453 ◽  
Author(s):  
D. McCarroll ◽  
E. Pettigrew ◽  
A. Luckman ◽  
F. Guibal ◽  
J.-L. Edouard
Keyword(s):  
Tree Rings ◽  
High Latitude ◽  
Pine Tree ◽  
Latewood Density ◽  
Blue Reflectance

scholarly journals Quantifying transport into the Arctic lowermost stratosphere

2010 ◽  
Vol 10 (23) ◽  
pp. 11623-11639 ◽  
Author(s):  
A. Werner ◽  
C. M. Volk ◽  
E. V. Ivanova ◽  
T. Wetter ◽  
C. Schiller ◽  
...  
Keyword(s):  
High Latitude ◽  
Trace Gases ◽  
Polar Vortex ◽  
The Arctic ◽  
Late Winter ◽  
Mass Balance Calculation ◽  
Air Masses ◽  
History Of ◽  
Simple Mass

Abstract. In the Arctic winter 2003, in-situ measurements of the long-lived trace gases N2O, CFC-11 (CCl3F), H-1211 (CBrClF2), CH4, O3 and H2O have been performed on board the high-altitude aircraft M55 Geophysica. The data are presented and used to study transport into the lowermost stratosphere (LMS). The LMS can be regarded as a mixture of fractions of air originating in (i) the troposphere, (ii) the extra-vortex stratosphere above 400 K and (iii) the Arctic vortex above 400 K. These fractions are determined using a simple mass balance calculation. The analysis exhibits a strong tropospheric influence of 50% ± 15% or more in the lowest 20 K of the high-latitude LMS. Above this region the LMS is dominated by air masses having descended from above 400 K. Below the Arctic vortex region at potential temperatures above 360 K, air in the LMS is a mixture of extra-vortex stratospheric and vortex air masses. The vortex fraction increases from about 40% ± 15% at 360 K to 100% at 400 K for equivalent latitudes >70° N. This influence of air masses descending through the bottom of the polar vortex increases over the course of the winter. By the end of winter a significant fraction of 30% ± 10% vortex air in the LMS is found even at an equivalent latitude of 40° N. Since the chemical and dynamical history of vortex air is distinct from that of mid-latitude stratospheric air masses, this study implies that the composition of the mid- to high-latitude LMS during late winter and spring is significantly influenced by the Arctic vortex.

Terminal megasporangiate cones in pinyon pine

1969 ◽  
Vol 47 (2) ◽  
pp. 259-259
Author(s):  
Ronald M. Lanner
Keyword(s):  
Pinus Edulis ◽  
Terminal Position ◽  
Apical Meristems ◽  
Shoot Apical Meristems ◽  
Pinyon Pine

Three megasporangiate cones apparently formed directly by shoot apical meristems were found in a terminal position on a pinyon pine (Pinus edulis Engelm.).

Patterns of microhabitat use in a sympatric lizard assemblage

2002 ◽  
Vol 80 (12) ◽  
pp. 2226-2234 ◽  
Author(s):  
Sarah E James ◽  
Robert T M'Closkey
Keyword(s):  
Function Analysis ◽  
Niche Overlap ◽  
The Other ◽  
Microhabitat Use ◽  
Similar Species ◽  
Lizard Species ◽  
National Monument ◽  
Niche Differences ◽  
Juniper Woodland ◽  
Pinyon Pine

The distribution of animals among habitats and microhabitats has frequently been used to examine patterns of niche overlap. We characterized microhabitat differences within an assemblage of four phrynosomatine lizard species (Sceloporus graciosus, Sceloporus undulatus, Urosaurus ornatus, and Uta stansburiana) that are commonly syntopic in the pinyon pine – juniper woodland habitat on the elevated mesas of western Colorado. We censused lizard populations and recorded microhabitat characteristics of areas surrounding capture sites within Colorado National Monument, U.S.A. Discriminant function analysis of microhabitat features extracted two significant roots, explaining 89% of the microhabitat variation observed among species. Planned comparisons of canonical scores revealed two significant microhabitat niche differences. First, the microhabitat niche of U. ornatus was distinguished from those of all the other species by higher perch height and more vertical substrate, indicating this species' arboreality. Second, the microhabitat niche of S. graciosus was distinguished from those of the other species by having more flatland and less rock, indicating the use of more open flat sandy areas within the pinyon pine – juniper woodland by this terrestrial species. Although the observed differences in microhabitat may influence the coexistence of these ecologically similar species, changes in relative abundance of the species over time suggest alternative mechanisms of coexistence.

scholarly journals The influence of the stratosphere on the tropospheric zonal wind response to CO<sub>2</sub> doubling

2010 ◽  
Vol 10 (10) ◽  
pp. 23895-23925
Author(s):  
Y. B. L. Hinssen ◽  
C. J. Bell ◽  
P. C. Siegmund
Keyword(s):  
Northern Hemisphere ◽  
Zonal Wind ◽  
High Latitude ◽  
Climate Models ◽  
Polar Vortex ◽  
Late Winter ◽  
Wave Forcing ◽  
Eddy Heat Flux ◽  
Wind Response ◽  
Hemisphere Winter

Abstract. The influence of a CO2 doubling on the stratospheric potential vorticity (PV) is examined in two climate models. Subsequently, the influence of changes in the stratosphere on the tropospheric zonal wind response is investigated, by inverting the stratospheric PV. Radiative effects dominate the stratospheric response to CO2 doubling in the Southern Hemisphere. These lead to a stratospheric PV increase at the edge of the polar vortex, resulting in an increased westerly influence of the stratosphere on the tropospheric midlatitude winds in late winter. In the Northern Hemisphere, dynamical effects are also important. Both models show a reduced polar PV and an enhanced midlatitude PV in the Northern Hemisphere winter stratosphere. These PV changes are related to an enhanced wave forcing of the winter stratosphere, as measured by an increase in the 100 hPa eddy heat flux, and result in a reduced westerly influence of the stratosphere on the high latitude tropospheric winds. In one model, the high latitude PV decreases are, however, restricted to higher altitudes, and the tropospheric response due to the stratospheric changes is dominated by an increased westerly influence in the midlatitudes, related to the increase in midlatitude PV in the lower stratosphere. The tropospheric response in zonal wind due to the stratospheric PV changes is of the order of 0.5 to 1 m s−1. The total tropospheric response has a somewhat different spatial structure, but is of similar magnitude. This indicates that the stratospheric influence is of importance in modifying the tropospheric zonal wind response to CO2 doubling.

scholarly journals Quantifying transport into the Arctic lowermost stratosphere

2009 ◽  
Vol 9 (1) ◽  
pp. 1407-1446 ◽  
Author(s):  
A. Werner ◽  
C. M. Volk ◽  
E. V. Ivanova ◽  
T. Wetter ◽  
C. Schiller ◽  
...  
Keyword(s):  
High Latitude ◽  
Trace Gases ◽  
Polar Vortex ◽  
The Arctic ◽  
Late Winter ◽  
Mass Balance Calculation ◽  
Air Masses ◽  
History Of ◽  
Simple Mass

Abstract. In-situ measurements of the long-lived trace gases N2O, CFC-11 (CCl3F), H-1211 (CBrClF2), CH4, O3 and H2O performed in the Arctic winter 2003 on board the high-altitude aircraft M55 Geophysica are presented and used to study transport into the lowermost stratosphere (LMS). Fractions of air in the LMS originating in i) the troposphere, ii) the extra-vortex stratosphere above 400 K and iii) the Arctic vortex above 400 K are determined using a simple mass balance calculation. The analysis exhibits a strong tropospheric influence of 50% or more in the lowest 20 K of the high-latitude LMS. Above this region the LMS is dominated by air masses having descended from above 400 K. Below the Arctic vortex region at potential temperatures above 360 K, air in the LMS is a mixture of extra-vortex stratospheric and vortex air masses. The vortex fraction increases from about 40% at 360 K to 100% at 400 K for equivalent latitudes >70° N. This influence of air masses descending through the bottom of the polar vortex increases over the course of the winter. By the end of winter a significant fraction of 30% vortex air in the LMS is found even at an equivalent latitude of 40° N. Since the chemical and dynamical history of vortex air is distinct from that of mid-latitude stratospheric air masses, this study implies that the composition of the mid- to high-latitude LMS during late winter and spring is significantly influenced by the Arctic vortex.

Propagation protocol for pinyon pine (Pinus edulis Engelm.)

2014 ◽  
Vol 15 (3) ◽  
pp. 205-208
Author(s):  
K. J. Woodruff ◽  
D. J. Regan ◽  
A. S. Davis
Keyword(s):  
Pinus Edulis ◽  
Pinyon Pine
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