Reconstructed summer temperature in the northern Rocky Mountains wilderness, USA

AbstractRing widths from whitebark pine (Pinus albicaulisEnglem.) and subalpine larch (Larix lyalliiParl.) collected at three high-elevation sites were used to develop tree-growth chronologies to reconstruct summer temperature anomalies. A step-wise multiple regression procedure was used to screen potential predictor variables to generate a transfer function capable of skillfully reconstructing summer temperature. The resulting regression model explained approximately 38% of the adjusted variance in the instrumental temperature record. The fidelity of the reconstruction was verified using product mean and sign tests, both of which suggested significant predictive power in the reconstructions (p<0.05). Reduction of error (RE) and coefficient of efficiency (CE) measures were both positive, indicating the reconstruction contained useful climate information. Cool periods often coincided with reduced solar activity and/or periods of increased volcanic activity. Differences between this reconstruction and others encompassing a broader geographic scale highlight the importance of developing local reconstructions of climate variability, particularly when used in conjunction with ecological data sets that describe the occurrence of fires or insect epidemics. Mixed and divergent climate-response relationships were evident in the whitebark pine chronologies and suggest subalpine larch may be a more useful species than whitebark pine to target for the development of temperature reconstructions in this region.

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Spatial representativity of air-temperature information from instrumental and ice-core-based isotope records in the European Alps

Annals of Glaciology ◽

10.3189/172756402781816717 ◽

2002 ◽

Vol 35 ◽

pp. 157-161 ◽

Cited By ~ 7

Author(s):

Wolfgang Schöner ◽

Ingeborg Auer ◽

Reinhard Böhm ◽

Lothar Keck ◽

Dietmar Wagenbach

Keyword(s):

Air Temperature ◽

Ice Core ◽

Ice Cores ◽

Summer Precipitation ◽

High Elevation ◽

Summer Temperature ◽

Temperature Variability ◽

Temperature Record ◽

European Alps

AbstractSpatial correlations between Alpine high-elevation and European low-elevation instrumental air temperatures are computed to assess the spatial representativity of a high-Alpine ice-core isotope proxy temperature record. the correlation analyses indicate that air-temperature records at Alpine ice-core drill sites are representative for central Europe, particularly in summer. While Alpine ice cores generally show a large scattering in the conserved section of the year, long-term records from low-accumulation sites consist almost solely of summer precipitation and thus reflect isotope proxy summer-temperature variability. However, correlation between seasonal and annual instrumental air temperature indicates that summer temperature variability provides an adequate approach to annual temperature variability. Comparison of long-term ice-core δ18O records from Colle Gnifetti (4450ma.s.l.), Monte Rosa, Western Alps, with local instrumental summer temperatures inferred from an instrumental network shows good agreement in the long-term scale. Thus Alpine long-term ice-core δ18O records are representative for central European air-temperature variability.

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Current distribution of Nilgiri grass yellow Eurema nilgiriensis Yata (Lepidoptera: Pieridae), with an updated taxonomic key to Eurema of Western Ghats, India

ENTOMON ◽

10.33307/entomon.v44i1.423 ◽

2019 ◽

Vol 44 (1) ◽

pp. 23-32 ◽

Cited By ~ 1

Author(s):

P. C. Sujitha ◽

G. Prasad ◽

R. Nitin ◽

Dipendra Nath Basu ◽

Krushnamegh Kunte ◽

...

Keyword(s):

Current Distribution ◽

Western Ghats ◽

Original Description ◽

High Elevation ◽

Type Locality ◽

Ecological Data ◽

Field Identification ◽

Wing Patterns ◽

Southern Western Ghats ◽

The Nilgiris

Eurema nilgiriensis Yata, 1990, the Nilgiri grass yellow, was described from Nilgiris in southern India. There are not many published records of this species since its original description, and it was presumed to be a high-elevation endemic species restricted to its type locality. Based on the external morphology (wing patterns) as well as the male genitalia, the first confirmed records of the species from Agasthyamalais and Kodagu in the southern Western Ghats, is provided here. This report is a significant range extension for the species outside the Nilgiris, its type locality. Ecological data pertaining to this species as well as the field identification key to all known Eurema of Western Ghats are also presented.

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Incorporating Additional Tree and Environmental Variables in a Lodgepole Pine Stem Profile Model

Western Journal of Applied Forestry ◽

10.1093/wjaf/8.3.86 ◽

1993 ◽

Vol 8 (3) ◽

pp. 86-90

Author(s):

John C. Byrne

Keyword(s):

Environmental Variables ◽

Pinus Contorta ◽

Lodgepole Pine ◽

Linear Equations ◽

The United States ◽

National Forest ◽

Data Sets ◽

Tree Form ◽

Northern Rocky Mountains ◽

Profile Model

Abstract A new variable-form segmented stem profile model is developed for lodgepole pine (Pinus contorta) trees from the northern Rocky Mountains of the United States. I improved estimates of stem diameter by predicting two of the model coefficients with linear equations using a measure of tree form, defined as a ratio of dbh and total height. Additional improvements were obtained by fitting this model to individual national forest data sets. Other tree and environmental variables tested but found of little use in improving stem profile estimates were crown ratio, habitat series, elevation, slope percent, and aspect. West. J. Appl. For. 8(3):86-90.

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Dendrochronological Assessment of Whitebark Pine Response to Past Climate Change: Implications for a Threatened Species in Grand Teton National Park

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2014.4047 ◽

2014 ◽

Vol 37 ◽

pp. 58-64

Author(s):

Kendra McLauchlan ◽

Kyleen Kelly

Keyword(s):

Climate Change ◽

National Park ◽

Fire History ◽

Multiple Stressors ◽

Fire Suppression ◽

Climatic Variability ◽

High Elevation ◽

Whitebark Pine ◽

Grand Teton National Park ◽

Pine Trees

One of the keystone tree species in subalpine forests of the western United States â whitebark pine (Pinus albicaulis, hereafter whitebark pine) â is experiencing a significant mortality event (Millar et al. 2012). Whitebark pine occupies a relatively restricted range in the high-elevation ecosystems in the northern Rockies and its future is uncertain. The current decline of whitebark pine populations has been attributed to pine beetle infestations, blister rust infections, anthropogenic fire suppression, and climate change (Millar et al. 2012). Despite the knowledge that whitebark pine is severely threatened by multiple stressors, little is known about the historic capacity of this species to handle these stressors. More specifically, it is unknown how whitebark pine has dealt with past climatic variability, particularly variation in the type of precipitation (rain vs. snow) available for soil moisture, and how differences in quantity of precipitation have influenced the establishment and growth of modern stands. We propose to study the past responses of whitebark pine to paleoclimatic conditions, which would be useful to park ecologists in developing new conservation and regeneration plans to prevent the extinction of this already severely threatened high-elevation resource. The purpose of this study is to determine in great temporal and spatial detail the demographics of the current stand of whitebark pine trees in the watershed surrounding an unnamed, high-altitude pond (known informally as Whitebark Pine Moraine Pond) located approximately 3.06 miles NW of Jenny Lake in Grand Teton National Park (GTNP). The main objectives of this study were: 1.) To obtain the precise GPS locations of the current stand of whitebark pine trees in the watershed to generate a GIS map detailing their locations. 2.) To obtain increment cores of a subset of the trees in the watershed to estimate age and date of establishment for the current stand of whitebark pines, with particular attention to fire history. 3.) To analyze ring widths from core samples to identify climatic indicators that may influence the regeneration and survival of whitebark pine.

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Modeling the stratospheric warming following the Mt. Pinatubo eruption: uncertainties in aerosol extinctions

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-11221-2013 ◽

2013 ◽

Vol 13 (22) ◽

pp. 11221-11234 ◽

Cited By ~ 53

Author(s):

F. Arfeuille ◽

B. P. Luo ◽

P. Heckendorn ◽

D. Weisenstein ◽

J. X. Sheng ◽

...

Keyword(s):

General Circulation ◽

Climate Model ◽

Circulation Model ◽

Temperature Record ◽

Data Sets ◽

Stratospheric Warming ◽

Data Set ◽

Tropical Tropopause ◽

Pinatubo Eruption ◽

Tropopause Region

Abstract. In terms of atmospheric impact, the volcanic eruption of Mt. Pinatubo (1991) is the best characterized large eruption on record. We investigate here the model-derived stratospheric warming following the Pinatubo eruption as derived from SAGE II extinction data including recent improvements in the processing algorithm. This method, termed SAGE_4λ, makes use of the four wavelengths (385, 452, 525 and 1024 nm) of the SAGE II data when available, and uses a data-filling procedure in the opacity-induced "gap" regions. Using SAGE_4λ, we derived aerosol size distributions that properly reproduce extinction coefficients also at much longer wavelengths. This provides a good basis for calculating the absorption of terrestrial infrared radiation and the resulting stratospheric heating. However, we also show that the use of this data set in a global chemistry–climate model (CCM) still leads to stronger aerosol-induced stratospheric heating than observed, with temperatures partly even higher than the already too high values found by many models in recent general circulation model (GCM) and CCM intercomparisons. This suggests that the overestimation of the stratospheric warming after the Pinatubo eruption may not be ascribed to an insufficient observational database but instead to using outdated data sets, to deficiencies in the implementation of the forcing data, or to radiative or dynamical model artifacts. Conversely, the SAGE_4λ approach reduces the infrared absorption in the tropical tropopause region, resulting in a significantly better agreement with the post-volcanic temperature record at these altitudes.

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Use of Whitebark Pine (Pinus albicaulis) seeds by GPS-collared Grizzly Bears (Ursus arctos) in Banff National Park, Alberta

The Canadian Field-Naturalist ◽

10.22621/cfn.v135i1.2165 ◽

2021 ◽

Vol 135 (1) ◽

pp. 61-67

Author(s):

David Hamer

Keyword(s):

National Park ◽

Ursus Arctos ◽

High Elevation ◽

Habitat Characteristics ◽

Grizzly Bears ◽

Pinus Albicaulis ◽

Whitebark Pine ◽

Gps Collars ◽

Additional Information ◽

Banff National Park

Seeds of Whitebark Pine (Pinus albicaulis) are a major food for Grizzly Bears (Ursus arctos) in the Yellowstone ecosystem. In Canada, Grizzly Bears are known to eat Whitebark Pine seeds, but little additional information, such as the extent of such use and habitat characteristics of feeding sites, is available. Because Grizzly Bears almost always obtain Whitebark Pine seeds by excavating cones from persistent caching sites (middens) made by Red Squirrels (Tamiasciurus hudsonicus), it is possible to infer Whitebark Pine feeding when bears are located near excavated middens in Whitebark Pine stands. During 2013–2018, I conducted a retrospective study in Banff National Park using data from 23 Grizzly Bears equipped by Parks Canada staff with global positioning system (GPS) collars. My objectives were to use GPS fixes to determine the percentage of these bears that had been located in close proximity to excavated middens containing Whitebark Pine seeds and to describe the habitat at these excavated middens. I linked 15 bears (65%) to excavated middens and, by inference, consumption of Whitebark Pine seeds. Excavated middens occurred on high-elevation (mean 2103 ± 101 [SD] m), steep (mean 26° ± 8°) slopes facing mostly (96%) north through west (0–270°). Use of Whitebark Pine seeds by at least 65% of the 23 studied Grizzly Bears suggests that conservation of Whitebark Pine in Banff National Park would concomitantly benefit the at-risk population of Grizzly Bears.

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Cryogenic cave carbonate formation during the Industrial Era in the Central Pyrenees (Iberian Peninsula)

10.5194/egusphere-egu21-14487 ◽

2021 ◽

Author(s):

Miguel Bartolomé ◽

Ana Moreno ◽

Marc Luetscher ◽

Christoph Spötl ◽

Maria Leunda ◽

...

Keyword(s):

Spring Water ◽

Ice Formation ◽

Cumulative Probability ◽

Temperature Record ◽

Permafrost Degradation ◽

The North ◽

Carbonate Formation ◽

Discontinuous Permafrost ◽

Ice Retreat ◽

Instrumental Temperature

<p>Cryogenic cave carbonates (CCC) are rare speleothems that form when water freezes inside cave ice bodies. CCC have been used as an proxy for permafrost degradation, permafrost thickness, or subsurface ice formation. The presence of these minerals is usually attributed to warm periods of permafrost degradation. We found coarse crystalline CCC types within transparent, massive congelation ice in two Pyrenean ice caves in the Monte Perido Massif: Devaux, located on the north face at 2828 m a.s.l., and Sarrios 6, located in the south face at 2780 m a.s.l. The external mean annual air temperature (MAAT) at Devaux is ~ 0&#176;C, while at Sarrios 6 is ~ 2.5&#176;C. In the Monte Perdido massif discontinuous permafrost is currently present between 2750 and 2900 m a.s.l. and is more frequent above 2900 m a.s.l. in northern faces. In Devaux, air and rock temperatures, as well as the presence of hoarfrost and the absence of drip sites indicate a frozen host rock. Moreover, a river flows along the main gallery, and during winters the water freezes at the spring causing backflooding in the cave. In contrast, Sarrios 6 has several drip sites, although the gallery where CCC were collected is hydrologically inactive. This gallery opened in recent years due to ice retreat. During spring, water is present in the gallery due to the overflow of ponds forming beneath drips. CCC commonly formed as sub-millimeter-size spherulites, rhombohedrons and rafts. <sup>230</sup>Th ages of the same CCC morphotype indicate that their formation took place at 1953&#177;7, 1959&#177;14, 1957&#177;14, 1958&#177;15, 1974&#177;16 CE in Devaux, while in Sarrios 6 they formed at 1964&#177;5, 1992&#177;2, 1996&#177;1 CE. The cumulative probability density function indicates that the most probable formation occurred 1957-1965 and 1992-1997. The instrumental temperature record at 2860 m a.s.l. indicates positive MAAT in 1964 (0.2&#176;C) and 1997 (0.8&#176;C). CCC formation could thus correspond with those two anomalously warm years. The massive and transparent ice would indicate a sudden ingress of water and subsequent slow freezing inside both caves during those years. Probably, CCC formation took place at a seasonal scale during the annual cycle.</p>

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Numerical and taxonomic scale of analysis in paleoecological data sets: Examples from neo-tropical Pleistocene reef coral communities

Journal of Paleontology ◽

10.1017/s0022336000039652 ◽

2001 ◽

Vol 75 (3) ◽

pp. 546-563 ◽

Cited By ~ 9

Author(s):

John M. Pandolfi

Keyword(s):

Reef Coral ◽

Distribution Data ◽

Data Sets ◽

Geographic Scale ◽

Genus Level ◽

Coral Communities ◽

The Caribbean ◽

Presence And Absence ◽

Rank Abundance ◽

Scale Of Analysis

I investigated the degree to which the interpretation of reef coral distribution data is influenced by the numerical and taxonomic scale of analysis in Pleistocene coral communities from the Caribbean Sea. Patterns of community differentiation analyzed at both species and genus levels showed only small differences using different numerical scales (relative abundance, rank abundance and species presence and absence). Whereas some differences were observed between species and genus level patterns, they had little effect on paleoecological interpretations. The greatest differences occurred when presence and absence analyses of assemblages sampled along 40-m transects were compared with those sampled along 40-m transects augmented by a one-hour search for rare taxa. These results suggest that paleoecological interpretations of Quaternary coral communities are robust to numerical scale of analysis at the species and genus level, and to taxonomic scale between the species and genus level. However, interpretations of community structure are sensitive to sampling intensity, geographic scale, and sample size.

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