Cold Mountain Research Articles

A blueprint for coupling a hydrological model with fine- and coarse-scale atmospheric regional climate change models for probabilistic streamflow projections

In cold regions, climate change, including warming and changes in snowmelt dynamics, have profound impacts on streamflow patterns, often leading to flooding events. Understanding the projected changes in hydrometeorological factors contributing to streamflow, such as snowmelt runoff and rain-on-snowmelt, is crucial for effective adaptation and mitigation strategies. It is also essential to consider uncertainty in streamflow projections and incorporate this uncertainty into flood predictions. This study presents a blueprint for calculating probabilistic future streamflow and flow duration curves in a mountainous cold region. The methodology integrated forcings from an atmospheric model (WRF) with a hydrological model (MESH) at fine spatial (4 km) and temporal (3-hourly) resolutions. To account for uncertainty, an ensemble of 15 CanRCM4 regional climate simulations with varying boundary conditions for the RCP 8.5 scenario was utilized. A novel method was developed to perturb the CanRCM4 simulations’ precipitation using a WRF Pseudo Global Warming run to incorporate uncertainty. This comprehensive approach revealed significant uncertainty in streamflow driven by internal variability. WRF-driven simulations without uncertainty showed a decrease in future streamflow extremes, while the perturbed simulations demonstrated the potential for substantially higher values under climate change. Moreover, the study derived probabilistic flow duration curves from the streamflow projections, aiding in estimating flood frequency for floodplain mapping when driving local hydraulic models. The methodology developed in this work can be extended to other river basins in Canada and elsewhere where gridded downscaled climate model outputs are available.

Cold mountain stream chironomids (Diptera) of the genus Diamesa indicate both historical and recent climate change.

Chironomids of the genus Diamesa (Meigen, 1835, Diptera: Chironomidae) inhabit cold, oxygen-rich running waters. We have investigated the presence of Diamesa and other freshwater macroinvertebrates at 22 stream sampling sites in 3 European high mountain regions (the Central Pyrenees, the Ötztal Alps, and the Tatra Mountains) to establish suitable temperature conditions for Diamesa dominance. It has been generally accepted that their high abundance was linked to the presence of glaciers; however, we have shown that in the Tatra Mountains, where there are no glaciers, the conditions for the dominance of Diamesa species are created due to permanent snowfields, the geographical orientation of the valley and shading by the surrounding high peaks. The historical connection of Diamesa to glaciers was investigated from the paleolimnological records of subfossil chironomid assemblages from the Bohemian Forest, where glaciers disappeared before or during the Late Glacial period. As expected, water temperature seems to be the main driver of Diamesa distribution, and we determined that the relative abundance of Diamesa species was significantly higher at the sites with a mean July water temperature below 6.5 °C. The Diamesa-dominated stream communities seems to be endangered due to ongoing climate warming and this assumption is supported by our paleolimnological results from the Bohemian Forest lakes, where Diamesa has disappeared due to warming of lake inflows at the beginning of the Holocene. These findings strengthen the former suggestions that some Diamesa species could be used as an indicator for tracking recent environmental changes in vulnerable ecosystems of cold mountain streams.

Role of ectomycorrhizal colonization in enhancement of nutrients for survival of plants collected from mountainous cold stress areas

BackgroundEctomycorrhizal (ECM and ECM-like) structures associated with plant root systems are a challenge for scientists. The dispersion pattern of roots within the soil profile and the nutritional conditions are both favourable factors to motivate the plants to make ECM associations.ResultsThis study discusses the colonization of mycorrhizal associations in Kobresia and Polygonum species including Polygonum viviparum, Kobresia filicina, K. myosuroides, Alnus nitida, Betula pendula, Pinus sylvestris, and Trifolium repens grown naturally in cold stressed soils of Gilgit-Baltistan (high-altitude alpine Deosai plains), Hazara, Swat, Dir, and Bajaur. Sieved soil batches were exposed to +5 °C (control), -10, -20, -30, -40, -50, -125 °C for 5 h, and selected plants were sown to these soils for 10 weeks under favourable conditions for ECM colonization. Ectomycorrhizal associations were examined in the above mentioned plants. Some ECM fungi have dark mycelia that look like the mantle and Hartig net. Examples of these are Kobresia filicina, K. myosuroides, and Polygonum viviparum. Findings of this study revealed that K. myosuroides excelled in ECM root tip length, dry mass, and NH4 concentration at -125 °C. Contrarily, A. nitida demonstrated the lower values, indicated its minimum tolerance. Notably, T. repens boasted the highest nitrogen concentration (18.7 ± 1.31 mg/g), while P. sylvestris led in phosphorus (3.2 ± 0.22 mg/g). The B. pendula showed the highest potassium concentration (9.4 ± 0.66 mg/g), emphasising species-specific nutrient uptake capabilities in extreme cold conditions. The PCA analysis revealed that the parameters, e.g., NH4 in soil mix (NH4), NO3 in soil mix (NO3), phosphorus in soil in species of Polygonum viviparum, Kobresia filicina, K. myosuroides, Alnus nitida, Betula pendula, Pinus sylvestris, and Trifolium repens are most accurately represented in cases of + 5 °C, -10 °C, and -20 °C temperatures. On the other hand, the parameters for ECM root tips (ECM) and Dry Mass (DM) are best described in -40 °C, -50 °C, and − 125 °C temperatures. All parameters have a strong influence on the variability of the system indicated the efficiency of ECM. The heatmap supported the nutrients positively correlated with ECM colonization with the host plants.ConclusionAt lower temperatures, hyphae and spores in roots were reduced, while soluble phosphorus concentrations of leaves were increased in cold stress soils. Maximum foliar nutrient concentrations were found in K. myosuroides at the lowest temperature treatments due to efficient functioning and colonization of ECM.

Feeding ration of yaks of the Kyrgyz population and its influence on the biochemical composition of milk

Yaks are the large herbivorous ruminants that live in high mountain pastures at altitudes from 2,000 to 4,000 m above sea level. This environment is quite harsh, and yaks calmly tolerate extreme cold — down to minus 40 ºС. The main food of yaks are herbaceous plants, the vegetation season of which in a cold mountain climate is short, about 3–4 months, and therefore they feed mostly on wilted pasture, which is, in principle, sufficient for these animals. At the end of winter, when the amount of pasture feed decreases, the animals become malnourished and lose weight. Therefore, yak farmers often face the need to feed their animals in winter. A complete ration of an animal, along with other factors, has a significant impact on the composition of milk and its productive ability. The aim of the work is to study the chemical composition, in particular the protein fraction, of the milk of yaks living in the mountainous regions of Kyrgyzstan in comparison with the milk of yaks from different regions of the world. The object of the study was milk of yaks inhabiting the highland regions of Naryn province of Kyrgyzstan. Samples were collected and tested according to standard methods. Studies have shown that the milk of yaks from the Kyrgyz population contains more protein (5.66%) than milk from yaks in the mountains of China, Russia and Mongolia (4.95, 4.55 and 5.3%, respectively). Milk we studied is high in amino acids such as methionine, lysine, proline, phenylalanine, and alanine. Seasonal (spring, summer) changes in the protein composition (whey proteins, casein proteins), amino acid profile, total nitrogen, non-protein nitrogen of yak milk were also studied. The total content of amino acids in the milk of Kyrgyz female yaks is noticeably higher in spring (6189.96 mg/100 g) than in summer (5101.47 mg/100 g). The research results presented in this article showed that the milking season and the associated feeding ration of yaks affects the composition of milk, which is associated with the nutritional value of grass feed and its nutrient content. Spring milk contains more proteins and amino acids than summer milk, which is due to the high protein content of plants in the spring period before the flowering phase. Milk of Kyrgyz yak with proven high nutritional and biological value is an alternative to cow milk.

Modelling present and future rock wall permafrost distribution in the Sisimiut mountain area, West Greenland

Abstract. Degrading rock wall permafrost was found responsible for the increase in rockfall and landslide activity in several cold mountain regions across the globe. In Greenland, rock wall permafrost has so far received little attention from the scientific community, despite mountains being a predominant feature on the ice-free coastline and landslide activity being significant. In this study, we aim to make a first step towards a better understanding of rock wall permafrost in Greenland by modelling rock wall temperatures in the mountain area around the town of Sisimiut, which is 68° N on the west coast of Greenland. We first acquire rock surface temperature (RST) data for the period September 2020–September 2022 to model rock surface temperatures from weather forcing. The model is then applied to weather data from 1870 to 2022, generating rock surface temperatures to force transient heat transfer simulations over the same period. By extrapolating this method at the landscape scale, we obtain permafrost distribution maps and ad hoc simulations for complex topographies. Our model results are compared to temperature data from two lowland boreholes (100 m depth) and geophysical data describing frozen and unfrozen conditions across a mid-elevation mountain ridge. Finally, we use regional carbon pathway scenarios 2.6 and 8.5 to evaluate future evolution of rock wall temperatures until the end of the 21st century. Our data and simulation describe discontinuous permafrost distribution in rock walls up to roughly 400 m a.s.l. Future scenarios suggest a decline of deep frozen bodies up to 800 m a.s.l., i.e. the highest summits in the area. In summary, this study depicts a picture of warm permafrost in this area, highlighting its sensitivity to ongoing climate change.

Synoptic sampling reveals spatial stability in flow and chemistry patterns despite large seasonal variability in a subarctic mountain catchment

AbstractSeasonality plays a critical role in cold mountain regions as variation in air temperature, ground thermal status, and precipitation phase alter the rate, timing and magnitude of hydrological and chemical transport. Additionally, cold mountain catchments can have highly variable topography, geology, permafrost, and landcover, which intrinsically add to this irregularity. Understanding how external and internal variability act to control mass fluxes requires sampling at a high spatial resolution over time, which rarely occurs in cold remote regions. In this work, we conduct five snapshot sampling surveys across 34 subcatchments during the ice‐free period in Wolf Creek Research Basin (a mesoscale montane subarctic catchment) and two additional winter surveys across a subset of sites to assess the drivers of variability in stream chemistry and discharge. We sampled for specific conductance (SpC), major ions, and dissolved organic carbon (DOC) and used statistical metrics and Bayesian mixing analysis to quantify patterns of flow and chemistry across space and time. Our results indicate patterns in both flow and chemistry remain largely consistent across seasons for all solutes. However, there was weaker correlation of chemistry between sites, suggesting asynchronous behaviour within the catchment. There was evidence of increasing production of ions and DOC along the stream network during high spring flows but not during low flows. Although concentrations and flows exhibit high seasonality in subarctic mountains, this seasonal variability does not alter spatial patterns that arise from highly variable catchment characteristics.

Stability analysis and evaluation of a highway slope in the high and cold mountain area and suggestions for prevention and control

In order to ensure the stability of a rocky slope on a highway in a high cold mountainous area, this paper evaluates the stability of the right high slope in the section from K155+320 to K155+460 using the Chi Ping projection method and the fuzzy evaluation method based on game theory-cloudified object model. Firstly, the geological, geomorphological, hydrological and other natural profile information of the slope is obtained through field investigation, and these indicators are transformed into evaluation indicators for qualitative evaluation using the Chi Ping projection method. Then, the fuzzy evaluation method based on game theory-cloudified object model is used to transform the qualitative evaluation results into quantitative data, taking into account the mutual influence between different factors. The results show that the results obtained by the two evaluation methods are consistent. Finally, based on the stability analysis and evaluation results, it is proposed to use the method of clearing the surface dangerous rocks and applying active protective nets to deal with the slope problem in that area. At the same time, the slope stability analysis and evaluation method and the prevention and control suggestions provide reference for the subsequent slope governance.

Energy-carbon emission nexus in a residential building using BIM under different climate conditions: an application of multi-objective optimization

This study was carried out to investigate the impact of building insulation, a method of reducing energy consumption, on the amount of energy consumed in a building, as well as its impact on cooling and heating loads and carbon emission. A residential structure was designed in Revit, and DesignBuilder determined the cooling and heating loads, as well as the energy consumption. Under three distinct climate conditions, the impact of the environment on the energy-carbon emission nexus of residential buildings was assessed. The cold mountain climate of Koick, Slovakia; the arid desert climate of Ha’il, Saudi Arabia; and the tropical monsoon climate of Borneo, Indonesia were chosen. During the design stage, the Particle Swarm Optimization (PSO) method was used to minimize the energy consumption cost (ECC) and CO2 emissions. Over the course of 24 h, the cooling and heating loads decreased by 2.51 kW and 1.9 kW, respectively. When the two modes in Ha’il were combined, the heating load was reduced to 850 kWh and the cooling load was reduced to 650 kWh, according to the results. In Borneo, the heating load was reduced by 200 kWh, while in Koick, it was reduced by 2,000 kWh. The cooling load was reduced by 550 and 50 kWh in Borneo and Koick, respectively. This system appears to perform better in arid and hot climates in terms of both heating and cooling loads. However, energy losses in the arid and hot climate (Ha’il) are greater than in other climates. This could be due to temperature and humidity differences between the inside and outside. According to the findings of the PSO evolutionary algorithm optimization, the building can be constructed to reduce ECC by 19% by taking into account input characteristics such as Wind-to-Wall Ratio (WWR), wall, glazes, and weather conditions. This research provides useful insights into the practical application of optimization methods for reducing CO2 emissions, paving the way for more sustainable and eco-conscious architectural practices.

On Gary Snyder’s Tradaptation of <em>Cold Mountain Poems</em> and its Spiritual Salvation and Literary Enlightenment in Postwar America

On Gary Snyder’s Tradaptation of <em>Cold Mountain Poems</em> and its Spiritual Salvation and Literary Enlightenment in Postwar America

STUDY ON THE TRANSLATION STRATEGIES OF HANSHAN POEMS FROM THE PERSPECTIVE OF CROSS-CULTURAL PRAGMATICS

In Japan, Europe, the United States and other countries, Hanshan and his poems have intrigued great enthusiasm of scholars and the public. Since the 1950s, Hanshan poems have been constantly being translated and successfully spreading in the United States, which has exerted a great influence. With the continuous enhancement of the cultural soft power, China attaches great importance to the foreign translation of excellent traditional culture. The medium of translation is language, which is a cross-cultural pragmatic practice. By integrating cross-cultural pragmatics into studies of the classical poetry translation, the thinking and strategies used by translators in the process of translation can be explored in order to shed light on how to achieve cross-cultural communication goals in the future. In 1983, Songs of Cold Mountain translated by American folk scholar Red Pine is the first full English translation of the poetry. With the help of cross-cultural pragmatics, this paper analyzes the English translation strategy of Red Pine's Hanshan Poems and his handling of linguistic and cultural differences, which also provides some inspiration for Chinese literature to go out to the world and promote culture to "go global".

Ecosystem engineers in the extreme: The modest impact of marmots on vegetation cover and plant nitrogen and phosphorus content in a cold, extremely arid mountain environment.

Burrowing mammals strongly impact plant communities. One of the main effects is accelerating nutrient cycling and thus promoting plant growth. This mechanism is well-studied in grasslands and alpine habitats, but less is known about this phenomenon in arid, cold mountain environments. We studied ecosystem engineering by long-tailed marmots (Marmota caudata) by measuring the content of plant nitrogen and phosphorus, as well as nitrogen stable isotopes in plant biomass and marmot feces in a distance gradient up to 20 m from marmot burrows in an extremely arid glacier valley in Eastern Pamir, Tajikistan. We also captured aerial images of the area inhabited by marmots to study the spatial distribution of vegetation. There was a weak relationship between the presence of burrows and vegetation cover on soil not covered by burrow material. Burrow mounds were not colonized by plants, as opposed to other studies, where mounds are often microhabitats that enhance plant diversity. A significant increase in N and P in aboveground green plant biomass in the proximity of burrows was found in one out of six studied plant species. Contrary to our expectations, stable N isotopes did not give further insight into N routing. We assume that plant growth is strongly limited by water availability, which prevents them from utilizing the local increase in nutrients, certainly provided by marmot activity. The results are contrary to numerous studies, which showed that the role of burrowing animals as ecosystem engineers increases with increasing abiotic stress, including aridity. This shows a lack of this type of study at the end of the gradient of abiotic factors.

Using Borehole Temperatures for Knowledge Transfer about Mountain Permafrost: The Example of the 35-year Time Series at Murtèl-Corvatsch (Swiss Alps)

Climate-related permafrost is widespread in cold mountains and heavily affects slope stability. As a subsurface phenomenon, however, it is often still absent in the perception of key partners concerning the discussion and anticipation of long-term impacts on high mountain regions from continued global warming. Outreach and knowledge transfer, therefore, play a key role. Long-term observations of permafrost temperatures measured in boreholes can be used to convey answers and key messages concerning thermal conditions in a spatio-temporal context, related environmental conditions, affected depth ranges, and impacts of warming and degradation on slope stability.The 35-year Murtèl-Corvatsch time series of borehole temperatures from which data is available since 1987, is used here as an example. Today, mountain permafrost is well documented and understood regarding involved processes, as well as its occurrence in space and evolution in time. Thermal anomalies caused by global warming already now reach about 100 meters depth, thereby reducing the ground ice content, causing accelerated creep of ice-rich frozen talus/debris (so-called “rock glaciers”) and reducing the stability of large frozen bedrock masses at steep icy faces and peaks.

Eco-Philosophical Perspectives in the Select Poems of Gary Snyder: A critical Exposition

Eco Philosophy as a captivating branch of academic study emerged on the international theoretical scene as a viable and acknowledged field of academic inquiry, Eco-Philosophy has undergone a virtually incessant process of improvement, expansion, broadening of scope, and reworking of fundamental concepts. It began with serious nature of addressing, analysing, and understanding the essense of ecological vision and literary application. It is being followed by divergences over the correct area of study, the best theories, and the compatibility of local or national literary and critical traditions. Even the use of dialects in oral performance falls under this spectrum of study. In order to examine the various facets of Eco Philosophy as an Eco critical enquiry in the field of poetry, the poetic vision of Gary Snyder is profoundly accredited. With an intense interpretation of Snyder’s poetry, the present article deals with Snyder's idealistic vision of the relationship between human beings and the natural world. It investigates the ecological implications in his major poetic works, Riprap and Cold Mountain Poems (1959), Turtle Island (1974) and Mountains and Rivers without End (1996). An earnest attempt made to read those works from an ecological point of view to draw the attention of the readers to the significance of the environmental concerns embodied in the poetic works of Gary Snyder.

Floristic Composition and Biological Spectrum of The Bogdkhan Mountain, Mongolia

The Bogdkhan mountain of Mongolia is strictly protected and possesses a unique ecosystem, because of its location in the transitional zone of Siberian taiga and the Asian steppe. Floristic composition and the biological spectrum of the Bogdkhan Mountain were studied during July 2019 to September 2020. A total of 522 vascular plants were recorded belonging to 249 genera and 63 families. Asteraceae was found to be the most dominant family (13.22%; 33 genera and 69 taxa) followed by Poaceae (8.43%; 21 genera and 44). The classified life-form spectra of all the species recorded from the study area revealed the predominance of hemicryptophytes (63.03%) followed by geophytes (11.30%), therophytes (10.34%), phanerophytes (9.58%), chamaephytes (5.36%), and hydrophytes (0.38%). The notable changes found in the biological spectrum, which are chamaephytes from 12 to 5.36%, geophytes from 8 to 11.30% and therophytes from 8 to 10.34%. Variaty of reasons might cause change the life form, such as climate change, anthropogenic impacts, etc. Hemicryptophytes and chamaephytes dominate the flora of the mountain due to the cold mountain niche. The floristic diversity of this mountain tends to decline further videnced from the observed lesser divergence values of geophytes and therophytes. Bangladesh J. Plant Taxon. 29(2): 241-268, 2022 (December)

Body Temperature and Heart Rate Monitoring System Using Fuzzy Classification Method

Climbing becomes one of the extreme sports that test endurance with nature, just like in a mountainous environment. In addition to the excitement and fun that climbing provides, climbers enjoy the opportunity to view breathtaking natural scenery and breathe in the fresh air drawn directly from the surrounding environment. Because of the temperature in the cold mountains, there are frequent and common obstacles Not realized by the climbers, such as hypothermia. Hypothermia is a condition in which the body temperature drops below 35oC. When body temperature is below normal 37oC, nervous system function and other body organs will experience interference. If not soon Left untreated, hypothermia can lead to heart failure, disturbances respiratory system, and even death. To anticipate things requires a system that functions to know the condition of mountaineer health. The system to be created uses the Mamdani fuzzy logic method, which decides whether the climber is healthy. The fuzzy logic method is used for decision-making based on body temperature and heart rate values. Implementation of the system in the form of a prototype containing sensors and mini-computers located at the climbing post, with data transmission using a node sent from post x to the main post to be uploaded to the database so that it can be known by the admin or rescue team when climbers need help in critical situations. This is done so that the condition can be monitored.

Powertrain Design and Energy Management Strategy Optimization for a Fuel Cell Electric Intercity Coach in an Extremely Cold Mountain Area

Facing the challenge that the single-motor electric drive powertrain cannot meet the continuous uphill requirements in the cold mountainous area of the 2022 Beijing Winter Olympics, the manuscript adopted a dual-motor coupling technology. Then, according to the operating characteristics and performance indicators of the fuel cell (FC)–traction battery hybrid power system, the structure design and parameter matching of the vehicle power system architecture were carried out to improve the vehicle’s dynamic performance. Furthermore, considering the extremely cold conditions in the Winter Olympics competition area and the poor low-temperature tolerance of core components of fuel cell electric vehicles (FCEV) under extremely cold conditions, such as the reduced capacity and service life of traction batteries caused by the rapid deterioration of charging and discharging characteristics, the manuscript proposed a fuzzy logic control-based energy management strategy (EMS) optimization method for the proton exchange membrane fuel cell (PEMFC), to reduce the power fluctuation, hydrogen consumption and battery charging/discharging times, and at the same time, to ensure the hybrid power system meets the varying demand under different conditions. In addition, the performance of the proposed approach was investigated and validated in an intercity coach in real-world driving conditions. The experimental results show that the proposed powertrain with an optimal control strategy successfully alleviated the fluctuation of vehicle power demand, reduced the battery charging/discharging times of traction battery, and improved the energy efficiency by 20.7%. The research results of this manuscript are of great significance for the future promotion and application of fuel cell electric coaches in all climate environments, especially in an extremely cold mountain area.

Live Broadcast from India's Favorite News Channel

Live Broadcast from India's Favorite News Channel Bhavika Sicka (bio) He was beatenshe was groped they were both beaten werebeaten her kurta ripped hishead on the pavement hewasbeaten then shot surrounded by students of Nehru University students shouting protesting anti-nationals running through tear gas with banners, barricades blocking barricading thestreets the campus cordonedoff its rowdies cordonedoff police keeping students incheck in checkchecking the violence the prime minister laments thelack ofdiscipline says universities are todiscipline yet our universities are failing what doyou think? Tweet with hashtag universitiesarefailing keep watching for updates we have beenvoted the best newschannel again and coming up Sushmita Sen is dating Lalit Modi followourchannel for more! [End Page 134] Bhavika Sicka Bhavika Sicka is a Kutchi Gujarati writer and educator from Kolkata, India, settled in Norfolk, USA. She has been a finalist for the Times of India's 'Write India' contest and a recipient of the Dickseski Fiction Prize awarded by Old Dominion University. Her writings have appeared or are forthcoming in Beltway Poetry Quarterly, Cold Mountain Review, Lunch Ticket, Arkana, Waxwing, and Hunger Mountain, among other journals. Copyright © 2022-2023 Pleiades and Pleiades Press

Frost cracking dictated landslide distribution in response to temperature change since Last Glacial Maximum across the Eastern Qilian Mountains

AbstractTemperature‐dependent frost cracking is a major weathering process that dominates sediment supply and hillslope erosion by reducing shear strength and conditioning slopes to be more failure‐prone in cold mountain regions. Landslides are a common erosional process in such landscapes. The linkage between these two processes has been proposed but many of the mechanisms remain to be investigated. In this study we compile a landslide inventory in the Eastern Qilian Mountains including 2482 rockfalls and 5373 elongate transport zone footprints. We use a widely accepted frost cracking model to explore this weathering process as a mechanism of paleoclimate control on the modern landslide distribution. The results show that landslides concentrate in a narrow altitudinal range and that this elevation dependence varies with slope aspect. Based on the paleoclimate record, we calculate the time‐averaged frost cracking intensity (Fci) since Last Glacial Maximum (LGM) and adopt different parameters for two slope aspects. We find that time averaged Fci is a good predictor of the landslide elevation distribution for both aspects. We then introduce two slope‐based landslide initiation and runout models (i.e., SHALRUN and FCIRUN) to examine the relative roles of slope versus temperature in determining the landslide probability in space. The FCIRUN model, which incorporates Fci as a measure of sediment supply, consistently outperforms the SHALRUN model. This result suggests that frost cracking determines the pattern of landslide initiation, although topography still controls their runout path. Our study highlights the potential of introducing Fci into slope‐based landslide prediction models to improve model skill in identifying hazardous areas (e.g., rockfall) across weathering‐limited landscapes like the Qilian Mountains.

“The Real Work”: Gary Snyder’s Early Poetic Journey From “Cold Mountain Poems” to “Riprap”

“The Real Work”: Gary Snyder’s Early Poetic Journey From “Cold Mountain Poems” to “Riprap”

Natural Trap Cave tephra correlation to Yellowstone using U-series (230Th/238U) dates and oxygen isotopes of zircon and chemical composition of adherent glass

Zircon crystals from ash layers intercalated with fossil-rich sediment from Natural Trap Cave (NTC) in Wyoming (USA) were investigated to refine the chronostratigraphy of this unique late-Quaternary megafaunal assemblage. Glass compositions of individual glass spicules and glass adherent to zircon along with a characteristic low-δ18O signature of zircon (on average + 2.4‰ relative to Vienna standard mean ocean water) indicate tephra provenance from post-Lava Creek Tuff activity of Yellowstone. Yellowstone glass composition was hence used to anchor the 230Th/238U zircon isochron and to compute model crystallization ages, which translate into maximum depositional ages. For the lowermost visible tephra layer in new excavations in NTC strata, an upper age limit of 138 ± 9 ka (1σ age uncertainty) was thus obtained. A younger tephra with a230Th/238U zircon date of 111 ± 8 ka is tentatively correlated with Tuff of Cold Mountain Creek from the Central Plateau Member of Yellowstone, suggesting a minor lag time between zircon crystallization and eruption. The NTC tephra record thus has high potential for refining the explosive volcanic history and tephra distribution patterns of Yellowstone during the late Pleistocene.