Snowy Mountains Research Articles

Hydrology Outweighs Temperature in Driving Production and Export of Dissolved Carbon in a Snowy Mountain Catchment

AbstractTerrestrial production and export of dissolved organic and inorganic carbon (DOC and DIC) to streams depends on water flow and biogeochemical processes in and beneath soils. Yet, understanding of these processes in a rapidly changing climate is limited. Using the watershed‐scale reactive‐transport model BioRT‐HBV and stream data from a snow‐dominated catchment in the Rockies, we show deeper groundwater flow averaged about 20% of annual discharge, rising to ∼35% in drier years. DOC and DIC production and export peaked during snowmelt and wet years, driven more by hydrology than temperature. DOC was primarily produced in shallow soils (1.94 ± 1.45 gC/m2/year), stored via sorption, and flushed out during snowmelt. Some DOC was recharged to and further consumed in the deeper subsurface via respiration (−0.27 ± 0.02 gC/m2/year), therefore reducing concentrations in deeper groundwater and stream DOC concentrations at low discharge. Consequently, DOC was primarily exported from the shallow zone (1.62 ± 0.96 gC/m2/year, compared to 0.12 ± 0.02 gC/m2/year from the deeper zone). DIC was produced in both zones but at higher rates in shallow soils (1.34 ± 1.00 gC/m2/year) than in the deep subsurface (0.36 ± 0.02 gC/m2/year). Deep respiration elevated DIC concentrations in the deep zone and stream DIC concentrations at low discharge. In other words, deep respiration is responsible for the commonly‐observed increasing DOC concentrations (flushing) and decreasing DIC concentrations (dilution) with increasing discharge. DIC export from the shallow zone was ~66% of annual export but can drop to ∼53% in drier years. Numerical experiments suggest lower carbon production and export in a warmer, drier future, and a higher proportion from deeper flow and respiration processes. These results underscore the often‐overlooked but growing importance of deeper processes in a warming climate.

STRATEGIC IMPORTANCE OF ANCIENT INDIAN MARITIME POWER

India is a peninsular country bounded by the lofty Himalayas in the north, is surrounded by oceans and seas on three sides and has a 7,517 km long coastline. The Indian Ocean engulfs the country in its South. It has recently re-emerged as a sphere of power politics in International Relations. The following slok of Vishnu Purana illustrates the Geo-Strategic importance of Bharat.उत्तरं यत् समुद्रस्य हिमाद्रेश्चैव दक्षिणम् |वर्षं तद् भारतं नाम भारती यत्र सन्ततिः || विष्णु पुराण २.३.१The country that lies north of the ocean and south of the snowy mountains is called Bhāratam, there dwells the descendants of Bharat.China is in India’s backyard, an expansionist and imperialist power challenging the aspects of maritime security in the region, and Pakistan is a hostile neighbour, it is high time that a comprehensive framework of India’s maritime security is developed. As an ancient civilisation, the country has a rich legacy of its naval prowess. The civilisational culture from the ancient land of Bharat spread worldwide, especially in Southeast Asian, African, Central Asian, and East Asian countries through the Indian Ocean. The Indian Ocean, therefore, is not merely a waterbody. Instead, it captures the essence of India’s religion and cultural wave, transcending even to the neighbouring countries. India's history, art, mythology and literature are replete with numerous instances of the importance of the Indian Ocean in the lives of the Indian people. The cultural depth of the Indian civilisation is as deep as the Indian Ocean. Therefore, this article argues about the strategic relevance of ancient India’s maritime diplomacy.

Developmental characteristics of an inverted trapezoidal glacial valley and its influencing factors in the Geladandong snowy mountain

Developmental characteristics of an inverted trapezoidal glacial valley and its influencing factors in the Geladandong snowy mountain

Aesthetics and symbolic meaning of ancient Chinese snowy landscapes from the IV to the XX century.

The article examines the aesthetic and symbolic aspects of ancient Chinese snowy landscapes, covering the period from the IV to the XX century. The focus of the research is Guohua painting, representing classic snowy landscapes, compositions with birds and flowers, as well as snow portraits. An in-depth analysis of the symbolism and meaning of elements such as "four seasons", "snow", "snowy mountains", "three friends of cold time" and "cold beasts" was carried out, as well as the narrative characteristics of snowy landscapes were studied. It was revealed that snow scenes reflect the vitality and stability of a person, causing reflections on life difficulties. The work highlights how snowy landscapes have become a means of expressing emotions, reflecting sadness, but also demonstrating strength, well-being, morality and the sublimity of cultural values. The study uses the methodology of symbolism and iconology analysis to study the aesthetics of ancient Chinese snowy landscapes. A comparative approach is applied to various eras and techniques, including ink painting and engraving, to assess the cultural and emotional meanings of snow in Chinese art. The research touches on a rarely covered topic in the history of art — the aesthetic and symbolic depth of ancient Chinese snowy landscapes, from the IV to the XX century. Introducing into scientific discourse a deep analysis of changes in the perception and image of snow, the work presents a comprehensive study using iconology and semiotics to uncover hidden meanings in Chinese Guohua painting. She reveals how artists have reflected the emotional and philosophical aspects of life through snowy landscapes, demonstrating their influence on cultural representations of nature, man and society. The innovation of the study lies in the fact that it connects the aesthetic elements of snow with cultural and historical changes in China, showing their importance for understanding Chinese identity and aesthetic perception. This study not only enriches the academic understanding of Chinese painting, but also highlights the layering of symbols and metaphors in traditional art, reflecting a unique combination of natural phenomena and cultural meanings.

Quality of Cardiopulmonary Resuscitation in Avalanche Victims with a Single Rescuer: A Prospective, Crossover, Manikin Pilot Study.

Tanaka, Shota, Koshi Nakagawa, Yosuke Kanagawa, Takashi Katsurahara, Kazuki Kozakai, Ken Tsuhako, Fumitaka Yoshikawa, Soh Gotoh, Kensuke Osanai, Madoka Sono, Hironori Inoue, Shuji Sakanashi, Hiroyuki Takahashi, and Hideharu Tanaka. Quality of cardiopulmonary resuscitation in avalanche victims with a single rescuer: a prospective, crossover, manikin pilot study. High Alt Med Biol. 25:60-67, 2024. Background: Winter outdoor recreational activities such as off-piste skiing have gained popularity and, as a result, the number of avalanche-related deaths has increased. However, the quality of cardiopulmonary resuscitation (CPR) at avalanche sites remains unclear. Our study compared the quality of CPR performed in a simulated avalanche burial on a snowy mountain with that performed indoors. Methods: Ten prehospital health care providers participated in the crossover pilot study. Various methods, including over-the-head CPR (OTH-CPR) and standard CPR, were used to perform avalanche resuscitation, with five rescue breaths, followed by 30 chest compressions and two breaths. The quality CPR was judged by four variables of chest compression and ventilation. Results: The OTH-CPR performed indoors was better in quality: 5.33% [95% confidence interval (CI) -14.2 to 3.5] higher in adequate compression depth (94.3 ± 10.6% on the snow vs. 99.3 ± 1.1% indoors), 3.4% [95% CI -16.1 to 22.9] higher in adequate compression rate (70.4 ± 38.0% vs. 76.1 ± 35.7%), and 2.3% [95% CI -6.4 to 1.72] higher in adequate recoil (96.9 ± 4.8% vs. 99.2 ± 1.6%) than OTH-CPR on the snow. In terms of ventilation quality, OTH-CPR performed indoors had a 50% higher ventilation score [95% CI -73.0 to -27.0] than OTH-CPR on the snow (1.4 ± 4.3% vs. 45.9 ± 32.6%, Cohen's d = -1.81). Conclusions: Chest compression quality was slightly impaired in the avalanche scenarios on the snow than in indoor settings. Asphyxiation is the main cause of avalanche-related deaths; however, low ventilation quality was observed on snow compared with the indoor setting.

Hamlet at the Himalayan Border: Frontier Imaginaries in Hu Xuehua’s Prince of the Himalayas and Vishal Bhardwaj’s Haider

ABSTRACT This article discusses Hu Xuehua’s Prince of the Himalayas (2006) and Vishal Bhardwaj’s Haider (2014) across overlapping local, regional and (inter)national imaginaries of Tibet and Kashmir, and considers the possibilities of rendering the story and circumstances of Hamlet legible within these borderland contact zones. With their exotic backdrop of snowy mountains, rugged frontiers and majestic rivers, these two films can be seen recreating a troubling politics of appropriation at a time of renewed tensions in the Himalayan region. I argue that despite using Shakespeare’s cultural capital to depict local conditions and affirm their own political agency, Hu and Bhardwaj’s ultimate rejection of Hamlet’s revenge motif continue to challenge domestic and international viewers, particularly in their attempts to situate these films within a heterogeneous national cinema encompassing minority cultures in New Chinese Cinema and Bollywood respectively.

Microphysical mechanisms of wintertime postfrontal precipitation enhancement over the Australian Snowy Mountains

AbstractA heavy orographic precipitation event associated with the postfrontal sector of a midlatitude cyclone over the Australian Snowy Mountains (ASM) was analyzed using field observations and numerical simulations. This event, observed during a 2018 intensive field campaign, was of particular interest as three distinct precipitation episodes were identified within a prolonged postfrontal period. Deep mixed‐phase clouds (MPCs) characterized by cold cloud‐top temperatures (colder than −30°C) and the presence of updrafts extending 3.5–4.5 km above the boundary‐layer height, produced the three enhanced precipitation events over the windward slopes of the ASM. The presence of conditional instabilities and deep updrafts were also found in the sounding and Doppler velocity observations respectively, while the cloud radar observations show the deep MPCs with cloud tops reaching to 6–7 km a.s.l. Orographic convection invigoration was found to be the main mechanism producing the precipitation enhancement over the windward slopes and higher terrain. Using the Weather Research/Forecasting model, we analyzed the rates of microphysical processes to explicitly account for the enhancement of precipitation formation processes in these MPCs. This analysis showed that the precipitation formation processes were further enhanced through depositional and riming growth of ice‐phase hydrometeors during the three precipitation events. Deposition is simulated at higher levels (above the −15°C level) and most likely enabled by deep convective updrafts through the midtroposphere, whereas riming is stronger at lower levels (below −10°C level) due to the persistent production of feeder supercooled liquid water clouds sustained by the orographic lifting.

Братья Степан и Иван Кондурушкины

The article highlights the hitherto understudied connection between the biography and literary activity of law enforcement officer of Soviet Russia Ivan Kondurushkin and the work of his brother, writer Stepan Kondurushkin. The research partially reconstructs Ivan’s writing fate, which began with the mediation of his brother back in pre-revolutionary times in collaboration with the children’s magazine “Tropinka.” The article raises the question about the relationship between the literary heritage of the Kondurushkin brothers and the fact of inclusion of Stepan’s works in Ivan’s collection of stories “In the Snowy Mountains” (1930). The literary fate of the story “Gandeikin’s Life” (1909), republished in 1930 under the title “Vanka the Prisoner,” is examined in detail. Analysis of the work by Ivan reveals that the facts of the biography of the writer’s brother, Stepan Kondurushkin, formed the basis of the story of the main character. The article provides a comparative analysis of two editions of the story by Ivan, reveals elements of autobiography in the story “Vanka Prison,” and emphasizes the author’s changes in social aspects according to the new socio-political situation in Russia. The conclusion emphasizes that the presence of brother’s texts in Ivan’s literary work creates difficulties in determining the author of a particular story, which allows us to formulate as a scientific problem the question of determining the authorship of some texts of the Kondurushkin brothers.

The Alteration of Flood Peak Discharge by Land Cover Change in Prek Thnot Watershed, Kampong Speu Provine, Cambodia

This study analyses the alterations of peak catchment runoff from Prek Thnot watershed using the Soil Conservation Service Curve Number (SCS-CN) methodology. Two major studies using different approaches have previously been conducted in the catchment, albeit producing inconsistent results. The Snowy Mountain Hydro-electric Authority published the first study in 1967 and found that the peak surface flow runoff over a 10-year return period was 710 m3/s. The second study was conducted by the Japanese International Cooperation Agency (JICA) between 1991 and 2006 and reported a peak catchment discharge of 1,380 m3/s. To date, there has been no discussion comparing the two studies to determine why the discharge during the later study was double that of the first. As the annual rainfall during the two study periods was similar, it is suggested that this discrepancy may be attributed to physical changes in the watershed, such as changes to forest cover. We deployed the Hydrologic Engineering Centre-Hydrologic Modeling System to simulate the peak runoff of the catchment. Our result was very similar to the JICA finding. Our data suggested that the increase in catchment discharge may be attributed to the conversion of 26% of forest cover in the catchment to agricultural land since the early 2000s. This information is useful for flood management practices, particularly with respect to managing catchment runoff in the context of rapid deforestation and the hydrological impacts of climate change within the watershed. The paper analyzes the impact of land-use changes on catchment runoff and provides valuable insights for flood management practices in the context of climate change and deforestation.

Simulating Wintertime Orographic Cloud Seeding over the Snowy Mountains of Australia

Abstract This study presents the first numerical simulations of seeded clouds over the Snowy Mountains of Australia. WRF-WxMod, a novel glaciogenic cloud-seeding model, was utilized to simulate the cloud response to winter orographic seeding under various meteorological conditions. Three cases during the 2018 seeding periods were selected for model evaluation, coinciding with an intensive ground-based measurement campaign. The campaign data were used for model validation and evaluation. Comparisons between simulations and observations demonstrate that the model realistically represents cloud structures, liquid water path, and precipitation. Sensitivity tests were performed to pinpoint key uncertainties in simulating natural and seeded clouds and precipitation processes. They also shed light on the complex interplay between various physical parameters/processes and their interaction with large-scale meteorology. Our study found that in unseeded scenarios, the warm and cold biases in different initialization datasets can heavily influence the intensity and phase of natural precipitation. Secondary ice production via Hallett–Mossop processes exerts a secondary influence. On the other hand, the seeding impacts are primarily sensitive to aerosol conditions and the natural ice nucleation process. Both factors alter the supercooled liquid water availability and the precipitation phase, consequently impacting the silver iodide (AgI) nucleation rate. Furthermore, model sensitivities were inconsistent across cases, indicating that no single model configuration optimally represents all three cases. This highlights the necessity of employing an ensemble approach for a more comprehensive and accurate assessment of the seeding impact. Significance Statement Winter orographic cloud seeding has been conducted for decades over the Snowy Mountains of Australia for securing water resources. However, this study is the first to perform cloud-seeding simulation for a robust, event-based seeding impact evaluation. A state-of-the-art cloud-seeding model (WRF-WxMod) was used to simulate the cloud seeding and quantified its impact on the region. The Southern Hemisphere, due to low aerosol emissions and highly pristine cloud conditions, has distinctly different cloud microphysical characteristics than the Northern Hemisphere, where WRF-WxMod has been successfully applied in a few regions over the United States. The results showed that WRF-WxMod could accurately capture the clouds and precipitation in both the natural and seeded conditions.

An Analysis of Hemingway’s Symbolism in the Snow of Kilimanjaro

This paper analyzes the symbolic meaning of Hemingway’s well-known short story The Snow of Kilimanjaro based on symbolism theory, which makes readers better understand the Hemingway’s powerful creation of character and his unique language style. This paper analyzes the images of snowy mountains, snow in memory, leopards, wine, gangrene and their relations with Harry, and explains their symbolic meanings in the novel. Although images such as wine and gangrene imply that Harry's death is too heavy, the snow mountain of Kilimanjaro and the leopard symbolize Harry's spiritual immortality.

Runoff Mechanism in the Source Basin of the Snowy Mountains Consisting of the Hida Metamorphic Rock

Runoff Mechanism in the Source Basin of the Snowy Mountains Consisting of the Hida Metamorphic Rock

Transforming Inner Alchemical Vision into Painting: Huang Gongwang’s Clearing after Sudden Snow

This paper argues that the Yuan dynasty Daoist Huang Gongwang’s 黃公望 (1269–1354) painting Clearing after Sudden Snow resonates with the principles of inner alchemy (neidan, 內丹), particularly the stage known as the resurgence of yang force. Within this painting, four prominent visual elements—the sun, the spirit room, the cliff, and the snowy mountains—come together to imbue the painting with a rich tapestry of inner alchemical connotations. They collectively portray the sequential stages of cultivation, refinement, and transformation in the context of inner alchemy. The painting not only captures the moment of transition where the snow-covered terrain is gradually transforming into a fresh and awakened state, but it also embodies a visual metaphor for the inner alchemical transformative journey. Furthermore, each individual who engages with the painting may undergo their own personal transformation through the act of contemplation and reflection.

Observed and projected changes in snow accumulation and snowline in California’s snowy mountains

The Sierra Nevada and Southern Cascades—California’s snowy mountains—are primary freshwater sources and natural reservoirs for the states of California and Nevada. These mountains receive precipitation overwhelmingly from wintertime storms including atmospheric rivers (ARs), much of it falling as snow at the higher elevations. Using a seven-decade record of daily observed temperature and precipitation as well as a snow reanalysis and downscaled climate projections, we documented historical and future changes in snow accumulation and snowlines. In four key subregions of California’s snowy mountains, we quantified the progressing contribution of ARs and non-AR storms to the evolving and projected snow accumulation and snowlines (elevation of the snow-to-rain transition), exploring their climatology, variability and trends. Historically, snow makes up roughly a third of the precipitation affecting California’s mountains. While ARs make up only a quarter of all precipitating days and, due to their relative warmth, produce snowlines higher than do other storms, they contribute over 40% of the total seasonal snow. Under projected unabated warming, snow accumulation would decline to less than half of historical by the late twenty-first century, with the greatest snow loss at mid elevations (from 1500 to 3300 m by the mountain sub-regions) during fall and spring. Central and Southern Sierra Nevada peaks above 3400 m might see occasionally extreme snow accumulations in January–February resulting entirely from wetter ARs. AR-related snowlines are projected to increase by more than 700 m, compared to about 500 m for other storms. We discuss likely impacts of the changing climate for water resources as well as for winter recreation.

Transcriptomic evidence indicates that montane leaf beetles prioritize digestion and reproduction in a sex-specific manner during emergence from dormancy

During winter, many organisms conserve resources by entering dormancy, suppressing metabolism and biosynthesis. The transition out of winter dormancy to summer activity requires a quick reversal of this suppression, in order to exploit now-favorable environmental conditions. To date, mechanisms by which winter climate variation affects this transition remains unelucidated. Here we experimentally manipulated snow cover for naturally overwintering montane leaf beetles (Chrysomela aeneicollis), and profiled changes in gene expression during the transition out of dormancy in spring. Upon emergence, beetles up-regulate transcripts associated with digestion and nutrient acquisition and down regulate those associated with lipid metabolism, suggesting a shift away from utilizing stored lipid and towards digestion of carbohydrate-rich host plant tissue. Development of digestive capacity is followed by up-regulation of transcripts associated with reproduction; a transition that occurs earlier in females than males. Snow manipulation strongly affected the ground thermal regime and correspondingly gene expression profiles, with beetles showing a delayed up-regulation of reproduction in the dry compared to snowy plots. This suggests that winter conditions can alter the timing and prioritization of processes during emergence from dormancy, potentially magnifying the effects of declining snow cover in the Sierra's and other snowy mountains.

The effect of the introduction of livestock on the erosion of alpine soils: a comparison of five dating techniques applied to sediments of the Australian alpine Blue Lake

210Pb and 137Cs dating of bulk sediments obtained from the alpine Blue Lake, located in the Snowy Mountains of southeastern Australia, was applied here to date recent lacustrine sediments. In addition, the presence of Pinus pollen (a taxon introduced in Australia about 150 years ago) down to a sediment depth of 56 cm in the core is used to obtain a chronology for the upper part of the core. Accelerated Mass Spectrometry radiocarbon dates obtained from organic muds from the same core do not agree with the chronology constructed using the three other dating techniques. In addition, optically stimulated luminescence (OSL) dating of single quartz grains, from sediment-core samples collected from the same lake, was applied to date recent lacustrine sediments. The optical age of 185 ± 20 years for a sample at 60–62 cm depth, and 470 ± 50 years at 116–118 cm depth are well over 1000 years younger than the ages inferred from radiocarbon dates. We therefore infer that the ‘old’ radiocarbon ages result from carbon stored for considerable time within the catchment prior to its transport and deposition on the lake floor. As plant decomposition occurs at much slower rates in high altitude environments, these results bring into question the veracity of previously published radiocarbon dates from Blue Lake and alpine lake sediments in general. The deposition ages inferred from the 210Pb-137Cs and OSL dating, and the first appearance of Pinus pollen, indicate that for the 100-year period after European settlement (from the mid 1800s to early 1900s) the sediment-accumulation rate increased by a factor of about 2, from 0.19 ± 0.01 cm yr−1 to 0.35 ± 0.02 cm yr−1. In the 1900s the accumulation rate increased further to 0.60 cm yr−1. The accumulation rate was particularly rapid in the 20-year period from 1940–1960, reaching a rate 18 times higher than the pre-European rate in the mid-1950s. The increase in sedimentation rate is attributed to changes in land use resulting from European activities in the lake catchment, primarily through sheep and cattle grazing in the Blue Lake catchment.

A new species of Tasmanian mountain shrimp, Anaspides driesseni sp. nov. (Malacostraca, Anaspidacea, Anaspidesidae)

Species of the genus Anaspides, known as mountain shrimps, are endemic to Tasmania and inhabit a variety of freshwater habitats such as mountain tarns, pools, creeks and runnels, as well as caves. Until 2015 only two species of Tasmanian mountain shrimps were recognized, A. tasmaniae (Thomson, 1893), which was believed to be widespread all over the island and A. spinulae from Lake St. Clair. Revision of the genus by Ahyong in 2016 recognized 7 species, most having narrow geographic distributions. Only two widespread species remained: A. richardsoni, occurring mainly on the Central Plateau and its margins, and A. swaini, occurring largely in south-western Tasmania. Notably, within A. swaini, three geographically correlated morphological forms were observed. We re-evaluated all three forms of A. swaini and herein describe one of the forms as a new species, A. driesseni, on the basis of morphological and molecular data. Anaspides driesseni corresponds to A. swaini form 3 and occurs mainly in south-eastern Tasmania from the Hartz Mountains over the Snowy Mountains to the Wellington Range. Telson structure, spination and male secondary sexual characters proved taxonomically instrumental.

Plant species richness prediction from DESIS hyperspectral data: A comparison study on feature extraction procedures and regression models

The diversity of terrestrial vascular plants plays a key role in maintaining the stability and productivity of ecosystems. Monitoring species compositional diversity across large spatial scales is challenging and time consuming. Airborne hyperspectral imaging has shown promise for measuring plant diversity remotely, but to operationalise these efforts over large regions we need to advance satellite-based alternatives. The advanced spectral and spatial specification of the recently launched DESIS (the DLR Earth Sensing Imaging Spectrometer) instrument provides a unique opportunity to test the potential for monitoring plant species diversity with spaceborne hyperspectral data. This study provides a quantitative assessment on the ability of DESIS hyperspectral data for predicting plant species richness in two different habitat types in southeast Australia. Spectral features were first extracted from the DESIS spectra, then regressed against on-ground estimates of plant species richness, with a two-fold cross validation scheme to assess the predictive performance. We tested and compared the effectiveness of Principal Component Analysis (PCA), Canonical Correlation Analysis (CCA), and Partial Least Squares analysis (PLS) for feature extraction, and Kernel Ridge Regression (KRR), Gaussian Process Regression (GPR), and Random Forest Regression (RFR) for species richness prediction. The best prediction results were r=0.76 and RMSE=5.89 for the Southern Tablelands region, and r=0.68 and RMSE=5.95 for the Snowy Mountains region. Relative importance analysis for the DESIS spectral bands showed that the red-edge, red, and blue spectral regions were more important for predicting plant species richness than the green bands and the near-infrared bands beyond red-edge. We also found that the DESIS hyperspectral data performed better than Sentinel-2 multispectral data in the prediction of plant species richness. Our results provide a quantitative reference for future studies exploring the potential of spaceborne hyperspectral data for plant biodiversity mapping.

Simulation of Heavy Precipitation and the Production of Graupel Related to the Passage of a Cold Front over the Australian Snowy Mountains

Abstract The case study of a heavy precipitation event associated with the passage of cold front over the Australian Snowy Mountains (ASM) on 3 August 2018 has been examined using the observational data from an intensive field campaign and high-resolution (1 km) Weather Research and Forecasting (WRF) simulation. We divided this event into prefrontal, cold front, and postfrontal periods. The cold front and postfrontal periods were characterized by higher production of graupel, while relatively low graupel was produced in the prefrontal period. Overall, aggregation along with deposition are likely the main growth mechanisms of snow in the prefrontal clouds, while heavy rain was produced below the melting level over windward slopes of the ASM. The simulated melting level is lower compared to the observations, which is consistent with model cold bias. Stronger orographic uplift and frontal forcing were mainly responsible for the enhanced supercooled liquid water (SLW) production over the ASM in the cold front period. A drop in elevation of the freezing level and increase in low-level relative humidity further enhanced the SLW production. The production of graupel through riming processes was highly efficient in the cold front period given the high concentration of ice-phase hydrometeors in the frontal clouds and the development of clouds comprising supercooled liquid water. The orographic updrafts and embedded convection were the main dynamical processes generating postfrontal SLW clouds and graupel. Ice initiation processes were activated once SLW cloud tops reached −15°C level followed by graupel production through riming processes.

On the Detection of Snow Cover Changes over the Australian Snowy Mountains Using a Dynamic OBIA Approach

This study detected the spatial changes in Snow Cover Area (SCA) over the Snowy Mountains in New South Wales, Australia. We applied a combination of Object-Based Image Analysis (OBIA) algorithms by segmentation, classification, and thresholding rules to extract the snow, water, vegetation, and non-vegetation land covers. For validation, the Maximum Snow Depths (MSDs) were collected at three local snow observation sites (namely Three Mile Dam, Spencer Creek, and Deep Creek) from 1984 to 2020. Multiple Landsat 5, 7, and 8 imageries extracted daily MSDs. The process was followed by applying an Estimation Scale Parameter (ESP) tool to build the local variance (LV) of object heterogeneity for each satellite scene. By matching the required segmentation parameters, the optimal separation step of the image objects was weighted for each of the image bands and the Digital Elevation Model (DEM). In the classification stage, a few land cover classes were initially assigned, and three different indices—Normalized Differential Vegetation Index (NDVI), Surface Water Index (SWI), and a Normalized Differential Snow Index (NDSI)—were created. These indices were used to adjust a few classification thresholds and ruleset functions. The resulting MSDs in all snow observation sites proves noticeable reduction trends during the study period. The SCA classified maps, with an overall accuracy of nearly 0.96, reveal non-significant trends, although with considerable fluctuations over the past 37 years. The variations concentrate in the north and south-east directions, to some extent with a similar pattern each year. Although the long-term changes in SCA are not significant, since 2006, the pattern of maximum values has decreased, with fewer fluctuations in wet and dry episodes. A preliminary analysis of climate drivers’ influences on MSD and SCA variability has also been performed. A dynamic indexing OBIA indicated that continuous processing of satellite images is an effective method of obtaining accurate spatial–temporal SCA information, which is critical for managing water resources and other geo-environmental investigations.