Snow avalanches in snowy regions can become natural disasters when their flow paths intersect settlement areas or affect infrastructures. Hazard maps indicating avalanche runout areas can assist in decision-making to mitigate avalanche damage. Avalanche simulators can predict runout areas but require uncertain input variables, such as initial flow thickness and basal friction parameters. This study represents the uncertainty of input variables using probability distributions based on meteorological and snowpack measurements, and delineates hazardous regions with exceedance probabilities. By combining these distributions with a simulator, a probability map was created. The exceedance probabilities represent the likelihood of the simulator output (e.g., maximum flow thickness) exceeding a threshold value, and the probability map shows its spatial distribution. As probabilistic evaluations require a large number of numerical simulations, a polynomial emulator based on the polynomial chaos quadrature method was developed and validated for specific cases. We targeted a specific release area and assumed probability distributions based on data from an automated weather station near the release area. The probability maps, obtained using three different input probability distributions assumed for distinct cases, demonstrated that the input distributions influence both the probability values and runout zones. Sensitivity analyses identified influential input variables for each case. The simulated hazardous areas under appropriate input conditions correspond well to observed runout areas of a historical avalanche. Additionally, temporal variations in probability maps, which account for snow conditions, provide dynamic assessments of hazardous areas based on daily snowpack conditions.

Our research is aimed at improving the prediction accuracy of avalanches caused by the stability of snow cornices developed by blowing snow in the Niseko region, one of Japan's international ski resorts. For this purpose, several studies were conducted in cooperation with local authorities and ski resorts in the Niseko region. Specifically, a network of anemometers was installed and a system was developed to estimate areal wind conditions and snow redistribution over the entire mountain area from wind observation data. To validate the developed system, the snow cover distribution over the entire mountain area for two winters was obtained by laser survey using an aircraft. In addition, several portable ultrasonic anemometers were installed on the slopes where snow cornices develop to observe detailed wind conditions, and small LiDAR was used to continuously survey snow cornice development. We sampled snow in the developing snow cornice and analyzed its microstructure using X-ray computed tomography imaging. The presentation presents a first analysis.

Field evidence has confirmed a new sea salt aerosol (SSA) source on sea ice, which may significantly affect polar boundary layer chemistry and polar winter climate. While the SSA production rate from blowing snow has been previously parameterised (Yang et al., 2008) and then validated by measurements at both Poles, some key parameters involved are not yet fully constrained, leading to uncertainties when using numerical models to compare with field measurements and assess their environmental and climate impacts. In this presentation, we focus on two key parameters: blowing snow size distribution and snow salinity, which determine SSA production in number and size, respectively. We aim to constrain these factors using the latest field data, supported by remote sensing BrO data and modelling. Blowing snow particles typically follow a two-parameter gamma distribution function with shape factor (alpha) and scaling factor (beta) varying over a large range. However, our recent work focusing on the Arctic Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition data showed that at a given height, beta values increase with wind speeds, while alpha gradually approach a constant value of 1.9 at higher wind speeds (e.g. larger than 10 m/s). This is the first time that we derive such a relationship for blowing snow, which further affirms the aerosol production mechanism from blowing snow and helps elucidate the underlying processes involved. Accordingly, we parameterised the blowing snow particle size distribution as a function of wind speed, accounting for variable wind speeds during storms. In addition, supported by a chemistry transport model (p-TOMCAT), we examined the sensitivities of SSA mass and reactive bromine release rate (in association with the SSA production) to representative snow salinities derived from observations in the central Arctic and coastal regions (at Eureka, Canada). Mean winter/springtime snow salinities that best represent the Arctic were derived by comparing the modelled BrO with ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) and air-based satellite-based GOME-2 BrO data at Svalbard and Eureka.

In the polar regions, there is significant model bias in the number concentrations and seasonality of sea salt aerosol (SSA) due to the lack of understanding of aerosol sources associated with sea ice, which is hampering accurate climate forecasts at high latitudes. Recently, SSA originating from the sublimation of blowing snow has been directly observed to be an important source of aerosol particles in the Antarctic during winter/spring, validating a mechanism proposed a decade ago. Here, we report in situ observations of coarse aerosol production (particle diameter 0.5–20.0 µm) dominated by sea salt from blowing snow above sea ice during winter/spring in the Central Arctic during the MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition from October 2019 to September 2020. Blowing snow conditions occurred 20–40% of the time during each of the months from December 2019 to April 2020, with a total of 26 blowing snow events. During blowing snow periods, coarse aerosol number concentrations increased often by an order of magnitude compared to no-blowing snow periods. Mass fractions of sodium chloride in sub-micron aerosol (particle diameter 0.01–0.625 µm) available during December 2019 and 10 m wind speed showed a significant correlation (R = 0.61, P < 0.05), indicating that much of the aerosol observed during storms is sea salt released by sublimating blowing snow. We use these observations to refine the current model parameterization by considering the spatial and temporal variability of atmospheric and sea ice conditions. Snow particle size distributions and snow salinities are expressed as a function of wind speed and snowpack depth, respectively, which can be easily implemented into climate models. Validation of the snow particle size distribution parameterization with previous polar winter observations showed agreement in the Arctic (N-ICE2015 cruise, March 2015) above the threshold for drift and blowing snow, but a negative bias in the Antarctic (Weddell Sea, June to August 2013). Updating the blowing snow mechanism in the chemical transport model p-TOMCAT with wind-dependent snow particle size distributions results in 14% more SSA produced and a slightly better correlation with MOSAiC observations of coarse aerosol (R = 0.28). Significant increases in aerosol number concentration due to blowing snow sublimation are calculated by as much as 70 cm−3 during the Antarctic winter and 50 cm−3 during the Arctic winter compared to a baseline simulation with no blowing snow. Thus, taking into account SSA from blowing snow above sea ice will be important to improve model predictions of polar aerosol and climate.

Introduction Food protein-induced enterocolitis syndrome (FPIES) exhibits delayed onset of severe intestinal symptoms and may reach hypotension. Despite the risk of food challenge test (FCT), the diagnostic laboratory test of FPIES has not been established yet. We experienced a severe FPIES case with boiled egg yolk (b-EY) and examined the Lymphocyte proliferation response (LPR) with EY extract. Case Description A two-year-old boy performed an FCT with b-EY. He had mild atopic dermatitis and two severe vomiting episodes after b-EY ingestions at home, and his FCT with b-EY was positive one year before. He had 2 g of b-EY under medical observation. Two hours after ingestion, he started repetitive vomiting, followed by fever and diarrhea. Intestinal symptoms continued for 2 days.His WBC and neutrophil count elevated dramatically 5 hours after ingestion and CRP became positive the next day. His stool showed occult blood and eosinophils but no other signs of infectious disease were observed. IL-17A, MIP-3a, G-CSF, GM-CSF, IL-10, IL-2, IL-8, TNF-a, IFN-g, MCP, MIP-1a, -1b, TARC, TRAIL, and MIG but not IL-4, or IL-13 elevated in his serum after ingestion.His LPR with EY extract showed a remarkable response (stimulation index: 6.6 vs 1.2 in control) and GM-CSF, IL-10, IL-2, TNF-a, IFN-g, and IL-5 elevated in the culture supernatant compared to control. Discussion In our case, the serum cytokine profile was similar to the previous report (Lozano-Ojalvo 2023), LPR showed positive, and the inflammatory cytokines were induced in its supernatant. The LPR may be useful in diagnosing severe FPIES.

The 2015 Gorkha earthquake in Nepal triggered a large avalanche in Langtang, covering the village with avalanche debris and causing severe damage. The analysis of this disaster was conducted using an avalanche dynamics simulation, which estimated the potential hazards to the village. Avalanche dynamics simulations were performed using the TITAN2D model to obtain the appropriate input parameters for largescale avalanche flows. Using these input parameters, we calculated the avalanche flows for various initial volumes to obtain a lower bound for the potential hazard to Langtang Village. Based on the lower bound, it was estimated that both earthquake-induced and ice avalanches could threaten villages in the future. We also attempted to create a hazard map to estimate the areas around Langtang village where avalanches may have occurred. Using the Polynomial Chaos Quadrature, we were able to account for the uncertainties in the input parameters at a low computational cost.

In the Niseko area in Hokkaido, Japan, a unique set of rules -the "Niseko Rules"- control the opening and closing of gates to allow off-course skiing according to the avalanche danger level. In recent years, the need for scientific evidence that can correctly explain the Niseko Rules and the establishment of human resource training and organizational systems to ensure their continued operation has become apparent. Therefore, in collaboration with the local government and ski resorts, this study developed a system to generate snow redistribution information, which is important for determining avalanche risks in the Niseko area. The constructed system provides wind observation data at multiple points in ski resorts, wind spatial distribution simulations based on observational data, snow redistribution simulations based on wind spatial distribution simulations, and wind spatial distribution and snow redistribution forecast information based on meteorological forecasted data. Research has continued to improve the accuracy of these simulations. Agile research and development are also underway to improve the usability of the system in ski resorts and affected municipalities.

固液混相流である土石流・泥流を一流体連続体モデルとして扱った数値シミュレーションモデルの物性値を雪崩の値に置き換え，固気混相流である雪崩の発達・減衰過程を考慮した数値シミュレーションモデルを開発した．また，開発した雪崩の数値シミュレーションモデルを2020年2月に北海道のピンネシリ岳及び2019年3月に栃木県の茶臼岳で発生した雪崩に適用し，雪崩の流動現象の再現を試みた．その結果，ピンネシリ岳の雪崩の堆積域は，堆積場所，堆積域の大きさなど，現地の堆積域と近い値となった．また，雪崩の堆積量は発生域での雪の崩壊量の約5倍となっており，雪崩の発達過程を考慮した解析が可能となった．数値シミュレーションによると，ピンネシリ岳の雪崩は，斜面を平均約15m/sで流下した．流下するにつれて流動深は深くなり，一部の領域では8 mを超えている．雪崩発生から停止までの時間は約200 秒であった．茶臼岳で発生した雪崩は流動の様子がwebカメラで撮影されていた．そのため，撮影された写真を用いて雪崩の流下速度の再現性の検討を行った．その結果，数値シミュレーションにおいても観測された雪崩と同様に，発生から14秒で斜面下部の緩勾配域まで雪崩が到達しており，雪崩の流下速度の再現性も確認された．

Surface shear stresses produced by wind and particle collision play a key role in aerodynamic entrainment and splash processes. The fluid shear stress at the surface during aeolian transport has been researched for decades; however, the equilibrium property reported in the literature, numerical simulations, and experiments is inconsistent. To discuss this discrepancy, this study investigates fluid and particle shear stresses at the surface during the aeolian transport of snow particles using a two-dimensional random-flight model of drifting snow. The simulations are performed for various friction velocities on a loose snow bed. By varying the wind conditions in stages, the transport hysteresis is confirmed, and the impact threshold is estimated from the particle transport rate ( $$0.206\,\hbox {m\,s}^{-1}$$ ). The friction velocity at the surface during transport decreases marginally with an increase in wind speed caused by the impact threshold, revealing that our results do not contradict Owen’s second hypothesis. The total shear stress, which is calculated by summing the fluid and particle shear stresses, is vertically uniform in the equilibrium state; thus, the increase in the particle shear stress decreases the fluid shear stress at the surface. The equilibrium property of the fluid shear stress near the surface changes significantly with height (from a decreasing trend to an increasing trend) because the particle shear stress decreases rapidly in the height range of 1–10 mm. Our findings suggest that it is difficult to accurately measure the fluid shear stress in the surface vicinity using anemometers, and a new methodology is needed.

We introduce a new procedure to evaluate the snowdrift distribution over complex topography and improve the accuracy of snow avalanche warning systems. We select the Niseko region, Japan, as the target area, and first obtain the wind distribution map at a 50-m grid spacing for 16 wind directions. We then employ these maps to calculate the amount of snow erosion and deposition. We present a case study to demonstrate that the model output agrees fairly well with measurements of local wind speed and observed snowdrift distribution. While improvements can be made to improve the accuracy of the model results, including more comprehensive calculation procedures and quantitative comparisons of snowdrift formation and evolution, it appears that the presented snowdrift analysis is an effective tool that can be incorporated into a snow avalanche warning system that employs a simple snow-cover model.

吹雪は,風により雪が空気中を輸送される現象であり,乱流による気流の変動に伴い,その性状が,時間・空間的に大きく変動する.そのため,吹雪の特徴量に関しては,定常的な性状だけでなく,乱流変動に伴うばらつきなど非定常的な性状の把握も重要である.本研究では,浮遊層の乱流変動とそれに伴う飛雪流量の変動や稀に発生する大きな飛雪流量の現象を把握することを目的として,北海道弟子屈町の雪原で吹雪のタワー観測を実施し,1.0,1.5,3.0,7.0 mの4高度の風速及び飛雪流量の時系列データを取得した.そして,吹雪が発生していた区間を10分間毎に抽出し,それぞれにおける飛雪流量の時空間変動に関する分析を行った.結果として,吹雪時,10分間における飛雪流量の99及び99.5パーセンタイル値は,各々,10分間平均値の10倍及び15倍程度の値となっていた.さらに,飛雪流量の3秒間移動平均値の最大値と99.5パーセンタイル値は概ね一致しており,吹雪が連続的に発生する条件下では,歩行者や運転者の目線高さにおける飛雪流量は瞬間的に平均値の15倍程度となることが明らかになった.

*These authors contributed equally to this work Introduction: Although the ability of androgens to promote prostate cancer development has been known for decades, the molecular mechanisms of androgen receptor (AR) signaling in the tumorigenesis remain unclear. Enhancer RNAs (eRNAs) transcribed from strong enhancers, or super-enhancers (SEs), have recently emerged as a novel class of regulatory non-coding RNAs (ncRNAs) that facilitate transcription, including that of androgen target genes, through chromatin looping to position enhancers proximate to the promoters. The aim of this study was to assess androgen-dependent transcription in prostate tumors of eRNAs (designated as KLK3eRNAs) from the SE of the KLK3 gene encoding the prostate-specific antigen (PSA) protein, a clinical marker of prostate carcinogenesis. Materials and Methods: The androgen-induced KLK3eRNAs were identified in the LNCaP human prostate cancer cell line. The expressions of these KLK3eRNAs together with KLK3 and AR mRNA transcripts were assessed by qRT-PCR in prostate tumor samples from five prostate cancer patients. Results: Androgen-induced KLK3eRNAs have been identified in the LNCaP cells, and their expression was further analyzed in tumors of prostate cancer patients. Transcripts of the tested KLK3eRNAs have been detected in all clinical samples, but their expression patterns differed between individual tumor specimens. We found a statistically significant correlation between the levels of the KLK3 and AR mRNAs with those of the previously reported KLK3eRNAs, while such correlation was not observed for novel KLK3eRNAs described in our recent report. Conclusion: Presented data suggest that prostate tumor development may associate with epigenetic reorganization in the KLK3 genomic regulatory elements reflected by changes of the KLK3eRNA expression. Our findings support a potential of eRNAs profiling to be used as diagnostic marker.

We evaluated the long-term efficacy and safety of an OIT protocol, step-up method for severe cow's milk (CM) allergy patients.

The influence of drifting and blowing snow on surface mass and energy exchange is difficult to quantify due to limitations in both measurements and models, but is still potentially very important over large areas with seasonal or perennial snow cover. We present a unique set of measurements that make possible the calculation of turbulent moisture, heat, and momentum fluxes during conditions of drifting and blowing snow. From the data, Monin–Obukhov estimation of bulk fluxes is compared to eddy-covariance-derived fluxes. In addition, large-eddy simulations with sublimating particles are used to more completely understand the vertical profiles of the fluxes. For a storm period at the Syowa S17 station in East Antarctica, the bulk parametrization severely underestimates near-surface heat and moisture fluxes. The large-eddy simulations agree with the eddy-covariance fluxes when the measurements are minimally disturbed by the snow particles. We conclude that overall exchange over snow surfaces is much more intense than current models suggest, which has implications for the total mass balance of the Antarctic ice sheet and the cryosphere.

雪面上を吹き渡る風によって雪粒子が舞い上げられ移動する吹雪は,極地や山岳地,氷河氷床上の水・エネルギー循環や質量収支から道路や鉄道,建築分野における雪害に至るまで,様々な分野に深く関連する雪氷現象である.各々の分野において吹雪の現象そのものや影響を評価する目的で,長年にわたり,様々な計測や観測,調査が試みられてきた.本稿では,吹雪量や空間密度などの基礎的な計測から,防災・建設分野等の応用分野における調査方法等,吹雪に関する計測,調査方法を解説する.

As an introduction for non-specialists to the Special Issue on snow avalanche dynamics, this paper first outlines how understanding the dynamics of snow avalanches can contribute to reducing risk for settlements and infrastructure. The main knowledge gaps in this field of research concern (i) the properties of the flow regimes and the transitions between them, and (ii) the dynamics of mass change due to erosion and deposition. These two aspects are intertwined and determine not only the reach of an avalanche, but also its velocity, course and impact pressure. Experimental studies described in this Special Issue comprise a wide range of scales from small rotating drums to real snow avalanches. In addition, several papers describe post-event field surveys of specific avalanches and analyze them using different methods and techniques, demonstrating how valuable qualitative insight can be gained in this way. The theoretical developments range from exploratory studies of fluid–particle interactions to a comprehensive review of half a century of avalanche flow modeling in Russia.

This paper describes a simple snow-cover model (SSCM) that was developed primarily to evaluate the hazard to traffic posed by snow avalanches. The SSCM requires only air temperature and precipitation or snow depth as input data, and we simplified the physical processes that affect the snowpack in the model. Snow pit observations and the calculation for avalanche cases were carried out to verify the SSCM output. The SSCM was able to reproduce the change in the snowpack properties fairly well. Further, the snow stability index, which shows the ratio of shear strength to shear stress in the snow, indicated that the SSCM can he used to provide a reliable estimate of avalanche hazard.

Two consecutive cruises in the Weddell Sea, Antarctica, in winter 2013 provided the first direct observations of sea salt aerosol (SSA) production from blowing snow above sea ice, thereby validating a model hypothesis to account for winter time SSA maxima in the Antarctic. Blowing or drifting snow often leads to increases in SSA during and after storms. For the first time it is shown that snow on sea ice is depleted in sulfate relative to sodium with respect to seawater. Similar depletion in bulk aerosol sized ∼0.3–6 µm above sea ice provided the evidence that most sea salt originated from snow on sea ice and not the open ocean or leads, e.g. >90 % during the 8 June to 12 August 2013 period. A temporally very close association of snow and aerosol particle dynamics together with the long distance to the nearest open ocean further supports SSA originating from a local source. A mass budget estimate shows that snow on sea ice contains even at low salinity (<0.1 psu) more than enough sea salt to account for observed increases in atmospheric SSA during storms if released by sublimation. Furthermore, snow on sea ice and blowing snow showed no or small depletion of bromide relative to sodium with respect to seawater, whereas aerosol was enriched at 2 m and depleted at 29 m, suggesting that significant bromine loss takes place in the aerosol phase further aloft and that SSA from blowing snow is a source of atmospheric reactive bromine, an important ozone sink, even during winter darkness. The relative increase in aerosol concentrations with wind speed was much larger above sea ice than above the open ocean, highlighting the importance of a sea ice source in winter and early spring for the aerosol burden above sea ice. Comparison of absolute increases in aerosol concentrations during storms suggests that to a first order corresponding aerosol fluxes above sea ice can rival those above the open ocean depending on particle size. Evaluation of the current model for SSA production from blowing snow showed that the parameterizations used can generally be applied to snow on sea ice. Snow salinity, a sensitive model parameter, depends to a first order on snowpack depth and therefore was higher above first-year sea ice (FYI) than above multi-year sea ice (MYI). Shifts in the ratio of FYI and MYI over time are therefore expected to change the seasonal SSA source flux and contribute to the variability of SSA in ice cores, which represents both an opportunity and a challenge for the quantitative interpretation of sea salt in ice cores as a proxy for sea ice.