Monitoring Icequakes in East Antarctica with the Raspberry Shake

2021 ◽  
Author(s):  
Kate Winter ◽  
Denis Lombardi ◽  
Alejandro Diaz-Moreno ◽  
Rupert Bainbridge
Keyword(s):  
Surface Temperature ◽  
Thermal State ◽  
Low Cost ◽  
Extreme Environments ◽  
Weather Conditions ◽  
East Antarctica ◽  
Katabatic Wind ◽  
Research Station ◽  
Seismic Signals ◽  
High Background

Abstract We evaluate the performance of the low-cost seismic sensor Raspberry Shake (RS) to identify and monitor icequakes (which occur when glacial ice experiences brittle deformation) in extreme environments. In January 2020, three RS3D sensors were installed on a katabatic wind-scoured blue ice area (BIA) close to the Princess Elisabeth Antarctica research station in Dronning Maud Land, East Antarctica. The sensors were configured for Antarctic deployment and placed in insulated enclosures to protect them from harsh weather systems. The RS network (installed in a triangular array) performed well in the cold and with rapid air temperature change, as diurnal temperatures fluctuated from a high of 0.0°C to a minimum temperature of −15.0°C. Although battery connectivity issues in one unit limit full triangulation of seismic signals, and high background noise may mask some seismic signals, data from the RS2 unit reveals that 2936 icequakes were detected over a 10-day period. The temporal occurrence of these icequakes, combined with satellite-derived surface temperature measurements and automatic weather station data, suggest that diurnal fluctuations in solar radiation control ice surface temperature changes, driving thermal contraction of the ice. Seismic investigations like these can therefore provide information on the thermal state and ice fracture mechanics of ablation zones such as BIAs. Our work highlights the potential application of the RS (after minimal modification) in glaciated environments where equipment often needs to be portable, temporary and lightweight, and able to perform in extreme weather conditions.

scholarly journals Turning Base Transceiver Stations into Scalable and Controllable DC Microgrids Based on a Smart Sensing Strategy

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1202
Author(s):  
Miguel Tradacete ◽  
Carlos Santos ◽  
José A. Jiménez ◽  
Fco Javier Rodríguez ◽  
Pedro Martín ◽  
...  
Keyword(s):  
Electricity Market ◽  
Low Cost ◽  
Storage System ◽  
Environmental Parameters ◽  
Weather Conditions ◽  
Energy Storage System ◽  
Electricity Grid ◽  
Dc Microgrids ◽  
Smart Sensing ◽  
Battery Energy

This paper describes a practical approach to the transformation of Base Transceiver Stations (BTSs) into scalable and controllable DC Microgrids in which an energy management system (EMS) is developed to maximize the economic benefit. The EMS strategy focuses on efficiently managing a Battery Energy Storage System (BESS) along with photovoltaic (PV) energy generation, and non-critical load-shedding. The EMS collects data such as real-time energy consumption and generation, and environmental parameters such as temperature, wind speed and irradiance, using a smart sensing strategy whereby measurements can be recorded and computing can be performed both locally and in the cloud. Within the Spanish electricity market and applying a two-tariff pricing, annual savings per installed battery power of 16.8 euros/kW are achieved. The system has the advantage that it can be applied to both new and existing installations, providing a two-way connection to the electricity grid, PV generation, smart measurement systems and the necessary management software. All these functions are integrated in a flexible and low cost HW/SW architecture. Finally, the whole system is validated through real tests carried out on a pilot plant and under different weather conditions.

scholarly journals Temperature distribution in a permafrost-affected rock ridge from conductivity and induced polarization tomography

2020 ◽  
Author(s):  
P-A Duvillard ◽  
F Magnin ◽  
A Revil ◽  
A Legay ◽  
L Ravanel ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Temperature Distribution ◽  
Thermal State ◽  
Low Cost ◽  
Freezing Temperature ◽  
Induced Polarization ◽  
Rock Surface ◽  
European Alps ◽  
Limited Information ◽  
Polarization Tomography

Summary Knowledge of the thermal state of steep alpine rock faces is crucial to assess potential geohazards associated with the degradation of permafrost. Temperature measurements at the rock surface or in boreholes are however expensive, invasive, and provide spatially-limited information. Electrical conductivity and induced polarization tomography can detect permafrost. We test here a recently developed petrophysical model based on the use of an exponential freezing curve applied to both electrical conductivity and normalized chargeability to infer the distribution of temperature below the freezing temperature. We then apply this approach to obtain the temperature distribution from electrical conductivity and normalized chargeability field data obtained across a profile extending from the SE to NW faces of the lower Cosmiques ridge (Mont Blanc massif, Western European Alps, 3613 m a.s.l., France). The geophysical datasets were acquired both in 2016 and 2019. The results indicate that the only NW face of the rock ridge is frozen. To evaluate our results, we model the bedrock temperature across this rock ridge using CryoGRID2, a 1D MATLAB diffusive transient thermal model and surface temperature time series. The modelled temperature profile confirms the presence of permafrost in a way that is consistent with that obtained from the geophysical data. Our study offers a promising low-cost approach to monitor temperature distribution in Alpine rock walls and ridges in response to climate change.

Corrosion resistant metal-ceramic composite coatings for tribological applications

2021 ◽  
pp. 1-34
Author(s):  
Peter Renner ◽  
Swarn Jha ◽  
Yan Chen ◽  
Tariq Chagouri ◽  
Serge Kazadi ◽  
...  
Keyword(s):  
Ceramic Composite ◽  
Low Cost ◽  
Composite Coatings ◽  
Salt Spray ◽  
Extreme Environments ◽  
Safe Procedure ◽  
Corrosion Resistant ◽  
Wide Range ◽  
Metal Ceramic ◽  
Corrosion Resistant Coatings

Abstract Effective design of corrosion-resistant coatings is critical for the protection of metals and alloys. Many state-of-the-art corrosion-resistant coatings are unable to satisfy the challenges in extreme environments for tribological applications, such as elevated or cryogenic temperatures, high mechanical loads and impacts, severe wear, chemical attack, or a combination of these. The nature of challenging conditions demands that coatings have high corrosion and wear resistance, sustained friction control, and maintain surface integrity. In this research, multi-performance metal-ceramic composite coatings were developed for applications in harsh environments. These coatings were developed with an easy to fabricate, low-cost, and safe procedure. The coating consisted of boron nitride, graphite, silicon carbide, and transition metals such as chromium or nickel using epoxy as vehicle and bonding agent. Salt spray corrosion tests showed that 1010 carbon steel (1/4 hard temper) substrates lost 20-100× more mass than the coatings. The potentiodynamic polarization study showed better performance of the coatings by seven orders of magnitude in terms of corrosion relative to the substrate. Additionally, the corrosion rates of the coatings with Ni as an additive were five orders of magnitude lower than reported. The coefficient of friction of coatings was as low as 0.1, five to six times lower than that of epoxy and lower than a wide range of epoxy resin-based coatings found in literature. Coatings developed here exhibited potential in applications in challenging environments for tribological applications.

scholarly journals Brief communication: Rare ambient saturation during drifting snow occurrences at a coastal location of East Antarctica

2019 ◽  
Vol 13 (12) ◽  
pp. 3405-3412 ◽  
Author(s):  
Charles Amory ◽  
Christoph Kittel
Keyword(s):  
Relative Humidity ◽  
Meteorological Data ◽  
Ice Sheet ◽  
Ambient Air ◽  
East Antarctica ◽  
Strong Increase ◽  
Katabatic Wind ◽  
Strong Wind ◽  
Near Surface ◽  
Drifting Snow

Abstract. Sublimation of snow particles during transport has been recognized as an important ablation process on the Antarctic ice sheet. The resulting increase in moisture content and cooling of the ambient air are thermodynamic negative feedbacks that both contribute to increase the relative humidity of the air, inhibiting further sublimation when saturation is reached. This self-limiting effect and the associated development of saturated near-surface air layers in drifting snow conditions have mainly been described through modelling studies and a few field observations. A set of meteorological data, including drifting snow mass fluxes and vertical profiles of relative humidity, collected at site D17 in coastal Adélie Land (East Antarctica) during 2013 is used to study the relationship between saturation of the near-surface atmosphere and the occurrence of drifting snow in a katabatic wind region that is among the most prone to snow transport by wind. Atmospheric moistening by the sublimation of the windborne snow particles generally results in a strong increase in relative humidity with the magnitude of drifting snow and a decrease in its vertical gradient, suggesting that windborne-snow sublimation can be an important contributor to the local near-surface moisture budget. Despite a high incidence of drifting snow at the measurement location (60.1 % of the time), saturation, when attained, is however most often limited to a thin air layer below 1 m above ground. The development of a near-surface saturated air layer up to the highest measurement level of 5.5 m is observed in only 8.2 % of the drifting snow occurrences or 6.3 % of the time and mainly occurs in strong wind speed and drift conditions. This relatively rare occurrence of ambient saturation is explained by the likely existence of moisture-removal mechanisms inherent to the katabatic and turbulent nature of the boundary-layer flow that weaken the negative feedback of windborne-snow sublimation. Such mechanisms, potentially quite active in katabatic-generated windborne-snow layers all over Antarctica, may be very important in understanding the surface mass and atmospheric moisture budgets of the ice sheet by enhancing windborne-snow sublimation.

scholarly journals A Numerical Study of Plane Ice-Sheet Flow

1986 ◽  
Vol 32 (111) ◽  
pp. 139-160 ◽  
Author(s):  
K. Hutter ◽  
S. Yakowitz ◽  
F. Szidarovszky
Keyword(s):  
Surface Temperature ◽  
Thermal State ◽  
Numerical Study ◽  
Ice Sheets ◽  
Ice Sheet ◽  
Tangential Velocity ◽  
Rigid Base ◽  
Geothermal Heat ◽  
Functional Relations ◽  
External Forcings

AbstractThe plane steady flow of a grounded ice sheet is numerically analysed using the approximate model of Morland or Hutter. In this, the ice behaves as a non-linear viscous fluid with a strongly temperature-dependent rate factor, and ice sheets are assumed to be long and shallow. The climate is assumed to be prescribed via the accumulation/ablation distribution and the surface temperature, both of which are functions of position and unknown height. The rigid base exerts external forcings via the normal heat flow, the geothermal heat, and a given basal sliding condition connecting the tangential velocity, tangential traction, and normal traction. The functional relations are those of Morland (1984) or motivated by his work. We use equations in his notation.The governing equations and boundary conditions in dimensionless form are briefly stated and dimensionless variables are related to their physical counterparts. The thermo-mechanical parabolic boundary-value problem, found to depend on physical scales, constitutive properties, and external forcing functions, has been numerically solved. For reasons of stability, the numerical integration must proceed from the ice divide towards the margin, which requires a special analysis of the ice divide. We present this analysis and then describe the versatility and limitations of the constructed computer code.Results of extensive computations are shown. In particular, we prove that the Morland–Hutter model for ice sheets is only applicable when sliding is sufficiently large (satisfying inequality (30)). In the range of the validity of this inequality, it is then demonstrated that of all physical scaling parameters only a single π-product influences the geometry and the flow within the ice sheet. We analyse the role played by advection, diffusion, and dissipation in the temperature distribution, and discuss the significance of the rheological non-linearities. Variations of the external forcings, such as accumulation/ablation conditions, free surface temperature, and geothermal heat, demonstrate the sensitivity of the ice-sheet geometry to accumulation conditions and the robustness of the flow to variations in the thermal state. We end with a summary of results and a critical review of the model.

Modelling pavement temperature for winter maintenance operations

2004 ◽  
Vol 31 (2) ◽  
pp. 369-378 ◽  
Author(s):  
Aly Sherif ◽  
Yasser Hassan
Keyword(s):  
Surface Temperature ◽  
Air Temperature ◽  
Negative Impact ◽  
Weather Conditions ◽  
Statistical Modelling ◽  
Dew Point ◽  
Road Maintenance ◽  
Winter Maintenance ◽  
Pavement Surface ◽  
Pavement Temperature

Road and highway maintenance is vital for the safety of citizens and for enabling emergency and security services to perform their essential functions. Accumulation of snow and (or) ice on the pavement surface during the wintertime substantially increases the risk of road crashes and can have negative impact on the economy of the region. Recently, road maintenance engineers have used pavement surface temperature as a guide to the application of deicers. Stations for road weather information systems (RWIS) have been installed across Europe and North America to collect data that can be used to predict weather conditions such as air temperature. Modelling pavement surface temperature as a function of such weather conditions (air temperature, dew point, relative humidity, and wind speed) can provide an additional component that is essential for winter maintenance operations. This paper uses data collected by RWIS stations at the City of Ottawa to device a procedure that maximizes the use of a data batch containing complete, partially complete, and unusable data and to study the relationship between the pavement surface temperature and weather variables. Statistical models were developed, where stepwise regression was first applied to eliminate those variables whose estimated coefficients are not statistically significant. The remaining variables were further examined according to their contribution to the criterion of best fit and their physical relationships to each other to eliminate multicollinearities. The models were further corrected for the autocorrelation in their error structures. The final version of the developed models may then be used as a part of the decision-making process for winter maintenance operations.Key words: winter maintenance, pavement temperature, statistical modelling, RWIS.

Comparison of two gap-filling techniques for nitrous oxide fluxes from agricultural soil

2019 ◽  
Vol 99 (1) ◽  
pp. 12-24 ◽  
Author(s):  
Rezvan Taki ◽  
Claudia Wagner-Riddle ◽  
Gary Parkin ◽  
Rob Gordon ◽  
Andrew VanderZaag
Keyword(s):  
Missing Values ◽  
Interpolation Method ◽  
Weather Conditions ◽  
Linear Interpolation ◽  
Bias Error ◽  
Research Station ◽  
Ann Model ◽  
Gap Filling ◽  
Adverse Weather ◽  
The Impact

Micrometeorological methods are ideally suited for continuous measurements of N2O fluxes, but gaps in the time series occur due to low-turbulence conditions, power failures, and adverse weather conditions. Two gap-filling methods including linear interpolation and artificial neural networks (ANN) were utilized to reconstruct missing N2O flux data from a corn–soybean–wheat rotation and evaluate the impact on annual N2O emissions from 2001 to 2006 at the Elora Research Station, ON, Canada. The single-year ANN method is recommended because this method captured flux variability better than the linear interpolation method (average R2 of 0.41 vs. 0.34). Annual N2O emission and annual bias resulting from linear and single-year ANN were compatible with each other when there were few and short gaps (i.e., percentage of missing values <30%). However, with longer gaps (>20 d), the bias error in annual fluxes varied between 0.082 and 0.344 kg N2O-N ha−1 for linear and 0.069 and 0.109 kg N2O-N ha−1 for single-year ANN. Hence, the single-year ANN with lower annual bias and stable approach over various years is recommended, if the appropriate driving inputs (i.e., soil temperature, soil water content, precipitation, N mineral content, and snow depth) needed for the ANN model are available.

scholarly journals Observed decreases in on-road CO<sub>2</sub> concentrations in Beijing during COVID-19 restrictions

2021 ◽  
Vol 21 (6) ◽  
pp. 4599-4614
Author(s):  
Di Liu ◽  
Wanqi Sun ◽  
Ning Zeng ◽  
Pengfei Han ◽  
Bo Yao ◽  
...  
Keyword(s):  
Urban Areas ◽  
Low Cost ◽  
Working Hours ◽  
Weather Conditions ◽  
Co2 Concentration ◽  
Mobile Platforms ◽  
Local Standard ◽  
Transportation Emissions ◽  
Enhancement Method ◽  
The Difference

Abstract. To prevent the spread of the COVID-19 epidemic, restrictions such as “lockdowns” were conducted globally, which led to a significant reduction in fossil fuel emissions, especially in urban areas. However, CO2 concentrations in urban areas are affected by many factors, such as weather, biological sinks and background CO2 fluctuations. Thus, it is difficult to directly observe the CO2 reductions from sparse ground observations. Here, we focus on urban ground transportation emissions, which were dramatically affected by the restrictions, to determine the reduction signals. We conducted six series of on-road CO2 observations in Beijing using mobile platforms before (BC), during (DC) and after (AC) the implementation of COVID-19 restrictions. To reduce the impacts of weather conditions and background fluctuations, we analyze vehicle trips with the most similar weather conditions possible and calculated the enhancement metric, which is the difference between the on-road CO2 concentration and the “urban background” CO2 concentration measured at the tower of the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences. The results showed that the DC CO2 enhancement was decreased by 41 (±1.3) parts per million (ppm) and 26 (±6.2) ppm compared to those for the BC and AC trips, respectively. Detailed analysis showed that, during COVID-19 restrictions, there was no difference between weekdays and weekends during working hours (09:00–17:00 local standard time; LST). The enhancements during rush hours (07:00–09:00 and 17:00–20:00 LST) were almost twice those during working hours, indicating that emissions during rush hours were much higher. For DC and BC, the enhancement reductions during rush hours were much larger than those during working hours. Our findings showed a clear CO2 concentration decrease during COVID-19 restrictions, which is consistent with the CO2 emissions reductions due to the pandemic. The enhancement method used in this study is an effective method to reduce the impacts of weather and background fluctuations. Low-cost sensors, which are inexpensive and convenient, could play an important role in further on-road and other urban observations.

scholarly journals Influence of the growth regulator “Regoplant” and microfertilizer “Ultramag Kombi” on photosynthetic activity of potatoes in the forest-steppe zone Republic of North Ossetia-Alania

2021 ◽  
Vol 210 (07) ◽  
pp. 55-65
Author(s):  
Larisa Ikoeva ◽  
Oksana Haeva
Keyword(s):  
Growth Regulator ◽  
Field Experiments ◽  
Photosynthetic Activity ◽  
Low Cost ◽  
Weather Conditions ◽  
Steppe Zone ◽  
Practical Significance ◽  
Forest Steppe ◽  
Photosynthetic Productivity ◽  
North Ossetia

Abstract. The purpose of the work is to study the influence of the growth regulator “Regoplant” and microfertilizer “Ultramag Kombi” on the photosynthetic productivity of the potatoes of the Barna variety based on the results of field experiments in the forest-steppe zone Republic of North Ossetia-Alania. Methods. Studies on the tasks were carried out in 2018–2020. at the experimental site of the NCRIMFA branch of the VSC of RAS in the conditions of the forest-steppe zone Republic of North Ossetia-Alania according to generally accepted methods. The soil of the experimental plot is medium-power heavy loamy leached chernozem, lined with pebbles. Results. It is established, that biological products under identical soil and weather conditions assisted different progress of plants and approach of phases of vegetation. For all variants of the experiment, the number of stems increased by 0,3–0,7 pcs., the height of the stems of potato plants – by 3,8–4,9 cm in comparison with the control. An intense increase in the mass of tops occurred when using a tank mixture (growth regulator “Regoplant” (25 ml/ha) + microfertilizer “Ultramag Combi” (0,75 l/ha)) – by 74 g/bush, or 15.5 % compared with the control variant. During the growing season, the sum of the photosynthetic potential (FP) was 1,070 thousand m2 •days/ha in the control, and on average 1198–1406 thousand m2•days/ha in the experimental variants. The greatest accumulation of dry matter was noted when using a tank mixture – 917 g/m2. The maximum pure photosynthetic productivity was observed in experimental variant IV – 6,52 g/m2•day compared to the control option. Scientific novelty. For the first time in the forest-steppe zone Republic of North Ossetia-Alania the effect of the growth regulator “Regoplant” and microfertilizer “Ultramag Kombi” on photosynthetic activity of potatoes was studied. Practical significance. The studies carried out make it possible to recommend in potato production the use of a tank mixture of an effective growth regulator “Regoplant” at a dose of 25 ml/ha and microfertilizer “Ultramag Combi” at a dose of 0,75 l/ha, as an ecologically safe and low-cost agricultural method when processing vegetative plants, providing an increase in yield and quality of tubers.

scholarly journals GEOMATIC TECHNIQUES FOR THE OPTIMIZATION OF SKI RESOURCES

2020 ◽  
Vol XLIII-B2-2020 ◽  
pp. 1009-1016
Author(s):  
I. Aicardi ◽  
S. Angeli ◽  
N. Grasso ◽  
A. M. Lingua ◽  
P. Maschio
Keyword(s):  
Heat Waves ◽  
Low Cost ◽  
Winter Season ◽  
Heavy Rain ◽  
Weather Conditions ◽  
Fundamental Aspect ◽  
Carbon Neutrality ◽  
Aerial Vehicle ◽  
Gnss Receivers ◽  
Processing Techniques

Abstract. Climate change is already affecting the entire world, with extreme weather conditions such as drought, heat waves, heavy rain, floods and landslides becoming more frequent, including Europe. In according to Paris agreement and relative European announcement of Carbon neutrality (by 2050), the saving of water and energy supplies is a fundamental aspect in the management of resources in production, sports, hospitality facilities and so on. Some methodologies for the optimization of the consumption of natural resources are required. This article describes an activity aimed at measuring, monitoring and analysing the thickness of the snowpack on the ski slopes during the winter season to permit a sustainable approach of snowmaking in alpine ski areas . The authors propose a methodology based on the integration of multitemporal surface (ground/snow) survey by Autonomous Aerial Vehicle (AAV) and low cost GNSS receivers mounted on snow groomers for a RTK (Real Time Kinematic) solution. To obtain a complete snow surface digital models with poor detailed images on ski slopes, some pre-processing techniques have been analysed to locally improve contrast and details with a local high pass filtering. The methodology has been employed in two study areas (Limone Piemonte, Prato Nevoso) located in the province of Cuneo, in the southern alpine area of Piedmont.

Sign in / Sign up

Export Citation Format

Share Document