scholarly journals The AEMET-<i>γ</i>SREPS over the Antarctic Peninsula and the impact of kilometric-resolution EPS on logistic activities on the continent

2020 ◽  
Vol 17 ◽  
pp. 209-217
Author(s):  
Sergi Gonzalez ◽  
Alfons Callado ◽  
Mauricia Martínez ◽  
Benito Elvira
Keyword(s):  
Boundary Conditions ◽  
Antarctic Peninsula ◽  
Positive Impact ◽  
Austral Summer ◽  
Added Value ◽  
Ensemble Prediction ◽  
Prediction Systems ◽  
Nwp Model ◽  
The Antarctic ◽  
The Impact

Abstract. Kilometric-resolution Ensemble Prediction Systems (EPSs) will be the new state-of-the-art forecasting tools for short-range prediction in the following decade. Their value will be even greater in Antarctica due to the increasingly demanding weather forecasts for logistic services. During the 2018–2019 austral summer (1 December–31 March), coinciding with the Southern Hemisphere Special Observation Period of the Year of Polar Prediction (YOPP), the 2.5 km AEMET-γSREPS was operationally integrated over the Antarctic Peninsula. In particular, the Antarctic version of γSREPS comes up with crossing four non-hydrostatic convection-permitting NWP models at 2.5 km with three global NWP driving models as boundary conditions. The γSREPS forecasting system has been validated in comparison with ECMWF EPS. It is concluded that γSREPS has an added value to ECMWF EPS due to both its higher resolution and its multi-boundary conditions and multi-NWP model approach. γSREPS performance has a positive impact on logistic activities at research stations and its design may contribute to polar prediction research.

scholarly journals An Assessment of ERA5 Reanalysis for Antarctic Near-Surface Air Temperature

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 217
Author(s):  
Jiangping Zhu ◽  
Aihong Xie ◽  
Xiang Qin ◽  
Yetang Wang ◽  
Bing Xu ◽  
...  
Keyword(s):  
Linear Relationship ◽  
Antarctic Peninsula ◽  
Austral Summer ◽  
Correlation Coefficients ◽  
East Antarctica ◽  
West Antarctica ◽  
Austral Spring ◽  
Reanalysis Dataset ◽  
Near Surface ◽  
The Antarctic

The European Center for Medium-Range Weather Forecasts (ECMWF) released its latest reanalysis dataset named ERA5 in 2017. To assess the performance of ERA5 in Antarctica, we compare the near-surface temperature data from ERA5 and ERA-Interim with the measured data from 41 weather stations. ERA5 has a strong linear relationship with monthly observations, and the statistical significant correlation coefficients (p < 0.05) are higher than 0.95 at all stations selected. The performance of ERA5 shows regional differences, and the correlations are high in West Antarctica and low in East Antarctica. Compared with ERA5, ERA-Interim has a slightly higher linear relationship with observations in the Antarctic Peninsula. ERA5 agrees well with the temperature observations in austral spring, with significant correlation coefficients higher than 0.90 and bias lower than 0.70 °C. The temperature trend from ERA5 is consistent with that from observations, in which a cooling trend dominates East Antarctica and West Antarctica, while a warming trend exists in the Antarctic Peninsula except during austral summer. Generally, ERA5 can effectively represent the temperature changes in Antarctica and its three subregions. Although ERA5 has bias, ERA5 can play an important role as a powerful tool to explore the climate change in Antarctica with sparse in situ observations.

scholarly journals Impacts of Assimilating ATMS Radiances on Heavy Rainfall Forecast in RMAPS-ST

2020 ◽  
Vol 12 (7) ◽  
pp. 1147
Author(s):  
Yanhui Xie ◽  
Min Chen ◽  
Jiancheng Shi ◽  
Shuiyong Fan ◽  
Jing He ◽  
...  
Keyword(s):  
Heavy Rainfall ◽  
Initial Conditions ◽  
Positive Impact ◽  
Weather Prediction ◽  
Advanced Technology ◽  
Added Value ◽  
Rainfall Forecast ◽  
Hourly Rainfall ◽  
Radiance Data ◽  
The Impact

The Advanced Technology Microwave Sounder (ATMS) mounted on the Suomi National Polar-Orbiting Partnership (NPP) satellite can provide both temperature and humidity information for a weather prediction model. Based on the rapid-refresh multi-scale analysis and prediction system—short-term (RMAPS-ST), we investigated the impact of ATMS radiance data assimilation on strong rainfall forecasts. Two groups of experiments were conducted to forecast heavy precipitation over North China between 18 July and 20 July 2016. The initial conditions and forecast results from the two groups of experiments have been compared and evaluated against observations. In comparison with the first group of experiments that only assimilated conventional observations, some added value can be obtained for the initial conditions of temperature, humidity, and wind fields after assimilating ATMS radiance observations in the system. For the forecast results with the assimilation of ATMS radiances, the score skills of quantitative forecast rainfall have been improved when verified against the observed rainfall. The Heidke skill score (HSS) skills of 6-h accumulated precipitation in the 24-h forecasts were overall increased, more prominently so for the heavy rainfall above 25 mm in the 0–6 h of forecasts. Assimilating ATMS radiance data reduced the false alarm ratio of quantitative precipitation forecasting in the 0–12 h of the forecast range and thus improved the threat scores for the heavy rainfall storm. Furthermore, the assimilation of ATMS radiances improved the spatial distribution of hourly rainfall forecast with observations compared with that of the first group of experiments, and the mean absolute error was reduced in the 10-h lead time of forecasts. The inclusion of ATMS radiances provided more information for the vertical structure of features in the temperature and moisture profiles, which had an indirect positive impact on the forecasts of the heavy rainfall in the RMAPS-ST system. However, the deviation in the location of the heavy rainfall center requires future work.

scholarly journals Changes in ice-shelf buttressing following the collapse of Larsen A Ice Shelf, Antarctica, and the resulting impact on tributaries

2016 ◽  
Vol 62 (235) ◽  
pp. 905-911 ◽  
Author(s):  
SAM ROYSTON ◽  
G. HILMAR GUDMUNDSSON
Keyword(s):  
Antarctic Peninsula ◽  
Surface Velocity ◽  
Ice Shelf ◽  
Mass Redistribution ◽  
Grounding Line ◽  
Modelling Studies ◽  
Speed Up ◽  
Stringent Test ◽  
The Antarctic ◽  
The Impact

ABSTRACTThe dominant mass-loss process on the Antarctic Peninsula has been ice-shelf collapse, including the Larsen A Ice Shelf in early 1995. Following this collapse, there was rapid speed up and thinning of its tributary glaciers. We model the impact of this ice-shelf collapse on upstream tributaries, and compare with observations using new datasets of surface velocity and ice thickness. Using a two-horizontal-dimension shallow shelf approximation model, we are able to replicate the observed large increase in surface velocity that occurred within Drygalski Glacier, Antarctic Peninsula. The model results show an instantaneous twofold increase in flux across the grounding line, caused solely from the reduction in backstress through ice shelf removal. This demonstrates the importance of ice-shelf buttressing for flow upstream of the grounding line and highlights the need to explicitly include lateral stresses when modelling real-world settings. We hypothesise that further increases in velocity and flux observed since the ice-shelf collapse result from transient mass redistribution effects. Reproducing these effects poses the next, more stringent test of glacier and ice-sheet modelling studies.

scholarly journals Cloud-Resolving Ensemble Simulations of Mediterranean Heavy Precipitating Events: Uncertainty on Initial Conditions and Lateral Boundary Conditions

2011 ◽  
Vol 139 (2) ◽  
pp. 403-423 ◽  
Author(s):  
Benoît Vié ◽  
Olivier Nuissier ◽  
Véronique Ducrocq
Keyword(s):  
Boundary Conditions ◽  
Case Studies ◽  
Short Range ◽  
Initial Conditions ◽  
Ensemble Prediction ◽  
Lateral Boundary ◽  
Synoptic Scale ◽  
Lateral Boundary Conditions ◽  
Convective Scale ◽  
The Impact

Abstract This study assesses the impact of uncertainty on convective-scale initial conditions (ICs) and the uncertainty on lateral boundary conditions (LBCs) in cloud-resolving simulations with the Application of Research to Operations at Mesoscale (AROME) model. Special attention is paid to Mediterranean heavy precipitating events (HPEs). The goal is achieved by comparing high-resolution ensembles generated by different methods. First, an ensemble data assimilation technique has been used for assimilation of perturbed observations to generate different convective-scale ICs. Second, three ensembles used LBCs prescribed by the members of a global short-range ensemble prediction system (EPS). All ensembles obtained were then evaluated over 31- and/or 18-day periods, and on 2 specific case studies of HPEs. The ensembles are underdispersive, but both the probabilistic evaluation of their overall performance and the two case studies confirm that they can provide useful probabilistic information for the HPEs considered. The uncertainty on convective-scale ICs is shown to have an impact at short range (under 12 h), and it is strongly dependent on the synoptic-scale context. Specifically, given a marked circulation near the area of interest, the imposed LBCs rapidly overwhelm the initial differences, greatly reducing the spread of the ensemble. The uncertainty on LBCs shows an impact at longer range, as the spread in the coupling global ensemble increases, but it also depends on the synoptic-scale conditions and their predictability.

Behaviour and dive times of Arnoux's beaked whales, Berardius arnuxii, at narrow leads in fast ice

1996 ◽  
Vol 74 (2) ◽  
pp. 388-393 ◽  
Author(s):  
R. P. Hobson ◽  
A. R. Martin
Keyword(s):  
Sea Ice ◽  
Antarctic Peninsula ◽  
Austral Summer ◽  
Food Resources ◽  
Breath Hold ◽  
Beaked Whale ◽  
Horizontal Movement ◽  
Beaked Whales ◽  
Fast Ice ◽  
The Antarctic

Groups of the little-known Arnoux's beaked whale, Berardius arnuxii, were observed at narrow cracks or leads in sea ice near the Antarctic peninsula during the austral summer of 1992–1993. The whales were grey, had a slightly asymmetric blowhole and blow, and were heavily scarred in adulthood. At least 30 animals were uniquely identified using their scars. Despite often cramped conditions at the breathing holes, the whales were always calm and nonaggressive, reacting to the circumstances with surfacing and submerging behaviour involving little horizontal movement. Seventy dive durations by 17 identified adults were recorded, with a mode of 35–65 min and a maximum of at least 70 min. Eight periods of respiration varied between 1.2 and 6.8 min, with an average of 9.6 blows/min. These breath-hold characteristics confirm B. arnuxii as one of the most accomplished mammalian divers, capable of swimming up to an estimated 7 km between breathing sites in sea ice. Whales moved to and from the observed lead, apparently able to find other breathing sites in what appeared to be unbroken ice. The species seems well adapted to life in ice-covered waters and may be able to exploit food resources inaccessible to other predators in the region.

scholarly journals Introducing E-portfolio Use to Primary School Pupils: Response, Benefits and Challenges

10.28945/2158 ◽  
2015 ◽  
Vol 14 ◽  
pp. 017-038 ◽  
Author(s):  
Dimitra Theodosiadou ◽  
Angelos Konstantinidis
Keyword(s):  
Primary School ◽  
Assessment Tool ◽  
Positive Impact ◽  
Added Value ◽  
Primary School Teachers ◽  
Educational Benefits ◽  
Regular Teacher ◽  
Primary School Pupils ◽  
Teacher Data ◽  
The Impact

Electronic portfolios (e-portfolios) have a positive impact on the learning process in a broad range of educational sectors and on learners of all ages. Yet because most e-portfolio-related studies are about their implementation in higher education, this type of research is less usual in the early childhood context, and there is no available research for Greek schools. This study aims to investigate the impact of e-portfolios on learning in a Greek primary school and to provide a resource regarding the educational benefits of e-portfolio in primary education. To do that, it employs the qualitative naturalistic method to collect data, along with mixed methods which were used to achieve triangulation and strengthen confidence in the outcomes. Participants in the research were fourteen 8-year-old pupils, and one of the researchers was their regular teacher. Data evaluation revealed that the e-portfolio added value in pupils’ learning, acted as a medium to involve parents, promoted pupils’ self-esteem, and was acknowledged as a valuable assessment tool and a challenge for the school community. Based on the experience of the e-portfolio implementation, the authors provide some suggestions that would possibly help researchers and primary school teachers adopt and develop e-portfolio systems in their particular settings.

scholarly journals INTERNATIONAL TRADE IN ICT SERVICES: THE CASE OF UKRAINE

2020 ◽  
Vol 113 (6) ◽  
pp. 107-122
Author(s):  
KRASNIKOVA Nataliya ◽  
DZYAD Olena ◽  
HRECHYN Kyrylo
Keyword(s):  
International Trade ◽  
Positive Impact ◽  
Information And Communications Technology ◽  
Added Value ◽  
It Services ◽  
Export Sector ◽  
Goods And Services ◽  
Support For Innovation ◽  
Geographical Regions ◽  
The Impact

Background. Today, the information and communications technology (ICT) sector is one of the most dynamic sectors of the world economy. Since IT services are the second largest export sector in Ukraine, the study of the impact of international trade in ICT services on economic growth becomes relevant. Analysis of recent research and publications. Numerous papers have shown the positive impact of international trade in ICT goods and services on production volumes, employment and productivity of national economies. In particular, UNCTAD data show that the ICT services sector shows an increase in employment and international trade in all geographical regions and provides most of the added value in the ICT sector. The aim of the article is to study the impact of international trade in ICT services on the development of economies of different levels of development, taking into account national policies of ICT sector, and to develop recommendations for Ukrainian policy of ICT sector, taking into account the experience of analyzed countries. Materials and methods. The information base for the study was data from UNCTAD, OECD, Eurostat, and the State Statistics Service of Ukraine. Methods of statistical, structural, regression, comparative analysis are used. Results. Regression analysis was used to identify the relationship between GDP and the volume of exports and imports of ICT services in the analyzed countries. The results showed that in order to ensure economic development through trade in ICT services, countries need to pursue a stimulating policy, which includes measures in three main areas: support for innovation (R&D funding and startup ecosystems); education and training of ICT specialists; and support for investments in ICT services (through preferential taxation and grant schemes). Conclusion. In order to support the growth of the national IT industry, the Ukrainian government is proposed to legalize existing schemes of cooperation of IT companies with private individuals, to avoid additional regulation of the industry, and to develop schemes to financially support innovation in science and business.

scholarly journals The cost management approaches in trade industry

2019 ◽  
Vol 3 (3) ◽  
pp. 35-43
Author(s):  
Iryna Kvach
Keyword(s):  
Positive Impact ◽  
Cost Management ◽  
Unit Cost ◽  
Economic Value ◽  
Value Added ◽  
Added Value ◽  
Activity Based Costing ◽  
The People ◽  
Management Approaches ◽  
The Impact

Introduction. The current state of financial and economic government institutions negatively affects  Ukrainian budget execution, and the general trend of deterioration in the standard of living of the people, in general leads to low level of functioning of the enterprise and  their competitiveness, especially in such industry as trade. Aims and tasks. In the conditions of an unstable political and economic situation in commodity market and services to overcome disproportions between operating profit  of some commodity groups of trade enterprise and its added value which indicates depreciation of the capital  invested by owners not only doesn't provide compensation of investments, but also leads to losses because of inflationary processes therefore there is a need for the mutual integration of approaches of management of expenses for assessment. Results. The practical value of application of a method of Activity-based costing (ABC) and Economic Value Added (EVA) in management of expenses not only in creation of a system of accounting of expenses, but also and predictions through new approaches for the analysis for identification of unproductive fields of activity in value creation of a product is proved, including positively influences the growth of business activity for trade enterprises. In the field of innovative approaches the balanced system of indexes (BSI) and EVA methods harmoniously are integrated in processes of costs planning, management of them at the level of departments and in general are distributed among operation processes to responsible persons, which has a positive impact on maximizing capital cost of the enterprise. Conclusions. Application of methods of cost management as uniform system provides chance to distribute expenses on commodity groups and to define  goods which create added value gives the chance to settle the impact of minimum change of influence of a factor  on commodity turnover level due to decrease of unit  cost in life cycle of a product through the analysis of a point of profitability for increase in investment attractiveness.

Spatial patterns of tour ship traffic in the Antarctic Peninsula region

2009 ◽  
Vol 22 (2) ◽  
pp. 123-130 ◽  
Author(s):  
H.J. Lynch ◽  
K. Crosbie ◽  
W.F. Fagan ◽  
R. Naveen
Keyword(s):  
Antarctic Peninsula ◽  
Spatially Explicit ◽  
Theory Analysis ◽  
Ship Traffic ◽  
Marine Traffic ◽  
Landing Sites ◽  
Pros And Cons ◽  
Tourism Activity ◽  
The Antarctic ◽  
The Impact

AbstractCommercial, shipborne tourism along the Antarctic Peninsula grew exponentially between 1989–90 and 2007–08, raising concern about the impact such activity may have on the environment of the region. Previous analyses of Antarctic tourism have focused narrowly on patterns of visitation and potential impacts at terrestrial landing sites. Here, using 19 years of passenger landing statistics and five years of reconstructed ship itineraries, we explore patterns of tourism activities in the Antarctic Peninsula region using a spatially explicit network theory analysis of ship itineraries. We find that passenger landings and marine traffic are highly concentrated at a few specific locations and that growth in tourism activity occurred disproportionally rapidly at these sites relative to growth in visitation of the Peninsula as a whole. We conclude by discussing the pros and cons of spatially concentrated tourism activity and the associated implications for ecosystem management.

scholarly journals Subseasonal hydrometeorological ensemble predictions in small- and medium-sized mountainous catchments: benefits of the NWP approach

2019 ◽  
Vol 23 (1) ◽  
pp. 493-513 ◽  
Author(s):  
Samuel Monhart ◽  
Massimiliano Zappa ◽  
Christoph Spirig ◽  
Christoph Schär ◽  
Konrad Bogner
Keyword(s):  
Initial Conditions ◽  
Weather Prediction ◽  
Added Value ◽  
Ensemble Prediction ◽  
Late Winter ◽  
Streamflow Prediction ◽  
Ensemble Prediction System ◽  
Mountainous Regions ◽  
Temperature And Precipitation ◽  
Nwp Model

Abstract. Traditional ensemble streamflow prediction (ESP) systems are known to provide a valuable baseline to predict streamflows at the subseasonal to seasonal timescale. They exploit a combination of initial conditions and past meteorological observations, and can often provide useful forecasts of the expected streamflow in the upcoming month. In recent years, numerical weather prediction (NWP) models for subseasonal to seasonal timescales have made large progress and can provide added value to such a traditional ESP approach. Before using such meteorological predictions two major problems need to be solved: the correction of biases, and downscaling to increase the spatial resolution. Various methods exist to overcome these problems, but the potential of using NWP information and the relative merit of the different statistical and modelling steps remain open. To address this question, we compare a traditional ESP system with a subseasonal hydrometeorological ensemble prediction system in three alpine catchments with varying hydroclimatic conditions and areas between 80 and 1700 km2. Uncorrected and corrected (pre-processed) temperature and precipitation reforecasts from the ECMWF subseasonal NWP model are used to run the hydrological simulations and the performance of the resulting streamflow predictions is assessed with commonly used verification scores characterizing different aspects of the forecasts (ensemble mean and spread). Our results indicate that the NWP-based approach can provide superior prediction to the ESP approach, especially at shorter lead times. In snow-dominated catchments the pre-processing of the meteorological input further improves the performance of the predictions. This is most pronounced in late winter and spring when snow melting occurs. Moreover, our results highlight the importance of snow-related processes for subseasonal streamflow predictions in mountainous regions.

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