scholarly journals The Annual Number of Days with Precipitation and Its Assurance Degree During 1961–2016, in Maramureş County

2018 ◽  
Vol 12 (1) ◽  
pp. 229-237
Author(s):  
Șerban Eugenia
Keyword(s):  
Temporal Variability ◽  
Linear Trend ◽  
The Other ◽  
Annual Number ◽  
Spatial And Temporal Variability ◽  
Baia Mare ◽  
Precipitation Increase ◽  
The Mean ◽  
Weather Stations

Abstract The paper analyzed the annual number of days with precipitation from 4 weather stations located in Maramureş County, during 1961-2016. The frequency of these days, their spatial and temporal variability, the decennial distribution of the number of days with precipitation, the trend and the assurance degree of the annual number of days with precipitation were also studied. The result was that in Maramureș County, between 157 and 194 days with precipitation occur on average per year. The mean annual number of days with precipitation increases from west to east, as the altitude of landforms increases, but also from south to north, as latitude increases. The analysis of the rainy and dry yearly intervals reveals the appearance of several extreme years towards the end of the analyzed period, in the last decade and a half (2000-2016). The linear trend of the annual number of days with precipitation is slightly increasing at the lowest station Baia Mare and decreasing at the other stations. The wettest decades were the 5th (2001-2010) and the 1st (1961-1970), and the driest decades were the 6th (2011-2016) and the 3rd (1981-1990). On the territory of Maramureş County, the values corresponding to the characteristic assurances (1, 2, 5, 10, 20, 25, 50, 80 and 100%) of the annual number of days with precipitation increase from west to east and from south to north. Once every 100 years, between 225 and 273 days with precipitation can occur in Maramureș.

scholarly journals Spatial variability and trends of the rain intensity over Greece

2010 ◽  
Vol 26 ◽  
pp. 65-69 ◽  
Author(s):  
H. D. Kambezidis ◽  
I. K. Larissi ◽  
P. T. Nastos ◽  
A. G. Paliatsos
Keyword(s):  
Confidence Level ◽  
Temporal Variability ◽  
Interpolation Method ◽  
Kendall Test ◽  
Kriging Interpolation ◽  
Spatial And Temporal Variability ◽  
Rain Intensity ◽  
Kriging Interpolation Method ◽  
Bartlett Test ◽  
The Mean

Abstract. In this study, the spatial and temporal variability of the mean annual rain intensity in Greece are examined during a 41-year period (1962–2002). The meteorological datasets concern monthly rain amounts (mm) and the respective monthly durations (h) recorded at thirty two meteorological stations of the Hellenic National Meteorological Service, which are uniformly distributed on Greek territory, in order to calculate the mean monthly rain intensity. All the rain time series used in the analysis were tested by the application of the short-cut Bartlett test of homogeneity. The spatial distribution of the mean annual rain intensity is studied using the Kriging interpolation method, while the temporal variability, concerning the mean annual rain intensity trends along with their significance (Mann-Kendall test), is analysed. The findings of the analysis show that statistically significant negative trends (95% confidence level) appear mainly in the west sub-regions of Greece, while statistically significant positive trends (95% confidence level) appear in the wider area of Athens and the complex of Cyclades Islands. Further analysis concerning the seasonal rain intensity is needed, because there are different seasonal patterns, taking into account that, convective rain in Greece occurs mainly within the summer season.

scholarly journals Connecting European snow cover variability with large scale atmospheric patterns

2010 ◽  
Vol 26 ◽  
pp. 93-97 ◽  
Author(s):  
E. Bartolini ◽  
P. Claps ◽  
P. D'Odorico
Keyword(s):  
Climate Variability ◽  
Snow Cover ◽  
Temporal Variability ◽  
Large Scale ◽  
Management Strategies ◽  
The Other ◽  
The Arctic ◽  
Spatial And Temporal Variability ◽  
East Atlantic ◽  
The North

Abstract. Winter snowfall and its temporal variability are important factors in the development of water management strategies for snow-dominated regions. For example, mountain regions of Europe rely on snow for recreation, and on snowmelt for water supply and hydropower. It is still unclear whether in these regions the snow regime is undergoing any major significant change. Moreover, snow interannual variability depends on different climatic variables, such as precipitation and temperature, and their interplay with atmospheric and pressure conditions. This paper uses the EASE Grid weekly snow cover and Ice Extent database from the National Snow and Ice Data Center to assess the possible existence of trends in snow cover across Europe. This database provides a representation of snow cover fields in Europe for the period 1972–2006 and is used here to construct snow cover indices, both in time and space. These indices allow us to investigate the historical spatial and temporal variability of European snow cover fields, and to relate them to the modes of climate variability that are known to affect the European climate. We find that both the spatial and temporal variability of snow cover are strongly related to the Arctic Oscillation during wintertime. In the other seasons, weaker correlation appears between snow cover and the other patterns of climate variability, such as the East Atlantic, the East Atlantic West Russia, the North Atlantic Oscillation, the Polar Pattern and the Scandinavian Pattern.

scholarly journals Changes in glacier equilibrium-line altitude in the western Alps from 1984 to 2010: evaluation by remote sensing and modeling of the morpho-topographic and climate controls

2013 ◽  
Vol 7 (5) ◽  
pp. 1455-1471 ◽  
Author(s):  
A. Rabatel ◽  
A. Letréguilly ◽  
J.-P. Dedieu ◽  
N. Eckert
Keyword(s):  
Temporal Variability ◽  
Satellite Images ◽  
Linear Trend ◽  
Winter Precipitation ◽  
Western Alps ◽  
Equilibrium Line ◽  
Precipitation Pattern ◽  
Spatial And Temporal Variability ◽  
Climate Variables ◽  
Equilibrium Line Altitude

Abstract. We present time series of equilibrium-line altitude (ELA) measured from the end-of-summer snow line altitude computed using satellite images, for 43 glaciers in the western Alps over the 1984–2010 period. More than 120 satellite images acquired by Landsat, SPOT and ASTER were used. In parallel, changes in climate variables, summer cumulative positive degree days (CPDD) and winter precipitation, were analyzed over the same time period using 22 weather stations located inside and around the study area. Assuming a continuous linear trend over the study period: (1) the average ELA of the 43 glaciers increased by about 170 m; (2) summer CPDD increased by about 150 PDD at 3000 m a.s.l.; and (3) winter precipitation remained rather stationary. Summer CPDD showed homogeneous spatial and temporal variability; winter precipitation showed homogeneous temporal variability, but some stations showed a slightly different spatial pattern. Regarding ELAs, temporal variability between the 43 glaciers was also homogeneous, but spatially, glaciers in the southern part of the study area differed from glaciers in the northern part, mainly due to a different precipitation pattern. A sensitivity analysis of the ELAs to climate and morpho-topographic variables (elevation, aspect, latitude) highlighted the following: (1) the average ELA over the study period of each glacier is strongly controlled by morpho-topographic variables; and (2) the interannual variability of the ELA is strongly controlled by climate variables, with the observed increasing trend mainly driven by increasing temperatures, even if significant nonlinear, low-frequency fluctuations appear to be driven by winter precipitation anomalies. Finally, we used an expansion of Lliboutry's approach to reconstruct fluctuations in the ELA of any glacier of the study area with respect to morpho-topographic and climate variables, by quantifying their respective weight and the related uncertainties in a consistent manner within a hierarchical Bayesian framework. This method was tested and validated using the ELA measured on the satellite images.

scholarly journals Evaluación de dos modelos para la estimación de la evapotranspiración de referencia con datos CERES

2018 ◽  
pp. 87 ◽  
Author(s):  
F. Carmona ◽  
M. Holzman ◽  
R. Rivas ◽  
M.F. Degano ◽  
E. Kruse ◽  
...  
Keyword(s):  
Temporal Variability ◽  
Reference Evapotranspiration ◽  
Important Variable ◽  
Spatial And Temporal Variability ◽  
Suitable Alternative ◽  
Pampean Region ◽  
Daily Scale ◽  
Weather Stations ◽  
Good Agreement

<p>Evapotranspiration is the most important variable in the Pampas plain. Information provided by sensors onboard satellite missions allows represent the spatial and temporal variability of evapotranspiration, which cannot be achieved using only measurements of weather stations. In this work, the Priestley and Taylor (PT) and FAO Penman Monteith (FAO PM) equations were adapted to estimate the reference evapotranspiration, ET<sub>0</sub> , using only CERES satellite products (SYN1 and CldTypHist). In order to evaluate the reference evapotranspiration from CERES, a comparison with in situ measurements was conducted. We used ET data provided by the Oficina de Riesgo Agropecuario, corresponding to 24 stations placed in the Pampean Region of Argentina (2001-2016). Results showed very good agreement between the estimates with CERES products and in situ values, with errors between ±0.8 and ±1.1 mm d–<sup>1 </sup>and r<sup>2</sup>  greater than 0.75  at daily scale, and errors between ±14  and ±19  mm month<sup>–1</sup>  and r<sup>2</sup>   greater than 0.9, at monthly scale better results were obtained with adapted model FAO PM than PT. Finally, ET<sub>0</sub> monthly maps for the Pampean Region of Argentina were elaborated, which allowed knowing the temporal-spatial variation in the validation area. In conclusion, the methods presented here are a suitable alternative to estimate the reference evapotranspiration without requiring ground measurements.</p>

scholarly journals Spatial and temporal variability of seed bank resulting from overgrowing of xerothermic grassland

2011 ◽  
Vol 77 (2) ◽  
pp. 157-166 ◽  
Author(s):  
Joanna Czarnecka
Keyword(s):  
Plant Communities ◽  
Seed Bank ◽  
Temporal Variability ◽  
The Other ◽  
Spatial And Temporal Variability ◽  
Bush Encroachment ◽  
Seed Number ◽  
Grassland Vegetation ◽  
Dynamic Plant ◽  
Qualitative Changes

The aim of my study was to determine changes in the seed bank and vegetation during the process of overgro-wing of the xerothermic grassland situated on the slopes of the White Mountain (349 m a. s. l., the Central Roztocze Region, South-Eastern Poland). I also examined whether the changes of vegetation can be predicted if we know the structure of the burned seed flora. To achieve this goal I used two sets of data: one collected from three different environments (grassland, brushwood and woodland) at the same time (toposequence), and the other collected twice from the same place at the interval of seven years (chronosequence). I stated that the appearance of even a small number of ornitochorous seeds and their seedlings can be treated as a signal that the bush encroachment will accelerate. Seed number seems to decrease during succession in the analysed sequence of plant communities. The total number of species in the seed bank did not change in the most dynamic plant communities: grassland and brushwood, and it was significantly higher there than in the seed bank of woodland. During the time of observation, the most important quantitative and qualitative changes took place in grassland vegetation, which is more similar to brushwood vegetation now than it was at the beginning of the study.

Multi-Center Study of Thromboplastin Calibration Precision – Influence of Reagent Species, Composition, and International Sensitivity Index (ISI)

1993 ◽  
Vol 69 (01) ◽  
pp. 035-040 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Oral Anticoagulants ◽  
International Normalized Ratio ◽  
The Other ◽  
World Health ◽  
Rabbit Brain ◽  
Sensitivity Index ◽  
Bovine Plasma ◽  
Significant Difference ◽  
The Mean ◽  
International Sensitivity Index

SummaryFour thromboplastin reagents were tested by 18 laboratories in Europe, North-America, and Australasia, according to a detailed protocol. One thromboplastin was the International Reference Preparation for ox brain thromboplastin combined with adsorbed bovine plasma (coded OBT/79), and the second was a certified reference material for rabbit brain thromboplastin, plain (coded CRM 149R). The other two thromboplastin reagents were another rabbit plain brain thromboplastin (RP) with a lower ISI than CRM 149R and a rabbit brain thromboplastin combined with adsorbed bovine plasma (RC). Calibration of the latter two reagents was performed according to methods recommended by the World Health Organization (W. H. O.).The purpose of this study was to answer the following questions: 1) Is the calibration of the RC reagent more precise against the bovine/combined (OBT/79) than against the rabbit/plain reagent (CRM 149R)? 2) Is the precision of calibration influenced by the magnitude of the International Sensitivity Index (ISI)?The lowest inter-laboratory variation of ISI was observed in the calibration of the rabbit/plain reagent (RP) against the other rabbit/plain reagent (CRM 149R) (CV 1.6%). The highest interlaboratory variation was obtained in the calibration of rabbit/plain (RP) against bovine/combined (OBT/79) (CV 5.1%). In the calibration of the rabbit/combined (RC) reagent, there was no difference in precision between OBT/79 (CV 4.3%) and CRM 149R (CV 4.2%). Furthermore, there was no significant difference in the precision of the ISI of RC obtained with CRM 149R (ISI = 1.343) and the rabbit/plain (RP) reagent with ISI = 1.14. In conclusion, the calibration of RC could be performed with similar precision with either OBT/79 or CRM 149R, or RP.The mean ISI values calculated with OBT/79 and CRM 149R were practically identical, indicating that there is no bias in the ISI of these reference preparations and that these reference preparations have been stable since their original calibration studies in 1979 and 1987, respectively.International Normalized Ratio (INR) equivalents were calculated for a lyophilized control plasma derived from patients treated with oral anticoagulants. There were small but significant differences in the mean INR equivalents between the bovine and rabbit thromboplastins. There were no differences in the interlaboratory variation of the INR equivalents, when the four thromboplastins were compared.

Prothrombin Time Standardization: Report of the Expert Panel on Oral Anticoagulant Control

1979 ◽  
Vol 42 (04) ◽  
pp. 1073-1114 ◽  
Keyword(s):  
Prothrombin Time ◽  
Expert Panel ◽  
The Other ◽  
Rabbit Brain ◽  
Calibration Constant ◽  
Freeze Dried ◽  
The Mean ◽  
Point Of Intersection ◽  
And Control ◽  
Standardization Report

SummaryIn collaborative experiments in 199 laboratories, nine commercial thromboplastins, four thromboplastins held by the National Institute for Biological Standards and Control (NIBS & C), London and the British Comparative Thromboplastin were tested on fresh normal and coumarin plasmas, and on three series of freeze-dried plasmas. One of these was made from coumarin plasmas and the other two were prepared from normal plasmas; in each series, one plasma was normal and the other two represented different degrees of coumarin defect.Each thromboplastin was calibrated against NIBS&C rabbit brain 70/178, from the slope of the line joining the origin to the point of intersection of the mean ratios of coumarin/normal prothrombin times when the ratios obtained with the two thromboplastins on the same fresh plasmas were plotted against each other. From previous evidence, the slopes were calculated which would have been obtained against the NIBS&C “research standard” thromboplastin 67/40, and termed the “calibration constant” of each thromboplastin. Values obtained from the freeze-dried coumarin plasmas gave generally similar results to those from fresh plasmas for all thromboplastins, whereas values from the artificial plasmas agreed with those from fresh plasmas only when similar thromboplastins were being compared.Taking into account the slopes of the calibration lines and the variation between laboratories, precision in obtaining a patient’s prothrombin time was similar for all thromboplastins.

Platelet Suruival and Function in Rats with Enhanced Thrombotic Tendency

1985 ◽  
Vol 54 (04) ◽  
pp. 739-743 ◽  
Author(s):  
Federica Delaini ◽  
Elisabetta Dejana ◽  
Ine Reyers ◽  
Elisa Vicenzi ◽  
Germana De Bellis Vitti ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Nephrotic Syndrome ◽  
Platelet Function ◽  
Laboratory Tests ◽  
Thrombus Formation ◽  
The Other ◽  
Mean Survival Time ◽  
The Mean ◽  
And Function ◽  
Thrombotic Tendency

SummaryWe have investigated the relevance of some laboratory tests of platelet function in predicting conditions of thrombotic tendency. For this purpose, we studied platelet survival, platelet aggregation in response to different stimuli, TxB2 and 6-keto-PGFlα production in serum of rats bearing a nephrotic syndrome induced by adriamycin. These animals show a heavy predisposition to the development of both arterial and venous thrombosis. The mean survival time was normal in nephrotic rats in comparison to controls. As to aggregation tests, a lower aggregating response was found in ADR-treated rats using ADP or collagen as stimulating agents. With arachidonic acid (AA) we observed similar aggregating responses at lower A A concentrations, whereas at higher AA concentrations a significantly lower response was found in nephrotic rats, despite their higher TxB2 production. Also TxB2 and 6-keto-PGFlα levels in serum of nephrotic rats were significantly higher than in controls. No consistent differences were found in PGI2-activity generated by vessels of control or nephrotic rats.These data show that platelet function may appear normal or even impaired in rats with a markedly increased thrombotic tendency. On the other hand, the significance of high TxB2 levels in connection with mechanisms leading to thrombus formation remains a controversial issue.

Voronoi Analysis of a Soccer Game

2004 ◽  
Vol 9 (3) ◽  
pp. 233-240 ◽  
Author(s):  
S. Kim
Keyword(s):  
Collective Behavior ◽  
Quantitative Assessment ◽  
The Other ◽  
Analysis Method ◽  
Random System ◽  
Soccer Game ◽  
Voronoi Polygons ◽  
The Mean

This paper describes a Voronoi analysis method to analyze a soccer game. It is important for us to know the quantitative assessment of contribution done by a player or a team in the game as an individual or collective behavior. The mean numbers of vertices are reported to be 5–6, which is a little less than those of a perfect random system. Voronoi polygons areas can be used in evaluating the dominance of a team over the other. By introducing an excess Voronoi area, we can draw some fruitful results to appraise a player or a team rather quantitatively.

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