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The purpose of the paper is to evaluate what constitutes car accidents and identify the territorial dispersion with the highest number of collisions. In this paper the main forces and circumstances causing automobile accidents in Lithuania are investigated referring to the general analysis of road traffic collision, while the examination of their territorial dispersion is done taking into consideration the following indicators: the number of the accidents and the statistics of injuries and deaths in 2000-2012. The chosen method of black spots enabled to reveal the roads where people were most often injured or killed during the motor vehicle collisions. In this paper much attention is given to combined analysis of the causes of motor vehicle collision. The examined combined approach towards the phenomenon assisted the investigation of the causes involving not only external aspects of the issues of road traffic safety but also the inner reasons of the phenomenon analysed. [ABSTRACT FROM AUTHOR]

This paper seeks to classify the lakes of Lithuania by their functional use. The paper is based on the previous research experience. The classification is prepared with the view that currently the basic functions of Lithuanian lakes are considered to be recreation and communication while additional ones are commercial fishing, industry and energy, agriculture and domestic use. The following categories of lakes were differentiated according to the efficiency of functional usage: category I - lakes in which recreational activities are developed; category II - lakes which are used for communication and commercial fishing; category III - lakes that are used for energy and in industry, agriculture and for domestic needs. In order to put the lakes into groups the essential factors that have the greatest impact on the lake function choice were determined. It was found that the lake area and landscape of the lake shore mostly influence the choice of spectrum of potential lake functions. It is noted that the functional usage of a lake grows with the increase of a lake area (in particular the change is prominent at the 50 hectare threshold) and the change of the landscape of a lake shore in the following sequence: swamp ? forest ? grassland ? populated area. These factors (lake area and the landscape of a lake shore) are 1 level factors. The conservation status of the territory and the accessibility of a lake by road have less impact on the functional use of a lake. The lakes that are difficult to access by road usually have a narrower potential of functional use. The lakes that are in protected territories formally lose some of their potential functions, but in reality the ban to perform them is often neglected. The access of lakes by roads and conservation status of territory are considered to be the factors of the 2 level in terms of the choice of development of potential lake functions. It was found that at present Lithuanian lakes can be divided into three types according to their functional usage. The lakes with swampy shores that have very limited possibilities of usage are attributable to the first type. The lakes of second type are smaller than 50 hectares and their shores are dominated by forests or grasslands. Lakes of this type are most suitable for the development of recreational activities. The third type includes lakes smaller than 50 hectares that are by populated areas and the lakes that are bigger than 50 hectares. These water bodies have the most extensive spectrum of potential functions but they often do not correspond to the conservation status of the territory and general environmental regulations. It is concluded that it is necessary to take the following measures to develop the functional usage of lakes in Lithuania in an orderly way: a) to consider lake priority functions, the ones which have the lowest and most manageable impact on the lake ecosystem, b) to try to adjust the range of lake functions in such a way that they are consistent with each other (this is particularly important for the lakes that are by protected areas, towns and large lakes which currently perform many functions), c) to regulate the system of lake management and protection according to the situation in Lithuania (current EU directives are often not suitable for the conditions of the country). [ABSTRACT FROM AUTHOR]

The type and character of precipitation reaching earth's surface mainly depend on the thermodynamic state of the troposphere. Numerous thermal parameters are used to determine precipitation type, among them the depth of the thermal layer, freezing height, inversion levels, critical temperatures of isobaric surfaces, etc. The study focuses on relations between thickness and temperature parameters above the canopy layer and the precipitation type. The study period covers 1997-2006 cold seasons (November-March). The parameters used in the study are: 1000-500 hPa integrated thickness (ST1000500) and partial thickness ST1000850, ST850700, ST850500, ST700500; also 925 hPa, 850 hPa, 700 hPa, 500 hPa level temperature (T925, T850, T700, T500). Precipitation type data for Lithuanian territory were compiled using the network of the National Weather Board (LHMT) first-order stations (Biržai, Kaunas, Klaipėda, Varėna, and Vilnius). Free atmosphere data were obtained from NCeP 2 database (http://nomad3.ncep.noaa.gov/ncep-data/) and the Kaunas radio-sounding station. The threshold values of the thermal parameters were calculated using one standard deviation (SD) statistical model. If the derived thickness or temperature fall into the ±SD interval, then the value is classified as varying around "normal" ("normal" pertains to statistical representation) (Heppner, 1992). All precipitation types were grouped into three categories: snow (snow, ice pellets), rain (rain, drizzle) and winter mix (snow with rain, sleet). The first part of the paper presents typical values of thickness and temperature for different precipitation types and their spatial and temporal variability. Integrated thickness (ST1000500) near the coastline seems to be always about 23 gpm thinner for snow pattern than in the rest of Lithuania. For rain, ST1000500 appears to be almost constant in the whole territory. However, thickness parameters show a large spatial and temporal variation. The mean values of integrated thickness related to snow type patterns are highest in late autumn, later they start to drop and in early spring reach the lowest values. There is no such seasonal trend for rain patterns: thickness values are also highest in late autumn, but in mid-winter they become minimal, while at the end of winter again begin to rise. A similar trend was observed for typical temperatures at the standard layers. The threshold values of the thermal parameters are presented in the second part of the paper. These values should be used in the diagnosis of precipitation type. The best indices in the diagnosis appear to be ST1000500 and ST1000850. These parameters indicate the correct number of precipitation type events in 82% of show cases and in 85% of rain cases. Snow is most likely to occur when ST1000500 < 5285 gpm and ST1000850 < 1285 gpm, while rain is most probable at ST1000500 > 5285 gpm and ST1000850 > 1295 gpm. The best temperature indices appear to be at the 925 hPa level (T925).… [ABSTRACT FROM AUTHOR]

The thesis issues deal with the Lithuanian lake catalog credibility potential to reveal infallible information considering lake morphometric parameters change evaluation in due time. The paper analyses Lithuanian lakes with an area greater than 50 ha, morphometric parameters (water level altitude a, area A and length L of the shoreline). In the catalogs, the data on Lithuanian lakes differs in content and quality, yet has one thing in common - morphometric indices calculated according to the maps. In this work the methodology used for comparison of lakes morphometric indices was chosen according to specific data used in the analysis. Specific data was mostly selected due to the peculiarities of primary sources of information - such as lakes registers. This allows the methodology for the analysis of data to be divided into three main stages: 1) selection of information sources, 2) sampling, and 3) selection of analytical methods. Most cadastral information about lakes presenting data sources differs significantly in volume, used methods, and the quality of maps. Therefore, some of them may not even be compared to each other. The most appropriate pieces for comparison were those of 1953 and 1964 lake cadastres. Unfortunately, not all data is comparable in lake numbers as well as in morphometric parameter values. However, most of these differences can be easily explained. The main parameters to evaluate were the potential changes that occurred among a lake area (A) and a shoreline length (L). Additionally, these parameters were examined as a sequence to water level change (Δa). It was ascertained that all the investigated lake characteristics declined during the period between cadastres. Correlation coefficients (rδA-dL, rδA-Δa, rδL-Δa) characterizing relations between changes were positive, therefore proving that there might have been more similar character changes. The analysis of data variation overlap shows that the most reliable morphometric indicator of early lakes is the area of a lake. The change of the latter was often coherent to other parameters (altitude, shoreline length) alterations. The comparison between other characteristics shows that when the actual altitude of water level is increasing, negative changes in the number of coincidences decrease. This means that morphometric indices of upper lakes declined significantly less often in comparison to lakes which are located in the lower regions. Herewith, change in the distribution of tendencies overlap in various area intervals - as well as the correlation analysis - shows that changes in number are almost unlinked with a lake area. According to analysis of lake physical data congruence within time, it is stated that there are no relations between parameters characterizing lakes hydrographic activity and morphometric characteristics of lake changes. [ABSTRACT FROM AUTHOR]

Data from Road Weather Information Systems (RWIS) automatic stations have been used all over the world for a wider range of purposes than just icy (slippery) road surface forecasts. The aim of this paper was to apply Lithuanian RWIS data to spatial temperature field analysis. The research area is central Lithuania, consisting mainly of Kaunas and the neighboring districts. The data used in the research were obtained from two different types of stations: automatic RWIS stations and meteorological stations. This information was compiled from the archives in Lithuanian Hydrometeorological Service and Lithuanian Road Administration. The chosen time period was 2007 and 2009 (GMT). Firstly, the evaluation of data suitability for spatial analysis was performed. Secondly, the analysis itself was done by drawing two types of maps representing the monthly mean temperature and a map of the yearly amplitude (year 2009). The first mean monthly temperature map type included data only from meteorological stations, whereas the second type was made combining data from both meteorological stations and RWIS. The chosen method for data interpolation was based on spline functions. It was found that if RWIS data is included into temperature field, a vast gradient appears between Babtai and Gynėvė RWIS stations. This results in considerable disparity in temperature zones in the northern area. It was also noted that there is a relatively smaller temperature anomaly in the southern region near Dzūkai Highlands and a slight positive temperature anomaly in the south-eastern part of the region during winter months. It was concluded that RWIS stations represent their background temperature field well and their data can be used in further analyses. Nevertheless, it is recommended to use data from as many stations as possible and to take into consideration the impact of dependency on the local environment and microclimate. [ABSTRACT FROM AUTHOR]

The paper is based on the classification of river waters into salmonid and cyprinid. The main objective is to assess the compliance of Lithuanian river water temperature with the ecological requirements, referring to the temperatures mentioned in the organic classification. Data of river hydrological stations for the period 2003-2007 were used to evaluate water temperature. We measured what average decimal pointed and maximum water temperatures correspond to the temperatures mentioned in organic classification; river sections were grouped according to relationship between the average and maximum temperatures nature; organic temperature date of different river section groups. After various calculations, the rivers were divided into three groups according to the slope and the average temperature, and it was shown that correlation coefficients of the river groups are in the range of reliability when set significance level is 0.01 (1%). According to the provisions of the Freshwater Fish Directive, the water surface quality was divided into five classes: 1) very good, 2) good, 3) satisfactory, 4) poor, and 5) very bad. The data analysis of river waters and the average and maximum temperatures of a five-year period (2003-2007) showed that from the hydrological stations of 47 rivers in 14 water quality was very good / good, in 28 satisfactory and in 5 poor. Very poor water condition was not found in the analyzed rivers. The examination of the river groups crossing over 18 °C, 21.5 °C and 24 °C temperatures revealed that each of the river groups showed that the crossing dates are available at different times as the rivers have been classified in accordance with the slope values and temperature values. [ABSTRACT FROM AUTHOR]

In the paper, two indexes - the Standardized Precipitation Index (SPI) and the Seleninov Hydrothermal Coefficient (HTC) - were used for the identification of droughts. SPI was used for the whole period. Also, summer periods were analyzed using the HTC and SPI. Droughts and dry periods were identified using different SPI time scales: SPI1, SPI3, SPI6, SPI9, SPI12, SPI24, SPI48 and SPI60. Different time scales might define different types of droughts. The SPI values obtained with and without data set reconstruction were compared. The results showed that it was better to use data sets with data reconstruction. A comparison of the SPI index in different time scales and of the SPI and HTC values (Table 6) showed the highest correlation between SPI3 and summer HTC and between one-month HTC and SPI1. The SPI as a time scale is lower, the greater the shorter-term droughts recorded. By contrast, the SPI time scale is longer if there are less droughts but they are longer (Table 7). This tendency is characteristic of droughts of varying intensity. However, a number of extremely dry and extremely wet months according to SPI long time scale calculations aren't defined as extremely dry according to SPI low-step scale calculations. Extremely dry months (except SPI48) according to all time scales (SPI1, SPI3, SPI6, SPI9, SPI12, SPI24, SPI48, SPI60) were recorded only in 1909. The lowest SPI values across all the time steps were fixed at the beginning of the last century (Table 4). The number of extremely dry months was higher than that of extremely wet ones across all the time steps during the study period (1891-2010) (Fig. 3). The driest summer months were fixed in the first thirty years of the study period (in 1891-1920) in SPI3, SPI6, SPI9, SPI 12, SPI48, SPI60 time steps, while in the SPI1 time step the driest months were fixed in the last thirty years (1981-2010) (Fig. 4). There is a tendency that the low values of the SPI index are recorded more frequently for SPI in low time steps over the past decades in the summer months. According to both SPI3 and all summer HTC values, three extremely dry summers - 1914,1964 and 1992 - were identified. [ABSTRACT FROM AUTHOR]

The main object of the paper article is water resources of Lithuanian rivers, which were calculated using a long data series of the runoff. Water resources are based on the balance equation. This means that this equation includes only the runoff formed in the Lithuanian territory, from neighboring countries to Lithuania and through them into the sea. The average and dry annual water resources have been calculated at a 95% probability. The average perennial water resources of Lithuanian rivers are 24.844 km³ / year, of them 8.883 km³ / year is the transit from Belarus, Poland and Kaliningrad Region to Lithuania, 15.961 km³ / year is formed in Lithuania and 7.471 km³ / year are effluents through Latvia into the Baltic Sea from Kaliningrad Region into the Curonian Lagoon. The Nemunas basin floats 21.501 km³ / year to the Curonian Lagoon. The present water resources are by 4.5% less in comparison with water resources of in the year 1996. Cyclic water change is typical of the Lithuanian rivers. The Nemunas-Smalininkai hydrological station has noted 7 cycles in a long data series. The average term of a cycle is 27 years (14 years of a wet and 13 years of a dry period). The runoff of the Nemunas river differs in the duration of dry and wet periods (by about 16%). The runoff of rivers in Southeast and Western Lithuania differs by 21-23% and in Middle Lithuania by 28%. The long data series of the Nemunas-Smalininkai runoff have a negative trend because of a decrease in the last four decades. The runoff measured by this water management station consists of river runoff from the southeastern and middle parts of Lithuania. The annual runoff has a positive trend in the majority of Western Lithuanian rivers in the period 1961-2003. The minimum runoff of a dry period shows no trend in most Lithuanian rivers, except Western Lithuania where a positive trend was estimated in the period 1961-2003. [ABSTRACT FROM AUTHOR]

The scientific heritage of Academician Vytautas Gudelis contains books, scholarly and social papers, actual interviews, notes and remarks, manuscripts and correspondence. The article aims to review his fundamental books in which the subject-matter and contents reflect his competency to deal with actual problems, to summarize results of investigations, to get across his widths of view for society. The first books written by V. Gudelis in the 1960s were like streamlets yet, like small rivulets in their headwaters, like the Nemunas or the Neris in their sources, which gradually develop into a powerful stream in which to be alive and well was Professor's mission. This stream embraces the Curonian Lagoon, the Baltic Sea, and the Curonian Spit - their past, their development, their present and future. [ABSTRACT FROM AUTHOR]