0000000000922552
AUTHOR
Inese Latkovska
Atmosfēras nokrišņu daudzuma noteikšana Latvijas upju baseiniem
Bakalaura darba tēma ir „Atmosfēras nokrišņu daudzuma noteikšana Latvijas upju baseinos hidroloģiskajiem aprēķiniem”. Darba mērķis ir noteikt atmosfēras nokrišņu daudzumu Latvijas upju baseiniem, izmantojot dažādu metodiku, kas balstīta uz Ģeogrāfiskajām Informācijas Sistēmām. Literatūras analīzē tiek apskatīti galvenie virzieni, kur Ģeogrāfiskās Informācijas Sistēmas ir kā nozīmīgs atbalsta instruments hidroloģisko jautājumu risināšanai. Aprakstītas plašāk pielietotās atmosfēras nokrišņu noteikšanas metodes, kā arī raksturots nokrišņu sadalījums Latvijā. Darba pētnieciskajā daļā tiek raksturoti un analizēti meteoroloģisko un hidroloģisko novērojumu staciju dati, kā arī analizētas atmosfēra…
Forecasted changes in the climate and the river runoff regime in Latvian river basins
The hydrological model HBV (Hydrologiska Byråns Vattenbalansavdelning model) has been applied to six river basins in Latvia to assess climate change and its impacts on the river runoff regime at the end of the 21st century. Climate change has been predicted by applying the regional climate model RCAO with the driving boundary conditions from the global general circulation model HadAM3H applied for the IPCC scenarios A2 and B2 and the following time periods: 1961–1990 (control) and 2071–2100 (scenario). Changes have been found under both scenarios. Major changes in the future hydro-climate data were forecasted according to the A2 scenario, where the trends of increase are identified for the …
Long-term changes in the water temperature of rivers in Latvia
Abstract The study describes the trends of monthly mean water temperature (from May to October) and the annual maximum water temperature of the rivers in Latvia during the time period from 1945 to 2000. The results demonstrated that the mean water temperatures during the monitoring period from May to October were higher in the largest rivers (from 13.6 °C to 16.1 °C) compared to those in the smallest rivers (from 11.5 °C to 15.7 °C). Similar patterns were seen for the maximum water temperature: in large rivers from 22.9 °C to 25.7 °C, and in small rivers from 20.8 °C to 25.8 °C. Generally, lower water temperatures occurred in rivers with a high groundwater inflow rate, for example, in river…
Long-term changes in hydrological regime of the lakes in Latvia
Changes in the hydrological regime of the lakes of Latvia depend on natural and anthropogenic causes. This publication summarises the results of the research on the long-term changes in the water level, thermal and ice regimes in the seven largest lakes of Latvia: Liepājas, Usma, Ķīšezers, Burtnieks, Rāzna, Sventes and Lielais Ludzas, and their regional specifics from 1926 to 2002. For most of the studied lakes, the water level has been regulated, except for the lakes Liepājas, Burtnieks and Ķīšezers. Global climate warming has caused considerable changes in the hydrological regime of the lakes during the last decades and the surface water temperature has increased. At the same time, the nu…
Latvijas upju hidroloģiskā režīma ilgtermiņa un sezonālās izmaiņas
Elektroniskā versija nesatur pielikumus
Changes in Latvian river discharge regime at the turn of the century
The study deals with turn-of-the-century changes in the total annual river runoff distribution and high and low flows in Latvia, covering river basins within four hydrological districts which vary according to size and physiographical conditions. Mathematical statistical methods were applied in the analysis of river discharge data series for two study periods of 1951–2009 and 1881–2009. The present results confirm the basic statement concerning the Baltic countries that major significant changes in river runoff during the last two decades have occurred between spring (decrease) and winter (increase) seasons. Mostly insignificant changes in summer runoff and significant/insignificant changes…
Latvijas upju baseinu klimata un noteces režīma izmaiņas 21.gadsimta beigās
Maģistra darba tēma ir „Latvijas upju baseinu klimata un noteces režīma izmaiņas 21. gadsimta beigās”. Darba mērķis ir izpētīt konceptuālā lietus-noteces modeļa HBV pielietošanas iespējas hidroloģisko procesu simulēšanā un Latvijas upju baseinu hidrometeoroloģisko parametru izmaiņas nākotnes klimata apstākļos. Literatūras analīzē aplūkotas hidroloģiskās modelēšanas pielietošanas iespējas un sniegts hidroloģisko modeļu raksturojums. Tāpat aplūkoti dažādi klimata modeļi un nākotnes scenāriji, kā arī citi pētījumi par klimata izmaiņām un to ietekmi uz upju noteci Baltijas jūras sateces baseina DA daļā. Darba pētnieciskajā daļā hidroloģisko procesu simulēšanai Latvijas upju baseinos, balstoties…
Long-term changes of the ice regime of rivers in Latvia
The ice regime of rivers is considered a sensitive indicator of climate change. This paper summarises the results of research on the long-term changes in the ice regime parameters under changing climate conditions and their regional peculiarities in Latvia from 1945 to 2012. The ice cover duration on Latvian rivers has decreased during recent decades. The research results demonstrated that there is a positive trend as regards the formation of the ice cover and in 31.8% of the cases the trend is statistically significant at p < 0.05. As regards the breaking up of ice, there is a statistically significant negative trend in 93.2% of the cases at p < 0.05. This indicates an earlie…