Statistična analiza padavin

Poglič, Nina (avtor), Šraj, Mojca (mentor), Škapin Rugelj, Marjeta (komentor)

Padavine sodijo med osnovne podnebne spremenljivke. Spremenljivost količine padavin ima velik vpliv na vse panoge, ki so povezane z vodo in njeno rabo (kmetijstvo, hidroenergetika, gradbeništvo itd.). Ugotavljanje trenda padavin je pomembno za razumevanje podnebnih sprememb in zaznavanje dejavnikov, ki povzročajo spremembe v višini padavin. V diplomski nalogi je narejena statistična analiza padavin za obdobje 1970-2017, s prikazom maksimumov, minimumov in kvartilov mesečnih vsot padavin, grafični prikaz povprečnih mesečnih padavin, histogram dnevnih padavin in graf letnih vsot z linearno trendno črto. Statistična analiza zajema 20 meteoroloških oz. padavinskih postaj in je narejena s pomočjo programskega orodja R. Za obravnavane postaje je izdelan tudi Mann-Kendallov test trendov mesečnih maksimumov, letnih maksimumov in letnih padavin. Nadalje pa je bila izdelana še analiza sezonskosti dnevnih maksimalnih količin padavin. Rezultati analize trendov mesečnih in letnih padavin kažejo na naraščajoč trend, ki pa je skoraj za vse postaje statistično neznačilen z izbrano stopnjo značilnosti 0,1. Mann- Kendallov test trendov je bil izdelan tudi za dneve brez padavin (t.i. suhi dnevi). Ugotovljeno je bilo, da je trend suhih dni za večino postaj naraščajoč in statistično neznačilen z izbrano stopnjo značilnosti 0,1. Z namenom ugotovitve vpliva geografske lege na količino padavin je bila izdelana analiza odvisnosti letnih količin padavin od nadmorske višine in oddaljenosti od morja. Analiza je pokazala, da ima na raznolikost količine padavin in posledično pridobljene rezultate trendov velik vpliv prevladujoče »gibanje« padavin in topografija Slovenije. Ugotovljeno je bilo, da določena stopnja sezonskosti za vse obravnavane postaje obstaja, najbolj izrazita pa je na postaji Polički Vrh. Rezultati analize sezonskosti so pokazali, da je bilo največ letnih maksimumov dnevnih padavin v poletnih in jesenskih mesecih, kar nakazuje, da velik del Slovenije leži na območju s celinskim podnebjem.

• Jezik: Slovenski jezik
• Ključne besede: padavine, Mann-Kendallov test, trendi, sezonskost, programsko orodje R
• Vrsta gradiva: Diplomsko delo/naloga
• Organizacija: FGG - Fakulteta za gradbeništvo in geodezijo
• Leto izida: 2020
• PID: 20.500.12556/RUL-114771
• Datum objave v RUL: 08.03.2020

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Statistical rainfall analysis

Izvleček

Rainfall is one of the basic climate variables. Variability of the rainfall has a great impact on disciplines related to water (e.g., farming, hydropower, construction etc.). Identification of rainfall trend is important for understanding of the climate change or variability impact and detecting the factors, which cause changes in rainfall characteristics. Diploma thesis consists of statistical analysis of rainfall, which includes the presentation of maximum, minimum and quartile of monthly rainfall sum, graphic presentation of average monthly rainfall, histogram of daily rainfall and the graph of annual rainfall with linear trend line. The statistical analysis is carried out using software R and includes 20 rainfall and meteorological stations in Slovenia for the period 1970-2017. Furthermore, for the selected stations the Mann-Kendall test of the monthly and yearly maximum trend and yearly rainfall trend is performed. Additionally, the seasonality analysis of daily maximum amounts of precipitation was conducted. The results of analysis indicate that monthly and annual precipitation amounts show an increasing trend, however the detected trend is statistically insignificant with selected significance level of 0,1 for almost all stations. Mann-Kendall's trend test was also performed for days without precipitation (i.e. dry days). It was found that the dry days trend for most stations is increasing and statistically insignificant with the selected significance level of 0,1. In order to determine the influence of the stations geographical location on the amount of precipitation, the analysis of the dependence of annual rainfall amounts to the altitude and distance from the sea was investigated. The variability of the rainfall amount and obtained trend results are probably consequence of the strong natural geographic diversity of Slovenia. It was found that some degree of seasonality exists for all analyzed stations, and seasonality is most significant for the Polički Vrh station. The results of the seasonal analysis showed that the highest annual maximum daily precipitation was detected during the summer and autumn, which suggests that a large part of Slovenia has continental climate characteristics.

• Ključne besede: rainfall, Mann-Kendall test, trends, seasonality, R software