Regional patterns in tropospheric and sea surface temperature (SST) trends are examined for the period 1979 ??01 using MSU, NCEP-NCAR, ECMWF ERA-40 reanalyses, NOAA OI SST, and the CARDS radiosonde data set. Trends are estimated using a nonparametric Mann-Kendall approach. Substantial regional variability in temperature trends is seen in all of these data sets, with the magnitude of the variability (including substantial regions with cooling trends) far exceeding the average warming trend. The global analyses from MSU and the NCAR/NCEP and ECMWF reanalyses are used to identify sampling problems in using the radiosonde network to infer global trends. Analysis of the trends in tropospheric temperature concurrent with trends in SST shows regions where the signs disagree for both surface cooling and warming. Interpretation of these differing trends using the reanalyses suggest that the models used for the reanalyses are simulating the necessary dynamics/thermodynamics thatcould lead to a tropospheric cooling in contrast to a surface warming (and vice versa).

The current literature shows that global climate is changing with temperatures generally increasing, precipitation patterns becoming less predictable and extreme weather events becoming more frequent. However, the literature is often unclear not only about how changes in temperature will affect soil processes but even about how soil temperatures themselves are changing. This thesis has found that soil temperatures over recent decades have increased at rates comparable to air temperatures (average mean of 0.71 in soil and 0.93 °C in air over the total length of the data sets used). There were differences in seasonal trends between soil and air, for example, winter air temperatures increased twice as quickly as spring air temperatures whereas in soil winter and spring temperatures were increasing at similar rates. This highlights potential problems for predicting how soil functions such as biogeochemical cycling will respond to realistic temperature change. In order to assess the effects of changing soil temperatures on particular reactions involved in soil Nitrogen cycling incubation experiments, both short and longer term in the laboratory as well as soil warming in the field were carried out. Realistic warming was found to increase the rates of protease and urease activity during all tests; however, amidase activity was only measurable after the addition of labile carbon and even then showed no temperature sensitivity. This thesis also considered the effect of temperature change on the size and structure of the soil microbial community at these realistic soil temperatures. Both in the lab and the field changes in rates of soil processes (enzyme activity) as a result of temperature change are not accompanied by a change in either size or structure of the microbial community as measured by phospholipid fatty acid analysis, suggesting high levels of functional redundancy within the soil microbial community. The effects of organic matter input in the field were found to have only small effects on the rates of enzyme activity although this was more important during laboratory incubations. Organic matter quality was also important during lab incubations where lower quality organic matter provoked greater enzyme activity in accordance with q-theory; however, there was no evidence for greater temperature sensitivity of low quality organic matter. The size and structure of the microbial community, both in the field and in the lab, were not affected by either the rate of organic matter input (in the field) or they quality of organic matter (in the lab). The size of the microbial community, however, decreased over time in both situations, the ratio of bacteria to fungi in the soil seemed to increase over time also.

In this work over 200 temperature proxy data sets have been analyzed to determine if periodic and or quasi-periodic patterns exist in the data sets. References to the journal articles where data are recorded are provided. Chapter 1 serves an introduction to the problem of temperature determination in providing information on how various proxy data sources are derived. Examples are given of the techniques followed in producing proxy data that predict temperature for each method used. In chapter 2 temperature proxy data spanning the last 4000 years, from 2,000 BCE to 2,000 CE, are analyzed to determine if overarching patterns exist in proxy data sets. An average of over 100 proxy data sets was used to produce Figure 4. An overview of the data shows that several “peaks” can be identified. The data were then subjected to analysis using a series of frequency modulated cosine waves. This analysis led to a function that can be expressed by equation 3. The literature was examined to determine what mathematical models had been published to fit the experimental proxy data for temperature. A number of attempts have been made to fit data from limited data sets with some degree of success. Some other papers have used a sinusoidal function to best fit the changes in the temperature. After consideration of many published papers and reviewing long time streams of proxy data that appeared to have sine wave patterns, a new model was proposed for trial. As the patterns observed showed “almost” repeating sine cycles, a frequency modulated sine wave was chosen to obtain a best fit function. Although other papers have used a sinusoidal function to best fit the changes in the temperature, the “best fit” was limited. Thus, it was decided that a frequency modulated sine wave may be a better model that would provide a more precise fit. This proved to be the case and the more than 240 temperature proxy data sets were analyzed using Equation 3. In chapter 3 the time span for the proxy data was extended to cover the period of time 12,000 BCE to 2000 CE. The data were then tested by using the equation above to search for periodic/quasi-periodic patterns. These results are summarized under select conditions of time periods. In chapter 4 the interval of time is extended over 1,000,000 years of time to test for long period “periodic” changes in global temperature. These results are provided for overall analysis. The function f(x) as described above was used to test for periodic/quasi-periodic changes in the data. Chapter 5 provides an analysis of temperature proxy data for an interval of time of 3,000,000 years to establish how global temperature has varied during the last three million years. Some long-term quasi-periodic patterns are identified. Chapter 6 provides a summation of the model proposed for global temperature that can be expected if similar trends continue over future years as have prevailed for the past few million years. Data sets that were used in this work are tabulated in the appendices of this paper.

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<p>Тема докторске дисертације је анализа екстремених температура ваздуха на подручју Војводине (северни део Србије), која се простире на површини од 21.506 km2. У анализи су коришћене временске серије са десет метеоролошких станица за временски период од 1951. до 2000. године. Укупно је анализирано осам параметара екстремних температура, и то: средње максималне и минималне, апсолутне максималне и минималне и дани са екстремним температурама (ледени, мразни, летњи и тропски). Истовремено, у истраживање су укључене и временске серије распона средњих максимума и минимума, као и распон средњих апсолутних максимума и минимума. Током рада анализирани су годишњи, сезонски и месечни низови претходно наведених параметара екстрема. У циљу добијања неопходних резултата, коришћено је више метода, као што су: Александерсонов тест, проста линеарна регресија, t-тест, Мен-Кендалов тест, коефицијент корелације, кластер анализа, анализа ројева тачака, хистограм и вишеструка линеарна регресија. Резултати хомогености месечних и сезонских временских серија, који су добијени коришћењем Александерсоновог теста, представљају прве резултате за простор Војводине и показују да је 26% испитиваних низова нехомогено, од којих је 11% подешено, односно хомогенизовано. Анализе параметара екстремних температура ваздуха показују тенденције пораста у последњих педесет година XX века. Посматрајући годишње низове, јављају се позитивни трендови код свих параметара (осим за ледене и мразне дане, где су трендови опадајући), међутим, једино се за средње минималне температуре може потврдити да имају сигнификантан пораст током испитиваног периода. Истовремено, зимски и пролећни трендови имају највишу тенденцију пораста, док су са друге стране јесењи трендови генерално опадајући. Анализом распона максималних и минималних температура, увидело се да максималне температуре генерално имају нешто већи пораст од минималних, а карактеристике оваквих флуктуација делимично су објашњене корелационом анализом са другим климатским елементима, који могу имати утицај на екстреме. Резултати су показали да високу корелациону повезаност (углавном преко 0,7), односно утицај на екстремне температуре имају инсолација, облачност, падавине и релативна влажност ваздуха. Интересантно је напоменути, да у већини радова који анализирају распоне максималних и минималних температура у појединим регионима, на нивоу континента или глобалном нивоу, указују на негативне трендове распона екстрема, међутим на простору Војводине годишњи распони имају благи позитиван тренд. Коришћењем вишеструке линеарне регресије, уочено је да показатељи атмосферске циркулације, односно NAO и AO индекси, објашњавају прилично висок проценат варијанси средњих и апсолутних максималних и минималних температура, током зимског, пролећног и летњег периода. Истовремено, узрок рапиднијег тренда пораста екстрема током последње декаде XX века, указује како на промене у осцилацијама других климатских елемената, тако и на промене доминације, односно учесталости појаве одређених типова атмосферске циркулације. Резултати у докторској дисертацији показују да деведесете године представљају најтоплију декаду на простору Војводине у оквиру испитиваног периода, што је највероватније повезано и са високим позитивним вредностима NAO индекса током исте декаде, које имају утицај на пораст зимских и пролећних вредности екстремних температура.</p> / <p>Tema doktorske disertacije je analiza ekstremenih temperatura vazduha na području Vojvodine (severni deo Srbije), koja se prostire na površini od 21.506 km2. U analizi su korišćene vremenske serije sa deset meteoroloških stanica za vremenski period od 1951. do 2000. godine. Ukupno je analizirano osam parametara ekstremnih temperatura, i to: srednje maksimalne i minimalne, apsolutne maksimalne i minimalne i dani sa ekstremnim temperaturama (ledeni, mrazni, letnji i tropski). Istovremeno, u istraživanje su uključene i vremenske serije raspona srednjih maksimuma i minimuma, kao i raspon srednjih apsolutnih maksimuma i minimuma. Tokom rada analizirani su godišnji, sezonski i mesečni nizovi prethodno navedenih parametara ekstrema. U cilju dobijanja neophodnih rezultata, korišćeno je više metoda, kao što su: Aleksandersonov test, prosta linearna regresija, t-test, Men-Kendalov test, koeficijent korelacije, klaster analiza, analiza rojeva tačaka, histogram i višestruka linearna regresija. Rezultati homogenosti mesečnih i sezonskih vremenskih serija, koji su dobijeni korišćenjem Aleksandersonovog testa, predstavljaju prve rezultate za prostor Vojvodine i pokazuju da je 26% ispitivanih nizova nehomogeno, od kojih je 11% podešeno, odnosno homogenizovano. Analize parametara ekstremnih temperatura vazduha pokazuju tendencije porasta u poslednjih pedeset godina XX veka. Posmatrajući godišnje nizove, javljaju se pozitivni trendovi kod svih parametara (osim za ledene i mrazne dane, gde su trendovi opadajući), međutim, jedino se za srednje minimalne temperature može potvrditi da imaju signifikantan porast tokom ispitivanog perioda. Istovremeno, zimski i prolećni trendovi imaju najvišu tendenciju porasta, dok su sa druge strane jesenji trendovi generalno opadajući. Analizom raspona maksimalnih i minimalnih temperatura, uvidelo se da maksimalne temperature generalno imaju nešto veći porast od minimalnih, a karakteristike ovakvih fluktuacija delimično su objašnjene korelacionom analizom sa drugim klimatskim elementima, koji mogu imati uticaj na ekstreme. Rezultati su pokazali da visoku korelacionu povezanost (uglavnom preko 0,7), odnosno uticaj na ekstremne temperature imaju insolacija, oblačnost, padavine i relativna vlažnost vazduha. Interesantno je napomenuti, da u većini radova koji analiziraju raspone maksimalnih i minimalnih temperatura u pojedinim regionima, na nivou kontinenta ili globalnom nivou, ukazuju na negativne trendove raspona ekstrema, međutim na prostoru Vojvodine godišnji rasponi imaju blagi pozitivan trend. Korišćenjem višestruke linearne regresije, uočeno je da pokazatelji atmosferske cirkulacije, odnosno NAO i AO indeksi, objašnjavaju prilično visok procenat varijansi srednjih i apsolutnih maksimalnih i minimalnih temperatura, tokom zimskog, prolećnog i letnjeg perioda. Istovremeno, uzrok rapidnijeg trenda porasta ekstrema tokom poslednje dekade XX veka, ukazuje kako na promene u oscilacijama drugih klimatskih elemenata, tako i na promene dominacije, odnosno učestalosti pojave određenih tipova atmosferske cirkulacije. Rezultati u doktorskoj disertaciji pokazuju da devedesete godine predstavljaju najtopliju dekadu na prostoru Vojvodine u okviru ispitivanog perioda, što je najverovatnije povezano i sa visokim pozitivnim vrednostima NAO indeksa tokom iste dekade, koje imaju uticaj na porast zimskih i prolećnih vrednosti ekstremnih temperatura.</p> / <p>This doctoral thesis deals with extreme air temperatures in Vojvodina (northern part of Serbia), which covers the area of 21,506 km2. Data series at ten meteorological stations for the period 1951- 2000 were used in the analysis. The following eight parameters of extreme temperatures were analysed: mean maximum and minimum; absolute maximum and minimum; and extreme temperature days (freezing, frosty, summer and tropical). Concurrently, the temporal series of mean maximum and minimum range were included into the research, as well as the range of mean absolute maximum and minimum. Annual, seasonal and monthly ranges of the aforementioned extreme parameters were included in the analysis. Towards obtaining important results, several methods were employed, such as Alexandersson test, simple linear regression, T-test, Mann-Kendall test, cluster analysis, scatterplot, histogram and multiple linear regressions. The results of homogenous monthly and seasonal temporal series obtained by employing Alexandersson test, being the first of the kind for Vojvodina highlighted that there were 26% non-homogenous, out of which 11% adjusted, i.e. homogenised within the analysed series. The analyses of extreme air temperature parameters trends showed increase in the last fifty years of the 20th century. Observation of annual series indicated positive trends for all parameters (except for freezing and frosty days, when the trends decreased). However, only mean minimal temperatures confirmed significant increase in the analysed period. Concurrently, winter and spring trends showed the highest increase, whereas autumn trend showed general decrease. In the course of the analysis of maximum and minimum temperature ranges, it was perceived that maximum temperatures generally showed higher increase compared to minimum, whereas the fluctuation features were partially explained by correlation analysis with other climatic elements, which might have influenced extremes. The results approved that high correlation coefficient (mainly above 0.7), i.e. the impact on extremes was perceived with insolation, cloudiness, precipitation and relative air humidity. Interestingly enough, most of the papers researching the series of maximum and minimum temperatures in certain regions, either continental or global, indicate negative trends in ranges of extremes. On the other hand, in Vojvodina the annual ranges show a moderately positive trend. The multiple linear regression technique brought to the perception that atmospheric circulation indicators, i.e. NAO and AO indices, explained the distinctly high percentage of variances in mean and absolute maximum and minimum temperatures during winter, spring and summer period. Concurrently, the cause of rapid increase in extremes during the 1990s indicated both the changes in oscillations of other climatic elements and changes in domination, i.e. frequency of certain types of atmospheric circulation. The results obtained for the doctoral dissertation indicated that the 1990s were the warmest decade in Vojvodina for the analysed period. Most probably, it was associated with high positive values of NAO index for the period, which affected winter and spring values of extreme temperatures.</p>

The diploma thesis contains an energy audit of the figure skating hall. In the first part I focused on the analysis of the topic, fire regulations and laws relating to given theme, recent technical, theoretical and experimental solutions in practice. In the next part, I compiled the of building energy audit of building, including its mandatory annexes. In the last part, I presented the results of measurements in the evaluated object.