A high quality, historical surface air temperature data set is essential for the reliable investigation of climate change and variability. In this study, such a data set has been prepared for Australia by adjusting raw mean annual temperature data for inhomogeneities associated with station relocations, changes in exposure, and other problems. Temperature records from long-term stations were collaborated from the set of all raw data held by the Australian Bureau of Meteorology. These long-term records were extended by combining stations and manually entering previously unused archived temperature measurements. An objective procedure was developed to determine the necessary adjustments, in conjunction with complementary statistical methods and station history documentation. The objective procedure involved creating a reference time series for each long-term station, from the median values at surrounding, well-correlated stations. Time series of annual mean maximum and mean minimum temperatures have been produced for 224 stations, and the adjusted dataset has been made available to the research community. The adjusted data are likely to be more representative of real climatic variations than raw data due to the removal of discontinuities. The adjusted data set has been compared with previously used temperature data sets, and data sets of other parameters. The adjusted data set provides adequate spatial coverage of Australia back to 1910. Additional adjusted data are available prior to this date at many stations. Trends in annual mean maximum, minimum, the mean of the maximum and minimum, and the range between the maximum and minimum, have been calculated at each site. Maximum and minimum temperatures have increased since about 1950, with minimum temperatures increasing faster than maximum temperatures.

No description available.

Thesis (M. Sc.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on Dec. 2, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Earth and Atmospheric Science, University of Alberta." Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 236-248).

Thesis (Ph. D.)--University of Oklahoma, 1998. / Includes bibliographical references (leaves 215-221).

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 90-103).

abstract / Earth Sciences / Doctoral / Doctor of Philosophy

This thesis examines whether short term (one to three weeks) microbial sensitivity to temperature and carbon (C) inputs can be predicted from peat characteristics driven by nutrient gradients. The aim was to determine if relationships exist between peat macronutrient (C, nitrogen (N), phosphorus (P)) concentrations, microbial community composition and the microbial response to changes in temperature and C supply. The focus of this thesis was on using peat macronutrient concentrations as explanatory variables as this is a metric which is easy to define and measure consistently, unlike other factors such as peat C quality and availability of nutrients. It was observed that, over short timescales, microbial respiration rates in peat soils increased in response to warming, nutrient (N and P) additions and increased labile C supply. In the first two experimental chapters it was found that peat respiration was sensitive to temperature, with increases of 10°C shown to increase microbial CO2 production by factors of 2.8 to 4.4. In the final two experimental chapters priming effects in peat were examined with C additions found to stimulate microbial activity and increases in peat derived CO2 flux, which could be attributed to priming. Despite the wide variation in nutrient concentrations in the peat soils examined no clear relationships between peat nutrient properties (total and available concentrations) and the magnitude of the microbial responses were observed.

This project studies the relation between the amount of sediment deposited in the Nile Submarine Cone (NSC) and the influence exerted by external controls such as climate change. A detailed calculation of sediment volumes was performed as well as a detailed estimation between intervals in order to assess sedimentation rates and dry mass per Ma for the NSC from the Late Oligocene to Recent. In contrast to previous studies, this project presents for the first time detailed calculations for ten intervals from Late Oligocene to Re- cent, including calculations for Pre-Messinian deposits since they also play an important role in the evolution of the NSC and in the history of erosion and deposition processes in the Nile province. The results of this project evidenced a connection between climate change and the amount of sediment carried by rivers as well as its final fate. Sedimenta- tion rate values obtained for each interval showed an increase in sediment supply during the Late Pliocene-Early Pleistocene, coincident with the i) final uplift of the Ethiopian and Somalian plateaus, ii) the drop in temperatures that took in the northern hemisphere as a consequence of the growth of the ice sheets, and iii) the increase in rainfall in the Ethiopian Highlands as a consequence of the African and Indian Monsoon that produced sapropel deposits and eroded sediments in north-eastern Africa. Pre-Messinian intervals showed low sedimentation rates values compared to Post-Messinian associated probably with an elevated evapo-transpiration cycle reducing the rainfall in the Ethiopian Highlands, des- pite the humid conditions that were present during certain ages (e.g. Zeit Wet Phase Late Miocene).