No abstract

ABSTRACT:Rainfall records for 23 countries and territories in the western Pacific have been collated for the purpose of examining trends in total and extreme rainfall since 1951. For some countries this is the first time that their data have been included in this type of analysis and for others the number of stations examined is more than twice that available in the current literature. Station trends in annual total and extreme rainfall for 1961-2011 are spatially heterogeneous and largely not statistically significant. This differs with the results of earlier studies that show spatially coherent trends that tended to reverse in the vicinity of the South Pacific Convergence Zone (SPCZ). We infer that the difference is due to the Interdecadal Pacific Oscillation switching to a negative phase from about 1999, largely reversing earlier rainfall changes. Trend analyses for 1981-2011 show wetter conditions in the West Pacific Monsoon (WPM) region and southwest of the mean SPCZ position. In the tropical North Pacific it has become wetter west of 160 • E with the Intertropical Convergence Zone/WPM expanding northwards west of 140 • E. Northeast of the SPCZ and in the central tropical Pacific east of about 160 • E it has become drier. Our findings for the South Pacific subtropics are consistent with broader trends seen in parts of southern and eastern Australia towards reduced rainfall. The relationship between total and extreme rainfall and Pacific basin sea surface temperatures (SSTs) has been investigated with a focus on the influence of the El Niño-Southern Oscillation (ENSO). We substantiate a strong relationship between ENSO and total rainfall and establish similar relationships for the threshold extreme indices. The percentile-based and absolute extreme indices are influenced by ENSO to a lesser extent and in some cases the influence is marginal. Undoubtedly, larger-scale SST variability is not the only influence on these indices.

In order to recover sugar from the cellulosic material in refuse, the kinetics of the acid hydrolysis of Kraft paper slurries were determined. A sequential pseudo-first-order model: cellulose + sugar +. decomposed sugar developed by Saeman for hydrolysis of wood chips was found to fit the data. The kinetic parameters are evaluated up to 240°C for acid concentrations of 0 . 2 2 , 0.5%, and 1.0%. At 230°C with 1.0% acid, 5 2 x of the cellulose can be converted to sugar in 20 sec. The model was found to apply t o ground refuse which contained as little as 38 % cellulose. n trying to find new ways to cope with the disposal of

In this paper we report on the development of a new homogeneous dataset for Pacific Island station temperatures, and the variability and change that these data show. We have worked closely with meteorological services in the Pacific and East Timor to collate and rehabilitate historical climate records, incorporating homogeneity assessment and adjustment where appropriate to produce reliable analyses of temperature trends. Overall, these homogeneity adjustments create no systematic bias compared to the raw data since the early 1960s, but improve both spatial and temporal consistency at the individual station level for both variability and trends.The updated homogeneous records indicate that mean temperatures have increased at all available Pacific island stations over 1961-2010, with rates ranging from +0.04 to +0.33 ºC/decade, across the network as a whole. The strongest warming trends are found in Papua New Guinea and French Polynesia, while none of the homogeneous station records show cooling over the past 70, 50 or 30 years. Trends in maximum and minimum temperatures are very similar to those of mean temperature at most stations, apart from in Fiji, Tonga and Niue where there is a tendency for greater warming for maximum temperatures. The amount of warming in the wet and dry seasons is also similar at most stations, although stations in Fiji, Tonga and Niue display more warming during the wet season.A simple regional mean of Pacific island series shows a trend of +0.16 °C/decade over 1961-2010 and indicates that 2010 was the warmest year on record averaged across the stations available at time of analysis. This regional mean station series compares well with a regional mean series extracted from a global gridded dataset for the last 50 years. Overall, the warming in Pacific Island temperature records over the past half-century is consistent with that expected from humaninduced global warming and is large relative to natural interannual variability associated with factors such as the El Niño-Southern Oscillation. IntroductionInhabitants of small islands are amongst the most vulnerable to climate change, with long-term climate change posing threats to agriculture, water supplies, health, livelihoods and even the existence of small island countries (UNFCCC 2005, Mimura et al. 2007. It is therefore important to understand the range of climate variability experienced in the past to help identify potential adaptation options, as well as provide context for the interpretation of projected climate changes for the future.Recognising the vulnerability of smaller countries in the western Pacific to climate change, the Australian government established a program of climate research called the Pacific Climate Change Science Program (PCCSP 2 ) to meet highpriority science needs to support climate change adaptation 2 The PCCSP has subsequently moved under a new program of work called the Pacific-Australia Climate Change Science and Adaptation Planning Program. The majority of the work reported in this paper was fun...

No abstract