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The impact of geological disasters on mountainous settlement have been focused on in recent years. Despite the booming development in the modeling of hazards and vulnerability, the risk assessment in mountainous area still have difficulty in absence of refined data. Moreover, development imbalances widely exist in mountainous areas, which were ignored in previous research. In this study, the refined distribution of socioeconomic data is obtained by using spatialization from the census, which eases the situation of the lack of data. Then, a frequency ratio-random forest model is conducted to evaluate the geological disasters hazards. Meanwhile, vulnerability was evaluated using triangular fuzzy number‑based analytic hierarchy process. In vulnerability assessment, the inhomogeneity index is integrated to evaluate the imbalance between indicators, the use of which can reward a more realistic vulnerability result. Finally, risk map was produced by multiplying hazard and vulnerability. The risk assessment framework is applied in Lushan and Baoxing counties of Southwestern China, which is a typical mountainous area with frequent earthquakes, uneven development, and a lack of high-precision data. The total area of high and extremely high hazards (868.82 km2), vulnerability (258.66 km2), and risk (113.49 km2) are estimated and mapped. The proposed risk assessment framework quantifies the impact of development inhomogeneity on risk and contributes to the scientific assessment of vulnerability for mountainous settlements. [ABSTRACT FROM AUTHOR]

Excavated glass artifacts are usually environmentally impacted, causing spatial inhomogeneity which poses great challenges for accurate and non-destructive chemical characterization. Here, we present our study on accurate characterization of archaeological glass with Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), a high-precision and minimally destructive analytic method. Using three corroded glass beads excavated from Guangnan, Yunnan, Southern China as examples, we discuss the issues that may be involved when observing signal curves of highly inhomogeneous archaeological glass, as well as provide chemical characterization for the intact pristine body. Results indicate that these Indo-Pacific monochrome beads are of the potassium silicate glass type and used mineral potash source, and that they contain copper as the colorant. By discussing the breadth and depth types of inhomogeneity and focusing on perturbation endured by major elements, we identify the extent of environmental alteration and describe how different elements and matrices can respond differently to the archaeological environment, leading to various corrosion behaviors. For such samples LA-ICP-MS is shown to be an advantageous tool to provide archaeologically relevant information, or to probe artifact conditions for conservation purposes. A good understanding of sample conditions, and close attention to the experimental and calibration process are required to overcome inhomogeneity when tackling archaeological glass. [ABSTRACT FROM AUTHOR]

Excavated glass artifacts are usually environmentally impacted, causing spatial inhomogeneity which poses great challenges for accurate and non-destructive chemical characterization. Here, we present our study on accurate characterization of archaeological glass with Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), a high-precision and minimally destructive analytic method. Using three corroded glass beads excavated from Guangnan, Yunnan, Southern China as examples, we discuss the issues that may be involved when observing signal curves of highly inhomogeneous archaeological glass, as well as provide chemical characterization for the intact pristine body. Results indicate that these Indo-Pacific monochrome beads are of the potassium silicate glass type and used mineral potash source, and that they contain copper as the colorant. By discussing the breadth and depth types of inhomogeneity and focusing on perturbation endured by major elements, we identify the extent of environmental alteration and describe how different elements and matrices can respond differently to the archaeological environment, leading to various corrosion behaviors. For such samples LA-ICP-MS is shown to be an advantageous tool to provide archaeologically relevant information, or to probe artifact conditions for conservation purposes. A good understanding of sample conditions, and close attention to the experimental and calibration process are required to overcome inhomogeneity when tackling archaeological glass. [ABSTRACT FROM AUTHOR]

A wavelet-analysis-based homogenization method (WHM) is developed for detecting and adjusting biases of variability in a daily climate observation series, which are influential in the estimation of climate extremes and relevant trends in the time series. WHM is applied to the Central England daily mean temperature series (CET, 1772-2010) and the daily mean temperature series at Henan station in mountainous western China (HNT, 1960-2008) in order to demonstrate the usefulness of the new technique. The changes of methods for calculating daily mean temperature for CET in 1878 caused significantly reduced daily variability (DV) in the subsequent sub-series of CET. The relocation of the Chinese station in 1981 to a higher mountainous site resulted in not only enhanced DV but also in weather (weekly) time-scale variability ( WV) in the subsequent sub-series of HNT. The adjustments based on WHM in the present cases improve the estimates of the long-term trends of climate extremes such as hot days, cold days, heat waves, and cold surges. A few widely applied methods of homogenization such as multiple analysis of series for homogenization ( MASH), higher-order moment (HOM), RHtestsV3 with quantile-matching (QM) adjustments and two-phase regression (TPR) are also applied to HNT for comparison. TPR is not aimed at improving the homogeneity of variability in the time series; MASH does not improve daily variability either; HOM improves it in a small way; and with RHtestsV3 with QM adjustments it is considerably improved, but biases remain. In contrast, WHM improves the homogeneity of the short-term variability in the time series, resulting in reasonable assessments of climate extremes and trends in the daily observations. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the results of an experimental study in which the occurrence and evolution of inhomogeneity in the strength of a uniform-originated silty seabed were investigated. The pore pressure and penetration strength at different depths inside the seabed were observed during the experimental process under the weight of the soil and under the action of waves of different heights (H=5cm, 10cm, 15cm). We found that a well-mixed silty seabed consolidates under the stress of its own weight, and its strength gradually increases as a result. Small wave action consolidates and strengthens the seabed and sediment. When the seabed is exposed to progressively higher waves, a fluidised response characterised by an arc-shaped boundary surface occurs on the seabed, and this response further controls the occurrence and evolution of the strength inhomogeneity of a uniform-origin seabed. The analyses clearly illustrate that features of seabed erosion and mass-transportation activity previously ascribed to increasing wave-current bed shear stress are controlled primarily by the process of wave-induced inhomogeneity in the strength of seabed sediments originating in the preceding period. In addition, the implications of the mechanism are explored. [Copyright &y& Elsevier]

We have used the China Homogenized Historic Temperature dataset and some long-term station series of the neighbor countries from CRUTEM3, a 5°×5° gridded dataset of monthly mean temperature since 1900, to provide a 107-year record of surface temperature trends and variability. We derived a comprehensive set of uncertainty estimates to accompany the data: measurement and sampling errors, uncertainties in temperature bias estimates, and uncertainties arising from limited observational coverage on large-scale averages have all been estimated. We reanalysed the temperature changes during the period of record. The best estimates of trends for 1900--2006 with uncertainties at 95% confidence range are about 0.09±0.017°C/decade for the year as a whole, and 0.14±0.021°C/decade, 0.11±0.021°C/decade, 0.04±0.017°C/decade, and 0.07±0.017°C/decade for winter, spring, summer and autumn respectively. For 1954--2006, the trends for annual, winter, spring, summer and autumn are: 0.26±0.032°C/decade, 0.35±0.046°C/decade, 0.25±0.051°C/decade, 0.16±0.037°C/decade and 0.22±0.055°C/decade. Winter saw the most significant warming trend in both 1900--2006 and 1954--2006, while during the most recent period (the satellite era, 1979--2006), all the seasons show similar warming trends: 0.45±0.13°C/decade, 0.51±0.11°C/decade, 0.52±0.16°C/decade, 0.37±0.10°C/decade and 0.50±0.16°C/decade for annual, winter, spring, summer and autumn. Trends arising from urbanization have been evaluated as less than 5% of the total warming trend for 1951--2001, so this bias was not removed. [ABSTRACT FROM AUTHOR]

The article discusses the effects of site change and urbanization on the 1977-2006 temperature series in Beijing (BJ), China. It provides an overview of the location change of the BJ meteorological station and mentions that the daily BJ temperature series was used to analyze how site-change and urbanization affects climate changes. Site-change-induced and urbanization-related warming biases were quantified. It concludes that BJ climatic warming in 1977-2006 is about 0.48 degrees Celsius/decade.