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The anhysteretic remanent magnetization (ARM) is a laboratory-imparted artificial remanence that is used widely in mineral magnetic studies (Dunlop & Özdemir, 1997). An ARM is usually imparted by exposing a sample to an alternating field (AF; e.g., ∼100 mT) with a superimposed small direct current (DC; e.g., ∼50 μT) bias field. The bulk ARM is given as the sum of the ARM of each component (Egli, 2004a(Egli, , 2004bFabian & Leonhardt, 2009):where M ar is the bulk ARM imparted with a DC field H dc for a sample containing N magnetic components with saturation remanence M rs and component-specific ARM ratios, 𝐴𝐴 𝜘𝜘𝑖𝑖 = 𝜒𝜒𝑎𝑎𝑖𝑖∕𝑀𝑀𝑟𝑟𝑟𝑟𝑖𝑖 , where 𝐴𝐴 𝜘𝜘𝑖𝑖 is the ratio of the ARM

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Historically, China has experienced frequent barrier lake breach hazards, and several cases have been monitored during their occurrences using complete breach flood hydrographs. These have enabled the analysis of dam breaches to be improved by merging hydraulics and soil mechanics expertise. Some novel improvements to analytical methods have also been published. This study presents the authors' proposed hyperbolic soil erosion and lateral enlargement models, together with a numerical algorithm that enables easy calculation of the breach flood hydrograph. In general, the peak flows calculated using this improved method agree with field measurements and are less sensitive to input parameters. The research outcomes are presented on an Excel spreadsheet (DB‐IWHR, online download available), and these are self‐explanatory with minimal tutorials. This software will be of particular use in an emergency situation, when it is necessary to quickly evaluate the breach flood. This study reviews four large‐scale barrier lake breaches; the Yigong breach which documented a peak flow close to 100,000 m3/s and the recent Baige breaches featuring burst recurrences over a month‐long period. This article is categorized under: Science of Water> Water Extremes Engineering Water > Planning Water

Time series of the dryness-wetness (DW) index of 531 yr (AD 1470(AD -2000 at 42 stations in regions A (most of North China and the east of Northwest China) and B (the Yangtze-Huaihe River valley) in China are applied to investigating the historical DW characteristics over various periods of the series with a relatively stationary average value using Bernaola-Galvan (BG) algorithm. The results indicate that region A/B underwent three drought-intensive periods (DIP) in the last 531 years. In the DIP of the last 130 years, the frequency of DW transition has increased in region A, but not obviously changed in region B in comparison with the other two historical DIPs. The dry period started in about 1920 in region A with severe drought events occurring from the late 1970s to the early 1980s. It lasted for about 50-70 yr in this century, and then a DW shift took place. The wet period in region B might maintain for the coming several decades. The variations of DW in region A are positively correlated with changes in temperature, but in region B, the correlation with temperature is weaker. It is found that the number of DW indices of various categories within a running window is an exponential function of the running window length. The dryness scale factor (DSF) is defined as the reciprocal of the characteristic value of the exponential distribution, and it has a band-like fluctuation distribution that is good for the detection of extreme drought (flood) clustering events. The results show that frequencies of the severe large-scale drought events that concurrently occurred in regions A and B were high in the late 12th century, the early 13th century, the early 17th century, and the late 20th century. This provides evidence for the existence of the time-clustering phenomena of droughts (floods).

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Although continental shelves account for only approximately 7.5% of the ocean's surface, they are a globally important reservoir for terrigenous sediments (Saito et al., 1998). Therefore, sedimentary records from continental shelves are ideal for high-resolution studies on geological and environmental evolutions such as local tectonic subsidence, source-sink processes, and climate changes (e.g., Knies et al., 2003). In addition, as a transitional zone between the land and deep ocean, sedimentary architectures on the continental shelf, especially in low-gradient and broad continental margins, are controlled by a range of factors including variations in sea-level