Color map design for visualization in flood risk assessment

Visualizations of flood maps from simulation models are widely used for assessing the likelihood of flood hazards in spatial planning. The choice of a suitable type of visualization as well as efficient color maps is critical to avoid errors or bias when interpreting the data. Based on a review of previous flood uncertainty visualization techniques, this paper identifies areas of improvements and suggests criteria for the design of a task-specific color scale in flood map visualization. We contribute a novel color map design for visualizing probabilities and uncertainties from flood simulation ensembles. A user study encompassing 83 participants was carried out to evaluate the effects of this new color map on user’s decisions in a spatial planning task. We found that the type of visualization makes a difference when it comes to identification of non-hazardous sites in the flood risk map and when accepting risks in more uncertain areas. In comparison with two other existing visualization techniques, we observed that the new design was superior both in terms of task compliance and efficiency. In regions with uncertain flood statuses, users were biased toward accepting less risky locations with our new color map design.     

Measurements of the vertical correlation in turbulence under broken waves

Turbulence measurements have been carried out in the surf zone of a wave flume. The purpose of the measurements is to determine the length scale of the turbulence generated by the wave breaking. The length scale of the turbulence is estimated on basis of the correlation between simultaneous measurements of the vertical turbulent fluctuations, taken at different levels above the bed.     

不同时间尺度、季节的气温数据空间平稳特征及其对插值结果的影响

不同时间尺度、季节的气温数据表现出不同的空间平稳特征。为探讨分析空间平稳性对气温插值的影响规律,采用趋势线法对气温数据进行空间平稳性探索,并对比分析不同空间平稳性条件下,普通线性回归、普通克里格、回归克里格的气温插值精度及插值结果的空间分布特点。结果显示：冬季日均、月均气温与年均气温呈现空间非平稳,插值精度随时间序列的增长而提高,随着气温数据逐渐趋于稳定,精度提高的幅度逐渐下降;夏季日均、月均气温呈现空间平稳,随时间序列的增长,插值精度的提高并不显著;夏季日均气温各插值方法的插值精度普遍高于冬季日均气温。与普通克里格相比,回归克里格能有效提高空间非平稳数据的插值精度。时间序列的增长削弱了不同插值算法之间的插值精度差异和插值结果空间分布差异。     

中亚地震目录震级转换及其完整性分析

为编制能够应用于地震危险性分析的中亚地区统一震级标度为矩震级的地震目录,从国际地震中心（ISC）下载得到该地区1907-2012年的地震数据,该数据包含众多机构不同震级标度的地震记录.以MW,GCMT为参考机构震级标度,并用最小二乘法拟合了其他机构震级标度与MW,GCMT之间的转换关系.在挑选某次地震事件的唯一震级记录时,以对应转换关系的相关系数大且剩余标准差小为准则进行筛选.对于少量没有震级转换关系或者拟合优度过差的地震记录,使用间接转换关系或者全球转换关系予以补充转换.震级转换后,用时空窗法删除前余震,并考虑构造环境和地震活动水平的空间差异性将研究区划分成5个子区域.采用地震记录时间累积曲线法、最大曲率法（MAXC）和拟合优度检验法（GFT）综合分析各个分区的最小完整震级（MC）,并在此基础上用极大似然法拟合相应的地震活动性参数.结果表明,每种完整性分析方法各具一定的优缺点,但采用综合分析的方法能够得出最佳的MC.地震记录时间累积曲线法能分析出高质量地震目录的起始时间,以作为后两种方法的基础,但容易受到地震活动水平随时间波动的影响.由于研究区目录质量较差,最大曲率法误差过大以至于只能作为其他方法的补充,拟合优度检验法的GFT参数也普遍只能达到80％左右.GFT最大值点可能并不对应MC,但是MC通常都在GFT极大值点取得.5个分区1964-2012年的MC普遍在Mw4.8左右,b值在1.136-1.514之间波动.     

基于TRMM卫星雷达降雨的流域陆面水文过程

利用热带降雨观测计划(TRMM)卫星雷达降雨数据驱动分布式陆面水文模型,研究流域尺度陆面水文过程,评估该数据在水文模拟与预报等研究领域的性能。通过与实测雨量资料比较,验证TRMM卫星雷达降雨数据的质量。分别将TRMM卫星雷达降雨与观测降雨作为耦合模型的气象输入,模拟和研究淮河流域1998~2003年的陆面水文过程时空变化。结果表明,TRMM卫星雷达降雨数据能够很好地描述降雨的时空分布,利用TRMM降雨模拟的结果与利用观测降雨模拟的结果精度相当;模拟流量与实测资料基本吻合。卫星雷达降雨数据在陆面水文过程研究中具有广泛的应用前景。     

Breeding,settlement and survival of barnacles at artificially modified shore levels at Leigh,New Zealand

The breeding and settlement seasons of the intertidal barnacles Chamaesipho brunnea, C. columna and Elminius plicatus were determined, and experiments using cages on the shore to examine barnacle survival and growth rate at four levels were carried out at Leigh during 1964–66.

Chamaesipho brunnea bred in spring and summer; C. columna and E. plicatus bred throughout the year, but settled intermittently. When protected from predators and from overgrowth by algae, all three species survived at levels lower than normal. At higher levels C. columna, E. modestus, Balanus trigonus and Tetraclita purpuraseens survived for significant periods (C. brunnea occurs naturally higher on the shore than the highest experimental level).     

A Queer Country? A case study of the politics of gay/lesbian belonging in an Australian country town

The present paper examines the complex politics of gay/lesbian belonging through a case study of Daylesford, Victoria, an Australian country town. It contributes to two research bodies: gay/lesbian rural geographies and the politics of belonging. Daylesford hosts ChillOut, Australia's largest rural gay/lesbian festival, which provides a telling context for investigating gay/lesbian belonging in rural Australia. We use qualitative data from the 2006 ChillOut Festival, including interviews with local residents, newspaper commentaries, and visitors’ surveys, to explore how Daylesford has been constructed, imagined, and experienced as a ‘unique’ site of gay/lesbian belonging in rural Australia. We find that ChillOut crucially contributes to its wider reputation as a gay-friendly country town, but also, we argue, to the contested nature of gay/lesbian belonging. This was most powerfully demonstrated by the local council's refusal to fly the gay-identified rainbow flag on the Town Hall during the 2006 Festival and its subsequent banning of the display of all festival flags from that key public building. Because ChillOut was the catalyst for this protocol, the resolution was viewed as homophobic. Indeed, the homophobic and heterosexist rhetoric that ensued in the Letters to the Editor section of the local newspaper revealed some residents’ underlying antagonism towards ChillOut and the local gay/lesbian community. Moreover, appealing to a shared ‘Australian identity’ and associated normative ‘family values’, these letter writers deployed a multi-scalar politics of belonging, where a sense of gay/lesbian belonging to Daylesford at the local scale was contested by the assertion of a ‘more meaningful’ national scale of allegiance fashioned by heteronormativity.     

Millennial-centennial scales climate changes of Holocene indicated by magnetic susceptibility of high-resolution section in Salawusu River valley,China

The upmost segment(Holocene series)of the Milanggouwan stratigraphic section(MGS1)in the Salawusu River valley shows 11 sedimentary cycles of dune sands and fluvio-lacustrine facies,or dune sands and paleosols.The analysis of the magnetic susceptibility of this segment suggests that there are 11 magnetic susceptibility cycles with the value alternating from low to high,in which the layers of the dune sands correspond to the lower value of the magnetic susceptibility and the layers of fluvio-lacustrine facies and paleosols correspond to the higher peaks.The study reveals that the low and high magnetic susceptibility values indicate the climate dominated by cold-arid winter monsoon and warm-humid summer monsoon of East Asia,respectively,and the study area has experienced at least 22 times of mil-lennial-centennial scales climate alternation from the cold-arid to the warm-humid during the Holocene.In terms of the time and the climate nature,the variations basically correspond to those of the North Atlantic and some records of cold-warm changes in China as well.They might be caused by the alternation of winter and summer monsoons in the Mu Us Desert induced by global climate fluctuations in the Holocene.     

Mixed Land Use and Obesity: An Empirical Comparison of Alternative Land Use Measures and Geographic Scales

Obesity is a growing epidemic in the United States. Walkable neighborhoods, characterized as having the three Ds of walkability (population Density, land use Diversity, and pedestrian-friendly Design), have been identified as a potentially promising factor to prevent obesity for residents. Past studies examining the relationship between obesity and walkability vary in geographic scales of neighborhood definitions and methods of measuring the three Ds. To better understand potential influences of these sometimes arbitrary choices, we test how four types of alternative measures of land use diversity measured at three geographic scales relate to body mass index for 4,960 Salt Lake County adults. Generalized estimation equation models demonstrate that optimal diversity measures differed by gender and geographic scale and that integrating walkability measures at different scales improved the overall performance of models.     

Reducing the non-axisymmetry of a planetary dynamo and an application to saturn

Abstract

If a conducting fluid shell is undergoing spin-axisymmetric differential rotation and overlies the dynamo generating region of a planet then it is capable of greatly reducing the non-spin-axisymmetric components of the generated field, provided the appropriate magnetic Reynolds number is large. The model, closely related to the electromagnetic skin effect, is quantified and applied to Saturn. The observed small dipole tilt (～ 1°) of Saturn's magnetic field can be explained because of the presence of a stably stratified conducting layer overlying the dynamo region. This layer is a predicted consequence of the thermal evolution, arises because of the limited solubility of helium in metallic hydrogen (Stevenson, 1980), and appears to be required by the Voyager infrared observations indicating depletion of helium from Saturn's atmosphere. The much larger dipole tilt angles of Jupiter and the Earth indicate the absence of any such stable, differentially rotating layer with a large magnetic Reynolds number.