Dynamical downscaling forecasts of Western North Pacific tropical cyclone genesis and landfall

This study evaluates the potential use of the regional climate model version 3 (RegCM3) driven by (1) the National Centers for Environmental Prediction (NCEP) Climate Forecast System Reanalysis (CFSR) data during 1982–2001 and (2) the NCEP Climate Forecast System Version 2 (CFS2) hindcast data during 2000–2010 in forecasting Western North Pacific (WNP) tropical cyclone (TC) activity. The first experiment is conducted to investigate the ability of the model in generating a good climatology of TC activity in spatial and temporal scales, so the model could be used in the second experiment to test its ability in forecasting TC genesis and landfall. Both experiments extend through the May to October WNP-TC season. Results show that the use of RegCM3 driven by the CFSR achieves a better simulation on the temporal and spatial variation of WNP-TC genesis during 1982–2001, as compared to previous studies using the same model but driven by the ERA40 reanalysis. In addition, diagnoses on the use of RegCM3 driven by the CFS2 point out that the 2000–2010 WNP-TC genesis locations and numbers from the model are very similar to those from the observations. The skill of RegCM3 in the forecasts of landfalling TCs is higher over the Southeast Asian region than over the other sub-regions of East Asia. Potential causes for such regional differences are discussed. Most importantly, statistical analyses show that the use of RegCM3 driven by the CFS2 gives a better forecast skill than the use of CFS2 alone for the prediction of WNP-TCs making landfall in East Asia. This indicates that the use of a dynamical downscaling method for the global forecast data would likely lead to a higher forecast skill of regional TC landfalls in most of the East Asian region.     

我国近海中度嗜盐菌的分离筛选及其产酶多样性分析

为了解我国近海中度嗜盐菌系统发育多样性及产酶特性,从天津、山东、江苏、福建、海南等地近海采集样品为研究对象,分离筛选得到108株中度嗜盐菌,其中有26株至少产一种酶。通过对其形态特征、生理生化、16SrRNA基因序列及系统进化树进行分析,将26株菌鉴定为细菌域的Halomonas、Idiomarina、Virgibacillus、Pontibacillus、Oceanobacillus、Halobacillus和Marinilactibacillus属的菌株。它们与相应属的模式菌株16SrRNA基因序列相似性在97%~100%不等,其中有些菌株可能代表不同的分类单元。底物特异性试验表明,分离的26株中度嗜盐菌13株产蛋白酶,19株产淀粉酶,13株产酯酶,4株产纤维素酶。其中6株产3种酶,11株产2种酶。研究结果表明中度嗜盐菌具有系统发育和产酶多样性,同时蕴藏着较多新的微生物类群,为嗜盐微生物资源应用开发提供了参考。     

Relationship between magnetic properties and heavy metals of urban soils with different soil types and environmental settings: implications for magnetic mapping

Two types of soil (fluvisols and anthrosols) were collected from different environmental settings (suburb and industrial area) in Wuhan, central China, aiming to examine the applicability of magnetic mapping for heavy metal pollution of urban soil in a large region. Magnetic measurements and chemical analysis indicated elevated magnetization and heavy metal concentrations of topsoils in the industrial area. Magnetic susceptibility (χ), anhysteretic remanent magnetization (ARM) and saturation isothermal remanent magnetization (SIRM) of fluvisols are much higher than those of anthrosols, but contrary for frequency-dependent susceptibility, indicating that soil magnetism strongly depends on the soil type/condition. Predominant magnetic carrier in topsoils in industrial area is pseudo-single-domain/multi-domain magnetite. Environmental scanning electron microscope/energy dispersive X-ray examination of the magnetic extracts from these topsoils revealed abundant spherical particles with diameters of 10–50 μm that are rich in iron-oxides, and could be attributed to the nearby industrial activities (e.g., steel work and power generation). Significant correlations were observed between magnetic concentration-related parameters (e.g., χ, ARM and SIRM) and concentrations of Cu, Pb, Zn, Hg and Tomlinson pollution load index. These results proposed that magnetic proxy mapping of soil pollution is an effective, fast and inexpensive tool for delineation of heavy metal pollution. However, interpretation of magnetic properties for such a purpose must be done on a site-specific basis, taking into account the possibilities of pedogenic enhancement/depletion under the specific soil conditions.     

Material characteristics and deterioration evaluation for the 13th century Korean stone pagoda of Magoksa temple

This study focused on the quantitative deterioration evaluation for the Magoksa temple stone pagoda of the thirteenth century in Korea, based on the deterioration map by precise observation and ultrasonic velocity measurements. The stone pagoda is composed mainly of fine-grained quartz diorite with some granodiorite used in the second story and dew bowl, and the replacement stone for restoration in the basement is biotite granite. The deterioration map and the 2D contour map projecting ultrasonic velocity showed that the most serious deterioration was to the north face of the pagoda, which has about 81.2% deterioration rate and a low velocity range compared with the other directions. Thus, it is required to prepare conservation schemes to reduce deterioration and reinforce the structure. It is also required to carry out ground exploitation for calculation of load carrying strength and ground strength together with continuous structural monitoring. The results will be important for the stable and long-term conservation of the pagoda and will further serve to establish scientific conservation systems of stone cultural heritages in the future.     

普里兹湾沉积物样品产油真菌筛选及胞内脂肪酸成分分析

对中国第29次南极科学考察获得的南极普里兹湾海域23个站位的深海沉积物样品进行了真菌分离培养,共获得了11个属的21株真菌,分别是:青霉属(Penicillium,9株)、枝孢属(Cladosporium,3株)、支顶孢属(Acremonium,1株)、短梗霉属(Aureobasidium,1株)、孢盘菌属(Botryotinia,1株)、散囊菌属(Eurotiales,1株)、外瓶霉属(Exophiala,1株)、镰孢菌属(Fusarium,1株)、丛赤壳属(Nectria,1株)、茎点霉属(Phoma,1株)、帚枝霉属(Sarocladium,1株).南极普里兹湾海域的真菌多样性较高,其中青霉属菌株最多,占总菌株比例为42.85%,是普里兹湾真菌中的优势属,其次为枝孢属菌株,占总菌株比例为14.29%.分别用尼罗红和氯化三苯基四氮唑(TTC)对这21株菌进行产油筛选,得到8株产油菌,分属于Penicillium(2株)、Aureobasidium(1株)、Cladosporium(1株)、Eurotiales(1株)、Exophiala(1株)、Fusarium(1株)、Sarocladium(1株)等7个属,这些产油菌产油量大致在20.1%到52.0%之间.对这8株菌的产油量和胞内脂肪酸成分进行分析,结果表明:这些产油菌所含的基本为短链脂肪酸,且不饱和脂肪酸含量较高,适合作为生物柴油的生产菌株.     

黄河源区鄂陵湖湖面和湖边草地对流边界层湍流结构特征的大涡模拟研究

为研究黄河源区边界层湍流特征及其对物质和能量输送的影响,本文首次采用大涡模拟的方法,对比分析了黄河源区两种不同下垫面上(鄂陵湖和湖边草地)对流边界层(CBL)中精细的湍流结构特征.使用资料为2012年夏季黄河源区鄂陵湖流域野外观测实验的GPS探空资料、涡动相关观测资料.分析表明,模拟的黄河源区草地和湖上CBL的平均结构...     

The Response of Anomalous Vertically Integrated Moisture Flux Patterns Related to Drought and Flood in Southern China to Sea Surface Temperature Anomaly

With the extreme drought (flood) event in southern China from July to August in 2022 (1999) as the research object, based on the comprehensive diagnosis and composite analysis on the anomalous drought and flood years from July to August in 1961-2022, it is found that there are significant differences in the characteristics of the vertically integrated moisture flux (VIMF) anomaly circulation pattern and the VIMF convergence (VIMFC) anomaly in southern China in drought and flood years, and the VIMFC, a physical quantity, can be regarded as an indicative physical factor for the "strong signal" of drought and flood in southern China. Specifically, in drought years, the VIMF anomaly in southern China is an anticyclonic circulation pattern and the divergence characteristics of the VIMFC are prominent, while those are opposite in flood years. Based on the SST anomaly in the typical draught year of 2022 in southern China and the SST deviation distribution characteristics of abnormal draught and flood years from 1961 to 2022, five SST high impact areas (i.e., the North Pacific Ocean, Northwest Pacific Ocean, Southwest Pacific Ocean, Indian Ocean, and East Pacific Ocean) are selected via the correlation analysis of VIMFC and the global SST in the preceding months (May and June) and in the study period (July and August) in 1961-2022, and their contributions to drought and flood in southern China are quantified. Our study reveals not only the persistent anomalous variation of SST in the Pacific and the Indian Ocean but also its impact on the pattern of moisture transport. Furthermore, it can be discovered from the positive and negative phase fitting of SST that the SST composite flow field in high impact areas can exhibit two types of anomalous moisture transport structures that are opposite to each other, namely an anticyclonic (cyclonic) circulation pattern anomaly in southern China and the coastal areas of east China. These two types of opposite anomalous moisture transport structures can not only drive the formation of drought (flood) in southern China but also exert its influence on the persistent development of the extreme weather.