A relational database of global U-Pb ages

Enhanced understanding of how sampling techniques affect estimates of the global U-Pb age-distribution have, in turn, constrained U-Pb database design. Recent studies indicate that each continent has a unique age-distribution, as determined by zircon ages dated by the U-Pb isotope method. Likewise, broad regions within a continent also exhibit diverse age-distributions. To achieve a reliable estimate of the global distribution, the heterogenous composition of the continental crust requires sampling as many regions as feasibly possible. To attain this goal, and to provide a method for calculating age histograms, the records from a recent global U-Pb compilation are supplemented with 281,631 new records. These additions increase the database size to 700,598 records. In addition, the data are now restructured and made available as a relational database. After filtering the records by the six age-models included with the database, the results reveal two problems that might generally be unrecognized. First, an abrupt switch in the best-age at any given point(such as 1000 Ma) from ^(206)Pb/^(238)U ages to ^(207)Pb/^(206)Pb ages artificially depresses the age-distribution at the cutoff point. Second, rejecting analyses based on either absolute discordance or the magnitude of 2σ precision errors artificially depresses the age-distribution between 900 Ma and 2000 Ma. The results indicate that, when estimating the global U-Pb age-distribution, the methods for determining best-age and for rejecting records both require some attention. Possible solutions include using either an Accuracy Model or a Precision Model for estimating best-age, and then including all U-Pb records in the estimate, rather than rejecting any of them.

Global Pharmacopoeia Genome Database is an integrated and mineable genomic database for traditional medicines derived from eight international pharmacopoeias

Genomic data have demonstrated considerable traction in accelerating contemporary studies in traditional medicine. However,the lack of a uniform format and dispersed storage limits the full potential of herb genomic data. In this study, we developed a Global Pharmacopoeia Genome Database(GPGD). The database contains 34,346 records for 903 herb species from eight global pharmacopoeias(Brazilian, Egyptian, European, Indian, Japanese, Korean, the Pharmacopoeia of the People’s Republic of China, and U.S. Pharmacopoeia’s Herbal Medicines Compendium). In particular, the GPGD contains 21,872 DNA barcodes from 867 species, 2,203 organelle genomes from 674 species, 55 whole genomes from 49 species, 534 genomic sequencing datasets from 366 species, and 9,682 transcriptome datasets from 350 species. Among the organelle genomes, 534 genomes from 366 species were newly generated in this study. Whole genomes, organelle genomes, genomic fragments, transcriptomes, and DNA barcodes were uniformly formatted and arranged by species. The GPGD is publicly accessible at http://www.gpgenome.com and serves as an essential resource for species identification, decomposition of biosynthetic pathways, and molecular-assisted breeding analysis. Thus, the database is an invaluable resource for future studies on herbal medicine safety, drug discovery, and the protection and rational use of herbal resources.

The global climate monitor system:from climate data-handling to knowledge dissemination

This paper summarizes our work on building a data model and a geovisualization tool that provides access to global climate data:the Global Climate Monitor Web Viewer.Linked to this viewer,a complete set of climate-environmental indicators capable of displaying climate patterns on a global scale that is accessible to any potential user(scientists and laypeople)will be built and published using the same online application.The data currently available correspond to the CRU TS3.21 version of the Climate Research Unit(University of East Anglia)database–a product that provides data at a spatial resolution of half of a degree in latitude and longitude,spanning January 1901 to December 2012,on a monthly basis.Since January 2013,the datasets feeding the system have been the GHCN-CAMS temperature dataset and the Global Precipitation Climatology Centre(GPCC)First Guess precipitation dataset.Climatologists,hydrologists,planners and non-experts users such as media workers,policymakers,non-profit organizations,teachers or students,can access useful climatological information through the Global Climate Monitor system.

基于GDELT新闻大数据的东南亚地缘交互关系制图研究

地缘关系研究是地理学中的一个重要研究领域,基于大数据的地缘关系的定量研究是对传统定性地缘关系研究的必要补充。利用全球事件、语言与语调(global database of events,language,and tone,GDELT)新闻数据库获取中国与缅甸、老挝、越南、泰国和柬埔寨5个国家之间的交互事件,通过定量统计和空间制图、构建交互网络、时空热点分析等方法,对中国与这5个国家的地缘关系进行剖析。并以中缅为例分析两国地缘关系变化的原因,提出相应合作建议。结果表明,事件主要发生在各国政治经济文化较为活跃的地区;中国与越南和泰国的地缘交互较多,与越南的关系最为复杂;中国与五国的交互热点主要分布于越南、泰国、柬埔寨,除越南外,中国与另外4个国家的合作水平呈增强态势。

Interannual variability and climatic sensitivity of global wildfire activity

Understanding historical wildfire variations and their environmental driving mechanisms is key to predicting and mitigating wildfires. However, current knowledge of climatic responses and regional contributions to the interannual variability (IAV) of global burned area remains limited. Using recent satellite-derived wildfire products and simulations from version v1.0 of the land component of the U.S. Department of Energy's Energy Exascale Earth System Model (E3SM land model [ELM] v1) driven by three different climate forcings, we investigated the burned area IAV and its climatic sensitivity globally and across nine biomes from 1997 to 2018. We found that 1) the ELM simulations generally agreed with the satellite observations in terms of the burned area IAV magnitudes, regional contributions, and covariations with climate factors, confirming the robustness of the ELM to the usage of different climate forcing sources;2) tropical savannas, tropical forests, and semi-arid grasslands near deserts were primary contributors to the global burned area IAV, collectively accounting for 71.7%–99.7% of the global wildfire IAV estimated by both the satellite observations and ELM simulations;3) precipitation was a major fire suppressing factor and dominated the global and regional burned area IAVs, and temperature and shortwave solar radiation were mostly positively related with burned area IAVs;and 4) noticeable local discrepancies between the ELM and remote-sensing results occurred in semi-arid grasslands, croplands, boreal forests, and wetlands, likely caused by uncertainties in the current ELM fire scheme and the imperfectly derived satellite observations. Our findings revealed the spatiotemporal diversity of wildfire variations, regional contributions and climatic responses, and provided new metrics for wildfire modeling, facilitating the wildfire prediction and management.

Towards an index of all known species:the Catalogue of Life,its rationale,design and use

The Catalogue of Life,created by Species 2000 and the Integrated Taxonomic Information System,has the ambitious aim of creating a uniform and validated index of the world’s known species for use as a practical tool in inventorying and monitoring biodiversity worldwide.This is achieved by accessing an array of taxonomic databases created and made available by individual,project and institutional custodians through taxonomic and biodiversity initiatives.A standard data set is delivered for every known species,drawn from Species 2000 contributing databases.Data are provided to the Species 2000 Philippine office,compiled annually and published in CD-ROM format.Species 2000 also includes the Species Locator Service,which gives a responsible opinion as to the actual species currently recognized by taxonomists and their accepted names,and the Name Service that assists users in checking the spelling and original publication details for a wider range of names,including species not yet incorporated in the Species Locator Service.The Species Locator Service is available as the Dynamic Checklist,which is used to search for the scientific name of an organism online,and the Annual Checklist,which is a stable index produced once a year and is available on CD-ROM and online.Catalogue of Life currently covers more than 272000 species and 32000 infraspecies,with 181000 synonyms.It has 217000 common names,87000 references and 20 contributing databases that encompass all known animals,plants,fungi and microorganisms.