Volunteered Geographic Information: A Bicycling Enthusiast Perspective     

《制图学和地理信息科学》2013,40(3):258-268

Mapping technologies have made considerable strides in recent decades. Global positioning systems (GPS), remote sensing satellites, Web-based mapping services, and geographic information systems (GIS) have facilitated the collection, distribution, analysis, and ultimately interaction with geospatial information. In particular, portable GPS have altered how individuals participate in mapping. Individuals can use GPS to collect tracings of their personal interactions with the environment. These interactions can then be uploaded to one of many available Web-based mapping services. Once uploaded, the geospatial data can be mapped and shared among the broader community of users. Such volunteered geographic information (VGI) exemplifies the conceptualization of an individual collecting, mapping, and sharing personal geographic information. This paper focuses on challenges surrounding VGI. To help place these challenges in a broader context, specialized Web services and GPS technologies developed for the bicycling community will serve as examples of the current status and future prospects of VGI.  相似文献   

GTSPP资料在BCC海洋资料同化系统中的同化效果分析          下载免费PDF全文

武丰民  张祖强  肖贤俊  何金海  刘怀明 《大气科学学报》2014,37(1):38-46

介绍了国家气候中心第二代海洋资料同化系统(BCC_GODAS2.0)所用的模式和同化方案,并设计了两个试验对同化系统的效果和稳定性进行检验:一个是加入GTSPP资料的1990—2008年19 a的同化试验,另一个是同时段内不加任何资料的模拟试验。利用OISST和SODA(Simple Ocean Data Assimilation)数据集对试验结果进行评估。评估结果表明,加入GTSPP资料的同化结果可以有效改进原模式对温度和盐度的模拟。在表层,整个海洋的温度和盐度场误差都有所减小,其中热带太平洋的改进效果最为明显;此外,同化结果能更好地反映Nino3和Nino4区海表温度的时间演变。垂直层次上的修正效果也很明显,在200 m左右的混合层效果改进最好,温度的均方根误差可减小1.5℃,盐度的均方根误差可减小0.6 psu。  相似文献   

Performance of Regional Integrated Environment Modeling System (RIEMS) in the Simulation of Surface Air Temperature over East Asia   总被引：1，自引：0，他引：1       下载免费PDF全文

ZHAO De-Ming 《大气和海洋科学快报》2012,5(2):145-150

Regional climate models (RCMs) have the potential for more detailed surface characteristic and mesoscale modeling results than general circulation models (GCMs).These advantages have drawn significant focus on RCM development in East Asia.The Regional Integrated Environment Modeling System,version 2.0 (RIEMS2.0),has been developed from an earlier RCM,RIEMS1.0,by the Key Laboratory of Regional ClimateEnvironment for Temperate East Asia (RCE-TEA) and Nanjing University.A numerical experiment covering 1979 to 2008 (simulation duration from 1 January 1978 to 31 December 2008) with a 50-km spatial resolution was performed to test the ability of RIEMS2.0 to simulate long-term climate and climate changes in East Asia and to provide a basis for further development and applications.The simulated surface air temperature (SAT) was compared with observed meteorological data.The results show that RIEMS2.0 simulation reproduced the SAT spatial distribution in East Asia but that it was underestimated.The simulated 30-year averaged SAT was approximately 2.0°C lower than the observed SAT.The annual and interannual variations in the averaged SAT and their anomalies were both well reproduced in the model.A further analysis of three sub-regions representing different longitudinal ranges showed that there is a good correlation and consistency between the simulated results and the observed data.The annual variations,interannual variations for the averaged SAT,and the anomalies in the three sub-regions were also captured well by the model.In summary,RIEMS2.0 shows stability and does well both in simulating the long-term SAT in East Asia and in expressing sub-regional characteristics.  相似文献   

Conservation and development 2.0: Intensifications and disjunctures in the politics of online ‘do-good’ platforms     

《Geoforum》2017

An increasing amount of interactive ‘2.0’ crowdsourcing platforms raise awareness and funds for conservation and development projects worldwide. By enabling two-way online collaboration and communication, these ‘conservation and development 2.0’ platforms hoped to provide new impetus and popular legitimacy for conservation and development initiatives in the face of budget cuts and general criticism of the ‘formal’ aid sector after the financial crisis. This paper presents the case of the flagship ‘elephant corridor’ project on the Dutch pifworld.com platform to investigate whether and how the ‘2.0’ element has changed conservation and development in line with these expectations. The paper describes and analyses online and offline dynamics of the project and shows that while online excitement about the project remained high, the concomitant conservation and development promises and imaginations ill related to offline local realities. This rather ‘traditional’ conservation and development disjuncture, however, needs to be understood against the system peculiarities of the politics of online ‘do-good’ 2.0 platforms. The paper concludes that as these peculiarities are significantly intensifying and changing conservation and development dynamics, they do not elude familiar (1.0) disjunctures and might even obscure these further from sight.  相似文献   

Influence of offshore topography on the amplification of infragravity oscillations within a harbor     

《Applied Ocean Research》2017

The main purpose of this article is to systematically investigate the influence of offshore fringing reef topography on the infragravity-period harbor oscillations. The infragravity (IG) period oscillations inside an elongated harbor induced by normally-incident bichromatic wave groups are simulated using a fully nonlinear Boussinesq model, FUNWAVE 2.0. Based on an IG wave decomposition method, effects of plane reef-face slopes, reef-face profile shapes and the existence of reef ridge on bound and free IG waves and their relative components inside the harbor are comprehensively studied. For the given harbor and reef ridge, the range of the reef-face slopes and the various profile shapes studied in this paper, results show that the amplitude of the free IG waves inside the harbor increases with the increasing of the reef-face slope; while the bound IG waves inside the harbor seem insensitive to it. The effects of the profile shapes on the IG period waves inside the harbor are closely related to the width of the reef face. The existence of the reef ridge can relieve the bound IG waves to some extent when the incident short wave amplitudes are relatively large, while its effects on the free IG waves are negligible.  相似文献   

Simulated effects of cropland expansion on seasonal temperatures over China     

《Physics and Chemistry of the Earth》2015

Human activities result in deforestation, expansion of cropland, grassland degradation, urbanization and other large-scale land use/cover change; among these, cropland expansion is one of the most important processes. To understand the effects of cropland expansion on seasonal temperatures over China, two 21-year simulations (spanning January 1, 1980–December 31, 2000), using the Regional Integrated Environmental Model System (RIEMS 2.0), were performed. The two simulations comprised current realistic land use/cover patterns and the previous vegetation cover without crop expansion, to investigate the impact of crop expansion on seasonal temperatures over China. The results showed that due to cropland expansion: (1) the most obvious changes occurred in the maximum temperatures, followed by the mean surface air temperatures, and the minimum temperatures were the least affected; (2) the summer mean maximum temperatures decreased in most parts of eastern China, and the temperatures changed significantly in most parts of northeast China, north China and central China (p < 0.05); (3) the surface air temperatures, maximum temperatures and minimum temperatures in summer decreased in the different regions by between −0.03 and −0.76 °C (the greatest temperature changes occurred in southwest China, and the smallest were in northeast China); (4) the net radiation flux and latent heat flux increased, while the sensible flux decreased, when semi-desert vegetation was replaced by dry land crops, in both summer and winter seasons, and the converse occurred when irrigated crops were replaced by dry land crops. In addition, the net radiation flux and sensible heat flux decreased, and the latent heat flux increased when short grass and tall grass were replaced dry land crops, as well as when dry land crops were replaced by irrigated crops.  相似文献   

Modeling erosion and sediment control practices with RUSLE 2.0: a management approach for natural gas well sites in Denton County,TX, USA     

David J. Wachal  Kenneth E. Banks  Paul F. Hudak  R. Daren Harmel 《Environmental Geology》2009,56(8):1615-1627

Sediment yields from natural gas well sites in Denton County, TX, USA can be substantial and warrant consideration of appropriate erosion and sediment control best management practices (BMPs). Version 2 of the revised universal soil loss equation (RUSLE 2.0) was used to predict sediment yields and evaluate the efficiency of BMPs for multiple combinations of different land surface conditions (soil erodibility and slope) commonly found at gas well sites in the area. Annual average sediment yield predictions from unprotected site conditions ranged from 12.1 to 134.5 tonnes per hectare per year (t/ha/yr). Sediment yield predictions for 1, 2, 5, and 10-year design storms ranged from 8.1 to 20.6 t/ha. When site conditions were modeled with BMPs, predicted sediment yields were 52–93% less. A comparison of modeled efficiency values to a review of laboratory and field data suggests that modeled (theoretical) sediment yield results with BMPs are likely best case scenarios. This study also evaluated BMPs in the context of site management goals and implementation cost, demonstrating a practical approach for the application of RUSLE 2.0 for managing soil loss and understanding the importance of selecting appropriate site-specific BMPs for disturbed site conditions.  相似文献   

The astrometric observations of planetary satellites, close approaches and occultations of stars by asteroids and mutual events in the systems of planetary satellites with the 26-in. refractor of Pulkovo observatory in 1995-2006     

T.P. Kiseleva  I.S. Izmailov  A.A. Kiselev  E.V. Khrutskaya  M.Yu. Khovritchev 《Planetary and Space Science》2008,56(14):1908-1912

Astrometric and photometric observations of major planets, their satellites and asteroids have been made with the 26-in. refractor of the Pulkovo observatory during the period from 1995 to 2006. The CCD (ST6) and photographic observations were carried out. Accurate relative position of satellites of Jupiter and Saturn have been derived. The positions of Saturn have been calculated using the theoretically predicted coordinates of satellites relative to the planet without measurements of the photographic images of the planet. Also the observations of Hale-Bopp comet and Mercury transit have been made. The 26-in. refractor has been included into the international campaign PHEMU-2003: photometric CCD observations of mutual occultations and eclipses of Galilean satellites. The light curves of the events have been obtained and parameters of the events have been determined.  相似文献   

基于GeoWeb2.0的村镇民俗旅游电子商务设计与实现     

刘晓旭  胡卓玮  喻孟良  赵文吉  张鸣之 《测绘软科学研究》2010,(3):29-34

构建村镇民俗旅游电子商务、实现民俗旅游的信息化、网络化是促进民俗文化的传播与民俗旅游市场发展的有效手段。本文分析了村镇民俗旅游的特点,采用旅游电子商务模式,以Web Service技术为基础,结合Web2.0技术、WebGIS技术与多媒体技术,构建了基于GeoWeb2.0的村镇民俗旅游电子商务平台,实现以旅游目的空间信息为纽带的多媒体信息Mashup展示。为村镇管理部门、旅游从业者提供一个旅游资源信息管理与交流的整合平台,为解决民俗旅游经营中遇到的交流推广问题进行了尝试。  相似文献   

CAS-ESM2.0 Model Datasets for the CMIP6 Flux-Anomaly-Forced Model Intercomparison Project(FAFMIP)   总被引：3，自引：3，他引：0  

Jiangbo JIN  He ZHANG  Xiao DONG  Hailong LIU  Minghua ZHANG  Xin GAO  Juanxiong HE  Zhaoyang CHAI  Qingcun ZENG  Guangqing ZHOU  Zhaohui LIN  Yi YU  Pengfei LIN  Ruxu LIAN  Yongqiang YU  Mirong SONG  Dongling ZHANG 《大气科学进展》2021,38(2):296-306

The second version of the Chinese Academy of Sciences Earth System Model(CAS-ESM2.0)is participating in the Flux-Anomaly-Forced Model Intercomparison Project(FAFMIP)experiments in phase 6 of the Coupled Model Intercomparison Project(CMIP6).The purpose of FAFMIP is to understand and reduce the uncertainty of ocean climate changes in response to increased CO2 forcing in atmosphere-ocean general circulation models(AOGCMs),including the simulations of ocean heat content(OHC)change,ocean circulation change,and sea level rise due to thermal expansion.FAFMIP experiments(including faf-heat,faf-stress,faf-water,faf-all,faf-passiveheat,faf-heat-NA50pct and faf-heat-NA0pct)have been conducted.All of the experiments were integrated over a 70-year period and the corresponding data have been uploaded to the Earth System Grid Federation data server for CMIP6 users to download.This paper describes the experimental design and model datasets and evaluates the preliminary results of CAS-ESM2.0 simulations of ocean climate changes in the FAFMIP experiments.The simulations of the changes in global ocean temperature,Atlantic Meridional Overturning Circulation(AMOC),OHC,and dynamic sea level(DSL),are all reasonably reproduced.  相似文献