矢量格式的地理空间数据来源#

Sources of geospatial data in vector format

中文

基于矢量的地理空间数据将物理特征表示为点、线和多边形的集合。通常，这些特征将具有与之关联的元数据。在本节中，我们将介绍一些主要的免费矢量格式地理空间数据来源。

英文

Vector-based geospatial data represents physical features as collections of points, lines, and polygons. Often, these features will have metadata associated with them. In this section, we will look at some of the major sources of free vector-format geospatial data.

TIGER#

TIGER

中文

美国人口普查局提供了大量的地理空间数据，名为 TIGER（拓扑集成地理编码与参考系统） 。TIGER数据包括有关街道、铁路、河流、湖泊、地理边界以及法律和统计区域（如学区和城市区域）的信息。此外，还提供了单独的制图边界和人口统计文件以供下载。

下图显示了加利福尼亚州的州界和城市区域轮廓，这些数据是从TIGER网站下载的：

由于TIGER数据是由美国政府生产的，因此它仅包含美国及其保护区（如波多黎各、美属萨摩亚、北马里亚纳群岛、关岛和美属维尔京群岛）的信息。对于这些地区，TIGER是一个非常优秀的地理空间数据源。

英文

The United States Census Bureau have made available a large amount of geospatial data under the name TIGER (Topologically Integrated Geographic Encoding and Referencing System). The TIGER data includes information on streets, railways, rivers, lakes, geographic boundaries, and legal and statistical areas such as school districts, and urban regions. Separate cartographic boundary and demographic files are also available for download.

The following screenshot shows state and urban area outlines for California, based on data downloaded from the TIGER website:

Because it is produced by the US government, TIGER only includes information for the United States and its protectorates (Puerto Rico, American Samoa, the Northern Mariana Islands, Guam, and the US Virgin Islands). For these areas, TIGER is an excellent source of geospatial data.

数据格式#

Data format

中文

直到2006年，美国人口普查局提供的TIGER数据是以一种名为TIGER/Line的自定义文本格式提供的。TIGER/Line文件将每种类型的记录存储在单独的文件中，并且需要使用自定义工具进行处理。幸运的是，OGR支持TIGER/Line文件，如果需要读取这些文件，您可以使用它。

自2007年以来，所有TIGER数据都以shapefile格式提供，这些shapefile文件被称为TIGER/Line shapefiles（有些令人困惑）。

您可以下载包含街道地址范围、地标、普查块、大都市统计区和学区等地理空间数据的最新shapefile。例如，“核心统计区”（Core Based Statistical Area）shapefile包含了每个统计区的轮廓：

该特征具有以下相关元数据：

ALAND 2606489666.0
AWATER 578526971.0
CBSAFP 18860
CSAFP None
FUNCSTAT S
INTPTLAT +41.7499033
INTPTLON -123.9809983
LSAD M2
MEMI 2
MTFCC G3110
NAME Crescent City, CA
NAMELSAD Crescent City, CA Micropolitan Statistical Area
PARTFLG N

有关这些属性的详细信息可以在TIGER网站的详细文档中找到。

您还可以下载包含人口、房屋数量、中位年龄和种族分布等人口统计数据的shapefile。例如，以下地图根据加利福尼亚州各大都市区的总人口对其进行了着色：

英文

Up until 2006, the US Census Bureau provided the TIGER data in a custom text-based format called TIGER/Line. TIGER/Line files stored each type of record in a separate file, and required custom tools to process. Fortunately, OGR supports TIGER/Line files should you need to read them.

Since 2007, all TIGER data has been produced in the form of shapefiles, which are (somewhat confusingly) called TIGER/Line shapefiles.

You can download up-to-date shapefiles containing geospatial data such as street address ranges, landmarks, census blocks, metropolitan statistical areas, and school districts. For example, the “Core Based Statistical Area” shapefile contains the outline of each statistical area:

This particular feature has the following metadata associated with it:

ALAND 2606489666.0
AWATER 578526971.0
CBSAFP 18860
CSAFP None
FUNCSTAT S
INTPTLAT +41.7499033
INTPTLON -123.9809983
LSAD M2
MEMI 2
MTFCC G3110
NAME Crescent City, CA
NAMELSAD Crescent City, CA Micropolitan Statistical Area
PARTFLG N

Information on these various attributes can be found in the extensive documentation available at the TIGER website.

You can also download shapefiles which include demographic data such as population, number of houses, median age, and racial breakdown. For example, the following map tints each metropolitan area in California according to its total population:

获取和使用 TIGER 数据#

Obtaining and using TIGER data

中文

TIGER数据文件可以从以下链接下载：

http://www.census.gov/geo/www/tiger/index.html

确保下载技术文档，因为它描述了您可以下载的各种文件，以及与每个要素相关的所有属性。例如，如果您想下载当前的美国城市区数据，您需要查找的shapefile名为tl_2012_us_uac10.shp，其中包含城市或镇的名称以及其面积（以平方米为单位）等信息。

英文

The TIGER datafiles can be downloaded from:

http://www.census.gov/geo/www/tiger/index.html

Make sure that you download the technical documentation, as it describes the various files you can download, and all of the attributes associated with each feature. For example, if you want to download a current set of urban areas for the US, the shapefile you are looking for is called tl_2012_us_uac10.shp and it includes information such as the city or town name and the size in square meters.

Natural Earth#

Natural Earth

中文

Natural Earth (http://www.naturalearthdata.com) 是一个提供公共领域矢量和栅格地图数据的免费网站，提供高分辨率、中等分辨率和低分辨率的地图数据。提供两种类型的矢量地图数据：

文化地图数据：包括国家、省州、城市区和公园轮廓的多边形数据，以及人口密集地区、道路和铁路的点线数据：

自然地图数据：包括陆地、海岸线、海洋、岛屿、珊瑚礁、河流、湖泊等的多边形和线字符串数据：

所有这些数据都可以免费下载并在您的地理空间程序中使用，使得Natural Earth网站成为您应用程序的优秀数据来源。

英文

Natural Earth (http://www.naturalearthdata.com) is a website that provides public domain vector and raster map data at high, medium, and low resolutions. Two types of vector map data are provided:

Cultural map data: This includes polygons for country, state or province, urban area, and park outlines, as well as point and line data for populated places, roads, and railways:

Physical map data: This includes polygons and linestrings for land masses, coastlines, oceans, minor islands, reefs, rivers, lakes, and so on:

All of this can be downloaded and used freely in your geospatial programs, making the Natural Earth site an excellent source of data for your application.

数据格式#

Data format

中文

Natural Earth 网站上的所有矢量格式数据都以 shapefile 形式提供。所有数据均使用地理坐标（纬度和经度），并采用标准的 WGS84 坐标系，这使得在您的应用程序中使用这些文件非常方便。

英文

All the vector-format data on the Natural Earth website is provided in the form of shapefiles. All the data is in geographic (latitude and longitude) coordinates, using the standard WGS84 datum, making it very easy to use these files in your own application.

获取和使用自然地球矢量数据#

Obtaining and using Natural Earth vector data

中文

Natural Earth 网站整体非常出色，下载所需文件也非常简单；只需点击主页上的 Get the Data 链接。然后，您可以选择分辨率和所需的数据类型，并选择下载单个 shapefile 或多个 shpaefile 文件打包下载。下载完成后，您可以使用上一章讨论的 Python 库来处理这些 shapefile 的内容。

Natural Earth 网站非常全面；它提供了有关可下载的地理空间数据的详细信息，还设有一个论坛，您可以在其中提出问题并讨论遇到的任何问题。

英文

The Natural Earth site is uniformly excellent, and downloading the files you want is easy; simply click on the Get the Data link on the main page. You can then choose the resolution and the type of data you are looking for, and you can choose to download either a single shapefile, or a number of shapefiles bundled together. Once they are downloaded, you can use the Python libraries discussed in the previous chapter to work with the contents of these shapefiles.

The Natural Earth website is very comprehensive; it includes detailed information about the geospatial data you can download, and a forum where you can ask questions and discuss any problems you may have.

全球、自洽、分层、高分辨率海岸线数据库 (GSHHS)#

Global, self-consistent, hierarchical, high-resolution shoreline database (GSHHS)

中文

美国国家地球物理数据中心（隶属于 NOAA）一直致力于制作全球范围的高质量矢量海岸线数据。该项目的成果 称为全球自一致性、分层高分辨率海岸线数据库（GSHHS），该数据库包含了五种不同分辨率的海岸线、湖泊和河流的详细矢量数据。数据被划分为四个不同的“级别”：海洋边界、湖泊边界、岛屿内湖泊边界和岛屿上的池塘边界。

以下截图显示了从 GSHHS 数据库中提取的欧洲海岸线、湖泊和岛屿：

GSHHS 是由两个公共领域的地理空间数据库构建而成：世界数据银行 II 包含海岸线、湖泊和河流的数据，而世界矢量海岸线仅提供海岸线数据。由于世界矢量海岸线数据库的数据更为精确，但缺少关于河流和湖泊的信息，因此这两个数据库被结合起来，提供尽可能准确的信息。合并数据库后，作者手动编辑了数据，以确保一致性并消除许多错误。最终结果是一个高质量的全球陆地和水体边界数据库。

备注

有关创建 GSHHS 数据库过程中所使用方法的更多信息，请访问：http://www.soest.hawaii.edu/pwessel/papers/1996/JGR_96/jgr_96.html

英文

The US National Geophysical Data Center (part of the NOAA) have been working on a project to produce high-quality vector shoreline data for the entire world. The resulting database, called the Global self-consistent, hierarchical, high-resolution shoreline database (GSHHS), includes detailed vector data for shorelines, lakes, and rivers at five different resolutions. The data has been broken out into four different “levels”: ocean boundaries, lake boundaries, island-in-lake boundaries, and pond-on-island-in-lake boundaries.

The following screenshot shows European shorelines, lakes, and islands, taken from the GSHHS database:

The GSHHS has been constructed out of two public-domain geospatial databases: the World Data Bank II includes data on coastlines, lakes, and rivers, while the World Vector Shoreline only provides coastline data. Because the World Vector Shoreline database has more accurate data, but lacks information on rivers and lakes, the two databases were combined to provide the most accurate information possible. After merging the databases, the author then manually edited the data to make it consistent and to remove a number of errors. The result is a high-quality database of land and water boundaries worldwide.

备注

More information about the process used to create the GSHHS database can be found at: http://www.soest.hawaii.edu/pwessel/papers/1996/JGR_96/jgr_96.html

数据格式#

Data format

中文

GSHHS 数据库有两种不同的格式可供选择：一种是专门为通用制图工具（Generic Mapping Tools，http://gmt.soest.hawaii.edu）设计的二进制数据格式，另一种是由一系列 shapefile 组成。

备注

通用制图工具（GMT） 是一套用于处理地理空间数据的工具。由于它没有 Python 绑定，因此在本书中我们不会使用 GMT。

如果你下载的是 shapefile 格式的数据，最终会得到 20 个独立的 shapefile，每个 shapefile 代表不同分辨率和级别的组合：

分辨率表示地图细节的程度：

分辨率代码	分辨率	包含内容
c	粗略	大于 500 平方公里的特征
l	低	大于 100 平方公里的特征
i	中等	大于 20 平方公里的特征
h	高	大于 1 平方公里的特征
f	完整	每个特征

级别表示 shapefile 中包含的边界类型：

级别代码	包含内容
1	海洋边界
2	湖泊边界
3	岛屿内湖泊边界
4	岛屿上的池塘边界

shapefile 的名称会告诉你所包含数据的分辨率和级别。例如，表示海洋边界的完整分辨率 shapefile 将命名为 GSHHS_f_L1.shp。

每个 shapefile 包含一个单独的图层，图层中包括组成给定边界类型的各种多边形特征。

英文

The GSHHS database is available in two different formats: a binary data format specific to the Generic Mapping Tools (http://gmt.soest.hawaii.edu), and as a series of shapefiles.

备注

Generic Mapping Tools (GMT) is a collection of tools for working with geospatial data. Because they don’t have Python bindings, we won’t be working with GMT in this book.

If you download the data in shapefile format, you will end up with a total of twenty separate shapefiles, one for every combination of resolution and level:

The resolution represents the amount of detail in the map:

Resolution Code	Resolution	Includes
c	Crude	Features greater than 500 sq.km.
l	Low	Features greater than 100 sq.km.
i	Intermediate	Features greater than 20 sq.km.
h	High	Features greater than 1 sq.km.
f	Full	Every feature

The level indicates the type of boundaries that are included in the shapefile:

Level Code	Includes
1	Ocean boundaries
2	Lake boundaries
3	Island-in-lake boundaries
4	Pond-on-island-in-lake boundaries

The name of the shapefile tells you the resolution and level of the included data. For example, the shapefile for ocean boundaries at full resolution would be named GSHHS_f_L1.shp.

Each shapefile consists of a single layer containing the various polygon features making up the given type of boundary.

获取 GSHHS 数据库#

Obtaining the GSHHS database

中文

GSHHS 的主网站可以在以下地址找到：

http://www.ngdc.noaa.gov/mgg/shorelines/gshhs.html

这些文件同时提供了 GMT 和 shapefile 格式——除非你特别想使用通用制图工具（Generic Mapping Tools），否则你最可能选择下载 shapefile 版本。一旦下载了数据，你可以使用 OGR 以常规方式读取这些文件并提取数据。

英文

The main GSHHS website can be found at:

http://www.ngdc.noaa.gov/mgg/shorelines/gshhs.html

The files are available in both GMT and shapefile format—unless you particularly want to use the Generic Mapping Tools, you will most likely want to download the shapefile version. Once you have downloaded the data, you can use OGR to read the files and extract the data from them in the usual way.

世界边界数据集#

World Borders Dataset

中文

到目前为止，我们所研究的许多数据源都相当复杂。如果您只需要一些简单的矢量数据，覆盖整个世界，那么“世界边界数据集”可能就足够了。虽然某些国家边界存在争议，但世界边界数据集的简洁性使其成为许多基本地理空间应用的一个有吸引力的选择。

以下地图就是使用世界边界数据集生成的：

本书将在多个章节中广泛使用世界边界数据集。实际上，您已经在《第3章，Python地理空间开发库》中看到过一个示例程序，我们使用Mapnik和世界边界数据集的Shapefile生成了世界地图。

英文

Many of the data sources we have examined so far are rather complex. If all you are looking for is some simple vector data covering the entire world, the World Borders Dataset may be all you need. While some of the country borders are apparently disputed, the simplicity of the World Borders Dataset makes it an attractive choice for many basic geospatial applications.

The following map was generated using the World Borders Dataset:

The World Borders Dataset will be used extensively throughout this book. Indeed, you have already seen an example program in Chapter 3, Python Libraries for Geospatial Development, where we used Mapnik to generate a world map using the World Borders Dataset shapefile.

数据格式#

Data format

中文

世界边界数据集以一个 shapefile 的形式提供，包含一个图层，每个国家对应一个要素。对于每个国家，该要素包含一个或多个多边形，定义了国家的边界，以及有用的属性，包括国家或地区的名称、各种 ISO、FIPS 和联合国代码，用于标识国家、区域和子区域分类、国家的人口、土地面积以及经纬度。

这些不同的代码使得将要素与您自己特定国家的数据匹配变得容易，您还可以使用人口和面积等信息在地图上突出显示不同的国家。例如，上述截图使用 “region” 字段，使用不同的颜色绘制每个地理区域。

英文

The World Borders Dataset is available in the form of a shapefile with a single layer and one feature for each country. For each country, the feature has one or more polygons that define the country’s boundary, along with useful attributes including the name of the country or area, various ISO, FIPS, and UN codes identifying the country, a region and subregion classification, the country’s population, land area, and latitude/longitude.

The various codes make it easy to match the features against your own country- specific data, and you can also use information such as the population and area to highlight different countries on the map. For example, the preceding screenshot uses the “region” field to draw each geographic region using a different color.

获取世界边界数据集#

Obtaining World Borders Dataset

中文

世界边界数据集可以从以下网址下载：

http://thematicmapping.org/downloads/world_borders.php

该网站还提供了有关数据集内容的进一步详细信息，包括指向联合国网站的链接，联合国网站上列出了区域和子区域代码。

英文

The World Borders Dataset can be downloaded from:

http://thematicmapping.org/downloads/world_borders.php

This website also provides further details on the contents of the dataset, including links to the United Nations’ website where the region and subregion codes are listed.

矢量格式的地理空间数据来源#

OpenStreetMap#

数据格式#

获取和使用 OpenStreetMap 数据#

OpenStreetMap API#

Planet.osm#

镜像站点和摘录#

使用 OpenStreetMap 数据#

TIGER#

数据格式#

获取和使用 TIGER 数据#

Natural Earth#

数据格式#

获取和使用自然地球矢量数据#

全球、自洽、分层、高分辨率海岸线数据库 (GSHHS)#

数据格式#

获取 GSHHS 数据库#

世界边界数据集#

数据格式#

获取世界边界数据集#