GHSL: Global Human Settlement Layers, Settlement Grid 1975-1990-2000-2014 (P2016)
The GHSL relies on the design and implementation of new spatial data mining technologies allowing to automatically process and extract analytics and knowledge from large amount of heterogeneous data including: global, fine-scale satellite image data streams, census data, and crowd sources or volunteered geographic information sources.
The GHS-SMOD is the rural-urban Settlement classification MODel adopted by the GHSL. It is the representation of the degree of urbanization (DEGURBA) concept into the GHSL data scenario. Each grid in the GHS-SMOD has been generated by integrating the GHSL built-up areas and GHSL population grids data for reference epochs: 1975, 1990, 2000, 2015.
The DEGURBA classification schema is a people-based definition of cities and settlements: it operates using as main input a 1 km² grid cell accounting for population at a given point in time. The DEGURBA discriminates the population grid cells in three main classes: 'urban centers' (cities), 'urban clusters' (towns and suburbs), and 'rural grid cells'. (base). These class abstractions translate to 'high density clusters (HDC)', 'low density clusters (LDC)', and 'rural grid cells (RUR)', respectively, in the GHS-SMOD implementation.
The 'HDC' differ from the DEGURBA 'urban centers' in that they account for the over-fragmentation of cities in regions with large low-density residential development by integrating the built-up layer. In the GHS-SMOD representation, the 'HDC' are the spatial generalization of contiguous population grid cells (4-connectivity, gap-filling) with a density of at least 1500 inhabitants per km² or a density of built-up surface > 50%, and a minimum total resident population of 50000. The 'LDC' are continuous grid cells with a density of at least 300 inhabitants per km² and a minimum total population of 5000. The 'RUR' are grid cells outside 'HDC' and 'LDC' with population > 0 and < 300. Everything else is classified as inhabited areas where population = 0.
This dataset was produced in the World Mollweide projection (EPSG:54009).
For more information visit: Global Human Settlement - GHS SETTLEMENT GRID - European Commission.
The Global Human Settlement Layer (GHSL) project is supported by the European Commission, Joint Research Center, and Directorate-General for Regional and Urban Policy. The GHSL produces new global spatial information, evidence-based analytics, and knowledge describing the human presence in the planet.
GHSL依赖于新的空间数据挖掘技术的设计和实施，允许从大量的异质数据中自动处理和提取分析结果和知识，这些数据包括：全球的、精细的卫星图像数据流、人口普查数据以及人群来源或自愿的地理信息来源。
GHS-MOD是GHSL采用的农村-城市住区分类MODel。它是城市化程度（DEGURBA）概念在GHSL数据场景中的体现。GHS-MOD中的每个网格都是通过整合GHSL建成区和GHSL人口网格数据生成的，参考年代为：1975年、1990年、2000年、2015年。
DEGURBA分类模式是一个基于人的城市和住区的定义：它使用1平方公里的网格单元作为主要输入，说明在特定时间点的人口。DEGURBA将人口网格单元区分为三个主要类别："城市中心"（城市）、"城市群"（城镇和郊区）和 "农村网格单元"。(基地）。) 这些类别的抽象在GHS-MOD的实现中分别转化为 "高密度集群（HDC）"、"低密度集群（LDC）"和 "农村网格单元（RUR）"。
HDC "与DEGURBA的 "城市中心 "不同，它通过整合建筑层，考虑了在有大量低密度住宅发展的地区，城市过度分散的问题。在GHS-MOD中，"HDC "是连续的人口网格单元的空间概括，其密度至少为每平方公里1500人，或建成区面积密度大于50%，常住人口总数至少为50000。LDC "是连续的网格单元，密度为每平方公里至少300人，总人口至少为5000人。RUR "是 "HDC "和 "LDC "之外的网格单元，人口>0且<300。其他都被归类为人口=0的居住区。
这个数据集是以世界莫尔维德投影法（EPSG:54009）制作的。
欲了解更多信息，请访问：http://ghsl.jrc.ec.europa.eu/ghs_smod.php。
全球人类住区层（GHSL）项目由欧盟委员会、联合研究中心和区域与城市政策总局支持。GHSL产生新的全球空间信息、基于证据的分析和描述人类在地球上存在的知识。
Dataset Availability
1975-01-01T00:00:00 - 2015-12-31T00:00:00
Dataset Provider
EC JRC
Collection Snippet
ee.ImageCollection("JRC/GHSL/P2016/SMOD_POP_GLOBE_V1")
Resolution
1000 meters
Bands Table
Name | Description |
|---|---|
smod_code | Degree of urbanization |
Class Table: smod_code
Value | Color | Color Value | Description |
|---|---|---|---|
0 | #000000 | Inhabited areas | |
1 | #448564 | RUR (rural grid cells) | |
2 | #70daa4 | LDC (low density clusters) | |
3 | #ffffff | HDC (high density clusters) |
数据说明：
The GHSL has been produced by the EC JRC as open and free data. Reuse is authorised, provided the source is acknowledged. For more information, please read the use conditions (European Commission Reuse and Copyright Notice).
引用:
Pesaresi, Martino; Freire, Sergio (2016): GHS Settlement grid following the REGIO model 2014 in application to GHSL Landsat and CIESIN GPW v4-multitemporal (1975-1990-2000-2015). European Commission, Joint Research Centre (JRC) [Dataset] PID: Joint Research Centre Data Catalogue - GHS-SMOD R2016A - GHS settlement grid, following t... - European Commission
代码：
代码语言：javascript复制var dataset = ee.ImageCollection('JRC/GHSL/P2016/SMOD_POP_GLOBE_V1')
.filter(ee.Filter.date('2015-01-01', '2015-12-31'));
var degreeOfUrbanization = dataset.select('smod_code');
var visParams = {
min: 0.0,
max: 3.0,
palette: ['000000', '448564', '70daa4', 'ffffff'],
};
Map.setCenter(114.96, 31.13, 4);
Map.addLayer(degreeOfUrbanization, visParams, 'Degree of Urbanization');
