Terrain data is basic data that we often use in various designs and research! We have previously shared DEM terrain data with a precision of 12.5 meters and DEM terrain data with a precision of 30 meters (see previous articles for details).
What we bring to you this time is 90-meter resolution DEM terrain data - STRM 90m elevation data! The data was measured jointly by NASA and the National Mapping Agency (NIMA) of the Department of Defense. The original data provided by the official website is global data, divided into more than 1,000 grids. We downloaded the grid covering China and spliced it into one picture; then extracted the nationwide data according to the national boundaries, extracted the data of each province in the country according to the provincial boundaries, and extracted the data of each city in the country according to the city boundaries. It is convenient for everyone to use!
If you want nationwide data, please follow the forwarding requirements at the end of the article to obtain it! The following is a detailed introduction to the data:
01 Data Preview
Nationwide data
First, let’s take a look at the nationwide data. We will provide two types of data:
①Tif format data with a spatial range greater than China’s national boundaries
Since the original data divided the country into more than 1,000 grids, we spliced the networks involving China regions, so the scope is larger than China's national borders:
②The spatial range is equal to the tif format data of China’s national boundary
To cut the data that is larger than the national boundary formed by the above splicing grid, we use the administrative division data obtained from the Shudu City Official Account to extract nationwide data strictly according to the national boundary:
For each province, we will provide two major documents:
①Province-wide terrain
Let's take Shandong Province as an example to preview. We also cut the terrain based on the boundaries of Shandong Province, forming a terrain that is consistent with the boundaries of Shandong Province!
②Topography of cities in the province
Let’s take Shandong Province as an example. In addition to providing the province-wide terrain, we also provide the terrain of each of the 16 prefecture-level cities in Shandong Province. Let’s take Weifang City as an example:
02 Data details
Data introduction:
SRTM (Shuttle Radar Topography Mission), measured jointly by NASA and the National Mapping Agency (NIMA). On February 11, 2000, the "Endeavor" aircraft launched by the United States was equipped with an SRTM system. It conducted a total of 222 hours and 23 minutes of data collection, and obtained a total area of more than 119 million square kilometers between 60 degrees north latitude and 60 degrees south latitude. Radar image data covers more than 80% of the earth’s land surface. The amount of radar image data acquired by the SRTM system is approximately 9.8 trillion bytes. After more than two years of data processing, a digital terrain elevation model (DEM) was produced, which is now the SRTM terrain product data. This data product has been publicly released since 2003 and has undergone many revisions. The current data revision is version V4.1. SRTM terrain data can be divided into SRTM1 and SRTM3 according to accuracy, and the corresponding resolution accuracy is 30-meter and 90-meter data respectively (the data shared this time is 90-meter resolution data).
Geographic coordinate system:
GCS_WGS_1984
Data Format:
.tif format
Spatial resolution:
90m
Official download link:
http://srtm.csi.cgiar.org/srtmdata/
At the bottom of the article is our public account business card. We will regularly introduce various types of urban data as well as data visualization and analysis technology. Regarding STRM 90-meter resolution DEM terrain data, you are welcome to pay more attention to us to learn more!