Add Fundamental Geospatial Data DEM to QGIS

Introduction

Terrain analysis and 3D mapping sometimes call for high-accuracy elevation data. A convenient source is the digital elevation model (DEM) in Fundamental Geospatial Data, provided by the Geospatial Information Authority of Japan (GSI). This DEM is high-quality elevation data that covers all of Japan, and it is free to use.

This article explains the steps for adding the Fundamental Geospatial Data DEM to QGIS.

What is Fundamental Geospatial Data?

Fundamental Geospatial Data is data published by GSI that collects the many kinds of data that serve as a foundation for analysis with map data. It includes roads, the locations and outlines of buildings, elevation, and geoid height, organized into three sets: “Basic Items,” “Digital Elevation Model,” and “Geoid Model.”

This article uses the DEM, one of the three sets. It divides Japan into mesh units (squares of a set size) or into regional units such as Hokkaido and Kanto, and contains the elevation of each area. The data is provided in XML format.

Download the Fundamental Geospatial Data DEM

How to use the Fundamental Geospatial Data Download Service

First, open the Fundamental Geospatial Data Download Service.

You need an account to download data from the service. Click the login button at the upper right, create an account, and log in. The official page has detailed instructions.

After you log in, scroll down the page and click the blue Digital Elevation Model (数値標高モデル) button.

A page for selecting the data you want to download opens.

The items on this screen are as follows.

1. You can select the area you need data for on the map.
2. You can search for the display area by address or coordinates.
3. You can narrow down the data to search.
4. Besides selecting data directly on the map, you can select it by municipality or regional division.

For other details, see the official GSI help page.

Download the DEM

This article uses the DEM5A data (5 m mesh airborne laser survey data) for the mesh that covers Chuo ward in Sapporo as an example to explain how to get the Fundamental Geospatial Data DEM.

1. In the left menu, under Search conditions (検索条件指定), check only 5A (Airborne Laser Survey) (5A（航空レーザー測量）).
2. In the left menu, under Selection method (選択方法指定), choose Select by municipality (市区町村単位で選択). In the drop-down menus, select Hokkaido (北海道) and Chuo ward, Sapporo (札幌市中央区), then click Add to search results list (検索結果リストに追加).
3. Review the search results list. For only the data you need, click Add (追加) on the right side of the table.
4. Click the Download list (ダウンロードリスト) tab in the table below the map.

5. Confirm that all the data you want to download is selected.
6. Click the Proceed to download (ダウンロード等へ) button.

A page listing the files you specified opens. Click Download (ダウンロード) on the right side of the page to start the download.

Add the DEM to QGIS

Install the plugin

QGIS cannot work with the data downloaded from the Fundamental Geospatial Data Download Service as it is.

Install the QGIS plugin QuickDEM4JP so that QGIS can work with the data. QuickDEM4JP is a QGIS plugin that converts the Fundamental Geospatial Data DEM into general-purpose formats: GeoTIFF or Terrain RGB.

You can install QuickDEM4JP from the Plugin Manager. Open Plugin Manager, search for QuickDEM4JP, and install the plugin that appears. For details on installing QGIS plugins with the Plugin Manager, see the “Search for and install a plugin” section of the article below.

Add data to QGIS with the plugin

Launch the QuickDEM4JP plugin you installed. Find the plugin icon in the toolbar and click it.

Next, use QuickDEM4JP to convert the Fundamental Geospatial Data elevation data into a file such as GeoTIFF.

1. Click the ... button next to the DEM file (.xml or .zip containing .xml) field, and specify the DEM file you downloaded from Fundamental Geospatial Data.
2. Choose at least one of Output DEM Geotiff and Output Terrain RGB, then click its ... button to specify the output location. Terrain RGB data needs further processing before QGIS can use it, so generate GeoTIFF if you want to use the DEM in QGIS.
3. Click Run at the lower right.

When the plugin finishes, QGIS adds the DEM.

Once the Fundamental Geospatial Data DEM is in QGIS, you can use it for terrain analysis, 3D map creation, creating elevation profiles, and many other purposes. The QuickDEM4JP plugin also makes it easy to convert the data to a general-purpose file format, so put it to use in your geospatial analysis work and research.

When you use the DEM, you must cite the source. For details, see “Source Attribution” on the GSI website. Depending on your purpose, you may also need to apply to GSI in addition to citing the source. You can check the specific procedures at “Map Use Procedure Navi” on the GSI website.

Conclusion

This article explained how to get the Fundamental Geospatial Data DEM, how to install the QGIS plugin QuickDEM4JP, and how to use the plugin to add the DEM to QGIS.

QuickDEM4JP, the QGIS plugin introduced in this article, is open-source software. To report a bug or suggest an improvement, create an issue on GitHub, or fix the code and submit a pull request.