ALOS Global Digital Surface Model "ALOS World 3D - 30m (AW3D30)"

AW3D30 Version 2.1

Thumbnails of AW3D30 DSM Ver.1.1 (As of March 2017. Black areas: masked out due to cloud cover)
  • Black color means no-data area due to masked out by cloud/snow cover.
  • Please click the map to zoom in/out in another browser.

1. Introduction

The Japan Aerospace Exploration Agency (JAXA) released "ALOS World 3D – 30m (AW3D30)", the global digital surface model (DSM) dataset with a horizontal resolution of approx. 30-meter mesh (1×1 arcsecond), free of charge in May 2015. Any of the commercial and non-commercial purposes can be used under the conditions of "5. Terms of Use". The dataset has been generated from the DSM dataset (5-meter mesh version) of the precise global digital 3D map "ALOS World 3D" (AW3D), which is the world’s first and the most precise 3D map covering all global land scales with 5 meter mesh. In the previous version 1.1 released in March 2017, void height values in the cloud and snow pixels between 60-degree North and 60-degree South were filled with existing DEMs.

In the newly released version 2.1, the source of AW3D has been upgraded to version 2 (Takaku and Tadono, 2017), and masks of the water and low correlation pixels were also filled with existing DEMs in addition to the cloud and snow pixels between 60-degree North and 60-degree South. In Japan area, filling was carried out after updating coastline information.

Note that only AVERAGE resampling product is provided in version 2.1 though there were two types of resampling method in previous version i.e. AVERAGE and MEDIAN, but since there is not much difference between them.

This dataset is highly expected to be useful for scientific research, education, as well as the private service sector that uses geospatial information.

2. Release History

  • April 2018: Update 14,535 tiles with void-filled DSM within 60 deg. of N/S and partly over 60 deg. of N (Version 2.1)
    • ◦ The main improvements of AW3D Version 2 are following;
      • Absolute offset errors from the ICESat reference, and
      • Relative striping errors along satellite orbits by updated calibration.
    • ◦ Out of the areas are same with Version 1 product.
  • March 2017: Update with void-filled DSM within 60 deg. of N/S latitudes as Version 1.1
    • ◦ Void pixels due to clouds and snow pixels within 60 deg. of north and south latitudes in Version 1 were complemented by existing DEMs.
  • May 2016: Global terrestrial region (within approx. 82 deg. of N/S latitudes) of Version 1 released (approx. 22,100 tiles).
  • April 2016: Version 1 covering Japan and a part of individual continent released (Total 7,278 tiles).
  • May and October 2015: Japan and a part of individual continent released as Beta Version (Total 7,279 tiles).

3. Descriptions of the AW3D30 DSM dataset

Product: ALOS World 3D – 30m (AW3D30) Version 2.1
Resolution: 1 arcsecond (approx. 30m mesh)
File Unit: 1 × 1 degree Latitude/Longitude Tile
Height accuracy: Targets :5 meters as standard deviation (1 sigma)∗1
File Composition: DSM file; Height above sea level.∗2
MSK file; Mask information for each pixel (Cloud/Snow Mask, Land water and low correlation mask, Sea mask, Information of elevation dataset used for the void-filling processing).
STK file; Number of DSM-scene files which were used to produce the 5m resolution DSM.
QAI file; Quality assurance Information.
HDR file; Meta information such as image size and pixel spacing
LST file; Information of scene IDs which were used to produce the AW3D-DSM.
Document: AW3D30 Version 2.1 Product Description (PDF format 350KB)

∗1 Please refer to papers listed in the section "8 Reference" in this page.
∗2 The low quality pixels (water and low correlation pixels) were filled in addition to the cloud and snow pixels in version 2.1.

4. Download

The dataset is downloadable from following;

http://www.eorc.jaxa.jp/ALOS/en/aw3d30/data/index.htm

To download the data files, you are kindly requested to make your account in the AW3D30 homepage and if you forget your password, please register again.

User Registration
1. Please fill the form in the following URL and send it.

http://www.eorc.jaxa.jp/ALOS/en/aw3d30/registration.htm

2. The notification of registration completion will be sent to your e-mail address. Please access to the URL described in the e-mail and then your account will be activated.
3. After the account activation, we will send your account information to your e-mail address.

JAXA will not use personal information that you registered for any purpose other than "ALOS World 3D"(AW3D).

5. Terms of Use for ALOS Global Digital Surface Model (AW3D30)

This dataset is available to use with no charge under the following conditions.

  •  When you provide or publish any products and services to a third party using this dataset, you are kindly requested to display that the original data is provided by JAXA.
  •  When you publish the product(s) using this dataset, you are kindly requested to show the copyright (©JAXA) and the source of data.
  •  JAXA does not guarantee the quality and reliability of this dataset and JAXA assume no responsibility whatsoever for any direct or indirect damage and loss caused by use of this dataset. Also, JAXA will not be responsible for any damages of users due to changing, deleting or terminating the provision of this dataset.

JAXA handles the personal information such as names and e-mail addresses in accordance with JAXA's rules on protection of personal information. For details, please refer to "Privacy Policy" in the JAXA's site; (http://global.jaxa.jp/policy.html)

We would be very grateful if you could send some published results, or any comments to , for our future reference

6. Notes

(1) Access to the data download page

When access to the data download page, you are requested ID and password which are sent by e-mail after completion of user registration. Please make your account in the user registration form.

Username: <ID notified by e-mail>
Password: <password notified by e-mail> (character string excluding blanks only)

Please note that there are a lot of input errors. We recommend that you copy and paste ID and password notified by e-mail. Be careful not to include blank characters when copying and pacing.

If you make a mistake several times, your web session will be locked. If the session is locked, please wait for more than 20 minutes and try again. The lock will be automatically canceled after 20 minutes. Also, if the notification mail does not arrive or lost, please register again and the latest password will be effective.

(2) Data file

After login to the download page, please click the required data location on the map, you can download data file divided into 1 × 1 degree unit or 5 × 5 degree unit in latitude and longitude.

The downloaded file is compressed into one file by tar.gz. Software may be required for this decompression. For example, 7-Zip is available as free software.

(3) Data Display

The format of DSM data file is GeoTIFF. To display and process the data, software such as image processing, remote sensing, GIS, etc. is required.

(4) Data conversion

Sample script for format conversion from AW3D30 DSM GeoTIFF to SRTM HGT format

This is a sample script to convert AW3D30 DSM file (GeoTIFF) to SRTM HGT format. The sample script use the GDAL for format conversion. Please prepare an environment which can use GDAL. For usage, please refer to "readme-en.txt" composed in the zip file.

(a) System requirements
This sample script operates with Linux system, and requires "GDAL", "bash", and "awk". We also confirmed that the script works on the following environment except for Linux system.

(b) Note: Usage of script
To perform resampling of the edge portion of the tile accurately, AW3D30 for input is needed the tile which is not only the tile you want to convert but also surrounding tiles. Please prepare the AW3D30 data for larger areas than your interest.

(c) Disclaimers
Regardless of the reason, JAXA shall not be made liable for any damage or loss as a result of the use of this sample script.

7. Contact

ALOS Science Project
Earth Observation Research Center (EORC)
Japan Aerospace Exploration Agency (JAXA)
E-mail:

* Please contact us in English or Japanese.

8. Reference

T. Tadono, H. Ishida, F. Oda, S. Naito, K. Minakawa, H. Iwamoto : Precise Global DEM Generation By ALOS PRISM, ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol.II-4, pp.71-76, 2014.
>> PDF file

J. Takaku, T. Tadono, K. Tsutsui : Generation of High Resolution Global DSM from ALOS PRISM, The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol. XL-4, pp.243-248, ISPRS, 2014.
>> PDF file

J. Takaku, T. Tadono, K. Tsutsui, M. Ichikawa : Validation of ‘AW3D’ Global DSM Generated from ALOS PRISM, ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol.III-4, pp.25-31, 2016.
>> PDF file

T. Tadono, H. Nagai, H. Ishida, F. Oda, S. Naito, K. Minakawa, H. Iwamoto : Initial Validation of the 30 m-mesh Global Digital Surface Model Generated by ALOS PRISM, The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, ISPRS, Vol. XLI-B4, pp.157-162, 2016.
>> PDF file

J. Takaku and T. Tadono, “Quality updates of ‘AW3D’ global DSM generated from ALOS PRISM,” Proc. IGARSS2017, IEEE, Fort Worth, TX, USA., pp. 5666-5669, 2017.
>> https://ieeexplore.ieee.org/document/8128293/