ALOS-2 PALSAR-2 StripMap Level 2.1

JAXA/ALOS/PALSAR-2/Level2_1/StripMap_202401
Dataset Availability
2022-09-26T00:00:00Z–2024-01-08T00:00:00Z
Dataset Provider
Earth Engine Snippet
ee.ImageCollection("JAXA/ALOS/PALSAR-2/Level2_1/StripMap_202401")

Description

Starting from the night of January 1st, 2024, based on the request from Japanese ministries and related organization, JAXA implemented ALOS-2 PALSAR-2 emergency observation. Since JAXA expects these emergency observation data to be extremely useful for disaster management, JAXA decided to open these data on Google Earth Engine for public and research usage.

JAXA released PALSAR-2 Level 2.1 strip map mode observation data with 3m single polarization for January 1-3 and January 8 2024, together with some archive data. PALSAR-2 Level 2.1 data is orthorectified from level 1.1 data by using digital elevation model. The DN values can be converted to sigma naught values in decibel unit (dB) using the following equation:

  • σ0 = 10*log10(DN2) - 83.0 dB

Below are the dates for which the dataset has data.

Obs date Frame Beam A/D
2024/01/01 and 2022/09/26 0750, 0760, 0770 U2-6L Asc.
2024/01/02 and 2023/06/06 2820, 2830, 2840 U2-8L Desc.
2024/01/08, 2024/01/03 and 2023/12/06 0720, 0730 U2-9R Asc.

Bands

Resolution
3 meters

Bands

Name Description
b1

HH polarization Terrain-flattened Gamma-Nought backscatter coefficient.

Terms of Use

Terms of Use

Anyone can use this data free of charge subject to non-commercial use only. For detailed terms of use see JAXA G-Portal Terms of service (Section 7. Condition concerning of G-Portal data).

Citations

Citations:
  • The data used for this paper have been provided by Earth Observation Research Center (EORC) of Japan Aerospace Exploration Agency (JAXA).

Explore with Earth Engine

Code Editor (JavaScript)

var coll = ee.ImageCollection('JAXA/ALOS/PALSAR-2/Level2_1/StripMap_202401');

var vis = {min: 0, max: 8000};

// Visualize different date ranges
var visualizeDateRange = function(startDate, endDate, layerName) {
  var dateRange = coll.filterDate(startDate, endDate);
  Map.addLayer(dateRange, vis, layerName);
};

visualizeDateRange('2023-06-06', '2023-06-07', 'Before-2023-06-06');
visualizeDateRange('2023-06-12', '2023-06-13', 'Before-2023-06-12');
visualizeDateRange('2022-09-26', '2022-09-27', 'Before-2022-09-26');
visualizeDateRange('2023-12-06', '2023-12-07', 'Before-2023-12-06');
visualizeDateRange('2024-01-01', '2024-01-02', 'After-2024-01-01');
visualizeDateRange('2024-01-02', '2024-01-03', 'After-2024-01-02');
visualizeDateRange('2024-01-03', '2024-01-04', 'After-2024-01-03');
visualizeDateRange('2024-01-08', '2024-01-09', 'After-2024-01-08');

Map.setCenter(137.2228, 37.1204, 8);
Open in Code Editor