Will ASF HyP3 support NISAR? Any roadmap/timeline?

[iwa103]

In many Southeast Asian countries, purchasing ALOS data for SBAS analysis is often economically difficult. In this context, open L-band data from NISAR would be extremely valuable.

In addition, preparing high-performance computers for InSAR processing is often not feasible in these regions. Therefore, cloud-based services such as HyP3, which allow interferometric processing without requiring high local computing resources, are particularly beneficial.

[ASF - bhauer]

ALOS-2 PALSAR-2 ScanSAR Level 1.1 data are available from ASF. Data continue to be received from JAXA with the intention of creating a mirror archive of the global JAXA catalogue. Current ALOS-2 coverage includes regions in the northern parts of Southeast Asia. If there are specific areas where coverage is desired, let us know, and we can prioritize the transfer of these data.

As with all data available from ASF, they are free and open to anyone.

[iwa103]

Thank you for the information.

ALOS-2 ScanSAR data are indeed very useful, but currently the openly available dataset appears to extend only until around March 2025. Data acquired after that time are not yet publicly available. In addition, since ALOS-4 began operations in the latter half of last year, the situation for L-band data has effectively changed.

For time-series InSAR analysis such as SBAS, the observation interval is a critical factor. ALOS-2 typically has revisit intervals of several months in many regions, which makes it difficult to apply SBAS effectively. ALOS-4 improves this with an observation interval of roughly two weeks, but the data are commercial, so it is not easy for many users to access them regularly.

As a result, at present the only L-band SAR mission providing regularly observed and open data suitable for SBAS is NISAR. This is particularly important for regions with dense vegetation, such as Southeast Asia and island countries like New Zealand, where L-band observations are generally preferred for interferometric analysis.

For these reasons, the availability of open L-band datasets with consistent temporal coverage is extremely important for the wider InSAR community.

[ASF - bhauer]

For everyone's information, recent ALOS-2 PALSAR-2 ScanSAR acquisitions will not be available from ASF as long as the satellite is active, as this is still considered a commercial mission.