NISAR Hawaii Volcanoes -- Search, Inspect, and Subset Examples¶

End-to-end examples for RSLC, GSLC, and GCOV products covering Hawaii Volcanoes National Park (Kilauea caldera and active lava flows).

All examples use Track 072, Frame 079 (Descending, Dual-pol HH+HV) and a geographic bbox over Kilauea: -155.33 19.47 -155.20 19.37. Each command completes in under 1 minute from a laptop over HTTPS.

1. Search for Products¶

Find all product types over Hawaii Big Island¶

seppo_nisar_search \
    --product GCOV \
    --bbox -156.1 19.3 -154.8 20.3 \
    --start_time_after 2026-01-01 \
    --start_time_before 2026-04-01 \
    --https \
    --limit 30 \
    --group

Save Track 072 Frame 079 URLs for batch processing¶

# GCOV
seppo_nisar_search --product GCOV --track 72 --frame 79 --direction D \
    --start_time_after 2026-01-01 --start_time_before 2026-04-01 \
    --https --group -o search_results/

# GSLC
seppo_nisar_search --product GSLC --track 72 --frame 79 --direction D \
    --start_time_after 2026-01-01 --start_time_before 2026-04-01 \
    --https --group -o search_results/

# RSLC
seppo_nisar_search --product RSLC --track 72 --frame 79 --direction D \
    --start_time_after 2026-01-01 --start_time_before 2026-04-01 \
    --https --group -o search_results/

2. Inspect Products¶

Inspect RSLC structure¶

seppo_nisar_rslc_convert -lg -i \
    https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L1_RSLC_BETA_V1/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5

Inspect GCOV structure¶

seppo_nisar_gcov_convert -lg -i \
    https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GCOV_BETA_V1/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5

Inspect GSLC structure¶

seppo_nisar_gslc_convert -lg -i \
    https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GSLC_BETA_V1/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5

3. RSLC Subsetting¶

Subset Kilauea area (HH only, with quicklook)¶

seppo_nisar_rslc_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L1_RSLC_BETA_V1/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/rslc/ \
    -projwin -155.33 19.47 -155.20 19.37 \
    -vars HH \
    -ql -v

Output: 43 MB subsetted RSLC HDF5 + quicklook PNG (~32 seconds, no caching). The quicklook shows Kilauea caldera clearly visible as a dark oval (smooth lava lake).

Dual-pol subset (HH + HV)¶

seppo_nisar_rslc_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L1_RSLC_BETA_V1/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/rslc/ \
    -projwin -155.33 19.47 -155.20 19.37 \
    -vars HH HV \
    -ql -v

Output to S3¶

seppo_nisar_rslc_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L1_RSLC_BETA_V1/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L1_PR_RSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o s3://mybucket/hawaii/rslc/ \
    -projwin -155.33 19.47 -155.20 19.37 \
    -vars HH HV \
    --output_profile myprofile \
    -v

4. GCOV Conversion and Subsetting¶

Convert to amplitude COG over Kilauea¶

seppo_nisar_gcov_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GCOV_BETA_V1/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/gcov/ \
    -amp \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -v

Sigma0 reprojected to WGS84¶

seppo_nisar_gcov_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GCOV_BETA_V1/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/gcov/ \
    -sigma0 \
    -t_srs 4326 -tr 0.0002 0.0002 \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -v

Time series (batch from search output)¶

seppo_nisar_gcov_convert \
    -i search_results/NISAR_GCOV_072_D_079_*.txt \
    -o output/gcov_timeseries/ \
    -amp \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -v

Dual-pol ratio¶

seppo_nisar_gcov_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GCOV_BETA_V1/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GCOV_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/gcov/ \
    -dpratio \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -v

5. GSLC Conversion and Subsetting¶

Convert to power COG¶

seppo_nisar_gslc_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GSLC_BETA_V1/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/gslc/ \
    -pwr \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -v

Extract raw complex SLC for interferometry¶

seppo_nisar_gslc_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GSLC_BETA_V1/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/gslc/ \
    -cslc \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -vars HH \
    -v

Subset to HDF5 (preserves complex data + all metadata)¶

seppo_nisar_gslc_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GSLC_BETA_V1/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/gslc/ \
    -of h5 \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -v

Extract wrapped phase¶

seppo_nisar_gslc_convert \
    -i https://nisar.asf.earthdatacloud.nasa.gov/NISAR/NISAR_L2_GSLC_BETA_V1/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001/NISAR_L2_PR_GSLC_009_072_D_079_4005_DHDH_A_20260102T045817_20260102T045836_X05010_N_P_J_001.h5 \
    -o output/gslc/ \
    -phase \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -vars HH \
    -v

6. Batch Processing (Time Series)¶

GCOV time series¶

# Step 1: Search and save URLs
seppo_nisar_search --product GCOV \
    --track 72 --frame 79 --direction D \
    --start_time_after 2026-01-01 --start_time_before 2026-07-01 \
    --https --group \
    -o search_results/

# Step 2: Convert all to COG with subsetting
seppo_nisar_gcov_convert \
    -i search_results/NISAR_GCOV_072_D_079_*.txt \
    -o output/gcov_timeseries/ \
    -amp \
    -projwin -155.33 19.47 -155.20 19.37 \
    -projwin_srs EPSG:4326 \
    -v

RSLC time series for interferometry¶

# Search
seppo_nisar_search --product RSLC \
    --track 72 --frame 79 --direction D \
    --start_time_after 2026-01-01 --start_time_before 2026-07-01 \
    --https --group \
    -o search_results/

# Subset all to the same geographic extent
seppo_nisar_rslc_convert \
    -i search_results/NISAR_RSLC_072_D_079_*.txt \
    -o output/rslc_stack/ \
    -projwin -155.33 19.47 -155.20 19.37 \
    -vars HH \
    -v

Each output is a fully self-contained RSLC HDF5 that can be processed independently with isce3, GAMMA Remote Sensing, or SEPPO.

Area of Interest¶

Parameter	Value
Location	Hawaii Volcanoes National Park (Kilauea)
Bounding box (lon/lat)	`-155.33 19.47 -155.20 19.37`
NISAR Track	072
NISAR Frame	079
Direction	Descending
Polarisation	Dual-pol HH+HV (DHDH)
First acquisition	2026-01-02
Repeat cycle	12 days

This area features active lava flows, caldera structures, tropical rainforest, and bare lava fields -- ideal for demonstrating SAR processing capabilities.