Date of Images:

May 5, 2024, August 9, 2024, August 21, 2024

Summary:

The Advanced Rapid Imaging and Analysis (ARIA) and Observational Products for End-Users from Remote Sensing Analysis (OPERA) teams at NASA's Jet Propulsion Laboratory and California Institute of Technology derived the surface water extent maps from Sentinel-1.

The results posted here are preliminary and unvalidated results, primarily intended to aid the field response and people who wanted to have a rough first look at the inundation extent. The ARIA-share website has always focused on posting preliminary results as fast as possible for disaster response.

Suggested Use:

The OPERA DSWx-S1 products classifies the OPERA Radiometric Terrain Corrected SAR backscatter from Sentinel-1 (RTC-S1) input imagery into: not water, water, and inundated vegetation with the masks such as layover/shadow mask and HAND mask. The WTR layer includes all classes. Open water and inundated vegetation are represented in blue and green in WTR. Areas with masks are gray. The masks include the layover/shadow mask and HAND mask. Areas with no water detected are transparent.

• Transparent: Not Water

• Blue: Water

• Green: Inundated Vegetation

• Gray: Layover/Shadow/Hand Masks

Satellite/Sensor:

Synthetic Aperture Radar (SAR) instrument on European Space Agency's (ESA) Sentinel-1A satellite

Harmonized Landsat Sentinel-2 (HLS): MultiSpectral Instrument (MSI) on European Space Agency's (ESA) Copernicus Sentinel-2A/2B satellites and Operational Land Imager (OLI) on the NASA/USGS Landsat 8 satellite

Resolution:

30 meters

The DSWx-S1 products have these flags:

250 (light gray) and 251 (dark gray) represent HAND and layover/shadow masks, respectively.

HAND mask (light gray, value 250) delineates regions where the terrain's elevation exceeds a specified threshold relative to the height above the nearest drainage point, indicating areas less likely to be subject to direct inundation. Layover/shadow mask (dark gray, value 251) identifies zones that are either occluded by topographic features taller than the surrounding landscape (layover) or are not illuminated by the radar signal due to obstruction by these elevated features (shadow), leading to potential data voids in SAR imagery.

Credits:

NASA JPL-Caltech ARIA/OPERA Team

Sentinel-1 data were accessed through the Copernicus Open Hub and the Alaska Satellite Facility server. The product contains modified Copernicus Sentinel data (2024), processed by the European Space Agency and analyzed by the NASA-JPL/Caltech ARIA and OPERA team. The products are produced as part of the OPERA project, which is funded by NASA to address remote sensing needs identified by the Satellite Needs Working Group, and managed by NASA's Jet Propulsion Laboratory.

The OPERA DSWx products have been in production since September 2024, are freely distributed to the public via NASA's Physical Oceanography Distributed Active Archive Center (PO.DAAC), and can be downloaded through NASA's Earthdata search. For more information about the Dynamic Surface Water eXtent product suite, please refer to the DSWx Product page: https://www.jpl.nasa.gov/go/opera/products/dswx-product-suite.

For more information about the Caltech-JPL ARIA project, visit https://aria.jpl.nasa.gov.

For more information about the JPL OPERA project, visit https://www.jpl.nasa.gov/go/opera.

Date of Images:

May 5, 2024, August 9, 2024, August 21, 2024

Summary:

The Advanced Rapid Imaging and Analysis (ARIA) and Observational Products for End-Users from Remote Sensing Analysis (OPERA) teams at NASA's Jet Propulsion Laboratory and California Institute of Technology derived the surface water extent maps from Sentinel-1.

The results posted here are preliminary and unvalidated results, primarily intended to aid the field response and people who wanted to have a rough first look at the inundation extent. The ARIA-share website has always focused on posting preliminary results as fast as possible for disaster response.

Suggested Use:

The OPERA DSWx-S1 products classifies the OPERA Radiometric Terrain Corrected SAR backscatter from Sentinel-1 (RTC-S1) input imagery into: not water, water, and inundated vegetation with the masks such as layover/shadow mask and HAND mask. The WTR layer includes all classes. Open water and inundated vegetation are represented in blue and green in WTR. Areas with masks are gray. The masks include the layover/shadow mask and HAND mask. Areas with no water detected are transparent.

• Transparent: Not Water

• Blue: Water

• Green: Inundated Vegetation

• Gray: Layover/Shadow/Hand Masks

Satellite/Sensor:

Synthetic Aperture Radar (SAR) instrument on European Space Agency's (ESA) Sentinel-1A satellite

Harmonized Landsat Sentinel-2 (HLS): MultiSpectral Instrument (MSI) on European Space Agency's (ESA) Copernicus Sentinel-2A/2B satellites and Operational Land Imager (OLI) on the NASA/USGS Landsat 8 satellite

Resolution:

30 meters

The DSWx-S1 products have these flags:

250 (light gray) and 251 (dark gray) represent HAND and layover/shadow masks, respectively.

HAND mask (light gray, value 250) delineates regions where the terrain's elevation exceeds a specified threshold relative to the height above the nearest drainage point, indicating areas less likely to be subject to direct inundation. Layover/shadow mask (dark gray, value 251) identifies zones that are either occluded by topographic features taller than the surrounding landscape (layover) or are not illuminated by the radar signal due to obstruction by these elevated features (shadow), leading to potential data voids in SAR imagery.

Credits:

NASA JPL-Caltech ARIA/OPERA Team

Sentinel-1 data were accessed through the Copernicus Open Hub and the Alaska Satellite Facility server. The product contains modified Copernicus Sentinel data (2024), processed by the European Space Agency and analyzed by the NASA-JPL/Caltech ARIA and OPERA team. The products are produced as part of the OPERA project, which is funded by NASA to address remote sensing needs identified by the Satellite Needs Working Group, and managed by NASA's Jet Propulsion Laboratory.

The OPERA DSWx products have been in production since September 2024, are freely distributed to the public via NASA's Physical Oceanography Distributed Active Archive Center (PO.DAAC), and can be downloaded through NASA's Earthdata search. For more information about the Dynamic Surface Water eXtent product suite, please refer to the DSWx Product page: https://www.jpl.nasa.gov/go/opera/products/dswx-product-suite.

For more information about the Caltech-JPL ARIA project, visit https://aria.jpl.nasa.gov.

For more information about the JPL OPERA project, visit https://www.jpl.nasa.gov/go/opera.