The dataset contains all ESA acquisitions over the ADEN zone (Europe, Africa and the Middle East) plus some products received from JAXA over areas of interest around the world. Further information on ADEN zones can be found in this technical note. ALOS PALSAR products are available in following modes: Fine Beam Single polarisation (FBS), single polarisation (HH or VV), swath 40-70 km, resolution 10 m, temporal coverage from 02/05/2006 to 30/03/2011 Fine Beam Double polarisation (FBD), double polarisation (HH/HV or VV/VH), swath 40-70 km, resolution 10 m, temporal coverage from 02/05/2006 to 30/03/2011 Polarimetry mode (PLR), with four polarisations simultaneously: swath 30 km, resolution 30 m, temporal coverage from 26/08/2006 to 14/04/2011 ScanSAR Burst mode 1 (WB1), single polarisation: swath 250-350 km, resolution 100 m, temporal coverage from 12/06/2006 to 21/04/2011. Following processing levels are available: RAW (Level 1.0): Raw data generated by every downlink segment and every band. Divided into an equivalent size to one scene SLC (Level 1.1): Slant range single look complex product. Not available for WB1 GDH (Level 1.5): Ground range Detected, Normal resolution product GEC (Level 1.5): Geocoded product. The table summarises the ALOS PALSAR offer. Instrument mode Product type Processing level description JAXA processing level equivalent Fine Beam Single polarisation (HH or VV) FBS_RAW_0P Raw data generated by every downlink segment and every band. Divided into an equivalent size to one scene 1.0 FBS_GDH_1P Ground range Detected, Normal resolution product 1.5 FBS_GEC_1P Geocoded product 1.5 FBS_SLC_1P Slant range single look complex product 1.1 Fine Beam Double polarisation (HH/HV or VV/VH) FBD_RAW_0P Raw data generated by every downlink segment and every band. Divided into an equivalent size to one scene 1.0 FBD_GDH_1P Ground range Detected, Normal resolution product 1.5 FBD_GEC_1P Geocoded product 1.5 FBD_SLC_1P Slant range single look complex product 1.1 Polarimetry mode (4 polarisation) PLR_RAW_0P Raw data generated by every downlink segment and every band. Divided into an equivalent size to one scene 1.0 PLR_GDH_1P Ground range Detected, Normal resolution product 1.5 PLR_GEC_1P Geocoded product 1.5 PLR_SLC_1P Slant range single look complex product 1.1 ScanSAR Burst mode 1 (single polarisation) WB1_RAW_0P Raw data generated by every downlink segment and every band. Divided into an equivalent size to one scene 1.0 WB1_GDH_1P Ground range Detected, Normal resolution product 1.5 WB1_GEC_1P Geocoded product 1.5

A newer version of this dataset with data for 2015-2021 can be found in JAXA/ALOS/PALSAR/YEARLY/SAR_EPOCH The global 25m PALSAR/PALSAR-2 mosaic is a seamless global SAR image created by mosaicking strips of SAR imagery from PALSAR/PALSAR-2. For each year and location, the strip data were selected through visual inspection of the browse mosaics available over the period, with those showing minimum response to surface moisture preferentially used. In cases where the availability was limited (e.g., because of the requirement for observations during specific emergencies), data were necessarily selected from the year before or after, including from 2006. Shimada et al. 2014 There is no data for 2011-2014 due to the gap between ALOS and ALOS-2 temporal coverage. The SAR imagery was ortho-rectificatied and slope corrected using the 90m SRTM Digital Elevation Model. A destriping process (Shimada & Isoguchi, 2002, 2010) was applied to equalize the intensity differences between neighboring strips, occurring largely due to seasonal and daily differences in surface moisture conditions. Polarization data are stored as 16-bit digital numbers (DN). The DN values can be converted to gamma naught values in decibel unit (dB) using the following equation: γ₀ = 10log₁₀(DN²) - 83.0 dB Attention: Backscatter values may vary significantly from path to path over high latitude forest areas. This is due to the change of backscattering intensity caused by freezing trees in winter. More information is available in the provider's Dataset Description.

ALOS PALSAR Level 1.0

ALOS PALSAR Level 2.2

ALOS PALSAR Level 1.1

The GMW has generated a global baseline map of mangroves for 2010 using ALOS PALSAR and Landsat (optical) data, and changes from this baseline for epochs between 1996 and 2020 derived from JERS-1 SAR, ALOS PALSAR and ALOS-2 PALSAR-2. Annual maps are planned from 2015 and onwards.

The Global Mangrove Watch (GMW) was initiated as part of the JAXAKyoto & Carbon Initiative in 2011. It is led by Aberystwyth University and solo Earth Observation, in collaboration with Wetlands International, the International Water Management Institute and the UN Environment World Conservation Monitoring Centre (U.K.). The African part is supported by DOB Ecology through the Mangrove Capital Africaproject. The GMW aims to provide geospatial information about mangrove extent and changes to the Ramsar Convention, national wetland practitioners, decision makers and NGOs. It is part of the Ramsar Science and Technical Review Panel (STRP) work plan for 2016-2018 and a Pilot Project to the Ramsar Global Wetlands Observation System (GWOS), which is implemented under the GEO-Wetlands Initiative. The primary objective of the GMW has been to provide countries lacking a national mangrove monitoring system with first cut mangrove extent and change maps, to help safeguard against further mangrove forest loss and degradation.The GMW has generated a global baseline map of mangroves for 2010 using ALOS PALSAR and Landsat (optical) data, and changes from this baseline for six epochs between 1996 and 2016 derived from JERS-1 SAR, ALOS PALSAR and ALOS-2 PALSAR-2. Annual maps are planned from 2018 and onwards. Currently only the 2010 layer has been validated and is available for download. Validation of the other layers is ongoing and public release planned for early 2019.Metadata:The document is available at this URL: Global Mangroove Watch

The Global Mangrove Watch (GMW) is a collaboration between Aberystwyth University (U.K.), solo Earth Observation (soloEO; Japan), Wetlands International the World Conservation Monitoring Centre (UNEP-WCMC) and the Japan Aerospace Exploration Agency (JAXA).

The GMW aims to provide geospatial information about mangrove extent and changes to the Ramsar Convention, national wetland practitioners, decision makers and NGOs. It is part of the Ramsar Science and Technical Review Panel (STRP) work plan for 2016-2018 and a Pilot Project to the Ramsar Global Wetlands Observation System (GWOS), which is implemented under the GEO-Wetlands Initiative. The primary objective of the GMW has been to provide countries lacking a national mangrove monitoring system with first cut mangrove extent and change maps, to help safeguard against further mangrove forest loss and degradation.

The GMW has generated a global baseline map of mangroves for 2010 using ALOS PALSAR and Landsat (optical) data, and changes from this baseline for seven epochs between 1996 and 2017 derived from JERS-1, ALOS and ALOS-2. Annual maps are planned from 2018 and onwards.

Citations: Bunting P., Rosenqvist A., Lucas R., Rebelo L-M., Hilarides L., Thomas N., Hardy A., Itoh T., Shimada M. and Finlayson C.M. (2018). The Global Mangrove Watch – a New 2010 Global Baseline of Mangrove Extent. Remote Sensing 10(10): 1669. doi: 10.3390/rs1010669. Other cited references: Thomas N, Lucas R, Bunting P, Hardy A, Rosenqvist A, Simard M. (2017). Distribution and drivers of global mangrove forest change,