Antarctic Sea Ice Surface Melt evaluated from Satellite Remote Sensing Data
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This folder contains optical and passive microwave data which reflects the presence of surface melt on Antarctic sea ice 2002-2024. 
The data have been obtained within the REASSESS DFG project (PI L.Istomina, duration 2019-2024, grant number 424326801).

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The optical data are obtained from MERIS on Envisat according to Istomina et al., 2020 and OLCI on Sentinel-3A/B data, according to Istomina et al., 2025, applied to the Antarctic sea ice within the REASSESS project.
The optical data netCDF files contain daily averages of melt pond fractions and spectral albedo at 400,500,600,700,800,900 according to Istomina et al., (2020, 2025),
and broadband albedo calculated from spectral albedo according to Pohl et al., 2020. 
The naming convention for optical data: "Ant_Surface_Melt_VIS_*.nc", where * is the date as YYYYMMDD.

The passive microwave data are obtained from AMSR-E/AMSR-2 data using a melt pond fraction retrieval algorithm by Tanaka et al., 2016, adapted to the Antarctic sea ice conditions within the REASSESS project.
The passive microwave netCDF files contain melt pond fractions (MPF) limited to areas of longterm landfast ice persistance according to Fraser et al., (2021), or areas of pack ice where OSISAF sea ice concentration is greater than 97%. In addition, the passive microwave data netCDF files contain cumulatve melting degree day (CMDD) index (Mäkynen et al., 2020) produced out of ECMWF ERA5 2m surface air temperature and melt stage index (MSI) as defined for the Arctic by Mäkynen et al., (2020). 
The naming convention for passive microwave data: "Ant_Surface_Melt_AMSR_*.nc", where * is the date as YYYYMMDD.

All MPF and albedo data have been masked with the yearly ice mask by Chad et al., 2022. 
All data have been gridded into the 12.5km polar stereographic grid for the Southern Hemisphere https://nsidc.org/data/polar-stereo/ps_grids.html
The grid coordinates are not included into the files and can be found here:
https://data.seaice.uni-bremen.de/data/grid_coordinates/s12500/LongitudeLatitudeGrid-s12500-Antarctic.hdf
or
https://data.seaice.uni-bremen.de/data/SurfaceMelt/LongitudeLatitudeGrid-s12500-Antarctic.h5

The data is available for austral summers 2002-2024 from the 1st of December to end of February.
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