4.4. AVHRR Reader

The AVHRR reader is for reading AAPP L1B files for the AVHRR instrument.

These files are a custom binary format. The reader can be specified with the polar2grid.sh command using the avhrr or avhrr_l1b_aapp reader name.

This reader’s default resampling algorithm is ewa for Elliptical Weighted Averaging resampling. The --weight-delta-max option is set to 10 and --weight-distance-max is set to 1.

The AVHRR reader provides the following products:

Product Name	Description
band1_vis	Band 1 Visible
band2_vis	Band 2 Visible
band3a_vis	Band 3A Visible
band3b_bt	Band 3B Brightness Temperature
band4_vis	Band 4 Brightness Temperature
band5_vis	Band 5 Brightness Temperature

4.4.1. Command Line Arguments

usage: polar2grid.sh -r avhrr_l1b_aapp -w <writer> [-h]

4.4.2. Execution Examples

polar2grid.sh -r avhrr_l1b_aapp -w awips_tiled --list-products -f /l1b/

polar2grid.sh -r avhrr_l1b_aapp -w geotiff -f ../input/hrpt_noaa19_20220917_1236_70145.l1b

polar2grid.sh -r avhrr -w geotiff -p band3a_vis band4_bt -f /data/hrpt_M03*.l1b

polar2grid.sh -r avhrr -w awips_tiled -p band3b_bt -g lcc_conus_1km --sector-id LCC --letters --compress -f hrpt_noaa18_20220918_1708_89324.l1b

polar2grid.sh -r avhrr_l1b_aapp -w awips_tiled --num-workers 6 --grid-coverage .002 -g polar_alaska_1km --sector-id Polar --letters --compress -f /avhrr

polar2grid.sh -r avhrr -w hdf5 --add-geolocation --grid-configs /home/avhrr/grids/local_grid.yaml -g my_grid  -f ../input/hrpt_M01*.l1b

polar2grid.sh -r avhrr -w binary --num-workers 8 -p band1_vis band4_bt -g lcc_eu -f /data/avhrr/metoba