A comparison of sea ice parameters computed from advanced very high resolution radiometer and Landsat satellite imagery and from airborne passive microwave radiometry

Abstract

The advanced very high resolution radiometer (AVHRR), flying on the NOAA polar‐orbiting weather satellites, can be used to map both sea ice concentration and ice edge, under cloud‐free conditions. In order to evaluate the accuracy and reliability of these AVHRR ice parameters, we have compared AVHRR‐derived sea ice parameters from the Bering Sea with those computed from nearly coincident (within 6 hours) Landsat multispectral scanner (MSS) imagery and from the aircraft multichannel microwave radiometer (AMMR) flown on the NASA DC‐8. The higher spatial and spectral resolutions of the Landsat data make them appropriate to use as a reference for the AVHRR inferred sea ice parameters while the lower‐altitude aircraft microwave sensor also provides a good source of comparison data. Both the AVHRR near‐infrared (channel 2) and thermal infrared (channel 4) images were used to compute ice concentration. Mean ice concentration differences between the channel 2 AVHRR and Landsat MSS data (Landsat‐AVHRR) ranged from −0.8 to 1.8% with a mean value of 0.5%. Root‐mean‐square (rms) differences ranged from 6.8 to 17.7%. Mean differences were larger for the channel 4 AVHRR ice concentrations ranging from −2.2 to 8.4% with rms differences from 8.6 to 26.8%. Mean differences between AVHRR channel 2 concentrations and the AMMR data (AMMR‐AVHRR) ranged from −19.7 to 18.9% while rms values went from 17.0 to 44.8%. Mean ice edge differences between the Landsat and AVHRR images were 1.8 km for channel 2 and 2.9 km for channel 4 with rms differences of 3.2 km and 4.4 km, respectively. The AVHRR ice edge was south and west of the Landsat edge.