Deploying deep learning on Synthetic Aperture Radar (SAR) data is becoming more common for mapping purposes. One such case is sea ice, which is highly dynamic and rapidly changes as a result of the combined effect of wind, temperature, and ocean currents. Therefore, frequent mapping of sea ice is necessary to ensure safe marine navigation. However, there is a general shortage of expert-labeled data to train deep learning algorithms. Fine-tuning a pre-trained model on SAR imagery is a potential solution. In this paper, we compare the performance of deep learning models trained from scratch using randomly initialized weights against pre-trained models that we fine-tune for this purpose. Our results show that pre-trained models lead to better results, especially on test samples from the melt season.
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Deep Sensing of Ocean Wave Heights with Synthetic Aperture Radar.
The Sentinel-1 satellites equipped with synthetic aperture radars (SAR) provide near global coverage of the world’s oceans every six days. We curate a data set of co-locations between SAR and altimeter satellites, and investigate the use of deep learning to predict significant wave height from SAR. While previous models for predicting geophysical quantities from SAR rely heavily on feature-engineering, our approach learns directly from low-level image cross-spectra. Training on co-locations from 2015-2017, we demonstrate on test data from 2018 that deep learning reduces the state-of-the-art root mean squared error by 50%, from 0.6 meters to 0.3 meters.
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- Award ID(s):
- 1920304
- PAR ID:
- 10273998
- Date Published:
- Journal Name:
- AAAI 2020 Spring Symposium
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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