CALFIN

Calving Front Machine. Automated detection of glacial terminus positions, using neural networks.

Introduction

This is the official codebase for Calving Front Machine (CALFIN): an Automated Deep Learning Glacial Terminus Extraction Method [1]. We provide an automated pipeline using a modified DeepLabV3+ with Xception neural network. The mean distance error is 2.25 pixels (86.76 meters) from the true front on a diverse set of 162 validation images.

The method is used to generate the CALFIN dataset, consisting of 22,678 total calving fronts spanning 66 Greenlandic basins, from Sept. 1972 - June 2019. The CALFIN dataset can be downloaded at DataDryad [2].

Running CALFIN

The CALFIN codebase allows for execution of the automated pipeline on new data, as well as the training of the CALFIN neural network on new data. To continue, select the desired section(s) from the table of contents below.

Installation

1. Download the repository with git clone https://github.com/daniel-cheng/CALFIN.
2. Install dependencies using Anaconda package manager with conda env create -f training/dependencies/environment_<os>_cfm.yml, selecting your OS file from training/dependencies, or base otherwise. If performing Shapefile postprocessing, also install environment_<os>_rasterio.yml similarly in a second environment, to avoid package conflicts.
3. Download the trained network weights from the v1.0.0 Release and extract them to training/cfm_weights_patched_dual_wide_x65_224_e17_iou0.5236.h5.
4. Run CALFIN in a Python console such as Spyder, or on the command line by prepending python before the path to each script. Modify script parameters as required.

Preprocessing

1. Create a square Shapefile polygon in the projection of your source imagery in preprocessing/domains.
2. Subset all source images, by loading them in QGIS with bulk_add_rasters and executing the bulk_subsetter.
3. Optionally, enhance the subsets, either using the HDR/Shadows & Highlights Adobe Photoshop CS6 presets, or other contrast enhancements.
4. Use the bulk_layerer to combine grayscale subsets into RGB input images in processing/landsat_raw_processed.

Processing

1. Execute run_production.py. Results will be generated in outputs/production.

Postprocessing

1. Optionally, verify the results of outputs/production/quality_assurance/<domain>, and copy any *overlay_front.png files that are incorrect to the corresponding outputs/production/quality_assurance_bad/<domain> folder to eliminate it from the final output.
2. Finally, switch to the rasterio environment to avoid pacakge conflicts, and run the postprocessing/bulk_shapefile_polygonizer.py, then the postprocessing/bulk_shapefile_consolidator.py to create the final outputs in outputs/upload_production/v1.0/level-1_shapefiles-domain-termini.

Training

1. Optionally, create new training data after running Preprocessing by creating the corresponding masks for each image (See training/data/train) and fjord boundaries for each domain (See below section) in an image editing program.
2. Prepare preprocessed data by running training/data_cfm_patched_dual.py. This will generate optimized validation/training processing during training.
3. Optionally, modify the data augmentation routines in training/aug_generators_dual.py, or the neural network architecture in training/model_cfm_dual_wide_x65.py.
4. Run training/train_cfm_v11_224_deeplabv3-xception_patched-256-16.py.

Testing

1. To reproduce the validation results in our study [1], execute postprocessing/run_calfin_on_calfin.py, postprocessing/run_calfin_on_mohajerani.py, postprocessing/run_calfin_on_zhang.py, and postprocessing/run_calfin_on_baumhoer.py.

Running CALFIN on New Domains

If you plan to use CALFIN on a domain outside of the existing set, be familiar with the training set and the set of conditions CALFIN can handle (see [1]). CALFIN was trained using Landsat (optical) and Sentinel-1 (SAR) data. The training set includes 1600+ Greenlandic glaciers and 200+ Antarctic glaciers/ice shelves. CALFIN can handle ice tongues, branching, Landsat 7 Scanline Corrector Errors, sea ice, shadows, and light cloud cover.

CALFIN requires a fjord boundaries mask in order to function - these must be created manually, then geolocated as a GeoTiff to enable Shapefile outputs. Optionally, create fjord boundary overrides to enforce static fronts not captured in the fjrod boundary mask or in CALFIN output. See also training/data/fjord_boundaries, training/data/fjord_boundaries_tif, and preprocessing/bulk_png_to_geotiff.py.

ISSM integration (in development)

CALFIN can be executed from the Ice-Sheet and Sea-level System Model.

Preprocessing

First, we perform Subsetting, which is the finding of the tiles within a larger image that correspond to an area of interest.

1. Download GeoTIFF images from EarthExplorer.gov
   1. Select a location on the map
   2. Select a time frame
   3. Select DataSets and select collections such as Landsat > Landsat Collection 1 > Landsat Collection 1 Level-1 > Landsat 8
   4. Viewing the results and download all relevant images via the download button and selecting the LandsatLook Images with Geographic Reference data product. Optionally, use the Bulk Download Assistant to download them automatically.
2. Unzip the RGB .tif images and subset them using QGIS (TODO).
3. Place output .tifs to process in /home/ubuntu/Repos/CALFIN/processing/testing

Processing

Then, we can run CALFIN to extract coastlines/calving fronts from the subsets. 4. Open Matlab and add ISSM to the path by executing addpath(genpath('/home/ubuntu/Repos/issm/issm/trunk-jpl-working/src/m')). 5. Create a calfin object by executing cf = calfin();. 6. Solve for calving fronts/coastlines using CALFIN by executing cf.solve(). 7. View the results view the figures or via the folder /home/ubuntu/Repos/CALFIN/outputs/testing/quality_assurance.

Citation

If you find this code helpful, please cite as below:

@article{ChengHLMWVR2020,
	title={Calving Front Machine (CALFIN): Glacial Termini Dataset and 
			Automated Deep Learning Extraction Method for Greenland, 1972-2019},
	author={Daniel Cheng and Wayne Hayes and Eric Larour and Yara Mohajerani and 
			Michael Wood and Isabella Velicogna and Eric Rignot},
	journal={The Cryosphere Discussions},
	url = {https://tc.copernicus.org/preprints/tc-2020-231/},
	doi = {10.5194/tc-2020-231},
	year={2020}
}

@dataset{ChengHL2020,
	title={CALFIN: Calving Front Dataset for East/West Greenland, 1972-2019},
	author={Daniel Cheng and Wayne Hayes and Eric Larour},
	url={https://datadryad.org/stash/dataset/doi:10.7280/D1FH5D},
	doi={10.7280/D1FH5D},
	year={2020}
}

References

[1] Cheng, D., Hayes, W., Larour, E., Mohajerani, Y., Wood, M., Velicogna, I. and Rignot, E.: Calving Front Machine (CALFIN): Glacial Termini Dataset and Automated Deep Learning Extraction Method for Greenland, 1972-2019, The Cryosphere Discussions, 1–17, https://doi.org/10.5194/tc-2020-231, 2020.

[2] Cheng, D., Hayes, W. and Larour, E.: CALFIN: Calving front dataset for East/West Greenland, 1972-2019, https://doi.org/10.7280/D1FH5D, 2020.

Acknowledgements

This work was conducted as a collaboration between NASA’s Jet Propulsion Laboratory and the University of California, Irvine.

The CALFIN neural network architecture implementation is derived from Emil Zakirov’s Deeplabv3+ Xception codebase.

We acknowledge the USGS for providing Landsat-1-8 images, the ESA for their Sentinel-1 images, as well as the ESA-CCI, PROMICE, and MEaSUREs programs for providing calving front data used in this study.

Contact

For questions, contact dlcheng@uci.edu.