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## Content structure

### Inventory

`subglacial_lake_event_inventory_37locations.gpkg`: GeoPackage file in the NSIDC Sea Ice Polar Stereographic North projection (EPSG:3413) showing the locations of 37 active lakes. The attribute field `no` corresponds to the no. of the lake presented in the paper. (See the Conversion table below.)

### Workflows

`[LocationName]/analysis*.ipynb`: Workflow for each [LocationName] (see conversion table below). These Jupyter notebooks start by downloading ArcticDEM and ICESat-2 data and end with the visualization of the lake elevation change. To execute `analysis*.ipynb`, one needs the following auxiliary files which are included in the data set:

- `ArcticDEM_Strip_Index_s2s041_*.gpkg`: Subset of the ArcticDEM strip index, containing the strip outlines within a single RGI region.
- `RGI2000-v7.0-G-*.zip`: RGI 7.0 glacier outlines in a single RGI region. 
- `[LocationName]/refgeo-[LocationName].gpkg`: A rectangle extent at the lake area, defining where to process the data.
- `[LocationName]/[LocationName]-off-ice-exclusion.gpkg`: Polygons that indicate non-stable ground. ICESat-2 points falling within the polygons are not used for aligning the DEMs.

#### Conversion table between location name and lake number 

|  Lake number   |   Location name        |
| -------------- | ---------------------- |
| 1              | MilneTerminus          |
| 2              | Milne                  |
| 3-a            | MilneCentral (left)    |
| 3-b            | MilneCentral (top)     |
| 3-c            | MilneCentral (right)   |
| 4-a            | OttoN (bottom)         |
| 4-b            | OttoN (top)            |
| 5              | IcebergE               |
| 6              | AgassizSWMinor1        |
| 7              | TaggartLake            |
| 8              | MittieNE               |
| 9              | YelvertonNW            |
| 10             | UnnamedFW              |
| 11             | UnnamedHSE             |
| 12             | Antoinette             |
| 13             | AgassizSWMinor2        |
| 14             | MittieMain             |
| 15             | ClydeRiverSW           |
| 16             | PennyN                 |
| 17             | PennyW                 |
| 18             | SvenHedin              |
| 19             | MittieMinor            |
| 20             | OttoNW                 |
| 21             | Otto                   |
| 22             | Disraeli               |
| 23             | UnnamedF               |
| 24             | Airdrop                |
| 25             | LakeToubergE           |
| 26             | GoodFriday (top)       |
| 27             | GoodFriday (bottom)    |
| 28             | Dlberville             |
| 29             | AgassizSWMain (top)    |
| 30             | AgassizSWMain (bottom) |
| 31             | JolliffeNArm           |
| 32             | MittieNW               |
| 33             | BylotNE                |
| 34             | ClydeRiverW            |

### Results

1. `[LocationName]/[LocationName]_15m_hydroevent-evmd-bitmask_[Suffix].tif`: Main results for each glacier. Different suffixes mean: 

   - `slope`: dh/dt of the linear model; $a_1$ in Eq. (1)
   - `duration`: total length of $t$ of the linear model
   - `dh`: maximum short-term dh of the sigmoid model; see Eq. (4)
   - `t`: timing of the maximum short-term dh of sigmoid model
   - `gp-dh`: maximum short-term dh of the GP model
   - `gp-t`: timing of the maximum short-term dh of the GP model

2. `[LocationName]/[LocationName]_15m_hydroevent-evmd-bitmask_viz*.png`: Visualization of the results.
3. `[LocationName]/[LocationName]_15m_median_topo.tif` Median topography of all the available DEM strips.
4. `[LocationName]/deminput_processed.csv`: List of the ArcticDEM strip DEMs used in the analysis. The third column represents the 1-sigma uncertainty in m.
5. `[LocationName]/ref_elevs.csv`: reference elevations extracted from the ICESat-2 ATL-6 data; for DEm alignment. 
6. `[LocationName]/refgeo-[LocationName]_15m.tif`: Reference grid geometry. All the resulting geotiffs have the same image extent and size as this image.