SWECAST (Snow Water Equivalent Forecasting)

• Micromamba environment
  • PyPI TensorFlow
    • Creating a new micromamba environment
    • Running the example
• Installation
• Authentication
• Quick start
• Core concepts
  • Manifest
• Main functions
  • build_stacks(manifest, output_dir)
  • build_swe_stacks(manifest, output_dir)
  • fill_stacks(stacks)
  • fetch_stations(...)
  • stations_to_csv(...)
• Output
• Development notes

Micromamba environment

PyPI TensorFlow

Creating a new micromamba environment

# install micromamba
curl -L https://micro.mamba.pm/install.sh | env \
  BIN_FOLDER="$HOME/local/bin" \
  PREFIX_LOCATION="$HOME/opt/micromamba" \
  sh

# create an alias
echo "alias mm=micromamba" >> ~/.bashrc

# source micromamba
. ~/.bashrc

mkdir -p ~/work/projects/swecast
cd ~/work/projects/swecast
git clone git@github.com:hydrocslab/swecast.git

# the latest tensorflow supports python 3.13
mm create -n swecast -y python=3.13
mm activate swecast

# add cuda lib paths to LD_LIBRARY_PATH automatically when activating the
# environment
mkdir -p $CONDA_PREFIX/etc/conda/activate.d
cat > $CONDA_PREFIX/etc/conda/activate.d/tensorflow-cuda.sh <<'EOF'
export _OLD_LD_LIBRARY_PATH="$LD_LIBRARY_PATH"

export LD_LIBRARY_PATH="$(python - <<'PY'
import site
from pathlib import Path

for sp in site.getsitepackages():
    nvidia = Path(sp) / "nvidia"
    if nvidia.exists():
        for lib in nvidia.glob("*/lib"):
            print(lib, end=":")
PY
)$LD_LIBRARY_PATH"
EOF

mkdir -p $CONDA_PREFIX/etc/conda/deactivate.d
cat > $CONDA_PREFIX/etc/conda/deactivate.d/tensorflow-cuda.sh <<'EOF'
export LD_LIBRARY_PATH="$_OLD_LD_LIBRARY_PATH"
EOF

pip install tensorflow[and-cuda] rasterio shapely xarray scipy netCDF4 matplotlib rioxarray tomli_w

. $CONDA_PREFIX/etc/conda/activate.d/tensorflow-cuda.sh

# make sure GPU is recognized
python -c "import tensorflow as tf; print(tf.config.list_physical_devices('GPU'))"

mm deactivate

Running the example

mm activate swecast

cd ~/work/projects/swecast
mkdir -p runs/example
cd runs/example
python ../../swecast/example.py

mm deactivate

Installation

For now, install locally:

pip install -e .

This will change once published to PyPI.

Authentication

swecast requires access to external data services. You must set your Earthdata credentials as environment variables before running the module:

export EARTHDATA_USERNAME='your_earthdata_username'
export EARTHDATA_PASSWORD='your_earthdata_password'

Without these, data downloads will fail.

Quick start

import swecast
from datetime import date
from swecast import Manifest, build_stacks, build_swe_stacks
from swecast import fetch_stations, stations_to_csv, fill_stacks

manifest = Manifest(
    start=date(2001, 1, 1),
    end=date(2002, 1, 1),
    bbox=(-121.9, 36.08, -109, 41.98),
)

# Build general data stacks
outputs = build_stacks(manifest, output_dir="./output")

# Build SWE stacks
swe_outputs = build_swe_stacks(manifest, output_dir="./output")

# Gap-fill SWE stacks
fill_stacks(swe_outputs)

Core concepts

Manifest

The Manifest object defines the scope of your data processing job:

• start / end: Date range for the dataset
• bbox: Geographic bounding box (min_lon, min_lat, max_lon, max_lat)

Main functions

build_stacks(manifest, output_dir)

Builds general geospatial data stacks for the given manifest.

build_swe_stacks(manifest, output_dir)

Builds Snow Water Equivalent (SWE) stacks.

fill_stacks(stacks)

Performs gap-filling on SWE stacks to handle missing data.

fetch_stations(...)

Fetches station metadata (usage still evolving).

stations_to_csv(...)

Exports station data to CSV format.

Output

All outputs are written to the specified output_dir. The structure and formats may change as the project evolves.

Development notes

• This project is actively under development
• Interfaces are not yet stable