| # Rainshift | |
| Important note: The input precipitation (which is in meter) is in different units than the output precipitation (which is in millimeter), so they differ by a factor of 1000. | |
| More infos can be found in our preprint: https://arxiv.org/pdf/2507.04930? | |
| ## Dataset description | |
| The RainShift dataset builds on three different data products: ERA5 reanalysis, IMERG satellite observations, and static features like land-sea mask and orography. | |
| ### Input Data | |
| #### ERA5 | |
| ERA5 is the fifth-generation atmospheric reanalysis product of the European Center for Medium-Range Weather Forecasts (ECMWF). Reanalysis data are the result of combining historical observations with Earth system models to obtain global estimates of the observed climate. | |
| It provides hourly global data at 0.25degx0.25deg resolution (approximately 25km per pixel in mid-latitudes) on a regular latitude-longitude grid and spans years from 1950 to the present. For compatibility with IMERG, we use data from 2001 onward. | |
| We select nine input variables, including among others different precipitation types, atmospherics water content, and winds, following \citet{Harris2022AGD} and domain-specific knowledge, motivated by the ecPoint model. | |
| - Total precipitation (tp) | |
| - Convective precipitation (cp) | |
| - Convective potential energy (cape) | |
| - Total water content (twc) | |
| - Total liquid water content (tlwc) | |
| - Surface pressure (sp) | |
| - Top-of-the-atmosphere incident solar radiation (tisr) | |
| - eastward component of horizontal wind velocities at 700 hPa (u) | |
| - northward component of horizontal wind velocities at 700 hPa (v) | |
| #### Geographic Features | |
| To complement ERA5 inputs, we include high-resolution static geographic features at 0.1deg resolution: (i) A land-sea mask indicating the land fraction per pixel, and (ii) an elevation map (geopotential height at surface). | |
| ### Target Data - IMERG | |
| The Integrated Multi-satellite Retrievals for GPM (IMERG) is a product of NASA’s Global Precipitation Measurement (GPM) mission. IMERG provides precipitation estimates based on the GPM satellite constellation and additional observations like gauge data. IMERG has full coverage between 60deg N and 60deg S at 0.1deg resolution (about 10km per pixel), like ERA5 on a regular latitude-longitude grid. We use the IMERG V07 Final Run product , averaging its half-hourly data to hourly to match ERA5’s temporal resolution. Data was accessed via NASA Goddard’s GES DISC. | |
| Leveraging global satellite data as a target provides ground truth in the Global South, enabling model evaluation in regions with limited observational data. By using a globally consistent product, RainShift isolates the challenge of regional generalization from potential discrepancies between data products, offering a clean and controlled test case. | |
| ## Dataset instructions | |
| Below you will find instructions for the `rainshift_dataset_utils.py` script. | |
| It has been build to help setup the dataset. | |
| ### Requirements | |
| In the environment of your choice, install the script requirements using the following command: | |
| ```bash | |
| pip install -r requirements.txt | |
| ``` | |
| ### Script use | |
| The script has been build using typer. | |
| It contains 3 commands: | |
| * `download`: To download the dataset to a folder of your choice | |
| * `validate`: To validate the zip files after they've been downloaded | |
| * `unzip`: To unzip the files in a way to preserve dataset folder structure | |
| Use the following command to interact with the script: | |
| ```bash | |
| # General script help | |
| python3 rainshift_dataset_utils.py --help | |
| # download command help | |
| python3 rainshift_dataset_utils.py download --help | |
| # validate command help | |
| python3 rainshift_dataset_utils.py validate --help | |
| # unzip command help | |
| python3 rainshift_dataset_utils.py unzip --help | |
| ``` | |
| The use of the `unzip` command is necessary, as the `zarr` arrays are zipped for storage on HuggingFace. | |
| #### Download | |
| Before downloading, be sure to create the directory where you want to download the dataset. | |
| The `download` command is just a utility wrapper around the HuggingFace python library. | |
| You can also just use this library directly, like so, to download the full dataset : | |
| ```python | |
| from huggingface_hub import HfApi | |
| api = HfApi() | |
| api.snapshot_download(repo_id="RainShift/rainshift", repo_type="dataset", local_dir="<PATH_TO_DIRECTORY>") | |
| ``` |