🌍 era5py

Download, post-process and analyse ERA-5 reanalysis data via the CDS API.

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🚀 Usage

python run_era5.py -o download -c settings_name.yml

Flag	Values	Description
-o	download, process, visualize, stats	Operation to run
-c	e.g. settings_bolivia.yml	Settings file inside etc/

📁 Files are saved as era5_raw_<year>_<variable>_<name>.nc inside output_dir.

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🌡️ Variables supported

Short name	ERA-5 variable
t2m	2 m temperature
d2m	2 m dewpoint temperature
tp	Total precipitation
u10 / v10	10 m U/V wind components
u100 / v100	100 m U/V wind components
wind at target heights	Reconstructed via log-wind profile

✨ Derived outputs: temperature in °C, precipitation in mm, specific humidity (g kg⁻¹), wind speed at 10 / 30 / 50 m.

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📂 Project layout

era5py/
├── run_era5.py              # 🔑 Entry point
├── etc/
│   └── settings_name.yml   # ⚙️  User configuration files
├── data/
│   └── name/               # 📥 Downloaded NetCDF files
├── results/
│   └── name/               # 📊 Processed CSVs and figures
├── requirements.txt
└── src/era5py/
    ├── __init__.py
    ├── download_era5.py     # ⬇️  Download functions
    ├── post_processing.py   # 📈 Statistics
    └── process_era5.py      # 🔄 Processing and visualisation

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⚙️ Requirements

Python 3.12 and:

pip install -r requirements.txt

🔑 CDS API key

1. Register at https://cds.climate.copernicus.eu
2. Follow the how-to-api guide to create ~/.cdsapirc:

url: https://cds.climate.copernicus.eu/api
key: <YOUR_API_KEY>

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🗂️ Configuration

Create a settings file inside etc/ (use etc/settings_example.yml as a template):

year_start: 2020
year_end:   2021
name:       bolivia

variables:
  - 2m_temperature
  - total_precipitation

mode: area            # "point" or "area"

lat:  -16.5           # used when mode = point
lon:  -68.15

area:                 # used when mode = area
  north:  -8.0
  west:  -70.0
  south: -24.0
  east:  -57.0