japanese-climate-calculation

日本語版のREADMEはこちら (Japanese version)

Full documentation

_{Data source: National Land Numerical Information Download Site, Ministry of Land, Infrastructure, Transport and Tourism, Japan.}

A reproducible R + Quarto project for processing climate mesh data in Japan and deriving additional climate indicators such as Potential Evapotranspiration (PET) and Aridity Index.

Overview

This repository documents a workflow based on:

• Japan Meteorological Agency: Mesh Climatology 2020
• MLIT National Land Numerical Information: Average Value Mesh Data

Main outputs include:

• Cleaned climate mesh dataset
• PET (Thornthwaite method)
• Aridity Index (Precipitation / PET)
• Utility function to retrieve nearest climate values from arbitrary coordinates
• Example map visualizations for Japan

Documentation (GitHub Pages)

The full documentation is available at:

• https://maple60.github.io/japanese-climate-calculation/

• English-first documentation is published from docs/.

• Each English page includes a link to the corresponding Japanese page.

The site is served from /docs on the default branch.

Project structure

• index.qmd: English landing page
• index_ja.qmd: Japanese landing page
• notebooks/*.qmd: English chapters
• notebooks/*_ja.qmd: Japanese chapters
• R/get_nearest_climate_value.R: nearest-neighbor utility function
• _quarto.yml: book/site configuration

Setup

1. Clone repository

git clone <your-repo-url>
cd japanese-climate-calculation

2. Restore R environment

renv::restore()

3. Set data directory

Set PROJECT_DATA_DIR in .Renviron (example):

PROJECT_DATA_DIR=/path/to/your/data/root

Build documentation

Render the Quarto book:

quarto render

Generated files are written to docs/.

Data and license notes

This repository does not redistribute source datasets. Please download required files from official sources and follow their terms of use.

• MLIT NLNI terms of use: https://nlftp.mlit.go.jp/ksj/other/agreement.html

Citation and attribution

When using derivatives from NLNI datasets, include required attribution per provider terms.

Language policy

• Source comments and core documentation are maintained in English.
• Japanese companion pages are available for accessibility and continuity.

Contributing

Issues and pull requests are welcome. Please keep code comments and error messages in English.

License

Code in this repository is licensed under the MIT License.

Documentation, text, and original figures are licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0), unless otherwise noted.

Source climate and geospatial datasets are not redistributed in this repository and are not covered by these licenses. Please obtain the original datasets from the official providers and follow their terms of use.