geoskill-monsoon-analysis

分析季风系统：风场季节反转、季风指数、降水集中度与季风进退日期突变点检测，支持东亚/南亚区域

季风分析 | Monsoon Analysis

This skill diagnoses the monsoon system from wind-field and precipitation time series, producing three core metrics:

• Seasonal wind reversal: computes the angle between winter/summer mean wind directions (close to 180° indicates a complete reversal), and defines the monsoon index MI = mean(u, summer half-year) − mean(u, winter half-year) from the seasonal shear of zonal wind (Webster–Yang type). The East Asian summer monsoon veers southerly (u positive), while the South Asian summer monsoon is southwesterly (u negative).
• Precipitation concentration: the proportion of annual precipitation falling within the monsoon season (concentration) and a normalized seasonality index.
• Monsoon onset/retreat dates: detects onset / peak / retreat change points along the daily cumulative precipitation series.

Supports --region east_asia|south_asia (the two regions differ in monsoon season and prevailing wind direction). Suitable for monsoon climate diagnosis, monsoon onset/withdrawal monitoring, and studies of seasonal precipitation distribution.

Dependencies / 依赖

bash

pip install 'numpy' 'rasterio' 'scipy'

Usage / 使用方法

Basic usage

bash

python geoskill-monsoon-analysis.py --bbox 116.0 39.0 117.0 40.0 [other options]

Example 1 (synthetic data, offline)

bash

python geoskill-monsoon-analysis.py --bbox 116.0 39.0 117.0 40.0 --synthetic --output-dir ./out

Example 2 (bbox only, auto synthetic, East Asia)

bash

python geoskill-monsoon-analysis.py --bbox 110.0 20.0 122.0 40.0 --output-dir ./out

Example 3 (South Asia region)

bash

python geoskill-monsoon-analysis.py --bbox 70.0 8.0 90.0 30.0 --region south_asia --synthetic --output-dir ./out

Example 4 (longer time series)

bash

python geoskill-monsoon-analysis.py --bbox 110.0 20.0 122.0 40.0 --region east_asia --n-dates 36 --output-dir ./out --quiet

Example 5 (real wind-field raster input, u/v interleaved bands)

bash

python geoskill-monsoon-analysis.py --input wind_monthly.tif --region east_asia --output-dir ./out

Output / 输出

File	Format	Description
monsoon_index.tif	GeoTIFF	Monsoon index (seasonal shear of zonal wind) raster
u_wind_seasonal.tif	GeoTIFF	Winter/summer mean zonal wind (2 bands)
monsoon_diagnosis.json	JSON	Diagnostics such as reversal angle, concentration, onset/retreat dates
output-manifest.json	JSON	Run manifest

Data Source / 数据源 / Source

• Real mode: local GeoTIFF (u/v interleaved monthly bands).
• Synthetic mode (--synthetic or bbox-only): generates a seasonally reversing wind field plus concentrated monsoon-season precipitation locally, no network required.

Privacy / 隐私声明 / Privacy

• Runs offline by default; --synthetic mode requires no network at all.
• All processing is performed locally; user data is never uploaded.

License / License

MIT

---

---

name: geoskill-monsoon-analysis description: '分析季风系统：风场季节反转、季风指数、降水集中度与季风进退日期突变点检测，支持东亚/南亚区域'

季风分析 | Monsoon Analysis

本 skill 对风场与降水时序做季风系统诊断，输出三类核心指标：

• 风场季节反转：计算冬/夏平均风向夹角（接近 180° 表示完全反转），并以 纬向风季节剪切定义季风指数 MI = mean(u, 夏半年) − mean(u, 冬半年) （Webster-Yang 型）。东亚夏季风偏南（u 为正），南亚夏季西南风（u 为负）。
• 降水集中度：季风期降水占全年比例（concentration）与归一化季节性指数。
• 季风进退日期：在逐日降水累计序列上检测 onset / peak / retreat 突变点。

支持 --region east_asia|south_asia（两区季风期与主导风向不同）。适用于 季风气候诊断、季风爆发/撤退监测、降水季节分配研究。

依赖

bash

pip install 'numpy' 'rasterio' 'scipy'

使用方法

基本用法

bash

python geoskill-monsoon-analysis.py --bbox 116.0 39.0 117.0 40.0 [其他参数]

示例 1（合成数据，离线）

bash

python geoskill-monsoon-analysis.py --bbox 116.0 39.0 117.0 40.0 --synthetic --output-dir ./out

示例 2（仅给 bbox，自动合成，东亚）

bash

python geoskill-monsoon-analysis.py --bbox 110.0 20.0 122.0 40.0 --output-dir ./out

示例 3（南亚区域）

bash

python geoskill-monsoon-analysis.py --bbox 70.0 8.0 90.0 30.0 --region south_asia --synthetic --output-dir ./out

示例 4（更长时间序列）

bash

python geoskill-monsoon-analysis.py --bbox 110.0 20.0 122.0 40.0 --region east_asia --n-dates 36 --output-dir ./out --quiet

示例 5（真实风场栅格输入，u/v 交替波段）

bash

python geoskill-monsoon-analysis.py --input wind_monthly.tif --region east_asia --output-dir ./out

输出

文件	格式	说明
monsoon_index.tif	GeoTIFF	季风指数（纬向风季节剪切）栅格
u_wind_seasonal.tif	GeoTIFF	夏/冬平均纬向风（2 波段）
monsoon_diagnosis.json	JSON	反转角、集中度、进退日期等诊断
output-manifest.json	JSON	运行清单

数据源 / Source

• 真实模式：本地 GeoTIFF（u/v 交替月波段）。
• 合成模式（--synthetic 或仅 --bbox）：本地生成季节反转风场 + 季风期集中降水，无需网络。

隐私声明 / Privacy

• 默认离线运行，--synthetic 模式完全无网络。
• 所有处理在本地完成，不上传用户数据。

License

MIT