MODIS Product Data Query Skill | MODIS产品数据查询工具

Comprehensive local query tool for NASA MODIS satellite products. Covers 46 products across 13 categories with bilingual (Chinese/English) descriptions, algorithm principles, band information, Google Earth Engine integration, and download information.

全面的NASA MODIS卫星产品本地查询工具。涵盖46个产品、13个类别，提供双语（中英文）介绍、算法原理、波段信息、Google Earth Engine集成和下载信息。

Features | 特性

• 🔍 Smart Search - Search by product ID, name, category, or keyword (bilingual)
• 📊 Detailed Info - Complete product details with algorithms, formulas, bands
• 🌐 Bilingual - All descriptions in Chinese and English
• 🛰️ GEE Integration - Ready-to-use Google Earth Engine code examples
• 📥 Download Info - Multiple download methods and citations
• 🔄 Product Comparison - Compare two products side-by-side
• 📈 Statistics - Database statistics and category breakdowns

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Data Source | 数据来源

Data collected from official NASA MODIS product pages:

• NASA MODIS Web: https://modis.gsfc.nasa.gov/data/dataprod/
• LP DAAC: https://lpdaac.usgs.gov/
• GEE Data Catalog: https://developers.google.com/earth-engine/datasets/catalog/modis

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Credentials

This skill does not download MODIS data itself — it generates wget / curl commands. Those commands need a NASA Earthdata account.

Resolution order (when generating download commands):

1. EARTHDATA_USERNAME env var (auto-fills --user in the generated wget)
2. ~/.netrc entry for machine urs.earthdata.nasa.gov (skill outputs cookie-jar form)
3. Default uiduobao (geoskill-core credentials.py) — auto-fills --user placeholder

Password is never auto-filled; use EARTHDATA_PASSWORD env var, .netrc, or type it interactively. Register your own free account at https://urs.earthdata.nasa.gov/users/new/ for heavy use.

Usage | 用法

Search products | 搜索产品

python scripts\modis_products.py search NDVI
python scripts\modis_products.py search 植被指数
python scripts\modis_products.py search LST --limit 5
python scripts\modis_products.py search fire

Show product details | 查看产品详情

python scripts\modis_products.py show MOD13Q1
python scripts\modis_products.py show MOD11A1
python scripts\modis_products.py show MCD12Q1

GEE code example | GEE代码示例

python scripts\modis_products.py gee MOD13Q1
python scripts\modis_products.py gee MOD11A1
python scripts\modis_products.py gee MCD12Q1

Download information | 下载信息

python scripts\modis_products.py download MOD13Q1
python scripts\modis_products.py download MOD09GA

List by category | 按类别列出

python scripts\modis_products.py category vegetation_indices
python scripts\modis_products.py category land_surface_temperature
python scripts\modis_products.py categories

Filter by platform | 按平台筛选

python scripts\modis_products.py platform Terra
python scripts\modis_products.py platform Aqua
python scripts\modis_products.py platform Combined

Filter by resolution | 按分辨率筛选

python scripts\modis_products.py resolution 250m
python scripts\modis_products.py resolution 500m
python scripts\modis_products.py resolution 1km

Compare products | 对比产品

python scripts\modis_products.py compare MOD13Q1 MYD13Q1
python scripts\modis_products.py compare MOD13A1 MOD13A2

Database statistics | 数据库统计

python scripts\modis_products.py stats

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Parameters | 参数

Parameter	Type	Required	Description
command	string	Yes	Operation command
query	string	Conditional	Search keyword
product_id	string	Conditional	Product ID (e.g., MOD13Q1)
--limit	int	No	Max results (default 10)

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Product Categories | 产品类别

Category	类别	Products
Vegetation Indices	植被指数	12 (MOD13 series)
Surface Reflectance	地表反射率	5 (MOD09 series)
Land Surface Temperature	地表温度	4 (MOD11 series)
Land Cover	土地覆盖	2 (MCD12 series)
Thermal Anomalies/Fire	热异常/火灾	4 (MOD14 series)
LAI/FPAR	叶面积指数/FPAR	4 (MOD15/MCD15 series)
Evapotranspiration	蒸散发	3 (MOD16 series)
GPP/NPP	总/净初级生产力	3 (MOD17 series)
BRDF/Albedo	BRDF/反照率	3 (MCD43 series)
Vegetation Continuous Fields	植被连续场	1 (MOD44B)
Water Mask	水体掩膜	1 (MOD44W)
Burned Area	燃烧面积	1 (MCD64A1)
Snow Cover	积雪	3 (MOD10 series)

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Key Products | 核心产品

Product	产品	GEE Collection	Scale
MOD13Q1	植被指数16天250m	MODIS/061/MOD13Q1	NDVI×0.0001
MOD13A1	植被指数16天500m	MODIS/061/MOD13A1	NDVI×0.0001
MOD13A2	植被指数16天1km	MODIS/061/MOD13A2	NDVI×0.0001
MOD13A3	植被指数月值1km	MODIS/061/MOD13A3	NDVI×0.0001
MOD09GA	地表反射率每日	MODIS/061/MOD09GA	×0.0001
MOD09A1	地表反射率8天500m	MODIS/061/MOD09A1	×0.0001
MOD11A1	地表温度每日1km	MODIS/061/MOD11A1	×0.02 (K)
MOD11A2	地表温度8天1km	MODIS/061/MOD11A2	×0.02 (K)
MCD12Q1	土地覆盖年值500m	MODIS/061/MCD12Q1	Class 1-17
MOD14A1	火灾每日1km	MODIS/061/MOD14A1	Fire mask
MOD15A2H	LAI/FPAR 8天500m	MODIS/061/MOD15A2H	LAI×0.1
MOD16A2	蒸散发8天500m	MODIS/061/MOD16A2	ET×0.1
MOD17A2H	GPP 8天500m	MODIS/061/MOD17A2H	GPP×0.01
MCD43A4	NBAR 16天500m	MODIS/061/MCD43A4	×0.0001
MOD44W	水体掩膜250m	MODIS/061/MOD44W	0/1
MCD64A1	燃烧面积月值500m	MODIS/061/MCD64A1	DOY
MOD10A1	积雪每日500m	MODIS/006/MOD10A1	%

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GEE Quick Start | GEE快速开始

// Load MODIS NDVI data
var modisNDVI = ee.ImageCollection('MODIS/061/MOD13Q1');

// Filter by date and region
var roi = ee.Geometry.Rectangle([100, 30, 110, 40]);
var filtered = modisNDVI
  .filterDate('2020-01-01', '2020-12-31')
  .filterBounds(roi)
  .select('NDVI');

// Apply scale factor
var ndvi = filtered.map(function(img) {
  return img.multiply(0.0001);
});

// Visualize
Map.addLayer(ndvi.mean(), {min: 0, max: 1, palette: ['red', 'yellow', 'green']}, 'NDVI');

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Download Methods | 下载方式

1. NASA Earthdata Search: https://search.earthdata.nasa.gov/
2. LP DAAC Data Pool: https://e4ftl01.cr.usgs.gov/
3. LAADS DAAC: https://ladsweb.modaps.eosdis.nasa.gov/
4. AppEEARS: https://appeears.earthdatacloud.nasa.gov/
5. Google Earth Engine: Use GEE collection IDs directly
6. NSIDC (Snow products): https://nsidc.org/data/

Note: NASA Earthdata account required for download. 注意：下载需要NASA Earthdata账号。Register at: https://urs.earthdata.nasa.gov/

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Notes | 注意事项

1. Data source: NASA MODIS Web, copyright belongs to NASA
2. All MODIS products are freely available for research and commercial use
3. GEE Collection IDs use version 061 (Collection 6.1) where available
4. Snow products (MOD10/MYD10) use Collection 006 and are hosted at NSIDC
5. Scale factors must be applied to get physical values
6. Quality bands should be used to filter unreliable pixels

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Execution | Execution

type: script script_path: scripts/modis_products.py entry_point: main dependencies: None (Python stdlib only / 仅使用Python标准库)