MOD10A2 是 Terra 衛星上 MODIS 的積雪資料集。
資料集會以 500 公尺的解析度，回報八天期間內的最大積雪範圍。
選擇八天的合成期，是因為這是 Terra 和 Aqua 平台確切的地面軌跡重複週期。八天以上的積雪涵蓋範圍會對應至一個 SDS 中的最大積雪範圍，以及另一個 SDS 中的觀測時間順序。八天週期從年初第一天開始，並延伸至下一年。產品可使用兩到八天的輸入內容製作而成。由於各種原因，輸入資料可能不一定有八天，因此使用者應檢查屬性，判斷取得觀察資料的日期。
Hall, D. K. V. V. Salomonson 和 G. A. Riggs。2016 年。MODIS/Terra
Snow Cover Daily L3 Global 500m Grid。第 6 版。美國科羅拉多州波爾得：NASA National Snow and Ice Data Center Distributed Active Archive Center。
[null,null,[],[[["\u003cp\u003eThe MOD10A2 dataset provides information on snow cover, collected by the MODIS sensor on the Terra satellite, spanning from February 18, 2000, to January 25, 2025.\u003c/p\u003e\n"],["\u003cp\u003eThis dataset reports the maximum snow cover extent over eight-day periods at a 500-meter resolution, with data provided by NASA NSIDC DAAC at CIRES.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset includes the maximum snow extent observed over eight days, and a snow chronology bitmask, both of which use specific value ranges to represent no snow, cloud cover, or snow.\u003c/p\u003e\n"],["\u003cp\u003eThe data is collected daily, and the eight day collection period is chosen to match the exact ground track of the Terra and Aqua platforms.\u003c/p\u003e\n"],["\u003cp\u003eUsers can access and analyze the dataset using Google Earth Engine, which is free for research, education, and nonprofit purposes, and can be registered to gain access.\u003c/p\u003e\n"]]],[],null,["# MOD10A2.061 Terra Snow Cover 8-Day L3 Global 500m\n\nDataset Availability\n: 2000-02-18T00:00:00Z--2025-08-05T00:00:00Z\n\nDataset Provider\n:\n\n\n [NASA NSIDC DAAC at CIRES](https://doi.org/10.5067/MODIS/MOD10A2.061)\n\nCadence\n: 1 Day\n\nTags\n:\n[cryosphere](/earth-engine/datasets/tags/cryosphere) [daily](/earth-engine/datasets/tags/daily) [geophysical](/earth-engine/datasets/tags/geophysical) [global](/earth-engine/datasets/tags/global) [modis](/earth-engine/datasets/tags/modis) [nasa](/earth-engine/datasets/tags/nasa) [nsidc](/earth-engine/datasets/tags/nsidc) [snow](/earth-engine/datasets/tags/snow) [terra](/earth-engine/datasets/tags/terra) \n\n#### Description\n\nMOD10A2 is a snow cover dataset from the MODIS on the Terra satellite.\nThe dataset reports the maximum snow cover extent during an eight-day\nperiod at the resolution of 500 m.\n\nAn eight-day compositing period was chosen because that is the exact ground\ntrack repeat period of the Terra and Aqua platforms. Snow cover over eight\ndays is mapped as maximum snow extent in one SDS and as a chronology of\nobservations in the other SDS. Eight-day periods begin on the first day of\nthe year and extend into the next year. The product can be produced with\ntwo to eight days of input. There may not always be eight days of input,\nbecause of various reasons, so the user should check the attributes to\ndetermine on what days observations were obtained.\n\n- [General documentation](https://doi.org/10.5067/MODIS/MOD10A2.061)\n- [User's Guide](https://modis-snow-ice.gsfc.nasa.gov/uploads/snow_user_guide_C6.1_final_revised_april.pdf),\n\n### Bands\n\n\n**Pixel Size**\n\n500 meters\n\n**Bands**\n\n| Name | Min | Max | Pixel Size | Description |\n|------------------------|-----|-----|------------|-----------------------------------------------------------------------------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|\n| `Maximum_Snow_Extent` | 0 | 255 | meters | Maximum snow extent observed over an eight-day period. |\n| `Eight_Day_Snow_Cover` | | | meters | Snow chronology bit flags for each day in the eight-day observation period. |\n| Bitmask for Eight_Day_Snow_Cover - Bit 0: day 1 - Bit 1: day 2 - Bit 2: day 3 - Bit 3: day 4 - Bit 4: day 5 - Bit 5: day 6 - Bit 6: day 7 - Bit 7: day 8 ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n\n**Maximum_Snow_Extent Class Table**\n\n| Value | Color | Description |\n|-------|-------|--------------------|\n| 0 | None | Missing data |\n| 1 | None | No decision |\n| 11 | None | Night |\n| 25 | None | No snow |\n| 37 | None | Lake |\n| 39 | None | Ocean |\n| 50 | None | Cloud |\n| 100 | None | Lake ice |\n| 200 | None | Snow |\n| 254 | None | Detector saturated |\n\n### Terms of Use\n\n**Terms of Use**\n\nYou may download and use photographs, imagery, or text\nfrom the NSIDC web site, unless limitations for its use are specifically\nstated. For more information on usage and citing NSIDC datasets,\nplease visit the\n[NSIDC 'Use and Copyright' page](https://nsidc.org/about/data-use-and-copyright).\n\n### Citations\n\nCitations:\n\n- Hall, D. K., V. V. Salomonson, and G. A. Riggs. 2016. MODIS/Terra\n Snow Cover Daily L3 Global 500m Grid. Version 6. Boulder, Colorado\n USA: NASA National Snow and Ice Data Center Distributed Active\n Archive Center.\n\n### DOIs\n\n- \u003chttps://doi.org/10.5067/MODIS/MOD10A1.061\u003e\n- \u003chttps://doi.org/10.5067/MODIS/MOD10A2.061\u003e\n\n### Explore with Earth Engine\n\n| **Important:** Earth Engine is a platform for petabyte-scale scientific analysis and visualization of geospatial datasets, both for public benefit and for business and government users. Earth Engine is free to use for research, education, and nonprofit use. To get started, please [register for Earth Engine access.](https://console.cloud.google.com/earth-engine)\n\n### Code Editor (JavaScript)\n\n```javascript\nvar dataset = ee.ImageCollection('MODIS/061/MOD10A2')\n .filter(ee.Filter.date('2023-01-01', '2023-12-01'))\n .select('Maximum_Snow_Extent');\n\nvar visualization = {\n min: 50.0,\n max: 200.0,\n palette: [\n '000000',\n '0dffff',\n '0524ff',\n 'ffffff'\n ]\n};\n\n\nMap.setCenter(-3.69, 65.99, 4);\n\nMap.addLayer(dataset.mean(), visualization, 'Maximum_Snow_Extent');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/MODIS/MODIS_061_MOD10A2) \n[MOD10A2.061 Terra Snow Cover 8-Day L3 Global 500m](/earth-engine/datasets/catalog/MODIS_061_MOD10A2) \nMOD10A2 is a snow cover dataset from the MODIS on the Terra satellite. The dataset reports the maximum snow cover extent during an eight-day period at the resolution of 500 m. An eight-day compositing period was chosen because that is the exact ground track repeat period of the Terra and ... \nMODIS/061/MOD10A2, cryosphere,daily,geophysical,global,modis,nasa,nsidc,snow,terra \n2000-02-18T00:00:00Z/2025-08-05T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.5067/MODIS/MOD10A2.061](https://doi.org/https://doi.org/10.5067/MODIS/MOD10A2.061)\n- [https://doi.org/10.5067/MODIS/MOD10A2.061](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MOD10A2)"]]
