توفّر منتجات MODIS لقياس الانعكاس على السطح تقديرًا لانعكاس الطيف على السطح كما سيتم قياسه على مستوى سطح الأرض في حال عدم وجود تشتت أو امتصاص في الغلاف الجوي.
يتم تصحيح البيانات ذات المستوى المنخفض للغازات الجوية والرذاذ.
يوفر الإصدار 6.1 من MOD09GQ النطاقَين 1 و2 بدقة 250 مترًا في منتج L2G مترابط يومي في إسقاط جيبي، بما في ذلك مراقبة الجودة وخمس طبقات ملاحظة. يُفترض استخدام هذا المنتج
بالتزامن مع MOD09GA حيث يتم تخزين معلومات مهمة حول الجودة وهندسة العرض.
توفّر منتجات MODIS لقياس الانعكاس على السطح تقديرًا لانعكاس الطيف على السطح كما سيتم قياسه على مستوى سطح الأرض في حال عدم وجود تشتت أو امتصاص في الغلاف الجوي. يتم تصحيح البيانات ذات المستوى المنخفض للغازات الجوية والرذاذ. يوفر الإصدار 6.1 من MOD09GQ النطاقَين 1 و2 بدقة تبلغ 250 مترًا …
[null,null,[],[[["\u003cp\u003eMOD09GQ v6.1 provides daily global surface reflectance data at 250m resolution for bands 1 (red) and 2 (near-infrared).\u003c/p\u003e\n"],["\u003cp\u003eThe data is corrected for atmospheric effects, offering an estimate of surface reflectance as measured at ground level.\u003c/p\u003e\n"],["\u003cp\u003eIt includes quality assurance layers and observation information for data reliability assessment.\u003c/p\u003e\n"],["\u003cp\u003eThis product is meant to be used with MOD09GA, which contains important quality and viewing geometry information.\u003c/p\u003e\n"],["\u003cp\u003eMODIS data and products acquired through the LP DAAC have no restrictions on subsequent use, sale, or redistribution.\u003c/p\u003e\n"]]],[],null,["Dataset Availability\n: 2000-02-24T00:00:00Z--2025-08-30T00:00:00Z\n\nDataset Provider\n:\n\n\n [NASA LP DAAC at the USGS EROS Center](https://doi.org/10.5067/MODIS/MOD09GQ.061)\n\nCadence\n: 1 Day\n\nTags\n:\n [daily](/earth-engine/datasets/tags/daily) [global](/earth-engine/datasets/tags/global) [modis](/earth-engine/datasets/tags/modis) [nasa](/earth-engine/datasets/tags/nasa) [satellite-imagery](/earth-engine/datasets/tags/satellite-imagery) [sr](/earth-engine/datasets/tags/sr) [surface-reflectance](/earth-engine/datasets/tags/surface-reflectance) [terra](/earth-engine/datasets/tags/terra) [usgs](/earth-engine/datasets/tags/usgs) \nmod09gq \n\nDescription \nThe MODIS Surface Reflectance products provide an estimate\nof the surface spectral reflectance as it would be measured at\nground level in the absence of atmospheric scattering or absorption.\nLow-level data are corrected for atmospheric gases and aerosols.\nMOD09GQ version 6.1 provides bands 1 and 2 at a 250m resolution in\na daily gridded L2G product in the Sinusoidal projection, including\na QC and five observation layers. This product is meant to be used\nin conjunction with the MOD09GA where important quality and viewing\ngeometry information is stored.\n\nDocumentation:\n\n- [User's Guide](https://lpdaac.usgs.gov/documents/306/MOD09_User_Guide_V6.pdf)\n\n- [Algorithm Theoretical Basis Document (ATBD)](https://lpdaac.usgs.gov/documents/305/MOD09_ATBD.pdf)\n\n- [General Documentation](https://ladsweb.modaps.eosdis.nasa.gov/filespec/MODIS/61/MOD09GQ)\n\nBands\n\n\n**Pixel Size**\n\n250 meters\n\n**Bands**\n\n| Name | Min | Max | Scale | Pixel Size | Wavelength | Description |\n|--------------------|------|-------|--------|------------|------------|---------------------------------------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|\n| `num_observations` | 0 | 127 | | meters | None | Number of observations per 250m pixel |\n| `sur_refl_b01` | -100 | 16000 | 0.0001 | meters | 620-670nm | Surface reflectance band 1 |\n| `sur_refl_b02` | -100 | 16000 | 0.0001 | meters | 841-876nm | Surface reflectance for band 2 |\n| `QC_250m` | | | | meters | None | Surface reflectance quality assurance |\n| Bitmask for QC_250m - Bits 0-1: MODLAND QA bits - 0: Corrected product produced at ideal quality - all bands - 1: Corrected product produced at less than ideal quality - some or all bands - 2: Corrected product not produced due to cloud effects - all bands - 3: Corrected product not produced for other reasons - some or all bands, may be fill value (11) \\[Note that a value of (11) overrides a value of (01)\\] - Bits 2-3: Spare (unused) - 0: N/A - Bits 4-7: Band 1 data quality - 0: Highest quality - 7: Noisy detector - 8: Dead detector, data interpolated in L1B - 9: Solar zenith \\\u003e= 86 degrees - 10: Solar zenith \\\u003e= 85 and \\\u003c 86 degrees - 11: Missing input - 12: Internal constant used in place of climatological data for at least one atmospheric constant - 13: Correction out of bounds, pixel constrained to extreme allowable value - 14: L1B data faulty - 15: Not processed due to deep ocean or clouds - Bits 8-11: Band 2 data quality - 0: Highest quality - 7: Noisy detector - 8: Dead detector, data interpolated in L1B - 9: Solar zenith \\\u003e= 86 degrees - 10: Solar zenith \\\u003e= 85 and \\\u003c 86 degrees - 11: Missing input - 12: Internal constant used in place of climatological data for at least one atmospheric constant - 13: Correction out of bounds, pixel constrained to extreme allowable value - 14: L1B data faulty - 15: Not processed due to deep ocean or clouds - Bit 12: Atmospheric correction performed - 0: No - 1: Yes - Bit 13: Adjacency correction performed - 0: No - 1: Yes - Bits 14-15: Spare (unused) - 0: N/A ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `obscov` | 0 | 100 | 0.01 | meters | None | Observation coverage percent |\n| `iobs_res` | 0 | 254 | | meters | None | Observation number |\n| `orbit_pnt` | 0 | 15 | | meters | None | Orbit pointer |\n| `granule_pnt` | 0 | 254 | | meters | None | Granule pointer |\n\nTerms of Use\n\n**Terms of Use**\n\nMODIS data and products acquired through the LP DAAC\nhave no restrictions on subsequent use, sale, or redistribution.\n\nCitations \nCitations:\n\n- Please visit [LP DAAC 'Citing Our Data' page](https://lpdaac.usgs.gov/citing_our_data)\n for information on citing LP DAAC datasets.\n\nDOIs\n\n- \u003chttps://doi.org/10.5067/MODIS/MOD09GQ.061\u003e\n\nExplore with Earth Engine **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\nCode Editor (JavaScript) \n\n```javascript\nvar dataset = ee.ImageCollection('MODIS/061/MOD09GQ')\n .filter(ee.Filter.date('2018-01-01', '2018-05-01'));\nvar falseColorVis = {\n min: -100.0,\n max: 8000.0,\n bands: ['sur_refl_b02', 'sur_refl_b02', 'sur_refl_b01'],\n};\nMap.setCenter(6.746, 46.529, 2);\nMap.addLayer(dataset, falseColorVis, 'False Color');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/MODIS/MODIS_061_MOD09GQ) \n[MOD09GQ.061 Terra Surface Reflectance Daily Global 250m](/earth-engine/datasets/catalog/MODIS_061_MOD09GQ) \nThe MODIS Surface Reflectance products provide an estimate of the surface spectral reflectance as it would be measured at ground level in the absence of atmospheric scattering or absorption. Low-level data are corrected for atmospheric gases and aerosols. MOD09GQ version 6.1 provides bands 1 and 2 at a 250m resolution ... \nMODIS/061/MOD09GQ, daily,global,modis,nasa,satellite-imagery,sr,surface-reflectance,terra,usgs \n2000-02-24T00:00:00Z/2025-08-30T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.5067/MODIS/MOD09GQ.061](https://doi.org/https://doi.org/10.5067/MODIS/MOD09GQ.061)\n- [https://doi.org/10.5067/MODIS/MOD09GQ.061](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MOD09GQ)"]]
