המוצר MYD09Q1 מספק אומדן של ההחזרות הספקטרליות של פני השטח של פסי 1 ו-2 ברזולוציה של 250 מ' ומתוקן לתנאים אטמוספריים כמו גזים, אירוסולים ופיזור ריילי. בנוסף לשני פסי ההחזרות, נכללת גם שכבת איכות. לכל פיקסל נבחר ערך מכל הרכישות בתוך הקומפוזיציה של 8 ימים על בסיס כיסוי גבוה של התצפית, זווית צפייה נמוכה, היעדר עננים או צל של עננים ועומס אירוסולים.
המוצר MYD09Q1 מספק הערכה של ההחזרת הספקטרלית של פני השטח של תדרים 1 ו-2 ברזולוציה של 250 מ' ותיקון של תנאים אטמוספריים כמו גזים, אירוסולים ופיזור ריילי. בנוסף לשני פסי ההחזרה, נכללת גם שכבת איכות. לכל פיקסל נבחר ערך …
[null,null,[],[[["\u003cp\u003eMYD09Q1 provides an estimate of surface spectral reflectance for bands 1 and 2 at 250m resolution, corrected for atmospheric conditions.\u003c/p\u003e\n"],["\u003cp\u003eIt includes a quality layer and selects pixel values based on observation coverage, view angle, and absence of clouds or cloud shadow.\u003c/p\u003e\n"],["\u003cp\u003eData is composited over an 8-day period and includes bands for surface reflectance, state flags, and quality control.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset is available from July 4, 2002, to November 24, 2024, and is provided by NASA LP DAAC at the USGS EROS Center.\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"]]],["The MYD09Q1 dataset, provided by NASA LP DAAC, offers 8-day composites of surface spectral reflectance for bands 1 and 2, corrected for atmospheric conditions, at a 250m resolution from 2002-07-04 to 2025-02-10. It includes a quality layer and is accessible through Google Earth Engine using the snippet `ee.ImageCollection(\"MODIS/061/MYD09Q1\")`. Data is provided without restrictions and offers detailed information on pixel state and quality through bitmasking.\n"],null,["# MYD09Q1.061 Aqua Surface Reflectance 8-Day Global 250m\n\nDataset Availability\n: 2002-07-04T00:00:00Z--2025-08-13T00:00:00Z\n\nDataset Provider\n:\n\n\n [NASA LP DAAC at the USGS EROS Center](https://doi.org/10.5067/MODIS/MYD09Q1.061)\n\nCadence\n: 8 Days\n\nTags\n:\n [8-day](/earth-engine/datasets/tags/8-day) [aqua](/earth-engine/datasets/tags/aqua) [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) [usgs](/earth-engine/datasets/tags/usgs) \nmyd09q1 \n\n#### Description\n\nThe MYD09Q1 product provides an estimate of the surface\nspectral reflectance of bands 1 and 2 at 250m resolution and corrected\nfor atmospheric conditions such as gasses, aerosols, and Rayleigh\nscattering. Along with the two reflectance bands, a quality layer\nis also included. For each pixel, a value is selected from all\nthe acquisitions within the 8-day composite on the basis of high\nobservation coverage, low view angle, the absence of clouds or\ncloud shadow, and aerosol loading.\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/MYD09Q1)\n\n### Bands\n\n\n**Pixel Size**\n\n250 meters\n\n**Bands**\n\n| Name | Min | Max | Scale | Pixel Size | Wavelength | Description |\n|----------------|------|-------|--------|------------|------------|-----------------------------------------------------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|\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| `State` | | | | meters | None | Surface reflectance 250m state flags |\n| Bitmask for State - Bits 0-1: Cloud state - 0: Clear - 1: Cloudy - 2: Mixed - 3: Not set, assumed clear - Bit 2: Cloud shadow - 0: No - 1: Yes - Bits 3-5: Land/water flag - 0: Shallow ocean - 1: Land - 2: Ocean coastlines and lake shorelines - 3: Shallow inland water - 4: Ephemeral water - 5: Deep inland water - 6: Continental/moderate ocean - 7: Deep ocean - Bits 6-7: Aerosol quantity - 0: Climatology - 1: Low - 2: Average - 3: High - Bits 8-9: Cirrus detected - 0: None - 1: Small - 2: Average - 3: High - Bit 10: Internal cloud algorithm flag - 0: No cloud - 1: Cloud - Bit 11: Internal fire algorithm flag - 0: No fire - 1: Fire - Bit 12: MOD35 snow/ice flag - 0: No - 1: Yes - Bit 13: Pixel is adjacent to cloud - 0: No - 1: Yes - Bit 14: BRDF correction performed data - 0: No - 1: Yes - Bit 15: Internal snow mask - 0: No snow - 1: Snow ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `QA` | | | | meters | None | Surface reflectance 250m band quality control flags |\n| Bitmask for QA - 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 - Bit 14: Different orbit from 500m - 0: No - 1: Yes - Bit 15: Spare (unused) - 0: N/A ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n\n### Terms 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\n### Citations\n\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\n### DOIs\n\n- \u003chttps://doi.org/10.5067/MODIS/MYD09Q1.061\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/MYD09Q1')\n .filter(ee.Filter.date('2018-01-01', '2018-05-01'));\n\nvar falseColorVis = {\n min: -100.0,\n max: 6000.0,\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_MYD09Q1) \n[MYD09Q1.061 Aqua Surface Reflectance 8-Day Global 250m](/earth-engine/datasets/catalog/MODIS_061_MYD09Q1) \nThe MYD09Q1 product provides an estimate of the surface spectral reflectance of bands 1 and 2 at 250m resolution and corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering. Along with the two reflectance bands, a quality layer is also included. For each pixel, a value is selected ... \nMODIS/061/MYD09Q1, 8-day,aqua,global,modis,nasa,satellite-imagery,sr,surface-reflectance,usgs \n2002-07-04T00:00:00Z/2025-08-13T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.5067/MODIS/MYD09Q1.061](https://doi.org/https://doi.org/10.5067/MODIS/MYD09Q1.061)\n- [https://doi.org/10.5067/MODIS/MYD09Q1.061](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MYD09Q1)"]]
