Los productos de reflectancia de superficie de MODIS proporcionan una estimación de la reflectancia espectral de la superficie tal como se mediría a nivel del suelo en ausencia de dispersión o absorción atmosférica.
Los datos de nivel inferior se corrigen para tener en cuenta los gases y aerosoles atmosféricos.
La versión 6.1 de MYD09GQ proporciona las bandas 1 y 2 con una resolución de 250 m en un producto L2G diario en formato de cuadrícula en la proyección sinusoidal, que incluye un control de calidad y cinco capas de observación. Este producto está diseñado para usarse junto con el MYD09GA, en el que se almacena información importante sobre la calidad y la geometría de visualización.
Control de calidad de la reflectancia de la superficie
Máscara de bits para QC_250m
Bits 0 y 1: Bits de QA de MODLAND
0: Producto corregido con calidad ideal (todas las bandas)
1: Producto corregido con una calidad inferior a la ideal (algunas o todas las bandas)
2: Producto corregido que no se produjo debido a los efectos de las nubes (todas las bandas)
3: El producto corregido no se produjo por otros motivos.
- Algunas o todas las bandas pueden ser un valor de relleno (11) [ten en cuenta que un valor de (11) anula un valor de (01)].
Bits 2 y 3: Repuesto (sin usar)
0: N/A
Bits 4 a 7: Calidad de los datos de la banda 1
0: Calidad más alta
7: Detector ruidoso
8: Detector inactivo, datos interpolados en L1B
9: Ángulo cenital solar >= 86 grados
10: Ángulo cenital solar ≥ 85 y < 86 grados
11: Falta entrada
12: Constante interna que se usa en lugar de los datos climatológicos para al menos una constante atmosférica
13: Corrección fuera de los límites, píxel restringido al valor extremo permitido
14: Los datos de L1B son defectuosos
15: No se procesó debido a la profundidad del océano o a las nubes
Bits 8 a 11: Calidad de los datos de la banda 2
0: Calidad más alta
7: Detector ruidoso
8: Detector inactivo, datos interpolados en L1B
9: Ángulo cenital solar >= 86 grados
10: Ángulo cenital solar ≥ 85 y < 86 grados
11: Falta entrada
12: Constante interna que se usa en lugar de los datos climatológicos para al menos una constante atmosférica
13: Corrección fuera de los límites, píxel restringido al valor extremo permitido
14: Los datos de L1B son defectuosos
15: No se procesó debido a la profundidad del océano o a las nubes
Bit 12: Se realizó la corrección atmosférica
0: No
1: Sí
Bit 13: Se realizó la corrección de adyacencia.
0: No
1: Sí
Bits 14 y 15: Reserva (sin usar)
0: N/A
obscov
0
100
0.01
metros
Ninguno
Porcentaje de cobertura de la observación
iobs_res
0
254
metros
Ninguno
Número de observación
orbit_pnt
0
15
metros
Ninguno
Puntero de órbita
granule_pnt
0
254
metros
Ninguno
Puntero de bolita
Condiciones de Uso
Condiciones de Uso
Los datos y productos de MODIS adquiridos a través del LP DAAC no tienen restricciones sobre su uso, venta o redistribución posteriores.
Los productos de reflectancia de la superficie de MODIS proporcionan una estimación de la reflectancia espectral de la superficie tal como se mediría a nivel del suelo en ausencia de dispersión o absorción atmosférica. Los datos de nivel inferior se corrigen para tener en cuenta los gases y aerosoles atmosféricos. La versión 6.1 de MYD09GQ proporciona las bandas 1 y 2 con una resolución de 250 m…
[null,null,[],[[["\u003cp\u003eMYD09GQ provides daily surface reflectance data at 250m resolution for bands 1 (red) and 2 (near-infrared) from the MODIS sensor on the Aqua satellite.\u003c/p\u003e\n"],["\u003cp\u003eThe data is corrected for atmospheric effects, offering an estimate of surface reflectance as if measured at ground level.\u003c/p\u003e\n"],["\u003cp\u003eThis product includes quality assurance information and observation details, and is best used in conjunction with MYD09GA for complete viewing geometry and quality assessments.\u003c/p\u003e\n"],["\u003cp\u003eData is available from July 4, 2002 to December 9, 2024 and is freely available for use, sale, or redistribution.\u003c/p\u003e\n"],["\u003cp\u003eUsers can access and analyze this dataset through Google Earth Engine using the provided code snippet.\u003c/p\u003e\n"]]],["The NASA MODIS MYD09GQ dataset, provided by the USGS EROS Center, offers daily surface reflectance data from 2002-07-04 to 2025-02-20. It provides bands 1 and 2 at a 250m resolution, corrected for atmospheric gases and aerosols. Key actions include accessing the data via Earth Engine with the snippet `ee.ImageCollection(\"MODIS/061/MYD09GQ\")`, utilizing bands like `sur_refl_b01`, `sur_refl_b02`, and `QC_250m`, and employing quality assurance data. The dataset is globally available without use restrictions.\n"],null,["Dataset Availability\n: 2002-07-04T00:00:00Z--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/MYD09GQ.061)\n\nCadence\n: 1 Day\n\nTags\n:\n [aqua](/earth-engine/datasets/tags/aqua) [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) [usgs](/earth-engine/datasets/tags/usgs) \nmyd09gq \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.\nMYD09GQ 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 MYD09GA 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/MYD09GQ)\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/MYD09GQ.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/MYD09GQ')\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_MYD09GQ) \n[MYD09GQ.061 Aqua Surface Reflectance Daily Global 250m](/earth-engine/datasets/catalog/MODIS_061_MYD09GQ) \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. MYD09GQ version 6.1 provides bands 1 and 2 at a 250m resolution ... \nMODIS/061/MYD09GQ, aqua,daily,global,modis,nasa,satellite-imagery,sr,surface-reflectance,usgs \n2002-07-04T00:00:00Z/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/MYD09GQ.061](https://doi.org/https://doi.org/10.5067/MODIS/MYD09GQ.061)\n- [https://doi.org/10.5067/MODIS/MYD09GQ.061](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MYD09GQ)"]]
