Sản phẩm MCD43A4 V6.1 Nadir Bidirectional Reflectance Distribution Function Adjusted Reflectance (NBAR) cung cấp dữ liệu phản xạ 500 mét của các dải "đất" 1-7 của MODIS. Những giá trị này được điều chỉnh bằng hàm phân phối độ phản xạ hai chiều để mô hình hoá các giá trị như thể chúng được thu thập từ chế độ xem thiên đỉnh. Dữ liệu được tạo hằng ngày dựa trên khoảng thời gian truy xuất là 16 ngày, trong đó ngày của hình ảnh là ngày thứ 9. Sản phẩm này kết hợp dữ liệu từ cả tàu vũ trụ Terra và Aqua, chọn pixel đại diện tốt nhất trong khoảng thời gian 16 ngày.
Sản phẩm Phản xạ đã điều chỉnh theo hàm phân phối phản xạ hai chiều tại điểm thiên đỉnh MCD43A4 phiên bản 6.1 (NBAR) cung cấp dữ liệu phản xạ 500 mét của các dải "đất" 1-7 của MODIS. Các giá trị này được điều chỉnh bằng hàm phân phối độ phản xạ hai chiều để mô hình hoá các giá trị như thể chúng được thu thập từ chế độ xem thiên đỉnh. Dữ liệu được tạo hằng ngày …
[null,null,[],[[["\u003cp\u003eThe MCD43A4 V6.1 product provides daily, 500-meter resolution, Nadir BRDF-Adjusted Reflectance (NBAR) data for MODIS land bands 1-7.\u003c/p\u003e\n"],["\u003cp\u003eReflectance data is adjusted using a bidirectional reflectance distribution function to simulate a nadir view, combining data from Terra and Aqua satellites.\u003c/p\u003e\n"],["\u003cp\u003eThe product offers daily imagery based on a 16-day retrieval period, with the image date representing the 9th day of the period.\u003c/p\u003e\n"],["\u003cp\u003eBands include Nadir Reflectance for bands 1-7 and BRDF Albedo Mandatory Quality bands for quality assessment.\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 MCD43A4 V6.1 dataset provides daily 500-meter reflectance data from MODIS \"land\" bands 1-7, spanning from February 24, 2000, to February 11, 2025. Data is adjusted with a bidirectional reflectance distribution function (BRDF), modeling nadir view reflectance. The data comes from NASA's Terra and Aqua spacecrafts, with the best pixel being chosen. It can be accessed through Earth Engine using `ee.ImageCollection(\"MODIS/061/MCD43A4\")`. The dataset is provided by NASA LP DAAC at the USGS EROS Center.\n"],null,["Dataset Availability\n: 2000-02-24T00:00:00Z--2025-08-20T00:00:00Z\n\nDataset Provider\n:\n\n\n [NASA LP DAAC at the USGS EROS Center](https://doi.org/10.5067/MODIS/MCD43A4.061)\n\nCadence\n: 1 Day\n\nTags\n:\n[albedo](/earth-engine/datasets/tags/albedo) [brdf](/earth-engine/datasets/tags/brdf) [daily](/earth-engine/datasets/tags/daily) [global](/earth-engine/datasets/tags/global) [modis](/earth-engine/datasets/tags/modis) [nasa](/earth-engine/datasets/tags/nasa) [reflectance](/earth-engine/datasets/tags/reflectance) [satellite-imagery](/earth-engine/datasets/tags/satellite-imagery) [usgs](/earth-engine/datasets/tags/usgs) \n\nDescription \nThe MCD43A4 V6.1 Nadir Bidirectional Reflectance Distribution\nFunction Adjusted Reflectance (NBAR) product provides 500 meter\nreflectance data of the MODIS \"land\" bands 1-7. These are adjusted\nusing a bidirectional reflectance distribution function to model\nthe values as if they were collected from a nadir view. The data\nare produced daily based on a 16-day retrieval period, with the\nimage's date occurring on the 9th day. This product combines data\nfrom both the Terra and Aqua spacecrafts, choosing the best representative\npixel from the 16-day period.\n\nDocumentation:\n\n- [User's Guide](https://www.umb.edu/spectralmass/terra_aqua_modis/v006)\n\n- [Algorithm Theoretical Basis Document (ATBD)](https://lpdaac.usgs.gov/documents/97/MCD43_ATBD.pdf)\n\n- [General Documentation](https://ladsweb.modaps.eosdis.nasa.gov/filespec/MODIS/61/MCD43A4)\n\nBands\n\n\n**Pixel Size**\n\n500 meters\n\n**Bands**\n\n| Name | Min | Max | Scale | Pixel Size | Wavelength | Description |\n|--------------------------------------------|-----|-------|--------|------------|-------------|------------------------------------------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|\n| `Nadir_Reflectance_Band1` | 0 | 32766 | 0.0001 | meters | 620-670nm | NBAR at local solar noon for band 1 |\n| `Nadir_Reflectance_Band2` | 0 | 32766 | 0.0001 | meters | 841-876nm | NBAR at local solar noon for band 2 |\n| `Nadir_Reflectance_Band3` | 0 | 32766 | 0.0001 | meters | 459-479nm | NBAR at local solar noon for band 3 |\n| `Nadir_Reflectance_Band4` | 0 | 32766 | 0.0001 | meters | 545-565nm | NBAR at local solar noon for band 4 |\n| `Nadir_Reflectance_Band5` | 0 | 32766 | 0.0001 | meters | 1230-1250nm | NBAR at local solar noon for band 5 |\n| `Nadir_Reflectance_Band6` | 0 | 32766 | 0.0001 | meters | 1628-1652nm | NBAR at local solar noon for band 6 |\n| `Nadir_Reflectance_Band7` | 0 | 32766 | 0.0001 | meters | 2105-2155nm | NBAR at local solar noon for band 7 |\n| `BRDF_Albedo_Band_Mandatory_Quality_Band1` | | | | meters | None | BRDF albedo mandatory quality for band 1 |\n| Bitmask for BRDF_Albedo_Band_Mandatory_Quality_Band1 - Bit 0: Mandatory QA bit index - 0: Processed, good quality (full BRDF inversions) - 1: Processed, see other QA (magnitude BRDF inversions) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `BRDF_Albedo_Band_Mandatory_Quality_Band2` | | | | meters | None | BRDF albedo mandatory quality for band 2 |\n| Bitmask for BRDF_Albedo_Band_Mandatory_Quality_Band2 - Bit 0: Mandatory QA bit index - 0: Processed, good quality (full BRDF inversions) - 1: Processed, see other QA (magnitude BRDF inversions) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `BRDF_Albedo_Band_Mandatory_Quality_Band3` | | | | meters | None | BRDF albedo mandatory quality for band 3 |\n| Bitmask for BRDF_Albedo_Band_Mandatory_Quality_Band3 - Bit 0: Mandatory QA bit index - 0: Processed, good quality (full BRDF inversions) - 1: Processed, see other QA (magnitude BRDF inversions) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `BRDF_Albedo_Band_Mandatory_Quality_Band4` | | | | meters | None | BRDF albedo mandatory quality for band 4 |\n| Bitmask for BRDF_Albedo_Band_Mandatory_Quality_Band4 - Bit 0: Mandatory QA bit index - 0: Processed, good quality (full BRDF inversions) - 1: Processed, see other QA (magnitude BRDF inversions) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `BRDF_Albedo_Band_Mandatory_Quality_Band5` | | | | meters | None | BRDF albedo mandatory quality for band 5 |\n| Bitmask for BRDF_Albedo_Band_Mandatory_Quality_Band5 - Bit 0: Mandatory QA bit index - 0: Processed, good quality (full BRDF inversions) - 1: Processed, see other QA (magnitude BRDF inversions) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `BRDF_Albedo_Band_Mandatory_Quality_Band6` | | | | meters | None | BRDF albedo mandatory quality for band 6 |\n| Bitmask for BRDF_Albedo_Band_Mandatory_Quality_Band6 - Bit 0: Mandatory QA bit index - 0: Processed, good quality (full BRDF inversions) - 1: Processed, see other QA (magnitude BRDF inversions) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `BRDF_Albedo_Band_Mandatory_Quality_Band7` | | | | meters | None | BRDF albedo mandatory quality for band 7 |\n| Bitmask for BRDF_Albedo_Band_Mandatory_Quality_Band7 - Bit 0: Mandatory QA bit index - 0: Processed, good quality (full BRDF inversions) - 1: Processed, see other QA (magnitude BRDF inversions) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\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/MCD43A4.061\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/MCD43A4')\n .filter(ee.Filter.date('2018-04-01', '2018-06-01'));\nvar trueColor = dataset.select([\n 'Nadir_Reflectance_Band1', 'Nadir_Reflectance_Band4',\n 'Nadir_Reflectance_Band3'\n]);\nvar trueColorVis = {\n min: 0.0,\n max: 4000.0,\n gamma: 1.4,\n};\nMap.setCenter(-7.03125, 31.0529339857, 2);\nMap.addLayer(trueColor, trueColorVis, 'True Color');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/MODIS/MODIS_061_MCD43A4) \n[MCD43A4.061 MODIS Nadir BRDF-Adjusted Reflectance Daily 500m](/earth-engine/datasets/catalog/MODIS_061_MCD43A4) \nThe MCD43A4 V6.1 Nadir Bidirectional Reflectance Distribution Function Adjusted Reflectance (NBAR) product provides 500 meter reflectance data of the MODIS \"land\" bands 1-7. These are adjusted using a bidirectional reflectance distribution function to model the values as if they were collected from a nadir view. The data are produced daily ... \nMODIS/061/MCD43A4, albedo,brdf,daily,global,modis,nasa,reflectance,satellite-imagery,usgs \n2000-02-24T00:00:00Z/2025-08-20T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.5067/MODIS/MCD43A4.061](https://doi.org/https://doi.org/10.5067/MODIS/MCD43A4.061)\n- [https://doi.org/10.5067/MODIS/MCD43A4.061](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MCD43A4)"]]
