Combined MODIS EVI 2 data from the MCD12Q2 product over the Great Lakes region, United States, 2016.View full-size image
The Terra and Aqua combined Moderate Resolution Imaging Spectroradiometer (MODIS) Land Cover Dynamics (MCD12Q2) Version 6 data product provides global land surface phenology metrics at yearly intervals from 2001 to 2018. The MCD12Q2 Version 6 data product is derived from time series of the 2-band Enhanced Vegetation Index (EVI2) calculated from MODIS Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectance (NBAR). Vegetation phenology metrics at 500 meter spatial resolution are identified for up to two detected growing cycles per year. For pixels with more than two valid vegetation cycles, the data represent the two cycles with the largest NBAR-EVI2 amplitudes.
Provided in each MCD12Q2 Version 6 Hierarchical Data Format 4 (HDF4) file are layers for the total number of vegetation cycles detected for the product year, the onset of greenness, greenup midpoint, maturity, peak greenness, senescence, greendown midpoint, dormancy, EVI2 minimum, EVI2 amplitude, integrated EVI2 over a vegetation cycle, as well as overall and phenology metric-specific quality information. A low-resolution browse image showing greenup is also available when viewing each MCD12Q2 granule. SDS layers may be multi-dimensional with up to two valid vegetation cycles.
For areas where the NBAR-EVI2 values are missing due to cloud cover or other reasons, the data gaps are filled with good quality NBAR-EVI2 values from the year directly preceding or following the product year.
|File Size||~275 MB|
|Temporal Extent||2001-01-01 to 2018-12-31|
|Geographic Dimensions||1200 km x 1200 km|
|Number of Science Dataset (SDS) Layers||13|
|Columns/Rows||2400 x 2400|
|Pixel Size||500 m|
|SDS Name||Description||Units||Data Type||Fill Value||No Data Value||Valid Range||Scale Factor|
|NumCycles||Total number of valid vegetation cycles with peak in product year||Number||16-bit signed integer||32767||N/A||0 to 7||N/A|
|Greenup¹||Date when EVI2 first crossed 15% of the segment EVI2 amplitude||Day||16-bit signed integer||32767||N/A||11138 to 32766||N/A|
|MidGreenup¹||Date when EVI2 first crossed 50% of the segment EVI2 amplitude||Day||16-bit signed integer||32767||N/A||11138 to 32766||N/A|
|Peak¹||Date when EVI2 reached the segment maximum||Day||16-bit signed integer||32767||N/A||11138 to 32766||N/A|
|Maturity¹||Date when EVI2 first crossed 90% of the segment EVI2 amplitude||Day||16-bit signed integer||32767||N/A||11138 to 32766||N/A|
|MidGreendown¹||Date when EVI2 last crossed 50% of the segment EVI2 amplitude||Day||16-bit signed integer||32767||N/A||11138 to 32766||N/A|
|Senescence¹||Date when EVI2 last crossed 90% of the segment EVI2 amplitude||Day||16-bit signed integer||32767||N/A||11138 to 32766||N/A|
|Dormancy¹||Date when EVI2 last crossed 15% of the segment EVI2 amplitude||Day||16-bit signed integer||32767||N/A||11138 to 32766||N/A|
|EVI_Minimum||Segment minimum EVI2 value||EVI2||16-bit signed integer||32767||N/A||0 to 10000||0.0001|
|EVI_Amplitude||Segment maximum - minimum EVI2||EVI2||16-bit signed integer||32767||N/A||0 to 10000||0.0001|
|EVI_Area||Sum of daily interpolated EVI2 from Greenup to Dormancy||EVI2||16-bit signed integer||32767||N/A||0 to 3700||0.1|
|QA_Overall||QA code for entire segment||Class||16-bit signed integer||32767||N/A||0 to 3||N/A|
|QA_Detailed||Bit-packed, SDS-specific QA codes||Bit Field||16-bit signed integer||32767||N/A||0 to 16383||N/A|
¹Phenometric-specific units are days since January 1, 1970.
Quality information is provided on page 8 of the User Guide.
The Quality Control (QC) layer is stored in an efficient bit-encoded manner. The unpack_sds_bits executable from the LDOPE Tools is available to the user community to help parse and interpret the quality layer.
Quality assurance information should be considered when determining the usability of data for a particular science application. The ArcGIS MODIS-VIIRS Python Toolbox contains tools capable of decoding quality data layers while producing thematic quality raster files for each quality attribute.
In addition to data access and transformation processes, AppEEARS also has the capability to unpack and interpret the quality layers.
Known issues are described on pages 5 and 6 of the User Guide.