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EDG Data Set Name	Granule Shortname
MODIS/Terra Vegetation Cover Conversion 96-Day L3 Global 250m SIN Grid	MOD44A

Version	Acquisition Range	Science Quality Status
V003	April 7, 2002 (2002097) - October 16, 2002 (2002289)	Beta
V004	January 1, 2002 (2002001)	No status available

Data Set Characteristics
Area = ~ 10° x 10° lat/long
Image Dimensions Metrics = 3 (4800X4800X12 row/column/metric)
Image Dimensions Change = 2 (4800x4800 row/column)
Average File Size = ~ 600 MB
Resolution = 250 meters
Projection = Sinusoidal
Data Format = HDF-EOS
Science Data Sets (SDSs) = 5

Product Description
The MODerate-resolution Imaging Spectroradiometer (MODIS) Vegetation Cover Conversion (VCC) product is produced on a quarterly basis comparing data from the 3 months of the current year to the same 3 months of the previous year. The input for the quarterly VCC is an intermediately produced 250m resolution composite derived from 16 days of daily data by performing a quality based per pixel method, which selects the most cloud free data. Each of these composites is processed separately and change is detected by comparison of the images.

The MODIS/Terra Vegetation Cover Conversion Quarterly L3 Global 250m SIN Grid product, MOD44A, currently reports only change from forest to non-forest (deforestation) for the humid tropical regions of the globe (30 deg N latitude to 30 deg S. latitude). In future versions change will be reported for deforestation for the rest of the globe and for flooding on a global scale. Forest cover is defined by using the Vegetation Continuous Fields product (MOD44B) and considering anything with 60% tree cover or more to be forest. This is consistent with the IGBP classification of a forest. Non-forest is defined as less than 40% tree cover. Any pixel that was identified as forest in year 1 and was then identified as non-forest in year 2 is flagged and recorded in one of the metrics layers. When all of the 16-day periods have been processed the metrics (intermediate classification comparison) layers are compared. Any pixel that has been flagged in at least 2 of the metrics layers is recorded in the "labeled land cover change" layer. Categorical quality assurance, determined by the quality of the input data, is provided in the "labeled land cover change QA" layer. For specific information regarding values refer to the product user guide.

The MOD44A imagery above indicates vegetative cover conversion in the state of Mato Grosso in Brazil. The visualization is a 250m resolution subset from tile h12v10 depicting a reduction in tree cover from 2001 and 2002. The far right image is a representation of the MOD44A product, in which pixels experiencing significant change are identified explicitly.

NOTE: These products are Validated, Stage 1, meaning that product accuracy has been estimated using a small number of independent measurements obtained from selected locations and time periods and ground-truth/field program effort.

Valid Range: 0 - 255
0: No change detected
1: Tree Cover Change
255. Fill

SDS	Data Type	Fill Value	Valid Range
Land Cover Change Metrics Past 1 Year	16-bit unsigned integer	0	0 - 65535
Labeled Land Cover Change Past 1 Year	8-bit unsigned integer	255	0 - 255
Labeled Land Cover Change Past 1 Year QA	8-bit unsigned integer	255	0 - 255
Algorithm Path Past 1 Year	16-bit unsigned integer	0	0 - 65535

View a Version Formatted for Printing

Retrieve the MOD44Av4 MODIS product through the LP DAAC Data Pool
Via Search Tool: http://e4eil01u.ecs.nasa.gov:22000/WebAccess/drill?attrib=esdt&esdt=MOD44A.4&group=MOLT
Via FTP Directory: ftp://e4ftl01u.ecs.nasa.gov/MOLT/MOD44A.004/

Order These Data through the EOS Data Gateway
MODIS/TERRA VEGETATION COVER CONVERSION 96-DAY L3 GLOBAL 250M SIN GRID V004

Product Information

Product Description (http://landval.gsfc.nasa.gov/MODLAND/vcc.htm)

User Guide (http://glcf.umiacs.umd.edu/pdf/VCCuserguide.pdf)

Algorithm Theoretical Basis Document (ATBD) (http://modis.gsfc.nasa.gov/data/atbd/land_atbd.php)

MODIS Standard Data Products Catalog (http://modis.gsfc.nasa.gov/data/dataprod/index.php)

EOS Data Products Handbook Volume 1 (2000) (http://eospso.gsfc.nasa.gov/eos_homepage/for_scientists/data_products/vol1.php)

Contact Information

LP DAAC User Services U.S. Geological Survey (USGS) Earth Resources Observation and Science Center (EROS) 47914 252nd Street Sioux Falls, SD 57198-0001
Phone:	605-594-6116
Toll Free:	866-573-3222
	866-LPE-DAAC
Fax:	605-594-6963
Email:	LPDAAC@eos.nasa.gov
Web:	http://LPDAAC.usgs.gov

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