Product Quality Documentation for MOD13Q1, C5



Collection C5

ParameterName: All
BeginDateTimeEndDateTime ScienceQualityFlagScienceQualityFlagExplanation CommentsMaturity
2000 049
(02/18/00)
2000 112
(04/21/00)
Inferred Passed The MODIS Vegetation Index product is retrieved accurately using a state of the art MODIS specific, quality driven, constrained view angle, maximum value composite method. For most cloud and snow free, low aerosol load pixels, the VI values are very reliable. The VI product is particularly dependent on coherent inter-band (blue, red and NIR) atmosphere correction and unstable values may be encountered over more extreme bright or dark surfaces. Over inland water bodies (rivers, lakes, etc...) surface reflectance inputs and VI values may not be stable and should be used with caution. Various field and flux tower validation campaigns indicate good agreement of VI values with land surface biophysical properties for most biomes, and cross sensor VI correlations (AVHRR, Landsat, SPOT, etc...) are very strong. Strong agreements are also found with the nadir-adjusted (NBAR) VI products. Users are advised to examine the per-pixel product quality to screen poor data before applying it to project-applications, science, and research. We will report any further findings with ongoing product assessments. Unstable VI values may occur over inland water bodies and snow/ice covered targets. Products made for data day 2000065 using the data acquired between 2000076:18:45:00 and 2000076:19:10:00 and between 2000076:20:20:00 and 2000076:20:50:00 may have geolocation error casued by the spacecraft maneuver. Validated Stage 3
2000 113
(04/22/00)
2000 128
(05/07/00)
Suspect MODIS nadir aperture door was closed part time on 2000116 and 2000119, all time on 2000117 and 2000118.   Validated Stage 3
2000 129
(05/08/00)
2000 216
(08/03/00)
Inferred Passed The MODIS Vegetation Index product is retrieved accurately using a state of the art MODIS specific, quality driven, constrained view angle, maximum value composite method. For most cloud and snow free, low aerosol load pixels, the VI values are very reliable. The VI product is particularly dependent on coherent inter-band (blue, red and NIR) atmosphere correction and unstable values may be encountered over more extreme bright or dark surfaces. Over inland water bodies (rivers, lakes, etc...) surface reflectance inputs and VI values may not be stable and should be used with caution. Various field and flux tower validation campaigns indicate good agreement of VI values with land surface biophysical properties for most biomes, and cross sensor VI correlations (AVHRR, Landsat, SPOT, etc...) are very strong. Strong agreements are also found with the nadir-adjusted (NBAR) VI products. Users are advised to examine the per-pixel product quality to screen poor data before applying it to project-applications, science, and research. We will report any further findings with ongoing product assessments. Unstable VI values may occur over inland water bodies and snow/ice covered targets. Validated Stage 3
2000 217
(08/04/00)
2000 232
(08/19/00)
Suspect MODIS-L1B data was not available for days 2000219 - 2000230 due to L1B formatter anamoly.   Validated Stage 3
2000 233
(08/20/00)
2001 144
(05/24/01)
Inferred Passed The MODIS Vegetation Index product is retrieved accurately using a state of the art MODIS specific, quality driven, constrained view angle, maximum value composite method. For most cloud and snow free, low aerosol load pixels, the VI values are very reliable. The VI product is particularly dependent on coherent inter-band (blue, red and NIR) atmosphere correction and unstable values may be encountered over more extreme bright or dark surfaces. Over inland water bodies (rivers, lakes, etc...) surface reflectance inputs and VI values may not be stable and should be used with caution. Various field and flux tower validation campaigns indicate good agreement of VI values with land surface biophysical properties for most biomes, and cross sensor VI correlations (AVHRR, Landsat, SPOT, etc...) are very strong. Strong agreements are also found with the nadir-adjusted (NBAR) VI products. Users are advised to examine the per-pixel product quality to screen poor data before applying it to project-applications, science, and research. We will report any further findings with ongoing product assessments. Unstable VI values may occur over inland water bodies and snow/ice covered targets. Validated Stage 3
2001 145
(05/25/01)
2001 160
(06/09/01)
Suspect Some of the files may have large geolocation error. Use of incorrect ephemeris/attitude in processing of some of the MODIS L0 granules has resulted in geolocation error larger than 20m and this error has propogated into the downstream products. Discretion should be exercised in use of this product. Affected granules are from the three two hour periods starting 2001-05-29T14:00 (doy 149), 2001-05-30T16:00 (doy 150) and 2001-05-30T22:00 (doy 150). Validated Stage 3
2001 161
(06/10/01)
2001 192
(07/11/01)
Suspect Product quality may have been effected due to use of only 9 days of input data since no L1B was available for data day 2001166 - 2001183. MODIS was OFF on these days after being shut off on 2001166 due to SAA. Discretion should be exercised in use of this product.   Validated Stage 3
2001 193
(07/12/01)
2002 064
(03/05/02)
Inferred Passed The MODIS Vegetation Index product is retrieved accurately using a state of the art MODIS specific, quality driven, constrained view angle, maximum value composite method. For most cloud and snow free, low aerosol load pixels, the VI values are very reliable. The VI product is particularly dependent on coherent inter-band (blue, red and NIR) atmosphere correction and unstable values may be encountered over more extreme bright or dark surfaces. Over inland water bodies (rivers, lakes, etc...) surface reflectance inputs and VI values may not be stable and should be used with caution. Various field and flux tower validation campaigns indicate good agreement of VI values with land surface biophysical properties for most biomes, and cross sensor VI correlations (AVHRR, Landsat, SPOT, etc...) are very strong. Strong agreements are also found with the nadir-adjusted (NBAR) VI products. Users are advised to examine the per-pixel product quality to screen poor data before applying it to project-applications, science, and research. We will report any further findings with ongoing product assessments. Unstable VI values may occur over inland water bodies and snow/ice covered targets. Products made for data day 2001273 using the data acquired between 2001275:18:50:00 and 2001275:18:55:00 may have geolocation error casued by the spacecraft maneuver. Validated Stage 3
2002 065
(03/06/02)
2002 096
(04/06/02)
Suspect Product quality may have been effected due to use of significantly lesser number of input data days since no L1B was available for data day 2002073 - 2002087. MODIS was OFF on these days. Discretion should be exercised in use of this product.   Validated Stage 3
2002 097
(04/07/02)
2007 144
(05/24/07)
Inferred Passed The MODIS Vegetation Index product is retrieved accurately using a state of the art MODIS specific, quality driven, constrained view angle, maximum value composite method. For most cloud and snow free, low aerosol load pixels, the VI values are very reliable. The VI product is particularly dependent on coherent inter-band (blue, red and NIR) atmosphere correction and unstable values may be encountered over more extreme bright or dark surfaces. Over inland water bodies (rivers, lakes, etc...) surface reflectance inputs and VI values may not be stable and should be used with caution. Various field and flux tower validation campaigns indicate good agreement of VI values with land surface biophysical properties for most biomes, and cross sensor VI correlations (AVHRR, Landsat, SPOT, etc...) are very strong. Strong agreements are also found with the nadir-adjusted (NBAR) VI products. Users are advised to examine the per-pixel product quality to screen poor data before applying it to project-applications, science, and research. We will report any further findings with ongoing product assessments. Unstable VI values may occur over inland water bodies and snow/ice covered targets. Validated Stage 3
2007 145
(05/25/07)
2007 160
(06/09/07)
Inferred Passed The MODIS Vegetation Index product is retrieved accurately using a state of the art MODIS specific, quality driven, constrained view angle, maximum value composite method. For most cloud and snow free, low aerosol load pixels, the VI values are very reliable. The VI product is particularly dependent on coherent inter-band (blue, red and NIR) atmosphere correction and unstable values may be encountered over more extreme bright or dark surfaces. Over inland water bodies (rivers, lakes, etc...) surface reflectance inputs and VI values may not be stable and should be used with caution. Various field and flux tower validation campaigns indicate good agreement of VI values with land surface biophysical properties for most biomes, and cross sensor VI correlations (AVHRR, Landsat, SPOT, etc...) are very strong. Strong agreements are also found with the nadir-adjusted (NBAR) VI products. Users are advised to examine the per-pixel product quality to screen poor data before applying it to project-applications, science, and research. We will report any further findings with ongoing product assessments. Unstable VI values may occur over inland water bodies and snow/ice covered targets. Daily data for day 2007158 was not available over the entire South America, most of North America, and part of Africa and Europe. Product is made with only 7 days of input data for these area. Validated Stage 3
2007 161
(06/10/07)
. . . Inferred Passed The MODIS Vegetation Index product is retrieved accurately using a state of the art MODIS specific, quality driven, constrained view angle, maximum value composite method. For most cloud and snow free, low aerosol load pixels, the VI values are very reliable. The VI product is particularly dependent on coherent inter-band (blue, red and NIR) atmosphere correction and unstable values may be encountered over more extreme bright or dark surfaces. Over inland water bodies (rivers, lakes, etc...) surface reflectance inputs and VI values may not be stable and should be used with caution. Various field and flux tower validation campaigns indicate good agreement of VI values with land surface biophysical properties for most biomes, and cross sensor VI correlations (AVHRR, Landsat, SPOT, etc...) are very strong. Strong agreements are also found with the nadir-adjusted (NBAR) VI products. Users are advised to examine the per-pixel product quality to screen poor data before applying it to project-applications, science, and research. We will report any further findings with ongoing product assessments. Unstable VI values may occur over inland water bodies and snow/ice covered targets. Validated Stage 3


Updated on 10-16-2009