A combination of Bands 2, 2, 1 displays a false-color Surface Reflectance image using 250-m data acquired between April 7 - 14, 2007 over central Europe (h18v04). The Alps are prominent snow-covered features, appearing in white across the center of the image.
The 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, yielding a level-2 basis for several higher-order gridded level-2 (L2G) and level-3 products.
MYD09Q1 provides Bands 1 and 2 at 250-meter resolution in an 8-day gridded level-3 product in the Sinusoidal projection. Each MYD09Q1 pixel contains the best possible L2G observation during an 8-day period as selected on the basis of high observation coverage, low view angle, the absence of clouds or cloud shadow, and aerosol loading. Science Data Sets provided for this product include reflectance values for Bands 1 and 2, and a quality rating.
Version-5 MODIS/Aqua Surface Reflectance products are Validated Stage 2, meaning that accuracy has been assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts. Although there may be later improved versions, these data are ready for use in scientific publications.
Temporal Coverage | July 4, 2002 - |
Area | ~10 x 10 lat/long |
File Size | ~55 MB |
Projection | Sinusoidal |
Data Format | HDF-EOS |
Dimensions | 4800 x 4800 rows/columns |
Resolution | 250 meters |
Science Data Sets (SDS HDF Layers) | 3 |
Science Data Sets for MODIS Aqua Surface Reflectance 8-Day L3 Global 250m SIN Grid V005 (MYD09Q1):
Science Data Sets (HDF Layers) (3) |
UNITS |
BIT TYPE |
FILL |
VALID RANGE |
MULTIPLY BY SCALE FACTOR |
---|---|---|---|---|---|
250m Surface Reflectance Band 1 (620–670 nm) | Reflectance | 16-bit signed integer | -28672 | -100–16000 | 0.0001 |
250m Surface Reflectance Band 2 (841–876 nm) | Reflectance | 16-bit signed integer | -28672 | -100–16000 | 0.0001 |
250m Reflectance Band Quality | Bit Field | 16-bit unsigned integer | 65535 | 0–32767 | na |
The QA information below is excerpted from an HDF-EOS file of the MODIS Surface Reflectance product MYD09Q1.
Table 1: MYD09Q1.005 250-meter Surface Reflectance Data QA Descriptions (16-bit)
Bit No. |
Parameter Name |
Bit Comb. |
Sur_refl_qc_250m |
---|---|---|---|
15 | spare (unused) | - | --- |
14 | different orbit from 500 m | 1 | yes |
0 | no | ||
13 | adjacency correction performed | 1 | yes |
0 | no | ||
12 | atmospheric correction performed | 1 | yes |
0 | no | ||
8–11 | band 2 data quality four bit range | 0000 | highest quality |
1000 | dead detector; data copied from adjacent detector | ||
1001 | solar zenith >= 86 degrees | ||
1010 | solar zenith >= 85 and < 86 degrees | ||
1011 | missing input | ||
1100 | internal constant used in place of climatological data for at least one atmospheric constant | ||
1101 | quality so low that it is not useful | ||
1110 | L1B data faulty | ||
1111 | not useful for any other reason or not processed due to deep ocean or clouds | ||
4–7 | band 1 data quality four bit range | SAME AS ABOVE | |
2–3 | cloud state | 00 | clear |
01 | cloudy | ||
10 | mixed | ||
11 | not set; assumed clear | ||
0–1 | MODLAND QA bits | 00 | corrected product produced at ideal quality all bands |
01 | corrected product produced at less than ideal quality some or all bands | ||
10 | corrected product not produced due to cloud effects all bands | ||
11 | corrected product not produced due to other reasons some or all bands may be fill value [Note that a value of (11) overrides a value of (01)]. |
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In the event that data distributed from the Land Processes DAAC are incorporated into your research, please supply the following acknowledgment within your published work: "These data are distributed by the Land Processes Distributed Active Archive Center (LP DAAC), located at the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center (lpdaac.usgs.gov)." If possible, please e-mail or send us reprints/citations of papers or oral presentations based on data obtained from the LP DAAC (see below for mailing address and e-mail address). This will help us to stay informed of how the data are being utilized.
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U.S. Geological Survey (USGS)
Earth Resources Observation and Science (EROS) Center
47914 252nd Street
Sioux Falls, SD 57198-0001
The complete data record for this product is available through the WIST search and order interface. A near-complete record is available on-line through the Data Pool.
Please find links to (and information about) these data access tools on the Get Data Section of this Web Site.
U.S. Geological Survey (USGS)
Center for Earth Resources Observation and Science (EROS)
47914 252nd Street
Sioux Falls, SD 57198-0001
Phone Number: | 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 |