Skip to main content

Description

The MYD09GQ Version 6.1 product provides an estimate of the surface spectral reflectance of Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) 250 meter (m) bands 1 and 2, corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering. Along with the 250 m bands are the Quality Assurance (QA) layer and five observation layers. This product is intended to be used in conjunction with the quality and viewing geometry information of the 500 m product (MYD09GA).

Known Issues

  • Prior to the Aqua MODIS launch, Band 6 exhibited several anomalous detectors. Band 6 performance degraded seriously after launch and presently a majority of the Band 6 detectors are non-functional. Science users should read and use the non-functional detector flags and decide for themselves the optimum manner to handle non-functional detector "gaps" for their products. For complete information please refer to the MODIS Characterization Support Team (MCST) website.
  • For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.

Version Description

The following changes and improvements were implemented for inputs to MODIS Version 6.1 surface reflectance data products: (1) Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 – 2017, and (2) A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).

Product Summary

Platforms
Aqua
Instruments
MODIS
Spatial Extent

N: 90 S: -90 E: 180 W: -180

Spatial Resolution
250 Meters x 250 Meters
Spatial Reference System(s)
MODIS Sinusoidal Tiling System
Location
GLOBAL
Coordinate System
CARTESIAN
Granule Spatial Representation
GEODETIC
Temporal Extent
2002-07-04 to Present
Temporal Resolution
1 Day
Data Partner
Land Processes Distributed Active Archive Center (LP DAAC) ,
MODIS Adaptive Processing System, Terrestrial Information Systems Laboratory, Earth Sciences Division, Science and Exploration Directorate, Goddard Space Flight Center, NASA (NASA/GSFC/SED/ESD/TISL/MODAPS)
Concept ID
C2343109950-LPCLOUD
Data State
ACTIVE
Number of Files/Granules
2680997
Processing Level
2G
Published
Updated
Science Keywords
Reflectance

Citation

Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.

Copy Citation

Vermote, E., & Wolfe, R. (2021). MODIS/Aqua Surface Reflectance Daily L2G Global 250m SIN Grid V061 [Data set]. NASA Land Processes Distributed Active Archive Center. https://doi.org/10.5067/MODIS/MYD09GQ.061 Date Accessed: 2026-02-19

File Naming Convention

MYD09GQ.A2025222.h00v09.061.2025224032058.hdf

The file name begins with the Product Short Name (MYD09GQ) followed by the Julian Date of Acquisition formatted as AYYYYDDD (A2025222), the Tile Identifier which is horizontal tile and vertical tile provided as hXXvYY (h00v09), the Version of the data collection (061), the Julian Date and Time of Production designated as YYYYDDDHHMMSS (2025224032058), and the Data Format (hdf).

Documents

USER'S GUIDE

ALGORITHM THEORETICAL BASIS DOCUMENT (ATBD)

PRODUCT QUALITY ASSESSMENT

SCIENCE DATA PRODUCT VALIDATION

GENERAL DOCUMENTATION

Publications Citing This Dataset

Filters
Title Year Author
Exploring discrepancies between in situ phenology and remotely derived phenometrics at NEON sites Donnelly, A.
A comprehensive characterization of MODIS daily burned area mapping accuracy across fire sizes in tropical savannas Campagnolo, M. L.
Start of the green season and normalized difference vegetation index in alaska’s arctic national parks Swanson, D. K.
Impacts of reduced deposition of atmospheric nitrogen on coastal marine eco-system during substantial shift in human activities in the twenty-first century Mumtaz, F.
Water and hydropower reservoirs: High temporal resolution time series derived from MODIS data to characterize seasonality and variability Klein, I.
Spatial homogeneity from temporal stability: Exploiting the combined hyper-frequent revisit of Terra and Aqua to guide Earth System Science Duveiller, G.
A daily, 250 m and real-time gross primary productivity product (2000-present) covering the contiguous United States Jiang, C.
Total suspended matter distribution in the Hooghly River Estuary and the Sundarbans—A remote sensing approach Jayaram, C.
River flow monitoring by Sentinel-3 OLCI and MODIS—Comparison and combination Tarpanelli, A.
Wave effects on sediment dynamics in a macro-tidal estuary—Darwin Harbour, Australia during the monsoon season Yang, G.
SHOWING 10 OF 19

Variables

The table below lists the variables contained within a single granule for this dataset. Variables often contain observed or derived geophysical measurements collected from a variety of sources, including remote sensing instruments on satellite and airborne platforms, field campaigns, in situ measurements, and model outputs. The terms variable, parameter, scientific data set, layer, and band have been used across NASA’s Earth science disciplines; however, variable is the designated nomenclature in NASA’s Common Metadata Repository (CMR). Variable metadata attributes such as Name, Description, Units, Data Type, Fill Value, Valid Range, and Scale Factor allow users to efficiently process and analyze the data. The full range of attributes may not be applicable to all variables. Additional information on variable attributes is typically available in the data, user guide, and/or other product documentation.

For questions on a specific variable, please use the Earthdata Forum.

Name Description Units Data Type Fill Value Valid Range Scale Factor
granule_pnt _1 Granule pointer N/A uint8 255 0 to 254 N/A
iobs_res_1 Observation number N/A uint8 255 0 to 254 N/A
num_observations Number of observations per 250m pixel N/A int8 -1 0 to 127 N/A
obscov_1 Observation coverage Percent int8 -1 0 to 100 0.01
orbit_pnt_1 Orbit pointer N/A int8 -1 0 to 15 N/A
QC_250m_1 Surface Reflectance 250m Quality Assurance Bit Field uint16 2995 0 to 4096 N/A
sur_refl_b01_1 Surface Reflectance Band 1 N/A int16 -28672 -100 to 16000 0.0001
sur_refl_b02_1 Surface Reflectance Band 2 N/A int16 -28672 -100 to 16000 0.0001
You're viewing 8 of 8