Abstract:
MODIS was launched aboard the Terra satellite on December 18, 1999 (10:30 am equator crossing time) as part of NASA's Earth Observing System (EOS) mission. MODIS with its 2330 km viewing swath width provides almost daily global coverage. It acquires data in 36 high spectral resolution bands between 0.415 to 14.235 micron ... with spatial resolutions of 250m(2 bands), 500m(5 bands), and 1000m (29 bands). MODIS sensor counts, calibrated radiances, geolocation products and all derived geophysical atmospheric and ocean products are archived at NASA Goddard DAAC and has been made available to public since April 2000.
This is a level-3 MODIS gridded atmosphere daily global joint product 'MOD08_D3'. It contains daily 1 x 1 degree grid average values of atmospheric parameters related to atmospheric aerosol particle properties, total ozone burden, atmospheric water vapor, cloud optical and physical properties, and atmospheric stability indices. This product also provides standard deviations, quality assurance weighted means and other statistically derived quantities for each parameter. The shortname for this level-3 MODIS atmosphere daily global product is MOD08_D3 and the principal investigator for this product are MODIS scientists :
Dr. Yoram Kaufman for aerosol retrieval over land; Dr. Didier Tanre ( didier.tanre@univ-lille1.fr) for aerosol retrieval over ocean; Dr. Bo-Cai Gao (gao@rsd.nrl.navy.mil) for cirrus cloud detection; Dr. Paul Menzel (paulm@ssec.wisc.edu) for cloud top properties ; and Dr. Michael King(king@climate.gsfc.nasa.gov) for cloud optical properties.
The level-3 atmosphere daily global product (MOD08_D3) consists of approximately 500 parameters that includes all statistically derived quantities. Essentially all level-3 MODIS atmosphere daily global parameters are derived from the four level-2 MODIS atmosphere products MOD04_L2, MOD05_L2, MOD06_L2, and MOD07_L2. Statistics are computed over a 1 degree equal-angle lat-lon grid that spans a 24-hour (0000 to 2400 Greenwich Mean Time) interval. Since the grid cells are 1 degree by 1 degree, the output grid is always 360 pixels in width and 180 pixels in length.
MOD08_D3 product files are stored in Hierarchical Data Format (HDF-EOS). Each gridded global parameter is stored as Scientific Data Sets (SDS) within the file. For browsing and extracting data from these files, some software are made available at the site: http://ladsweb.nascom.nasa.gov/tools/ .
MOD08_D3 PARAMETERS
Aerosol over Land and Ocean: Optical Depth (0.55 micron)
Aerosol over Land: Optical Depth at 0.47 and 0.66 (based on Continental Aerosol Model) Corrected Optical Depths at 0.47, 0.55, 0.66 mm (based on Dynamic Aerosol Model) Corrected Optical Depths at 0.47, 0.55, 0.66 mm for Smoke, Sulfate, Dust Aerosols Mass Concentration (based on 0.66 mm) Angstrom Exponents for Smoke, Sulfate, Dust
Aerosol over Ocean: Effective Optical Depth at 7 bands (0.47, 0.55, 0.66, 0.87, 1.24, 1.64, 2.13 mm) Effective Radius, Mass Concentration, Cloud Condensation Nuclei (based on 0.55 mm) Ratio: Optical Depth of Small Particles relative to Effective Optical Depth (0.55 mm) Asymmetry Factor & Back Scattering Ratio at 7 bands Angstrom Exponents 1 (based on 0.55 and 0.865 mm) & 2 (based on 0.865 and 2.13 mm)
Ozone: Total Column Ozone
Water Vapor: Total Column Precipitable Water Vapor NIR based (clear, cloudy), IR based (lower, upper levels, total)
Cloud: Cloud Top Parameters Cloud Top Pressure, Temperature, and Effective Emissivity(day, night, all) Cloud Particle Phase Infrared & Visible based retrievals (day, night, all) Cloud Optical Thickness and Effective Radius (water, ice, water + ice, undetermined, all phases) Cloud Water Path (liquid, ice, liquid + ice, undetermined, all phases) Cloud Fraction Visible and SWIR based (cirrus, contrail, water, ice, water + ice, undetermined, all phases) & IR based (day, night, all)
Atmospheric State & Stability Indices: Total -Totals, Lifted Index, K Index
Radiation Parameters: Cirrus Cloud & Contrail Reflectance Mean Surface Reflectance for Land (5 bands) and Ocean (7 bands) Normalized Reflected Flux for Land (0.47 and 0.66 mm) and Ocean (7 bands) Normalized Transmitted Flux for Land (0.47 and 0.66 mm) and Ocean (7 bands) Atmosphreic Scattering Angle for Land and Ocean
Quality Assurance (QA) & Statistical Parameters: Uncertainty in Derived Parameters, Minimum, Maximum, Number of Pixels, Histograms, Correlation Parameters, QA Weighted, and other Statistically Derived Parameters
More information about the atmospheric parameters and the statistically derived parameters of MOD08_D3 product listed in the table above are available from the MOD08_D3 web site.
The MODIS Daily Product will be used in the simultaneously study of clouds, water vapor, aerosol , trace gases, land surface and oceanic properties, as well as the interaction between them and their effect on the Earth's energy budget and climate. This product will also be used to investigate seasonal and inter-annual changes in cirrus (semi-transparent) global cloud cover and cloud phase with multispectral observations at high spatial resolution.
