Terra MODIS Near Real-Time Aerosol Optical Depth Grid

MODIS/Terra provides near-daily global aerosol observations from 36 spectral bands with spatial resolutions from 250m to 1000m. The Naval Research Laboratory and University of North Dakota produce this value-added Level-3 gridded product, MODAODHD, with new granules generated every six hours. This dataset applies empirical corrections and spatial averaging to the underlying Level-2 aerosol data to reduce biases and estimate uncertainty.

Use Cases

• Assimilating gridded AOD values and their quantitative uncertainty estimates into atmospheric transport models.
• Validating aerosol model outputs against spatially averaged AOD data filtered for cloud contamination and outliers.
• Analyzing global aerosol distribution and transport using six-hourly granules timestamped at 00:00, 06:00, 12:00, and 18:00 UTC.
• Studying aerosol-climate interactions using the enhanced product which reduces systematic biases over land and ocean.

Strengths

• Global coverage with a 2330 km viewing swath providing near-daily observations.
• Data incorporates stringent filtering to reduce outliers and eliminate cloud contamination.
• Product includes quantitative uncertainty estimation for each aerosol optical depth data point.
• Granules are produced every six hours in near real-time via the LANCE system.

Limitations

• Specific row count, column details, and sample size for the gridded product are not provided.
• Derived from MODIS Level-2 inputs, so dependent on the quality and availability of those upstream products.
• The description does not specify the exact spatial resolution or grid size of the final Level-3 product.

Provenance

Source

NASA's Earth Observing System (EOS) MODIS instrument aboard the Terra satellite, processed by LANCE-MODIS.

Collection Method

Developed by the Naval Research Laboratory and University of North Dakota through stringent filtering, empirical bias correction, and spatial averaging of MODIS Level-2 aerosol products.

Time Range

Data has been publicly available since April 2000; near real-time production is ongoing.

Freshness

Near real-time, with granules produced every six hours.

Geography

Global coverage.