This website explains how we observe and measure aerosol particulate matter from space using the dark target retrieval technique and why it is important for the scientific community and the public to have this information.

We are writing for several audiences:

   1.  People who are fairly new to this topic and want to know more either for general knowledge and/or to begin the process of learning enough to be able to use the products.   If this is you then first read the content under the "Aerosols" tab.   This section will have brief explanations of the why and how we study aerosols with links to the much more detailed information contained in the Algorithm Theoretical Basis Document (ATBD) section of the website.

   2.  Users who simply want to know how and where to obtain the products, how to use them and how we evaluate their quality should go directly to the "Products" section.

   3.  Advanced users who want to know precise details about how the "Dark Target" algorithm works should use the "ATBD" section of the website.

Users should note that the dark target technique was originally developed for use on NASA's polar orbiting MODerate Resolution Imaging Spectroradiometer (MODIS) senor.  As such we begin each part of the Aerosol Overview pages with an explanation of how the retrieval methodology works with the MODIS sensor and data and then explain how dark target has been modified for use with the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument which is also a on a polar orbiting platform. 

Dark target is currently being adapted for use with geosynchronous instruments (GEO) such as the Advanced Baseline Imager (ABI) about NOAA's GOES 15 satellite platform and and Advanced Himawari Imager (AHI) aboard the Japanese Meteorological Agency's Himawari 8 satellite platform.   As we develop dark-target based products for these sensor we will add information on separate pages for Geo Instruments.