Overview

TSM is a measure of sediment concentration. We use the term "index" to refer to a quantity that varies linearly with TSM but is not actual calibrated TSM in mg/l. MODIS data are obtained from the NOAA facilities at NASA/GSFC. Data are processed daily by NOAA CoastWatch and made available on this website and the CoastWatch FTP server.

TSM Index pixels are colored purple/blue for clear water and green/yellow/orange/red for high suspended matter concentration.
The search interface is updated daily, and can be used to find true color images (MODIS Bands 1/4/3 mapped to 1 km and 250 m resolution) and corresponding TSM Index images (derived from MODIS Band 1 and mapped to 1 km and 250 m resolution).

What are the gray areas in the TSM image?

For the purposes of this demonstration, clouds in the TSM data are masked to gray using an empirical "whiteness" test, such that some cloud edges appear to be surrounded by higher suspended matter concentration when in fact the pixels are contaminated by cloud. It is best to use the true color image for judging cloud cover.

How accurate is this data?

This demonstration is for visual purposes only! Data from different satellites and different days should not be intercompared, as some of the corrections for viewing angle, illumination, and atmospheric effects have not been taken into account.

Questions?

For additional information, please send general questions to Shawna Karlson, imagery questions to Michael Soracco, and TSM questions to Peter Hollemans.