Dear Colleagues,
I am investigating the development (increase) in coastal marine water turbidity around La Réunion Island, France over the past two decades. My research area extends less than 70 km along the western coast. Which ocean color product(s) / sensor(s) can you recommend? My requirements: high resolution, short revisit time, regular temporal coverage since around 2000.
I am very thankful for your help and any advice! Looking forward to hear from you, kindest regards!
Study of coastal water turbidity in Réunion Island
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OB.DAAC - SeanBailey
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Study of coastal water turbidity in Réunion Island
A lot depends on the definition of high resolution. If you can accept 250m-ish, and don't mind processing the data locally...MODIS Rrs_645nm might serve as a decent proxy for turbidity...300m-ish, MERIS with 709nm available...if you can live with 1km-ish, again MODIS and MERIS, but also just about every other mission we support. Need better than that? You don't have much to choose from...Landsat, but pre L8 is not very useful for ocean work
Sean
Sean
Study of coastal water turbidity in Réunion Island
Dear Sean, thanks for your answer! I think for the start the MODIS Rrs_645nm should be ok. Is it right that a file ending with .L2_LAC_OC.nc contains this product (under Rasters - Rrs - Rrs_645 (645 nm))? How can I show/display the quasi true color image of this scene in SeaDAS? Which exact file in the Level 1&2 Browser contains the quasi true color information? Thank you!
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OB.DAAC - SeanBailey
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Study of coastal water turbidity in Réunion Island
The standard MODIS L2 files we produce are (nominally) 1km resolution. While they do have the 645nm Rrs data, to get the 250m resolution you would have to process the L1 files to L2 locally and set resolution=250
We do not provide a quai-true color image in any of our products. You can generate it from the L1 data with the tools provided in SeaDAS (l1brsgen or l1mapgen). You could also create one with the "View->RGB Image" tool in the SeaDAS GUI.
...or cheat and look here: https://worldview.earthdata.nasa.gov/
Sean
We do not provide a quai-true color image in any of our products. You can generate it from the L1 data with the tools provided in SeaDAS (l1brsgen or l1mapgen). You could also create one with the "View->RGB Image" tool in the SeaDAS GUI.
...or cheat and look here: https://worldview.earthdata.nasa.gov/
Sean
Study of coastal water turbidity in Réunion Island
Dear Sean, thanks for all the helpful information! Greetings, JC