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You can also download the MODIS monthly Chla from L3/4 browser, or try the methods described here: https://oceancolor.gsfc.nasa.gov/data/download_methods/

Let us know if you find these helpful.
Guoqing

Hello,

You can download multiple files using the methods described on this webpage: Data Search and Download Methods.

Please try these methods and let us know if you find them helpful.

Thank you.
Guoqing

Hello,

Do you have access to other ocean color webpages? If not, please send a note to:

connection_problems@oceancolor.sci.gsfc.nasa.gov

And indicate the IP address(es).

Thank you.
Guoqing

They are global algorithms, based on similar assumptions, and use the blue-green band ratios. Chlorophyll algorithm is a little complicated with the blend of a band difference and band ratio algorithms.

Hello, if you downloaded the data from oceancolor website, to better help with this question, can you share one of the file's name you have got? This will help us identify which level (L2 or L3) and what format of data you are using.

You can find the information on the following ATBD and the corresponding reference:
https://www.earthdata.nasa.gov/apt/documents/chlor-a/v1.0#doc-header

@tlin2_cuny.edu @haag
Please email "connection_problems@oceancolor.gsfc.nasa.gov" with the public ip address you are connection from, the time you tried to connect and a short description of the network issue you are experiencing. The NASA OBPG network team will assist you.

Please email "connection_problems@oceancolor.gsfc.nasa.gov" with the public ip address you are connection from, the time you tried to connect and a short description of the network issue you are experiencing. The NASA OBPG network team will assist you.

Hello, The POC algorithm is mainly for open ocean or Case 1 waters, and it relies on the fact that variation in Rrs(λ) at blue wavelengths are primarily driven by phytoplankton pigments and covarying matters. For coastal or optically complex case 2 waters, the empirical relationship used in the algo...

Hi, First of all, here is the theoretic basis for the standard Chlorophyll-a algorithm we use: https://oceancolor.gsfc.nasa.gov/resources/atbd/chlor_a/. Second, yes, for coastal regions, the standard Chlorophyll-a values tend to be higher due to the optical complexity of the water. That said, the op...