Greetings, all, from a ridiculously snowy Maryland. Hope that the New Year has been treating everyone well. On this Eve of the MODIS-Aqua reprocessing (assuming that tonight's snow doesn't accumulate or freeze), we'd like to reinitiate conversations regarding IOP algorithm implementation at NASA. With the radiometric corrections that accompanied preparation for the SeaWiFS
and Aqua reprocessings behind us, the goal of the OBPG is to refocus on bio-optical algorithms for the next few months. Here, I'll provide a very brief summary on what's been going on here and what we hope to accomplish in the near future, with the hope of sufficiently piquing your interest to provide comments, suggestions, and analyses in the coming months.
We left OOXIX tasked with developing a framework for configuring and testing SAAs, starting with a general spectral optimization model form. To that end, GIOP (Generic IOP) was developed and recently released via SeaDAS. Briefly, GIOP is an infrastructure for building a spectral optimization model on the fly -- the user chooses the inversion/optimization method (e.g., Levenberg-Marquardt, matrix inversion, etc.) and the eigenvectors for aphi (user-defined, Bricaud, Ciotti, etc.), adg (QAA, user-defined S), and bbp (QAA, user-defined eta, Loisel and Stramski eta, etc.) For example, GSM can be run using GIOP by defining the eigenvectors, etc. reported in Maritorena et al. 2002. GIOP will be expanded somewhat soon to include multiple eigenvectors for each parameter (e.g., ad and ag rather than adg). We're currently in the process of analyzing sensitivities of various parameter combinations.
The preliminary configuration for GIOP we decided upon at the conclusion of the workshop (PQN) will be used to generate a long time series of SeaWiFS and Aqua products that will be posted online for your perusal. While results aren't yet available, they will ultimately also be posted on our Level-2 match-up site (http://seabass.gsfc.nasa.gov/seabasscgi/validation_search.cgi
and Level-2 regional time-series site (http://oceancolor.gsfc.nasa.gov/cgi/regions.cgi
). Note that other data products (including IOPs) will be available via these metchanisms as well. Level-3 analyses for PQN will also be generated and distributed. On our to-do list is devising new ways and implementing existing ways to test Level-2 and -3 coverages, uncertainties (Wang et al. 2005, Lee et al. 2010, Moore et al. 2009, GlobColour, etc.), sensitivities, etc. We've also implemented the fuzzy logic methods of Mark D. and Tim M. to identify optical water types, with the goal of merging its capabilities with that of GIOP.
Probably enough news for now. Again, sorry for our absence during reprocessing, we hope this finds everyone well and look forward to hearing about what you've been up to over the year. I imagine you've accomplished or formulated ideas about many of the topics listed above (and hopefully, are willing to share). We'll write again a week or so after GSFC reopens for business.
J and the gang at the OBPG