The Aqua and Orbview satellites carry a MODIS and SeaWIFS sensors (respectively) that observes sunlight reflected from within the ocean surface layer at multiple wavelengths. These multi-spectral measurements are used to infer the concentration of chlorophyll-a (Chl-a), most typically due to phytoplankton, present in the water.
There are multiple retrieval algorithms for estimating Chl-a and aggregating the data over time. This data set is a reprocessed copy of 9km monthly and 8-day versions produced globally by NASA, adjusted for the Southern Ocean south of latitude 30S. The full methodology is described in Johnson, R., Strutton, P.G., Wright, S.W., McMinn, A., Meiners, K.M., 2013. Three improved satellite chlorophyll algorithms for the Southern Ocean. Journal of Geophysical Research: Oceans. doi: 10.1002/jgrc.20270. It is expected that the data set will be periodically updated with contemporary data as it becomes available.
There are four sub-streams within this data set. A monthly and an 8-day series for MODIS/Aqua and similarly for SeaWIFS. Note that SeaWIFS ceased operation in late 2010 so there will be no further SeaWIFS data.
The data represented by this record is monthly data for MODIS/Aqua.
Statement: Original Rrs data were from MODIS-Aqua reprocessing R2013.0 NASA GSFC http://oceandata.sci.gsfc.nasa.gov/MODISA/Mapped/8Day/9km/Rrs/
****NETCDF FILENAMING CONVENTION FOR AQUA FILES****
The filenaming scheme puts a lot of useful metadata into the filename with the aim of making it easy to parse by machine and eye.
Folder D-20120802.G-0720.P-aqua.C-20120802082919.T-d263047n000000.S-m.E-definitive.Z-ok.R-20120802185051/ --
Folder D-20120802.G-0715.P-aqua.C-20120802111359.T-d549724n000000.S-mn.E-definitive.Z-ok.R-20120802185343/ --
Folder D-20120802.G-0710.P-aqua.C-20120802111224.T-d549724n000000.S-mn.E-definitive.Z-ok.R-20120802185344/ --
Folder D-20120802.G-0545.P-aqua.C-20120802101905.T-d549724n000000.S-na.E-definitive.Z-ok.R-20120802185437/ --
Folder D-20120802.G-0540.P-aqua.C-20120802101900.T-d549724n000000.S-cmna.E-definitive.Z-ok.R-20120802185314/ --
Folder D-20120802.G-0535.P-aqua.C-20120802101855.T-d549724n000000.S-cmna.E-definitive.Z-ok.R-20120802185436/ --
Folder D-20120802.G-0405.P-aqua.C-20120802084036.T-d549724n000000.S-qna.E-definitive.Z-ok.R-20120802185313/ --
Split the names on ‘.’, and then you have NAME-VALUE pairs where
D = GMT Date
G = GMT Acquisition
P = Platform
C = Creation date/time (yyyymmddhhmmss)
T = number of modis packet types (d=day packets, n=night packets)
S = contributing reception stations (a=Alice Springs, c=Crib Pt, m=Murdoch, q=AIMS, n=NASA DAAC)
E = Ephemeris (predicted or definitive)
Z = L1B processing status (should always be ok for these data)
R = date/time of processing of L2 Chl granule (but I forget what R stands for)
Commonwealth Scientific and Industrial Research Organisation (CSIRO)
Institute for Marine and Antarctic Studies (IMAS), University of Tasmania (UTAS)
Australian Research Council Centre of Excellence for Climate System Science
Antarctic Climate and Ecosystems Cooperative Research Centre (ACE CRC)
Australian Antarctic Division (AAD)
Integrated Marine Observing System (IMOS).
National Aeronautics and Space Administration (NASA)