| Summary: | Progress Code: completed Statement: CHL (mg per cubic metre) and AOD were obtained from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) archive for the period Sept 1997 - Feb 2004. Level 3 (9x9 square kilometre) 8-day binned data representing 46 products per year were processed into standard mapped image (SMI) format. The AOD is proportional to aerosol particle concentration from the ocean surface to the top of the atmosphere and can be retrieved with an accuracy of 10%. This resulted in 323 images layered into composite files for each of CHL and AOD. Sea ice data were obtained from the 'Nimbus-7 SMMR, DMSP SSM/I Passive Microwave Data, Daily and Monthly Polar Gridded Sea Ice Concentration' data administered by the National Snow and Ice Data Centre (NSIDC). The wind speed climatology was obtained from the NCAR data repository (Scientific Computing Division Data Support Section, Boulder, CO). The time series were analysed in four global latitude bands: 50-55 S, 55-60 S, 60-65 S and 65-70 S. Five-period moving averages were used to analyse temporal trends between mean CHL and AOD using data from each octad. Cross-correlation was then used to determine the relationship between parameters within each global band with a plus or minus 7 period lag. A lag of L periods referred to the correlation of CHL(t) with AOD(t=t+L). In the (60-70 S) band, data were only available from Sept-April due to the Antarctic winter. To retain valid sample sizes, bi-yearly data-sets were lagged and then appended to create a single multi-year data set (1997-2004) within each latitude band. The relationship between CHL and AOD was also explored in the longitudinal sectors: a) the Eastern Antarctic (110-140 E, 60-70 S), b) the Ross Sea (160-135 W, 60-80 S) and c) the Weddell Sea (65-0 W, 55-80 S). To explore the contribution of the SIZ to algal productivity and aerosol loads we compared the temporal cycles in CHL, AOD and sea ice cover. Mean monthly ice cover was calculated for the period Jan 1997 - Dec 2003 for 2 degree global latitude ...
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