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factor for 
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SMR data. 
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ry-March, 
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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004 
  
Similar observations were made using OCM data from 2000 to 
2004 also from weekly images of February. The period 
February-March coincides with northeasterly winds. Hence, the 
observed bloom is believed to have occurred due to annual 
cycle of convection favourable winds. This has been verified in 
the study reported here. Trade winds from the northeast are 
predictable and therefore, the observed bloom is also 
predictable in nature. 
Weekly averaged wind speed was estimated from MSMR data 
of 1* week of March 2001 for the oceanic waters of NAS and 
weekly averaged Mixed Layer Primary Production images for 
the same period. This can be seen in Figure 2A and 2B. 
  
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251 
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Figure 2A. Weekly averaged (March 1? week, 2001) wind 
speed from MSMR 
  
  
  
Figure 2B. Weekly averaged (March 1? week, 2001) Primary 
production from OCM with window showing location of wind 
Speed estimates in Figure 2A. 
It can be seen from Figure 2B that Primary Production varies 
from low productivity zone (blue) to high productivity zone 
(yellow, red). High productivity can be seen dominating in off 
shore waters (> 2000 m) that is unusual. Also, it can be noticed 
that where wind speed is high (Figure 2A), Primary Production 
is also high correspondingly (Figure 2B). On the other hand, 
relatively weaker winds correspond to low productive zone. 
Pattern of relatively higher wind speed at the centre of image 
(yellow and red patch at locations 1 and 2, Figure 2A) is 
correspondingly accompanied by patches of high productivity 
(Figure 2B). However, right corner of productivity image (blue 
at location 3, Figure 2B) is less productive supported by a 
pattern of relatively lower wind speed (Figure 2A) for the same 
area. 
This means that, in open NAS, wind generated mixing could be 
important mechanism by which nutrients are entrained into 
surface layers. 
Figure 3 shows time series chlorophyll and SST images 
generated from OCM and AVHRR data respectively. 
    
  
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Figure 3. Time series chlorophyll and OCM images generated 
from OCM and AVHRR data 
A clear demarcation (dotted lines) between high and low 
productivity can be made in upper and lower portion of series 
of chlorophyll images. Corresponding to higher chlorophyll 
concentration on upper side, SST images show relatively cooler 
waters over all in this portion, which is influenced by bloom. 
Converse to this, lower chlorophyll and signature of warm 
water masses can be seen in the lower portion pertaining to 
non-bloom waters. These observations from satellite data 
comply with the hypothesis that describes coupling between 
increase in Primary Productivity and cooling of surface waters 
due to wind force and resulting convection. The observed 
pattern of inverse correlation between chlorophyll and SST is 
due to this forcing action. Otherwise, the waters being studied 
is off shore waters at depths greater than 2000 m in NAS where 
so-called biological-physical coupling often breaks down. 
Temporal profile of variations in chlorophyll and wind speed 
using OCM and Quick scat data is shown in Figure 4.