012 
(R2=0.94). 
> thickness 
condition. 
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AMSR-E 
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However, 
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Thus, the 
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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B8, 2012 
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia 
Figure 10 shows scatter plots of 19GHz versus 37GHz at 
vertical polarization brightness temperatures of AMSR-E used 
in Bootstrap Algorithm for the sample areas. This characteristic 
domain is used for calculating ice concentrations in Bootstrap 
Algorithm. It is clear that the thin ice area ( ?) can’t be 
identified with the ice floe(consolidated ice #) in this scatter 
plots. So, the authors have introduced the scatter plots of 
AMSR-E (19GHz V-19GHz H) versus 37GHzV as shown on 
Figure 11. Since thin ice areas are likely to be wet, the 
polarization difference of 19GHz brightness temperature in thin 
ice area increases than big ice floe (consolidated ice). As a 
result, the thin ice area(<*) could be discriminated from big ice 
floe(#) in the scatter plots on Figure 11. The authors have 
introduced following two equations for extracting thin ice area. 
  
  
TB(19GHzV — 19GHzH) +TB(37GHzV)>300K (1) 
TB(19GHzV)>245K (2) 
The meshed area represents the area extracted with equation (1). 
Equation (2) is used to reject the sea ice area which 
concentration is less than approx. 80%. The red area in Figure 
12(a) are the “thin ice areas” extracted with this method. The 
extracted areas were overlaid on the MODIS image for 
evaluation as shown on Figure 12(b) and (c). It is clear that 
most of the thin ice areas which are appearing in dark purple in 
the MODIS image are successfully extracted with the proposed 
method. Up to now, we have applyed this method to around ten 
AMSR-E scenes for the Sea of Okhotsk with success. 
  
  
  
  
  
  
  
  
> 
E : : Sagat. ol : 
@ Gan Sea of Okhotsk 
x 19 p eot # A-ice floe 
i e ee i s od + B-Thin ice 
  
À C-Mixed zone 
  
3$ D-Mixed zone 
  
  
+ E-Qpen water 
  
  
  
  
  
  
  
200 ne 220 230 240 250 260 
  
  
AMSR-E T837V 
  
Fig.10 Scatter plots of 19GHz vs 37GHz at V polarization 
(Sea of Okhotsk, 2009/02/07) 
  
  
  
  
80 
76 
t. 
3 90 
n 
3 5 
x Sea of Okhotsk 
E ao 
ui 
n 3$ A-ice floe 
P 
2% ssThinice 
20 à C-Mixed zone 
zm & D-Mixed zone 
x E-Open water 
0 
200 210 220 230 240 250 260 
AMSR-E Te37V 
  
Fig.11 Scatter plots of Tg(19GHzV-19GHzH) versus 
Tp(37GHzV) 
= 
  
(a) AMSR-E image (Red: extracted area) 
  
(b)MODIS image 
  
(c) Expansion of the extracted area overlaid on MODIS 
image 
Fig.12 Thin ice area extraction result