RAPPORT DU GROUPE DE TRAVAIL VII-8 
W. G. VII-8 Report 
"GLACE-ET- NEIGE" 
"Ice and snow" 
PAR 
C. MATZLER 
R.K. HAWKINS 
Several papers were given which discussed remote sensing techniques for ice and 
snow covering mainly microwaves but also IR and more traditional methods. This 
report is divided into sea ice and snow as topics and further by the applica- 
tion of active and passive techniques. 
SNOW 
With two frequencies, microwave radiometers can determine areal extent, estimate 
water equivalent and detect the onset of melt metamorphism. More accurate water 
equivalent measurements and the classification of snow types will be possible 
when two polarizations and three frequencies are employed. Several unusual 
signatures were however observed which were related to snow metamorphosis. 
These results were obtained with ground-based measurements and further shown 
to give good agreement with independent snow observations when NIMBUS 7, 
SMMR data were analyzed. 
The areal extent of wet snow in mountainous terrain can be determined by use of 
X-Band radar imagery. 
SEA ICE 
Skilled interpreters using image brightness, context, floe shape and texture as 
clues from high resolution X-Band SAR, can separate a range of ice forms 
during cold winter conditions. Radar contrasts alone may be used to separate 
old ice from young ice, but with the addition of a p-wave radiometer, much more 
distinct clusters exist which have been successfully tested using MAP classifiers. 
There are however a large variety of ice forms and conditions, which complicate 
this simple situation. Examples are the metamorphosis which occurs during the 
melt season and the wide range of conformations and compactions encóuntered 
in the Marginal Ice Zone (MIZ). 
Passive microwave radiometers have shown good classification potential in young 
and new ice forms studied in the MIZ. Ice concentration analysis using two or 
more frequencies have demonstrated performances of + 3% (ice-water) and 
   
  
    
    
    
    
  
  
  
  
  
  
  
  
  
  
  
    
    
    
   
  
    
    
   
  
  
    
    
    
   
   
    
+ 10% f 
for spa 
The sam 
shelves 
SAR usi 
New cor 
measure 
Water p 
MISCELL 
- Coher 
in an o 
though 
Multi-1 
- Disti 
which e 
machine 
- There 
passive 
- Activ 
> L-Ban 
- ISPRS 
with th 
CONCLUS 
The cry 
Several 
dynamic 
shown t 
questio