Correction to Oluf's post #1456 - Boeing look at engine icing on the basis of TAT, not OAT, so although 038 may well have been in 'engine icing conditions' during the descent, that would have been due to TAT.
Also to say that some of us (pilots) are aware of engine icing risks above 'normal' altitudes. Boeing say one can ignore engine icing with a SAT of -40C or below unless throttled back. I have been somewhat more cautious than that for some time and I suspect that 'rule of thumb' may change.