After Archer and Trip are picked up on the surface, Archer and T’Pol are saying farewell to Zobral they have this conversation:
[Launch bay]
ZOBRAL: My launch window opens in nine minutes. I should be going. I hope Commander Tucker is going to be all right.
ARCHER: I doubt I'll ever convince him to set foot on another desert, but he'll be fine. Zobral, even if I were the warrior you thought I was, that's not why we're out here.
What’s interesting to me is that T’Pol maintains her perfect Vulcan composure until Archer says “I doubt I'll ever convince him to set foot on another desert,” at which point she reacts by blinking once then turning her head and eyes to look at Archer for a second or two before regaining her composure.
So, what do people think is so distressing to T’Pol about that statement that she loses her composure?
I suspect it has something to do with the fact that Vulcan is a desert planet, that causes her to react that way.