  In this paper we obtain quantitative bounds on the maximal order of vanishing
for solutions to $(\partial_t - \Delta)^s u =Vu$ for $s\in [1/2, 1)$ via new
Carleman estimates. Our main result Theorem 1.1 and Theorem 1.3 can be thought
of as a parabolic generalization of the corresponding quantitative uniqueness
result in the time independent case due to R\"uland and it can also be regarded
as a nonlocal generalization of a similar result due to Zhu for solutions to
local parabolic equations.
