We study temperature effects on the characteristic time for which charge carriers remain spatially confined while interacting with fluctuational openings (bubbles) of double stranded DNA. Using semiclassical molecular-dynamics simulations, we find that in the low-temperature regime this characteristic time decreases in a power-law fashion with temperature and coincides with the polaronic lifetime. However, above 50-70 K the confinement time exhibits an exponential increase with temperature. We demonstrate that this enhanced trapping is a result of intrinsic dynamical structural disorder resulting from thermal fluctuations. Specifically, nonlinearity-induced hot spots in the lattice subsystem form breathing potential barriers confining the charge for substantially longer times. (C) 2003 American Institute of Physics.