  Recently, different transport coefficients have been measured in High-Tc
superconductors to pinpoint the nature of the pseudogap phase. In particular,
the thermoelectric coefficients received a considerable attention both
theoretically and experimentally. We numerically simulate the Nernst effect in
extreme type-II superconductors using the time-dependent Ginzburg-Landau
equations. We report the sign reversal of the thermoelectric coefficient,
alpha_xy, at temperatures close to the mean-field transition temperature,
Tc^{MF}(H), which qualitatively agrees with recent experiments on high-Tc
materials. We also discuss the noise power spectrum of alpha_xy, which shows
1/f^beta behavior. Based on this observation, we propose an experiment to
distinguish among different regimes of vortex dynamics by measuring the noise
correlations of the Nernst signal.
