The effect of atmospheric waves on aerosol nucleation and size distribution

Atmospheric waves can enhance the aerosol particle nucleation rate up to 5 orders of magnitude because of the strongly nonlinear effect of temporal fl uctuations in temperature and vapor pressures on the nucleation rate. The w ave amplitude is the most important wave characteristic controlling the mea n nucleation rate and net particle number concentration. A simple parameter ization of the enhancement in nucleation rate can be given at certain mean conditions. The enhancement is from 1 to 5 orders of magnitude if the tempe rature amplitude is 5 K. Since nucleation causes a wave periodicity in the aerosol number only for particles below 3 nm diameter, which is typically t he lower cut for particle counters, it will be difficult to directly observ e the effect of wave or eddy variability on the number of near-nanometer si ze particles. In larger particles the waves will cause an increase in the m ean number concentration. It is also difficult to observe a difference betw een the influence of nucleation on the number concentration and variations simply caused by vertical gradients in number concentration or fluxes of th ese particles.