Cosmic ray long-term variation: Even-odd cycle effect, role of drifts, and the onset of cycle 23

Estimations of cosmic ray time-lags in long-term variations for solar cycles 19-22 show that there are large differences between odd and even solar cycles. We assume that this odd-even effect in the hysteresis phenomenon is caused mainly by cosmic ray drift effects. The odd-even effect in time-lags we use for rough estimates of the relative role of drift effects in establishing long-term modulation. We also consider cosmic ray long-term modulation in the onset of Cycle 23 and discuss a method to predict cosmic radiation for 12 or more months on the basis of solar activity data in the frame of a developed convection-diffusion-drift model. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.