Random Walk Simulation on Annual Precipitation in 62 African Major Cities for the 20th Century

Abstract

This is the continuation of our studies to use the random walk to simulate the annual precipitations in the 20the century in the major cities around the world. In this study, the annual precipitations in 62 African major cities were simulated using the random walk. The results show that the random walk is relatively easy to simulate the annual precipitations in the classical random walk form, but is much difficult to simulate the real annual precipitations. In conjunction with our previous studies, the results suggest (i) the random mechanism could be the main cause for the unpredictable and irregular annual precipitations at least in some parts of the world; (ii) the random walk could be possible to predict the general trend of annual precipitation for a short-term using its best seed of simulation, and (iii) the random walk has far less model parameters. However, (1) the random walk is still very hard to simulate the real annual precipitations; (2) the Monte Carlo algorithm makes the search for seeds difficult; and (3) the random walk simulation is time-consuming and computationally intensive.