A Reduction in Rainfall Associated with Smoke from Sugar-Cane Fires—An Inadvertent Weather Modification?

An examination of 60 years of rainfall during three months of the cane-harvesting season has shown a reduction of rainfall at inland stations coinciding with increasing cane production; no such reduction occurred at a “control” station upwind of smoke from the cane fires. The reduction is consistent with the hypothesis that through their activity as condensation nuclei the smoke particles result in great increases in concentration and consequent reduction in the size of cloud droplets, thereby hindering the coalescence process of rain formation. However, the possibility that other factors caused the particular climatic changes observed cannot be eliminated, and it is suggested that other areas of the world should be examined to see if similar effects can be found.