Lighting strikes are double the average in shipping lanes https://www.economist.com/news/science-and-technology/21729974-lighting-strikes-are-double-average-shipping-lanes-pollution-ships MODERN, broad-beamed merchant vessels are well able to withstand the rough and tumble of the waves, but sailors still prefer to avoid storms at sea if they can. Containers may come loose in heavy weather and there is always a chance of lightning knocking out communications. It is therefore ironic that some storms may be caused by ships themselves. That, at least, is the conclusion reached by Joel Thornton of the University of Washington, in Seattle, and his colleagues in a paper just published in Geophysical Research Letters. They demonstrate that lightning strikes the Indian Ocean and the South China Sea almost twice as often along shipping lanes as it does other areas of these waters. ... The most likely explanation is particulate pollution emitted by the ships using the shipping lanes. Marine diesel burned offshore is generally high in sulphur, and its combustion produces soluble oxides of that element which act as nuclei for the condensation of cloud-forming droplets. Typical marine clouds in unpolluted areas are composed of large droplets and do not rise to high altitude, but Dr Thornton and his team reckon that smaller droplets, of the sort that condense around oxides of sulphur, might more easily be carried upward by convection—forming, as they rose, into towering storm clouds that would act as nurseries of lightning bolts. ... ...for any who may doubt humanity’s ability to affect the weather, Dr Thornton’s work provides strong evidence that it can.