Tropical cyclone activity over Madagascar during the late nineteenth century

摘要

Tropical cyclones (TCs) represent the most significant natural hazard for the economy and population of Madagascar. Planning for the impacts of future cyclone strikes requires a detailed understanding of the frequency of destructive storms in the past. In this paper, we utilise historical documentary materials to construct an initial framework of TCs making landfall on Madagascar during the latter half of the 19th century. The study focuses on 1862-1900 as this is the period of most extensive documentary records. Accounts of storm damage contained within historical sources are used to reconstruct TC tracks over land, with details of wind damage converted into Fujita (F) Scale classes to classify TC intensity. A total of 20 TCs are identified, of which only 17 are included within the IBTrACS dataset for the southwest Indian Ocean. The TCs of 13-14 March 1872 and 28 January-1 February 1893 were the most destructive of the late 19th century, with F3+ levels of wind damage identified from historical accounts. We compare our results with data for TCs within the IBTrACS dataset that made landfall on Madagascar during the period 1970-2012. This comparison suggests that (1) fewer TCs made landfall during the 19th century compared with the post-satellite era, but that of these (2) a greater proportion appear to have crossed the northeast of the island. There is no significant correlation between numbers of landfalling TCs and either mean annual SOI or DMI. We conclude with a consideration of additional archival collections that may be used in future investigations to enhance our chronology.