In this episode of Science Sunday, I’m leaving behind religious discussions and opening up Geology, January 2015; v. 43; no. 1; p. 91–94 to a rather interesting article titled, “Depositional evidence for the Kamikaze typhoons and links to changes in typhoon climatology.” I’ll begin with a little background.
In the 13th century Kublai Khan twice tried to invade and ultimately conquer the Japanese islands. Both campaigns were failures. Legend has it Khan was defeated both times — not by the Japanese army, which was vastly outnumbered and ill-equipped to protect themselves — but by massive typhoons that utterly destroyed Khan’s fleets, which, without evidence, is extremely unlikely because typhoons are extraordinarily rare in that region. Legend also has it the Japanese called these super storms “kamikaze,” or divine wind, suggesting, perhaps, that the Japanese thought there was a supernatural explanation for the storms, and that they believed a divine being was protecting them from Khan’s fleets. There is no question of whether or not Khan was defeated; remains of his fleets have been discovered in recent centuries. The question is whether or not typhoons were to blame for his defeat, or to what extent they were to blame. Now four researchers from the University of Massachusetts and Worcester State University suggest there might be some merit to the “kamikaze” legend.
These researchers were investigating extreme coastal flooding event deposits in the coastal lakes where Khan’s fleet was destroyed. In their analysis of these deposits, the sediments suggest typhoon activity in that region was “greater during the time of the invasions.” Moreover, a deeper analysis suggested “that it is highly probable that two intense overwash events occurred in the region during the late 13th century,” meaning during the time of Khan’s invasions, two major climate events took place. The authors are very honest about their limitations and do not claim to know this for a fact, but they have confidence in their results.
Despite these very interesting results, the authors brush it off in the discussion chapter, focusing instead on how this evidence actually supports a different established climatological theory. Suggesting a subsequent (and necessary if their results are correct) decrease in typhoon activity, they close with:
The decrease in typhoon frequency at Lake Daija and Kamiko-shiki at 1600 CE also occurs during a transition to more documented typhoon strikes in the Guangdong Providence of southern China (Fig. 4C; Liu et al., 2001); this is consistent with a southern shift in preferred typhoon tracks away from Japan and toward southern China following a transition toward more La Niña–like conditions, with fewer El Niño occurrences. It is all but certain that a majority of the rise in typhoon counts in the Guangdong record is artificial, due to an increase in the number of reliable storm accounts. However, the pattern toward better typhoon documentation may in part be due to heightened interest resulting from increased typhoon impacts in the region.
I chose to focus on an area outside of my field of knowledge, experience, or expertise because I wanted to give my readers access to a wider range of research. Personally, outside of undergraduate classes on geography and climate, this is the first time I’ve branched out into climatology. What is most interesting to me is these findings help my field — international political science — build upon or strengthen its theories or to build new theories. The fact that weather can possibly play such a major role in the outcome of two wars — especially when the victor was at such an extreme disadvantage — could help explain martial failures by US forces. I mean, this seems rather obvious at first glance, but you’d be surprised how little the weather is mentioned in political science, outside of environmental politics.
In other words, it’s my hope that your quest for knowledge is never limited to the field in which you get your degree or work. Even if you don’t have or never get a degree, being widely read is important because these fields are all connected, each one borrowing from the next. Political science borrows from math, engineering, and biology. Economics borrows from physics and political science. Understanding that will help you build stronger theories and analytical frameworks. Sometimes finding evidence of an 800 year-old storm is not just historical evidence; sometimes it’s evidence supporting a wide range of theories.