UPDATE: Here is a link to a video to Prof. Castilla’s talk (via @sthlmresilience)
03:34 a.m. February 27th 2010. Suddenly, a devastating earthquake and a series of tsunamis hits the central–south coast of Chile. An earthquake so powerful (8.8 on the moment magnitude scale), that not only is the fifth largest recorded on earth, but also moves the city of Buenos Aires in Argentina, 10 feet (!) to the west.
Juan Carlos Castilla from the Pontificia Universidad Católica de Chile, recently visited Stockholm, and gave an update about the tsunamis’ impact on coastal communities. The effects of the tsunami were devastating, and the death toll from the 2-3 tsunamis alone was between 170-200 in the coastal areas of regions VI, VII and VIII. The most noticeable biophysical impact in the region is the elevation of the whole coastal area, ranging from 1.5 to 3 meters. This obviously has had big impacts on the composition of species and vegetation on the coast. The impacts on coastal ecosystems and fisheries is however still unclear.
Based on extensive field studies two months after the disaster, Castilla and his research team noted that only 8-12 (about 6%) of the 200 deceased where from fisherman families. According to Castilla, this low figure can be explained by the existence of strong social networks, and local knowledge passed on from generation to generation. As an artisan fisherman in the study, summarized one shared local saying:
“if an earthquake is so strong you can not stand up: run to the hills”
Luckily, February 27th was a night of full moon. This allowed people to more easily run for protection in the hills. According to Castilla, the combination of full moon, local knowledge, and strong bonds between neighbors, made it possible for members of fishermen communities to rapidly act on the first warning signal: the earthquake. The fact that locals also were taught not to leave the hills after at least a couple of hours after an earthquake, also helped them avoid the following devastating tsunamis. Unfortunately, visitors and tourists in the tsunami affected coastal areas, were not.
Read more:
Marín, A et al. (2010) ”The 2010 tsunami in Chile: Devastation and survival of coastal small-scale fishing communities”, Marine Policy, 2010, 34:1381-1384.
See Henrik’s post just the days after the Chilean earthquake here.